text: # -*- coding: utf-8 -*-
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  # http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  #
  
  from past.builtins import basestring, unicode
  
  import os
  import pkg_resources
  import socket
  from functools import wraps
  from datetime import datetime, timedelta
  import dateutil.parser
  import copy
  import json
  
  import inspect
  from textwrap import dedent
  import traceback
  
  import sqlalchemy as sqla
  from sqlalchemy import or_, desc, and_, union_all
  
  from flask import (
      redirect, url_for, request, Markup, Response, current_app, render_template, make_response)
  from flask_admin import BaseView, expose, AdminIndexView
  from flask_admin.contrib.sqla import ModelView
  from flask_admin.actions import action
  from flask_admin.babel import lazy_gettext
  from flask_admin.tools import iterdecode
  from flask_login import flash
  from flask._compat import PY2
  
  import jinja2
  import markdown
  import nvd3
  import ast
  
  from wtforms import (
      Form, SelectField, TextAreaField, PasswordField, StringField, validators)
  
  from pygments import highlight, lexers
  from pygments.formatters import HtmlFormatter
  
  import airflow
  from airflow import configuration as conf
  from airflow import models
  from airflow import settings
  from airflow.exceptions import AirflowException
  from airflow.settings import Session
  from airflow.models import XCom, DagRun
  from airflow.ti_deps.dep_context import DepContext, QUEUE_DEPS, SCHEDULER_DEPS
  
  from airflow.models import BaseOperator
  from airflow.operators.subdag_operator import SubDagOperator
  
  from airflow.utils.logging import LoggingMixin
  from airflow.utils.json import json_ser
  from airflow.utils.state import State
  from airflow.utils.db import provide_session
  from airflow.utils.helpers import alchemy_to_dict
  from airflow.utils import logging as log_utils
  from airflow.utils.dates import infer_time_unit, scale_time_units
  from airflow.www import utils as wwwutils
  from airflow.www.forms import DateTimeForm, DateTimeWithNumRunsForm
  from airflow.configuration import AirflowConfigException
  
  QUERY_LIMIT = 100000
  CHART_LIMIT = 200000
  
  dagbag = models.DagBag(settings.DAGS_FOLDER)
  
  login_required = airflow.login.login_required
  current_user = airflow.login.current_user
  logout_user = airflow.login.logout_user
  
  FILTER_BY_OWNER = False
  
  DEFAULT_SENSITIVE_VARIABLE_FIELDS = (
      'password',
      'secret',
      'passwd',
      'authorization',
      'api_key',
      'apikey',
      'access_token',
  )
  
  if conf.getboolean('webserver', 'FILTER_BY_OWNER'):
      # filter_by_owner if authentication is enabled and filter_by_owner is true
      FILTER_BY_OWNER = not current_app.config['LOGIN_DISABLED']
  
  
  def dag_link(v, c, m, p):
      url = url_for(
          'airflow.graph',
          dag_id=m.dag_id)
      return Markup(
          '<a href="{url}">{m.dag_id}</a>'.format(**locals()))
  
  
  def log_url_formatter(v, c, m, p):
      return Markup(
          '<a href="{m.log_url}">'
          '    <span class="glyphicon glyphicon-book" aria-hidden="true">'
          '</span></a>').format(**locals())
  
  
  def task_instance_link(v, c, m, p):
      url = url_for(
          'airflow.task',
          dag_id=m.dag_id,
          task_id=m.task_id,
          execution_date=m.execution_date.isoformat())
      url_root = url_for(
          'airflow.graph',
          dag_id=m.dag_id,
          root=m.task_id,
          execution_date=m.execution_date.isoformat())
      return Markup(
          """
          <span style="white-space: nowrap;">
          <a href="{url}">{m.task_id}</a>
          <a href="{url_root}" title="Filter on this task and upstream">
          <span class="glyphicon glyphicon-filter" style="margin-left: 0px;"
              aria-hidden="true"></span>
          </a>
          </span>
          """.format(**locals()))
  
  
  def state_token(state):
      color = State.color(state)
      return Markup(
          '<span class="label" style="background-color:{color};">'
          '{state}</span>'.format(**locals()))
  
  
  def state_f(v, c, m, p):
      return state_token(m.state)
  
  
  def duration_f(v, c, m, p):
      if m.end_date and m.duration:
          return timedelta(seconds=m.duration)
  
  
  def datetime_f(v, c, m, p):
      attr = getattr(m, p)
      dttm = attr.isoformat() if attr else ''
      if datetime.now().isoformat()[:4] == dttm[:4]:
          dttm = dttm[5:]
      return Markup("<nobr>{}</nobr>".format(dttm))
  
  
  def nobr_f(v, c, m, p):
      return Markup("<nobr>{}</nobr>".format(getattr(m, p)))
  
  
  def label_link(v, c, m, p):
      try:
          default_params = ast.literal_eval(m.default_params)
      except:
          default_params = {}
      url = url_for(
          'airflow.chart', chart_id=m.id, iteration_no=m.iteration_no,
          **default_params)
      return Markup("<a href='{url}'>{m.label}</a>".format(**locals()))
  
  
  def pool_link(v, c, m, p):
      url = '/admin/taskinstance/?flt1_pool_equals=' + m.pool
      return Markup("<a href='{url}'>{m.pool}</a>".format(**locals()))
  
  
  def pygment_html_render(s, lexer=lexers.TextLexer):
      return highlight(
          s,
          lexer(),
          HtmlFormatter(linenos=True),
      )
  
  
  def render(obj, lexer):
      out = ""
      if isinstance(obj, basestring):
          out += pygment_html_render(obj, lexer)
      elif isinstance(obj, (tuple, list)):
          for i, s in enumerate(obj):
              out += "<div>List item #{}</div>".format(i)
              out += "<div>" + pygment_html_render(s, lexer) + "</div>"
      elif isinstance(obj, dict):
          for k, v in obj.items():
              out += '<div>Dict item "{}"</div>'.format(k)
              out += "<div>" + pygment_html_render(v, lexer) + "</div>"
      return out
  
  
  def wrapped_markdown(s):
      return '<div class="rich_doc">' + markdown.markdown(s) + "</div>"
  
  
  attr_renderer = {
      'bash_command': lambda x: render(x, lexers.BashLexer),
      'hql': lambda x: render(x, lexers.SqlLexer),
      'sql': lambda x: render(x, lexers.SqlLexer),
      'doc': lambda x: render(x, lexers.TextLexer),
      'doc_json': lambda x: render(x, lexers.JsonLexer),
      'doc_rst': lambda x: render(x, lexers.RstLexer),
      'doc_yaml': lambda x: render(x, lexers.YamlLexer),
      'doc_md': wrapped_markdown,
      'python_callable': lambda x: render(
          inspect.getsource(x), lexers.PythonLexer),
  }
  
  
  def data_profiling_required(f):
      '''
      Decorator for views requiring data profiling access
      '''
      @wraps(f)
      def decorated_function(*args, **kwargs):
          if (
                      current_app.config['LOGIN_DISABLED'] or
                      (not current_user.is_anonymous() and current_user.data_profiling())
          ):
              return f(*args, **kwargs)
          else:
              flash("This page requires data profiling privileges", "error")
              return redirect(url_for('admin.index'))
      return decorated_function
  
  
  def fused_slots(v, c, m, p):
      url = (
          '/admin/taskinstance/' +
          '?flt1_pool_equals=' + m.pool +
          '&flt2_state_equals=running')
      return Markup("<a href='{0}'>{1}</a>".format(url, m.used_slots()))
  
  
  def fqueued_slots(v, c, m, p):
      url = (
          '/admin/taskinstance/' +
          '?flt1_pool_equals=' + m.pool +
          '&flt2_state_equals=queued&sort=10&desc=1')
      return Markup("<a href='{0}'>{1}</a>".format(url, m.queued_slots()))
  
  
  def recurse_tasks(tasks, task_ids, dag_ids, task_id_to_dag):
      if isinstance(tasks, list):
          for task in tasks:
              recurse_tasks(task, task_ids, dag_ids, task_id_to_dag)
          return
      if isinstance(tasks, SubDagOperator):
          subtasks = tasks.subdag.tasks
          dag_ids.append(tasks.subdag.dag_id)
          for subtask in subtasks:
              if subtask.task_id not in task_ids:
                  task_ids.append(subtask.task_id)
                  task_id_to_dag[subtask.task_id] = tasks.subdag
          recurse_tasks(subtasks, task_ids, dag_ids, task_id_to_dag)
      if isinstance(tasks, BaseOperator):
          task_id_to_dag[tasks.task_id] = tasks.dag
  
  
  def should_hide_value_for_key(key_name):
      return any(s in key_name for s in DEFAULT_SENSITIVE_VARIABLE_FIELDS) \
             and conf.getboolean('admin', 'hide_sensitive_variable_fields')
  
  
  class Airflow(BaseView):
  
      def is_visible(self):
          return False
  
      @expose('/')
      @login_required
      def index(self):
          return self.render('airflow/dags.html')
  
      @expose('/chart_data')
      @data_profiling_required
      @wwwutils.gzipped
      # @cache.cached(timeout=3600, key_prefix=wwwutils.make_cache_key)
      def chart_data(self):
          from airflow import macros
          import pandas as pd
          session = settings.Session()
          chart_id = request.args.get('chart_id')
          csv = request.args.get('csv') == "true"
          chart = session.query(models.Chart).filter_by(id=chart_id).first()
          db = session.query(
              models.Connection).filter_by(conn_id=chart.conn_id).first()
          session.expunge_all()
          session.commit()
          session.close()
  
          payload = {}
          payload['state'] = 'ERROR'
          payload['error'] = ''
  
          # Processing templated fields
          try:
              args = eval(chart.default_params)
              if type(args) is not type(dict()):
                  raise AirflowException('Not a dict')
          except:
              args = {}
              payload['error'] += (
                  "Default params is not valid, string has to evaluate as "
                  "a Python dictionary. ")
  
          request_dict = {k: request.args.get(k) for k in request.args}
          args.update(request_dict)
          args['macros'] = macros
          sql = jinja2.Template(chart.sql).render(**args)
          label = jinja2.Template(chart.label).render(**args)
          payload['sql_html'] = Markup(highlight(
              sql,
              lexers.SqlLexer(),  # Lexer call
              HtmlFormatter(noclasses=True))
          )
          payload['label'] = label
  
          pd.set_option('display.max_colwidth', 100)
          hook = db.get_hook()
          try:
              df = hook.get_pandas_df(
                  wwwutils.limit_sql(sql, CHART_LIMIT, conn_type=db.conn_type))
              df = df.fillna(0)
          except Exception as e:
              payload['error'] += "SQL execution failed. Details: " + str(e)
  
          if csv:
              return Response(
                  response=df.to_csv(index=False),
                  status=200,
                  mimetype="application/text")
  
          if not payload['error'] and len(df) == CHART_LIMIT:
              payload['warning'] = (
                  "Data has been truncated to {0}"
                  " rows. Expect incomplete results.").format(CHART_LIMIT)
  
          if not payload['error'] and len(df) == 0:
              payload['error'] += "Empty result set. "
          elif (
                  not payload['error'] and
                  chart.sql_layout == 'series' and
                  chart.chart_type != "datatable" and
                  len(df.columns) < 3):
              payload['error'] += "SQL needs to return at least 3 columns. "
          elif (
                  not payload['error'] and
                  chart.sql_layout == 'columns'and
                  len(df.columns) < 2):
              payload['error'] += "SQL needs to return at least 2 columns. "
          elif not payload['error']:
              import numpy as np
              chart_type = chart.chart_type
  
              data = None
              if chart.show_datatable or chart_type == "datatable":
                  data = df.to_dict(orient="split")
                  data['columns'] = [{'title': c} for c in data['columns']]
                  payload['data'] = data
  
              # Trying to convert time to something Highcharts likes
              x_col = 1 if chart.sql_layout == 'series' else 0
              if chart.x_is_date:
                  try:
                      # From string to datetime
                      df[df.columns[x_col]] = pd.to_datetime(
                          df[df.columns[x_col]])
                      df[df.columns[x_col]] = df[df.columns[x_col]].apply(
                          lambda x: int(x.strftime("%s")) * 1000)
                  except Exception as e:
                      payload['error'] = "Time conversion failed"
  
              if chart_type == 'datatable':
                  payload['state'] = 'SUCCESS'
                  return wwwutils.json_response(payload)
              else:
                  if chart.sql_layout == 'series':
                      # User provides columns (series, x, y)
                      xaxis_label = df.columns[1]
                      yaxis_label = df.columns[2]
                      df[df.columns[2]] = df[df.columns[2]].astype(np.float)
                      df = df.pivot_table(
                          index=df.columns[1],
                          columns=df.columns[0],
                          values=df.columns[2], aggfunc=np.sum)
                  else:
                      # User provides columns (x, y, metric1, metric2, ...)
                      xaxis_label = df.columns[0]
                      yaxis_label = 'y'
                      df.index = df[df.columns[0]]
                      df = df.sort(df.columns[0])
                      del df[df.columns[0]]
                      for col in df.columns:
                          df[col] = df[col].astype(np.float)
  
                  df = df.fillna(0)
                  NVd3ChartClass = chart_mapping.get(chart.chart_type)
                  NVd3ChartClass = getattr(nvd3, NVd3ChartClass)
                  nvd3_chart = NVd3ChartClass(x_is_date=chart.x_is_date)
  
                  for col in df.columns:
                      nvd3_chart.add_serie(name=col, y=df[col].tolist(), x=df[col].index.tolist())
                  try:
                      nvd3_chart.buildcontent()
                      payload['chart_type'] = nvd3_chart.__class__.__name__
                      payload['htmlcontent'] = nvd3_chart.htmlcontent
                  except Exception as e:
                      payload['error'] = str(e)
  
              payload['state'] = 'SUCCESS'
              payload['request_dict'] = request_dict
          return wwwutils.json_response(payload)
  
      @expose('/chart')
      @data_profiling_required
      def chart(self):
          session = settings.Session()
          chart_id = request.args.get('chart_id')
          embed = request.args.get('embed')
          chart = session.query(models.Chart).filter_by(id=chart_id).first()
          session.expunge_all()
          session.commit()
          session.close()
  
          NVd3ChartClass = chart_mapping.get(chart.chart_type)
          if not NVd3ChartClass:
              flash(
                  "Not supported anymore as the license was incompatible, "
                  "sorry",
                  "danger")
              redirect('/admin/chart/')
  
          sql = ""
          if chart.show_sql:
              sql = Markup(highlight(
                  chart.sql,
                  lexers.SqlLexer(),  # Lexer call
                  HtmlFormatter(noclasses=True))
              )
          return self.render(
              'airflow/nvd3.html',
              chart=chart,
              title="Airflow - Chart",
              sql=sql,
              label=chart.label,
              embed=embed)
  
      @expose('/dag_stats')
      def dag_stats(self):
          ds = models.DagStat
          session = Session()
  
          qry = (
              session.query(ds.dag_id, ds.state, ds.count)
          )
  
          data = {}
          for dag_id, state, count in qry:
              if dag_id not in data:
                  data[dag_id] = {}
              data[dag_id][state] = count
  
          payload = {}
          for dag in dagbag.dags.values():
              payload[dag.safe_dag_id] = []
              for state in State.dag_states:
                  try:
                      count = data[dag.dag_id][state]
                  except Exception:
                      count = 0
                  d = {
                      'state': state,
                      'count': count,
                      'dag_id': dag.dag_id,
                      'color': State.color(state)
                  }
                  payload[dag.safe_dag_id].append(d)
          return wwwutils.json_response(payload)
  
      @expose('/task_stats')
      def task_stats(self):
          TI = models.TaskInstance
          DagRun = models.DagRun
          Dag = models.DagModel
          session = Session()
  
          LastDagRun = (
              session.query(DagRun.dag_id, sqla.func.max(DagRun.execution_date).label('execution_date'))
              .join(Dag, Dag.dag_id == DagRun.dag_id)
              .filter(DagRun.state != State.RUNNING)
              .filter(Dag.is_active == True)
              .group_by(DagRun.dag_id)
              .subquery('last_dag_run')
          )
          RunningDagRun = (
              session.query(DagRun.dag_id, DagRun.execution_date)
              .join(Dag, Dag.dag_id == DagRun.dag_id)
              .filter(DagRun.state == State.RUNNING)
              .filter(Dag.is_active == True)
              .subquery('running_dag_run')
          )
  
          # Select all task_instances from active dag_runs.
          # If no dag_run is active, return task instances from most recent dag_run.
          LastTI = (
              session.query(TI.dag_id.label('dag_id'), TI.state.label('state'))
              .join(LastDagRun, and_(
                  LastDagRun.c.dag_id == TI.dag_id,
                  LastDagRun.c.execution_date == TI.execution_date))
          )
          RunningTI = (
              session.query(TI.dag_id.label('dag_id'), TI.state.label('state'))
              .join(RunningDagRun, and_(
                  RunningDagRun.c.dag_id == TI.dag_id,
                  RunningDagRun.c.execution_date == TI.execution_date))
          )
  
          UnionTI = union_all(LastTI, RunningTI).alias('union_ti')
          qry = (
              session.query(UnionTI.c.dag_id, UnionTI.c.state, sqla.func.count())
              .group_by(UnionTI.c.dag_id, UnionTI.c.state)
          )
  
          data = {}
          for dag_id, state, count in qry:
              if dag_id not in data:
                  data[dag_id] = {}
              data[dag_id][state] = count
          session.commit()
          session.close()
  
          payload = {}
          for dag in dagbag.dags.values():
              payload[dag.safe_dag_id] = []
              for state in State.task_states:
                  try:
                      count = data[dag.dag_id][state]
                  except:
                      count = 0
                  d = {
                      'state': state,
                      'count': count,
                      'dag_id': dag.dag_id,
                      'color': State.color(state)
                  }
                  payload[dag.safe_dag_id].append(d)
          return wwwutils.json_response(payload)
  
      @expose('/code')
      @login_required
      def code(self):
          dag_id = request.args.get('dag_id')
          dag = dagbag.get_dag(dag_id)
          title = dag_id
          try:
              with open(dag.fileloc, 'r') as f:
                  code = f.read()
              html_code = highlight(
                  code, lexers.PythonLexer(), HtmlFormatter(linenos=True))
          except IOError as e:
              html_code = str(e)
  
          return self.render(
              'airflow/dag_code.html', html_code=html_code, dag=dag, title=title,
              root=request.args.get('root'),
              demo_mode=conf.getboolean('webserver', 'demo_mode'))
  
      @expose('/dag_details')
      @login_required
      def dag_details(self):
          dag_id = request.args.get('dag_id')
          dag = dagbag.get_dag(dag_id)
          title = "DAG details"
  
          session = settings.Session()
          TI = models.TaskInstance
          states = (
              session.query(TI.state, sqla.func.count(TI.dag_id))
              .filter(TI.dag_id == dag_id)
              .group_by(TI.state)
              .all()
          )
          return self.render(
              'airflow/dag_details.html',
              dag=dag, title=title, states=states, State=State)
  
      @current_app.errorhandler(404)
      def circles(self):
          return render_template(
              'airflow/circles.html', hostname=socket.getfqdn()), 404
  
      @current_app.errorhandler(500)
      def show_traceback(self):
          from airflow.utils import asciiart as ascii_
          return render_template(
              'airflow/traceback.html',
              hostname=socket.getfqdn(),
              nukular=ascii_.nukular,
              info=traceback.format_exc()), 500
  
      @expose('/noaccess')
      def noaccess(self):
          return self.render('airflow/noaccess.html')
  
      @expose('/headers')
      def headers(self):
          d = {
              'headers': {k: v for k, v in request.headers},
          }
          if hasattr(current_user, 'is_superuser'):
              d['is_superuser'] = current_user.is_superuser()
              d['data_profiling'] = current_user.data_profiling()
              d['is_anonymous'] = current_user.is_anonymous()
              d['is_authenticated'] = current_user.is_authenticated()
          if hasattr(current_user, 'username'):
              d['username'] = current_user.username
          return wwwutils.json_response(d)
  
      @expose('/pickle_info')
      @login_required
      def pickle_info(self):
          d = {}
          dag_id = request.args.get('dag_id')
          dags = [dagbag.dags.get(dag_id)] if dag_id else dagbag.dags.values()
          for dag in dags:
              if not dag.is_subdag:
                  d[dag.dag_id] = dag.pickle_info()
          return wwwutils.json_response(d)
  
      @expose('/login', methods=['GET', 'POST'])
      def login(self):
          return airflow.login.login(self, request)
  
      @expose('/logout')
      def logout(self):
          logout_user()
          flash('You have been logged out.')
          return redirect(url_for('admin.index'))
  
      @expose('/rendered')
      @login_required
      @wwwutils.action_logging
      def rendered(self):
          dag_id = request.args.get('dag_id')
          task_id = request.args.get('task_id')
          execution_date = request.args.get('execution_date')
          dttm = dateutil.parser.parse(execution_date)
          form = DateTimeForm(data={'execution_date': dttm})
          dag = dagbag.get_dag(dag_id)
          task = copy.copy(dag.get_task(task_id))
          ti = models.TaskInstance(task=task, execution_date=dttm)
          try:
              ti.render_templates()
          except Exception as e:
              flash("Error rendering template: " + str(e), "error")
          title = "Rendered Template"
          html_dict = {}
          for template_field in task.__class__.template_fields:
              content = getattr(task, template_field)
              if template_field in attr_renderer:
                  html_dict[template_field] = attr_renderer[template_field](content)
              else:
                  html_dict[template_field] = (
                      "<pre><code>" + str(content) + "</pre></code>")
  
          return self.render(
              'airflow/ti_code.html',
              html_dict=html_dict,
              dag=dag,
              task_id=task_id,
              execution_date=execution_date,
              form=form,
              title=title,)
  
      @expose('/log')
      @login_required
      @wwwutils.action_logging
      def log(self):
          BASE_LOG_FOLDER = os.path.expanduser(
              conf.get('core', 'BASE_LOG_FOLDER'))
          dag_id = request.args.get('dag_id')
          task_id = request.args.get('task_id')
          execution_date = request.args.get('execution_date')
          dag = dagbag.get_dag(dag_id)
          log_relative = "{dag_id}/{task_id}/{execution_date}".format(
              **locals())
          loc = os.path.join(BASE_LOG_FOLDER, log_relative)
          loc = loc.format(**locals())
          log = ""
          TI = models.TaskInstance
          session = Session()
          dttm = dateutil.parser.parse(execution_date)
          ti = session.query(TI).filter(
              TI.dag_id == dag_id, TI.task_id == task_id,
              TI.execution_date == dttm).first()
          dttm = dateutil.parser.parse(execution_date)
          form = DateTimeForm(data={'execution_date': dttm})
  
          if ti:
              host = ti.hostname
              log_loaded = False
  
              if os.path.exists(loc):
                  try:
                      f = open(loc)
                      log += "".join(f.readlines())
                      f.close()
                      log_loaded = True
                  except:
                      log = "*** Failed to load local log file: {0}.\n".format(loc)
              else:
                  WORKER_LOG_SERVER_PORT = \
                      conf.get('celery', 'WORKER_LOG_SERVER_PORT')
                  url = os.path.join(
                      "http://{host}:{WORKER_LOG_SERVER_PORT}/log", log_relative
                      ).format(**locals())
                  log += "*** Log file isn't local.\n"
                  log += "*** Fetching here: {url}\n".format(**locals())
                  try:
                      import requests
                      timeout = None  # No timeout
                      try:
                          timeout = conf.getint('webserver', 'log_fetch_timeout_sec')
                      except (AirflowConfigException, ValueError):
                          pass
  
                      response = requests.get(url, timeout=timeout)
                      response.raise_for_status()
                      log += '\n' + response.text
                      log_loaded = True
                  except:
                      log += "*** Failed to fetch log file from worker.\n".format(
                          **locals())
  
              if not log_loaded:
                  # load remote logs
                  remote_log_base = conf.get('core', 'REMOTE_BASE_LOG_FOLDER')
                  remote_log = os.path.join(remote_log_base, log_relative)
                  log += '\n*** Reading remote logs...\n'
  
                  # S3
                  if remote_log.startswith('s3:/'):
                      log += log_utils.S3Log().read(remote_log, return_error=True)
  
                  # GCS
                  elif remote_log.startswith('gs:/'):
                      log += log_utils.GCSLog().read(remote_log, return_error=True)
  
                  # unsupported
                  elif remote_log:
                      log += '*** Unsupported remote log location.'
  
              session.commit()
              session.close()
  
          if PY2 and not isinstance(log, unicode):
              log = log.decode('utf-8')
  
          title = "Log"
  
          return self.render(
              'airflow/ti_code.html',
              code=log, dag=dag, title=title, task_id=task_id,
              execution_date=execution_date, form=form)
  
      @expose('/task')
      @login_required
      @wwwutils.action_logging
      def task(self):
          TI = models.TaskInstance
  
          dag_id = request.args.get('dag_id')
          task_id = request.args.get('task_id')
          # Carrying execution_date through, even though it's irrelevant for
          # this context
          execution_date = request.args.get('execution_date')
          dttm = dateutil.parser.parse(execution_date)
          form = DateTimeForm(data={'execution_date': dttm})
          dag = dagbag.get_dag(dag_id)
  
          if not dag or task_id not in dag.task_ids:
              flash(
                  "Task [{}.{}] doesn't seem to exist"
                  " at the moment".format(dag_id, task_id),
                  "error")
              return redirect('/admin/')
          task = copy.copy(dag.get_task(task_id))
          task.resolve_template_files()
          ti = TI(task=task, execution_date=dttm)
          ti.refresh_from_db()
  
          ti_attrs = []
          for attr_name in dir(ti):
              if not attr_name.startswith('_'):
                  attr = getattr(ti, attr_name)
                  if type(attr) != type(self.task):
                      ti_attrs.append((attr_name, str(attr)))
  
          task_attrs = []
          for attr_name in dir(task):
              if not attr_name.startswith('_'):
                  attr = getattr(task, attr_name)
                  if type(attr) != type(self.task) and \
                                  attr_name not in attr_renderer:
                      task_attrs.append((attr_name, str(attr)))
  
          # Color coding the special attributes that are code
          special_attrs_rendered = {}
          for attr_name in attr_renderer:
              if hasattr(task, attr_name):
                  source = getattr(task, attr_name)
                  special_attrs_rendered[attr_name] = attr_renderer[attr_name](source)
  
          no_failed_deps_result = [(
              "Unknown",
              dedent("""\
              All dependencies are met but the task instance is not running. In most cases this just means that the task will probably be scheduled soon unless:<br/>
              - The scheduler is down or under heavy load<br/>
              {}
              <br/>
              If this task instance does not start soon please contact your Airflow administrator for assistance."""
                     .format(
                         "- This task instance already ran and had it's state changed manually (e.g. cleared in the UI)<br/>"
                         if ti.state == State.NONE else "")))]
  
          # Use the scheduler's context to figure out which dependencies are not met
          dep_context = DepContext(SCHEDULER_DEPS)
          failed_dep_reasons = [(dep.dep_name, dep.reason) for dep in
                                ti.get_failed_dep_statuses(
                                    dep_context=dep_context)]
  
          title = "Task Instance Details"
          return self.render(
              'airflow/task.html',
              task_attrs=task_attrs,
              ti_attrs=ti_attrs,
              failed_dep_reasons=failed_dep_reasons or no_failed_deps_result,
              task_id=task_id,
              execution_date=execution_date,
              special_attrs_rendered=special_attrs_rendered,
              form=form,
              dag=dag, title=title)
  
      @expose('/xcom')
      @login_required
      @wwwutils.action_logging
      def xcom(self):
          dag_id = request.args.get('dag_id')
          task_id = request.args.get('task_id')
          # Carrying execution_date through, even though it's irrelevant for
          # this context
          execution_date = request.args.get('execution_date')
          dttm = dateutil.parser.parse(execution_date)
          form = DateTimeForm(data={'execution_date': dttm})
          dag = dagbag.get_dag(dag_id)
          if not dag or task_id not in dag.task_ids:
              flash(
                  "Task [{}.{}] doesn't seem to exist"
                  " at the moment".format(dag_id, task_id),
                  "error")
              return redirect('/admin/')
  
          session = Session()
          xcomlist = session.query(XCom).filter(
              XCom.dag_id == dag_id, XCom.task_id == task_id,
              XCom.execution_date == dttm).all()
  
          attributes = []
          for xcom in xcomlist:
              if not xcom.key.startswith('_'):
                  attributes.append((xcom.key, xcom.value))
  
          title = "XCom"
          return self.render(
              'airflow/xcom.html',
              attributes=attributes,
              task_id=task_id,
              execution_date=execution_date,
              form=form,
              dag=dag, title=title)
  
      @expose('/run')
      @login_required
      @wwwutils.action_logging
      @wwwutils.notify_owner
      def run(self):
          dag_id = request.args.get('dag_id')
          task_id = request.args.get('task_id')
          origin = request.args.get('origin')
          dag = dagbag.get_dag(dag_id)
          task = dag.get_task(task_id)
  
          execution_date = request.args.get('execution_date')
          execution_date = dateutil.parser.parse(execution_date)
          ignore_all_deps = request.args.get('ignore_all_deps') == "true"
          ignore_task_deps = request.args.get('ignore_task_deps') == "true"
          ignore_ti_state = request.args.get('ignore_ti_state') == "true"
  
          try:
              from airflow.executors import DEFAULT_EXECUTOR as executor
              from airflow.executors import CeleryExecutor
              if not isinstance(executor, CeleryExecutor):
                  flash("Only works with the CeleryExecutor, sorry", "error")
                  return redirect(origin)
          except ImportError:
              # in case CeleryExecutor cannot be imported it is not active either
              flash("Only works with the CeleryExecutor, sorry", "error")
              return redirect(origin)
  
          ti = models.TaskInstance(task=task, execution_date=execution_date)
          ti.refresh_from_db()
  
          # Make sure the task instance can be queued
          dep_context = DepContext(
              deps=QUEUE_DEPS,
              ignore_all_deps=ignore_all_deps,
              ignore_task_deps=ignore_task_deps,
              ignore_ti_state=ignore_ti_state)
          failed_deps = list(ti.get_failed_dep_statuses(dep_context=dep_context))
          if failed_deps:
              failed_deps_str = ", ".join(
                  ["{}: {}".format(dep.dep_name, dep.reason) for dep in failed_deps])
              flash("Could not queue task instance for execution, dependencies not met: "
                    "{}".format(failed_deps_str),
                    "error")
              return redirect(origin)
  
          executor.start()
          executor.queue_task_instance(
              ti,
              ignore_all_deps=ignore_all_deps,
              ignore_task_deps=ignore_task_deps,
              ignore_ti_state=ignore_ti_state)
          executor.heartbeat()
          flash(
              "Sent {} to the message queue, "
              "it should start any moment now.".format(ti))
          return redirect(origin)
  
      @expose('/trigger')
      @login_required
      @wwwutils.action_logging
      @wwwutils.notify_owner
      def trigger(self):
          dag_id = request.args.get('dag_id')
          origin = request.args.get('origin') or "/admin/"
          dag = dagbag.get_dag(dag_id)
  
          if not dag:
              flash("Cannot find dag {}".format(dag_id))
              return redirect(origin)
  
          execution_date = datetime.now()
          run_id = "manual__{0}".format(execution_date.isoformat())
  
          dr = DagRun.find(dag_id=dag_id, run_id=run_id)
          if dr:
              flash("This run_id {} already exists".format(run_id))
              return redirect(origin)
  
          run_conf = {}
  
          dag.create_dagrun(
              run_id=run_id,
              execution_date=execution_date,
              state=State.RUNNING,
              conf=run_conf,
              external_trigger=True
          )
  
          flash(
              "Triggered {}, "
              "it should start any moment now.".format(dag_id))
          return redirect(origin)
  
      @expose('/clear')
      @login_required
      @wwwutils.action_logging
      @wwwutils.notify_owner
      def clear(self):
          dag_id = request.args.get('dag_id')
          task_id = request.args.get('task_id')
          origin = request.args.get('origin')
          dag = dagbag.get_dag(dag_id)
  
          execution_date = request.args.get('execution_date')
          execution_date = dateutil.parser.parse(execution_date)
          confirmed = request.args.get('confirmed') == "true"
          upstream = request.args.get('upstream') == "true"
          downstream = request.args.get('downstream') == "true"
          future = request.args.get('future') == "true"
          past = request.args.get('past') == "true"
          recursive = request.args.get('recursive') == "true"
  
          dag = dag.sub_dag(
              task_regex=r"^{0}$".format(task_id),
              include_downstream=downstream,
              include_upstream=upstream)
  
          end_date = execution_date if not future else None
          start_date = execution_date if not past else None
          if confirmed:
              count = dag.clear(
                  start_date=start_date,
                  end_date=end_date,
                  include_subdags=recursive)
  
              flash("{0} task instances have been cleared".format(count))
              return redirect(origin)
          else:
              tis = dag.clear(
                  start_date=start_date,
                  end_date=end_date,
                  include_subdags=recursive,
                  dry_run=True)
              if not tis:
                  flash("No task instances to clear", 'error')
                  response = redirect(origin)
              else:
                  details = "\n".join([str(t) for t in tis])
  
                  response = self.render(
                      'airflow/confirm.html',
                      message=(
                          "Here's the list of task instances you are about "
                          "to clear:"),
                      details=details,)
  
              return response
  
      @expose('/blocked')
      @login_required
      def blocked(self):
          session = settings.Session()
          DR = models.DagRun
          dags = (
              session.query(DR.dag_id, sqla.func.count(DR.id))
              .filter(DR.state == State.RUNNING)
              .group_by(DR.dag_id)
              .all()
          )
          payload = []
          for dag_id, active_dag_runs in dags:
              max_active_runs = 0
              if dag_id in dagbag.dags:
                  max_active_runs = dagbag.dags[dag_id].max_active_runs
              payload.append({
                  'dag_id': dag_id,
                  'active_dag_run': active_dag_runs,
                  'max_active_runs': max_active_runs,
              })
          return wwwutils.json_response(payload)
  
      @expose('/success')
      @login_required
      @wwwutils.action_logging
      @wwwutils.notify_owner
      def success(self):
          dag_id = request.args.get('dag_id')
          task_id = request.args.get('task_id')
          origin = request.args.get('origin')
          dag = dagbag.get_dag(dag_id)
          task = dag.get_task(task_id)
          task.dag = dag
  
          execution_date = request.args.get('execution_date')
          execution_date = dateutil.parser.parse(execution_date)
          confirmed = request.args.get('confirmed') == "true"
          upstream = request.args.get('upstream') == "true"
          downstream = request.args.get('downstream') == "true"
          future = request.args.get('future') == "true"
          past = request.args.get('past') == "true"
  
          if not dag:
              flash("Cannot find DAG: {}".format(dag_id))
              return redirect(origin)
  
          if not task:
              flash("Cannot find task {} in DAG {}".format(task_id, dag.dag_id))
              return redirect(origin)
  
          from airflow.api.common.experimental.mark_tasks import set_state
  
          if confirmed:
              altered = set_state(task=task, execution_date=execution_date,
                                  upstream=upstream, downstream=downstream,
                                  future=future, past=past, state=State.SUCCESS,
                                  commit=True)
  
              flash("Marked success on {} task instances".format(len(altered)))
              return redirect(origin)
  
          to_be_altered = set_state(task=task, execution_date=execution_date,
                                    upstream=upstream, downstream=downstream,
                                    future=future, past=past, state=State.SUCCESS,
                                    commit=False)
  
          details = "\n".join([str(t) for t in to_be_altered])
  
          response = self.render("airflow/confirm.html",
                                 message=("Here's the list of task instances you are "
                                          "about to mark as successful:"),
                                 details=details)
  
          return response
  
      @expose('/tree')
      @login_required
      @wwwutils.gzipped
      @wwwutils.action_logging
      def tree(self):
          dag_id = request.args.get('dag_id')
          blur = conf.getboolean('webserver', 'demo_mode')
          dag = dagbag.get_dag(dag_id)
          root = request.args.get('root')
          if root:
              dag = dag.sub_dag(
                  task_regex=root,
                  include_downstream=False,
                  include_upstream=True)
  
          session = settings.Session()
  
          base_date = request.args.get('base_date')
          num_runs = request.args.get('num_runs')
          num_runs = int(num_runs) if num_runs else 25
  
          if base_date:
              base_date = dateutil.parser.parse(base_date)
          else:
              base_date = dag.latest_execution_date or datetime.now()
  
          dates = dag.date_range(base_date, num=-abs(num_runs))
          min_date = dates[0] if dates else datetime(2000, 1, 1)
  
          DR = models.DagRun
          dag_runs = (
              session.query(DR)
              .filter(
                  DR.dag_id==dag.dag_id,
                  DR.execution_date<=base_date,
                  DR.execution_date>=min_date)
              .all()
          )
          dag_runs = {
              dr.execution_date: alchemy_to_dict(dr) for dr in dag_runs}
  
          dates = sorted(list(dag_runs.keys()))
          max_date = max(dates) if dates else None
  
          tis = dag.get_task_instances(
                  session, start_date=min_date, end_date=base_date)
          task_instances = {}
          for ti in tis:
              tid = alchemy_to_dict(ti)
              dr = dag_runs.get(ti.execution_date)
              tid['external_trigger'] = dr['external_trigger'] if dr else False
              task_instances[(ti.task_id, ti.execution_date)] = tid
  
          expanded = []
          # The default recursion traces every path so that tree view has full
          # expand/collapse functionality. After 5,000 nodes we stop and fall
          # back on a quick DFS search for performance. See PR #320.
          node_count = [0]
          node_limit = 5000 / max(1, len(dag.roots))
  
          def recurse_nodes(task, visited):
              visited.add(task)
              node_count[0] += 1
  
              children = [
                  recurse_nodes(t, visited) for t in task.upstream_list
                  if node_count[0] < node_limit or t not in visited]
  
              # D3 tree uses children vs _children to define what is
              # expanded or not. The following block makes it such that
              # repeated nodes are collapsed by default.
              children_key = 'children'
              if task.task_id not in expanded:
                  expanded.append(task.task_id)
              elif children:
                  children_key = "_children"
  
              def set_duration(tid):
                  if (isinstance(tid, dict) and tid.get("state") == State.RUNNING and
                          tid["start_date"] is not None):
                      d = datetime.now() - dateutil.parser.parse(tid["start_date"])
                      tid["duration"] = d.total_seconds()
                  return tid
  
              return {
                  'name': task.task_id,
                  'instances': [
                          set_duration(task_instances.get((task.task_id, d))) or {
                              'execution_date': d.isoformat(),
                              'task_id': task.task_id
                          }
                      for d in dates],
                  children_key: children,
                  'num_dep': len(task.upstream_list),
                  'operator': task.task_type,
                  'retries': task.retries,
                  'owner': task.owner,
                  'start_date': task.start_date,
                  'end_date': task.end_date,
                  'depends_on_past': task.depends_on_past,
                  'ui_color': task.ui_color,
              }
          data = {
              'name': '[DAG]',
              'children': [recurse_nodes(t, set()) for t in dag.roots],
              'instances': [
                  dag_runs.get(d) or {'execution_date': d.isoformat()}
                  for d in dates],
          }
  
          data = json.dumps(data, indent=4, default=json_ser)
          session.commit()
          session.close()
  
          form = DateTimeWithNumRunsForm(data={'base_date': max_date,
                                               'num_runs': num_runs})
          return self.render(
              'airflow/tree.html',
              operators=sorted(
                  list(set([op.__class__ for op in dag.tasks])),
                  key=lambda x: x.__name__
              ),
              root=root,
              form=form,
              dag=dag, data=data, blur=blur)
  
      @expose('/graph')
      @login_required
      @wwwutils.gzipped
      @wwwutils.action_logging
      def graph(self):
          session = settings.Session()
          dag_id = request.args.get('dag_id')
          blur = conf.getboolean('webserver', 'demo_mode')
          dag = dagbag.get_dag(dag_id)
          if dag_id not in dagbag.dags:
              flash('DAG "{0}" seems to be missing.'.format(dag_id), "error")
              return redirect('/admin/')
  
          root = request.args.get('root')
          if root:
              dag = dag.sub_dag(
                  task_regex=root,
                  include_upstream=True,
                  include_downstream=False)
  
          arrange = request.args.get('arrange', dag.orientation)
  
          nodes = []
          edges = []
          for task in dag.tasks:
              nodes.append({
                  'id': task.task_id,
                  'value': {
                      'label': task.task_id,
                      'labelStyle': "fill:{0};".format(task.ui_fgcolor),
                      'style': "fill:{0};".format(task.ui_color),
                  }
              })
  
          def get_upstream(task):
              for t in task.upstream_list:
                  edge = {
                      'u': t.task_id,
                      'v': task.task_id,
                  }
                  if edge not in edges:
                      edges.append(edge)
                      get_upstream(t)
  
          for t in dag.roots:
              get_upstream(t)
  
          dttm = request.args.get('execution_date')
          if dttm:
              dttm = dateutil.parser.parse(dttm)
          else:
              dttm = dag.latest_execution_date or datetime.now().date()
  
          DR = models.DagRun
          drs = (
              session.query(DR)
              .filter_by(dag_id=dag_id)
              .order_by(desc(DR.execution_date)).all()
          )
          dr_choices = []
          dr_state = None
          for dr in drs:
              dr_choices.append((dr.execution_date.isoformat(), dr.run_id))
              if dttm == dr.execution_date:
                  dr_state = dr.state
  
          class GraphForm(Form):
              execution_date = SelectField("DAG run", choices=dr_choices)
              arrange = SelectField("Layout", choices=(
                  ('LR', "Left->Right"),
                  ('RL', "Right->Left"),
                  ('TB', "Top->Bottom"),
                  ('BT', "Bottom->Top"),
              ))
          form = GraphForm(
              data={'execution_date': dttm.isoformat(), 'arrange': arrange})
  
          task_instances = {
              ti.task_id: alchemy_to_dict(ti)
              for ti in dag.get_task_instances(session, dttm, dttm)}
          tasks = {
              t.task_id: {
                  'dag_id': t.dag_id,
                  'task_type': t.task_type,
              }
              for t in dag.tasks}
          if not tasks:
              flash("No tasks found", "error")
          session.commit()
          session.close()
          doc_md = markdown.markdown(dag.doc_md) if hasattr(dag, 'doc_md') and dag.doc_md else ''
  
          return self.render(
              'airflow/graph.html',
              dag=dag,
              form=form,
              width=request.args.get('width', "100%"),
              height=request.args.get('height', "800"),
              execution_date=dttm.isoformat(),
              state_token=state_token(dr_state),
              doc_md=doc_md,
              arrange=arrange,
              operators=sorted(
                  list(set([op.__class__ for op in dag.tasks])),
                  key=lambda x: x.__name__
              ),
              blur=blur,
              root=root or '',
              task_instances=json.dumps(task_instances, indent=2),
              tasks=json.dumps(tasks, indent=2),
              nodes=json.dumps(nodes, indent=2),
              edges=json.dumps(edges, indent=2),)
  
      @expose('/duration')
      @login_required
      @wwwutils.action_logging
      def duration(self):
          session = settings.Session()
          dag_id = request.args.get('dag_id')
          dag = dagbag.get_dag(dag_id)
          base_date = request.args.get('base_date')
          num_runs = request.args.get('num_runs')
          num_runs = int(num_runs) if num_runs else 25
  
          if base_date:
              base_date = dateutil.parser.parse(base_date)
          else:
              base_date = dag.latest_execution_date or datetime.now()
  
          dates = dag.date_range(base_date, num=-abs(num_runs))
          min_date = dates[0] if dates else datetime(2000, 1, 1)
  
          root = request.args.get('root')
          if root:
              dag = dag.sub_dag(
                  task_regex=root,
                  include_upstream=True,
                  include_downstream=False)
  
          chart = nvd3.lineChart(
              name="lineChart", x_is_date=True, height=600, width="1200")
          cum_chart = nvd3.lineChart(
              name="cumLineChart", x_is_date=True, height=600, width="1200")
  
          y = {}
          x = {}
          cum_y = {}
          for task in dag.tasks:
              y[task.task_id] = []
              x[task.task_id] = []
              cum_y[task.task_id] = []
              for ti in task.get_task_instances(session, start_date=min_date,
                                                end_date=base_date):
                  if ti.duration:
                      dttm = wwwutils.epoch(ti.execution_date)
                      x[ti.task_id].append(dttm)
                      y[ti.task_id].append(float(ti.duration))
                      fails = session.query(models.TaskFail).filter_by(
                          task_id=ti.task_id,
                          dag_id=ti.dag_id,
                          execution_date=ti.execution_date).all()
                      fails_total = sum([f.duration for f in fails])
                      cum_y[ti.task_id].append(float(ti.duration + fails_total))
          # determine the most relevant time unit for the set of task instance
          # durations for the DAG
          y_unit = infer_time_unit([d for t in y.values() for d in t])
          cum_y_unit = infer_time_unit([d for t in cum_y.values() for d in t])
          # update the y Axis on both charts to have the correct time units
          chart.create_y_axis('yAxis', format='.02f', custom_format=False,
                              label='Duration ({})'.format(y_unit))
          cum_chart.create_y_axis('yAxis', format='.02f', custom_format=False,
                                  label='Duration ({})'.format(cum_y_unit))
          for task in dag.tasks:
              if x[task.task_id]:
                  chart.add_serie(name=task.task_id, x=x[task.task_id],
                                  y=scale_time_units(y[task.task_id], y_unit))
                  cum_chart.add_serie(name=task.task_id, x=x[task.task_id],
                                      y=scale_time_units(cum_y[task.task_id],
                                      cum_y_unit))
  
          tis = dag.get_task_instances(
              session, start_date=min_date, end_date=base_date)
          dates = sorted(list({ti.execution_date for ti in tis}))
          max_date = max([ti.execution_date for ti in tis]) if dates else None
  
          session.commit()
          session.close()
  
          form = DateTimeWithNumRunsForm(data={'base_date': max_date,
                                               'num_runs': num_runs})
          chart.buildcontent()
          cum_chart.buildcontent()
          s_index = cum_chart.htmlcontent.rfind('});')
          cum_chart.htmlcontent = (cum_chart.htmlcontent[:s_index]
                                   + "$( document ).trigger('chartload')"
                                   + cum_chart.htmlcontent[s_index:])
  
          return self.render(
              'airflow/duration_chart.html',
              dag=dag,
              demo_mode=conf.getboolean('webserver', 'demo_mode'),
              root=root,
              form=form,
              chart=chart.htmlcontent,
              cum_chart=cum_chart.htmlcontent
          )
  
      @expose('/tries')
      @login_required
      @wwwutils.action_logging
      def tries(self):
          session = settings.Session()
          dag_id = request.args.get('dag_id')
          dag = dagbag.get_dag(dag_id)
          base_date = request.args.get('base_date')
          num_runs = request.args.get('num_runs')
          num_runs = int(num_runs) if num_runs else 25
  
          if base_date:
              base_date = dateutil.parser.parse(base_date)
          else:
              base_date = dag.latest_execution_date or datetime.now()
  
          dates = dag.date_range(base_date, num=-abs(num_runs))
          min_date = dates[0] if dates else datetime(2000, 1, 1)
  
          root = request.args.get('root')
          if root:
              dag = dag.sub_dag(
                  task_regex=root,
                  include_upstream=True,
                  include_downstream=False)
  
          chart = nvd3.lineChart(
              name="lineChart", x_is_date=True, y_axis_format='d', height=600, width="1200")
  
          for task in dag.tasks:
              y = []
              x = []
              for ti in task.get_task_instances(session, start_date=min_date,
                                                end_date=base_date):
                  dttm = wwwutils.epoch(ti.execution_date)
                  x.append(dttm)
                  y.append(ti.try_number)
              if x:
                  chart.add_serie(name=task.task_id, x=x, y=y)
  
          tis = dag.get_task_instances(
              session, start_date=min_date, end_date=base_date)
          tries = sorted(list({ti.try_number for ti in tis}))
          max_date = max([ti.execution_date for ti in tis]) if tries else None
  
          session.commit()
          session.close()
  
          form = DateTimeWithNumRunsForm(data={'base_date': max_date,
                                               'num_runs': num_runs})
  
          chart.buildcontent()
  
          return self.render(
              'airflow/chart.html',
              dag=dag,
              demo_mode=conf.getboolean('webserver', 'demo_mode'),
              root=root,
              form=form,
              chart=chart.htmlcontent
          )
  
      @expose('/landing_times')
      @login_required
      @wwwutils.action_logging
      def landing_times(self):
          session = settings.Session()
          dag_id = request.args.get('dag_id')
          dag = dagbag.get_dag(dag_id)
          base_date = request.args.get('base_date')
          num_runs = request.args.get('num_runs')
          num_runs = int(num_runs) if num_runs else 25
  
          if base_date:
              base_date = dateutil.parser.parse(base_date)
          else:
              base_date = dag.latest_execution_date or datetime.now()
  
          dates = dag.date_range(base_date, num=-abs(num_runs))
          min_date = dates[0] if dates else datetime(2000, 1, 1)
  
          root = request.args.get('root')
          if root:
              dag = dag.sub_dag(
                  task_regex=root,
                  include_upstream=True,
                  include_downstream=False)
  
          chart = nvd3.lineChart(
              name="lineChart", x_is_date=True, height=600, width="1200")
          y = {}
          x = {}
          for task in dag.tasks:
              y[task.task_id] = []
              x[task.task_id] = []
              for ti in task.get_task_instances(session, start_date=min_date,
                                                end_date=base_date):
                  ts = ti.execution_date
                  if dag.schedule_interval:
                      ts = dag.following_schedule(ts)
                  if ti.end_date:
                      dttm = wwwutils.epoch(ti.execution_date)
                      secs = (ti.end_date - ts).total_seconds()
                      x[ti.task_id].append(dttm)
                      y[ti.task_id].append(secs)
  
          # determine the most relevant time unit for the set of landing times
          # for the DAG
          y_unit = infer_time_unit([d for t in y.values() for d in t])
          # update the y Axis to have the correct time units
          chart.create_y_axis('yAxis', format='.02f', custom_format=False,
                              label='Landing Time ({})'.format(y_unit))
          for task in dag.tasks:
              if x[task.task_id]:
                  chart.add_serie(name=task.task_id, x=x[task.task_id],
                                  y=scale_time_units(y[task.task_id], y_unit))
  
          tis = dag.get_task_instances(
                  session, start_date=min_date, end_date=base_date)
          dates = sorted(list({ti.execution_date for ti in tis}))
          max_date = max([ti.execution_date for ti in tis]) if dates else None
  
          session.commit()
          session.close()
  
          form = DateTimeWithNumRunsForm(data={'base_date': max_date,
                                               'num_runs': num_runs})
          chart.buildcontent()
          return self.render(
              'airflow/chart.html',
              dag=dag,
              chart=chart.htmlcontent,
              height="700px",
              demo_mode=conf.getboolean('webserver', 'demo_mode'),
              root=root,
              form=form,
          )
  
      @expose('/paused')
      @login_required
      @wwwutils.action_logging
      def paused(self):
          DagModel = models.DagModel
          dag_id = request.args.get('dag_id')
          session = settings.Session()
          orm_dag = session.query(
              DagModel).filter(DagModel.dag_id == dag_id).first()
          if request.args.get('is_paused') == 'false':
              orm_dag.is_paused = True
          else:
              orm_dag.is_paused = False
          session.merge(orm_dag)
          session.commit()
          session.close()
  
          dagbag.get_dag(dag_id)
          return "OK"
  
      @expose('/refresh')
      @login_required
      @wwwutils.action_logging
      def refresh(self):
          DagModel = models.DagModel
          dag_id = request.args.get('dag_id')
          session = settings.Session()
          orm_dag = session.query(
              DagModel).filter(DagModel.dag_id == dag_id).first()
  
          if orm_dag:
              orm_dag.last_expired = datetime.now()
              session.merge(orm_dag)
          session.commit()
          session.close()
  
          dagbag.get_dag(dag_id)
          flash("DAG [{}] is now fresh as a daisy".format(dag_id))
          return redirect(request.referrer)
  
      @expose('/refresh_all')
      @login_required
      @wwwutils.action_logging
      def refresh_all(self):
          dagbag.collect_dags(only_if_updated=False)
          flash("All DAGs are now up to date")
          return redirect('/')
  
      @expose('/gantt')
      @login_required
      @wwwutils.action_logging
      def gantt(self):
          session = settings.Session()
          dag_id = request.args.get('dag_id')
          dag = dagbag.get_dag(dag_id)
          demo_mode = conf.getboolean('webserver', 'demo_mode')
  
          root = request.args.get('root')
          if root:
              dag = dag.sub_dag(
                  task_regex=root,
                  include_upstream=True,
                  include_downstream=False)
  
          dttm = request.args.get('execution_date')
          if dttm:
              dttm = dateutil.parser.parse(dttm)
          else:
              dttm = dag.latest_execution_date or datetime.now().date()
  
          form = DateTimeForm(data={'execution_date': dttm})
  
          tis = [
              ti for ti in dag.get_task_instances(session, dttm, dttm)
              if ti.start_date]
          tis = sorted(tis, key=lambda ti: ti.start_date)
  
          tasks = []
          for ti in tis:
              end_date = ti.end_date if ti.end_date else datetime.now()
              tasks.append({
                  'startDate': wwwutils.epoch(ti.start_date),
                  'endDate': wwwutils.epoch(end_date),
                  'isoStart': ti.start_date.isoformat()[:-4],
                  'isoEnd': end_date.isoformat()[:-4],
                  'taskName': ti.task_id,
                  'duration': "{}".format(end_date - ti.start_date)[:-4],
                  'status': ti.state,
                  'executionDate': ti.execution_date.isoformat(),
              })
          states = {ti.state:ti.state for ti in tis}
          data = {
              'taskNames': [ti.task_id for ti in tis],
              'tasks': tasks,
              'taskStatus': states,
              'height': len(tis) * 25,
          }
  
          session.commit()
          session.close()
  
          return self.render(
              'airflow/gantt.html',
              dag=dag,
              execution_date=dttm.isoformat(),
              form=form,
              data=json.dumps(data, indent=2),
              base_date='',
              demo_mode=demo_mode,
              root=root,
          )
  
      @expose('/object/task_instances')
      @login_required
      @wwwutils.action_logging
      def task_instances(self):
          session = settings.Session()
          dag_id = request.args.get('dag_id')
          dag = dagbag.get_dag(dag_id)
  
          dttm = request.args.get('execution_date')
          if dttm:
              dttm = dateutil.parser.parse(dttm)
          else:
              return ("Error: Invalid execution_date")
  
          task_instances = {
              ti.task_id: alchemy_to_dict(ti)
              for ti in dag.get_task_instances(session, dttm, dttm)}
  
          return json.dumps(task_instances)
  
      @expose('/variables/<form>', methods=["GET", "POST"])
      @login_required
      @wwwutils.action_logging
      def variables(self, form):
          try:
              if request.method == 'POST':
                  data = request.json
                  if data:
                      session = settings.Session()
                      var = models.Variable(key=form, val=json.dumps(data))
                      session.add(var)
                      session.commit()
                  return ""
              else:
                  return self.render(
                      'airflow/variables/{}.html'.format(form)
                  )
          except:
              return ("Error: form airflow/variables/{}.html "
                      "not found.").format(form), 404
  
      @expose('/varimport', methods=["GET", "POST"])
      @login_required
      @wwwutils.action_logging
      def varimport(self):
          try:
              out = str(request.files['file'].read())
              d = json.loads(out)
          except Exception:
              flash("Missing file or syntax error.")
          else:
              for k, v in d.items():
                  models.Variable.set(k, v, serialize_json=isinstance(v, dict))
              flash("{} variable(s) successfully updated.".format(len(d)))
          return redirect('/admin/variable')
  
  class HomeView(AdminIndexView):
      @expose("/")
      @login_required
      def index(self):
          session = Session()
          DM = models.DagModel
          qry = None
  
          # restrict the dags shown if filter_by_owner and current user is not superuser
          do_filter = FILTER_BY_OWNER and (not current_user.is_superuser())
          owner_mode = conf.get('webserver', 'OWNER_MODE').strip().lower()
  
          hide_paused_dags_by_default = conf.getboolean('webserver',
                                                        'hide_paused_dags_by_default')
          show_paused_arg = request.args.get('showPaused', 'None')
          if show_paused_arg.strip().lower() == 'false':
              hide_paused = True
  
          elif show_paused_arg.strip().lower() == 'true':
              hide_paused = False
  
          else:
              hide_paused = hide_paused_dags_by_default
  
          # read orm_dags from the db
          qry = session.query(DM)
          qry_fltr = []
  
          if do_filter and owner_mode == 'ldapgroup':
              qry_fltr = qry.filter(
                  ~DM.is_subdag, DM.is_active,
                  DM.owners.in_(current_user.ldap_groups)
              ).all()
          elif do_filter and owner_mode == 'user':
              qry_fltr = qry.filter(
                  ~DM.is_subdag, DM.is_active,
                  DM.owners == current_user.user.username
              ).all()
          else:
              qry_fltr = qry.filter(
                  ~DM.is_subdag, DM.is_active
              ).all()
  
          # optionally filter out "paused" dags
          if hide_paused:
              orm_dags = {dag.dag_id: dag for dag in qry_fltr if not dag.is_paused}
  
          else:
              orm_dags = {dag.dag_id: dag for dag in qry_fltr}
  
          import_errors = session.query(models.ImportError).all()
          for ie in import_errors:
              flash(
                  "Broken DAG: [{ie.filename}] {ie.stacktrace}".format(ie=ie),
                  "error")
          session.expunge_all()
          session.commit()
          session.close()
  
          # get a list of all non-subdag dags visible to everyone
          # optionally filter out "paused" dags
          if hide_paused:
              unfiltered_webserver_dags = [dag for dag in dagbag.dags.values() if
                                           not dag.parent_dag and not dag.is_paused]
  
          else:
              unfiltered_webserver_dags = [dag for dag in dagbag.dags.values() if
                                           not dag.parent_dag]
  
          # optionally filter to get only dags that the user should see
          if do_filter and owner_mode == 'ldapgroup':
              # only show dags owned by someone in @current_user.ldap_groups
              webserver_dags = {
                  dag.dag_id: dag
                  for dag in unfiltered_webserver_dags
                  if dag.owner in current_user.ldap_groups
              }
          elif do_filter and owner_mode == 'user':
              # only show dags owned by @current_user.user.username
              webserver_dags = {
                  dag.dag_id: dag
                  for dag in unfiltered_webserver_dags
                  if dag.owner == current_user.user.username
              }
          else:
              webserver_dags = {
                  dag.dag_id: dag
                  for dag in unfiltered_webserver_dags
              }
  
          all_dag_ids = sorted(set(orm_dags.keys()) | set(webserver_dags.keys()))
          return self.render(
              'airflow/dags.html',
              webserver_dags=webserver_dags,
              orm_dags=orm_dags,
              hide_paused=hide_paused,
              all_dag_ids=all_dag_ids)
  
  
  class QueryView(wwwutils.DataProfilingMixin, BaseView):
      @expose('/')
      @wwwutils.gzipped
      def query(self):
          session = settings.Session()
          dbs = session.query(models.Connection).order_by(
              models.Connection.conn_id).all()
          session.expunge_all()
          db_choices = list(
              ((db.conn_id, db.conn_id) for db in dbs if db.get_hook()))
          conn_id_str = request.args.get('conn_id')
          csv = request.args.get('csv') == "true"
          sql = request.args.get('sql')
  
          class QueryForm(Form):
              conn_id = SelectField("Layout", choices=db_choices)
              sql = TextAreaField("SQL", widget=wwwutils.AceEditorWidget())
          data = {
              'conn_id': conn_id_str,
              'sql': sql,
          }
          results = None
          has_data = False
          error = False
          if conn_id_str:
              db = [db for db in dbs if db.conn_id == conn_id_str][0]
              hook = db.get_hook()
              try:
                  df = hook.get_pandas_df(wwwutils.limit_sql(sql, QUERY_LIMIT, conn_type=db.conn_type))
                  # df = hook.get_pandas_df(sql)
                  has_data = len(df) > 0
                  df = df.fillna('')
                  results = df.to_html(
                      classes=[
                          'table', 'table-bordered', 'table-striped', 'no-wrap'],
                      index=False,
                      na_rep='',
                  ) if has_data else ''
              except Exception as e:
                  flash(str(e), 'error')
                  error = True
  
          if has_data and len(df) == QUERY_LIMIT:
              flash(
                  "Query output truncated at " + str(QUERY_LIMIT) +
                  " rows", 'info')
  
          if not has_data and error:
              flash('No data', 'error')
  
          if csv:
              return Response(
                  response=df.to_csv(index=False),
                  status=200,
                  mimetype="application/text")
  
          form = QueryForm(request.form, data=data)
          session.commit()
          session.close()
          return self.render(
              'airflow/query.html', form=form,
              title="Ad Hoc Query",
              results=results or '',
              has_data=has_data)
  
  
  class AirflowModelView(ModelView):
      list_template = 'airflow/model_list.html'
      edit_template = 'airflow/model_edit.html'
      create_template = 'airflow/model_create.html'
      column_display_actions = True
      page_size = 500
  
  
  class ModelViewOnly(wwwutils.LoginMixin, AirflowModelView):
      """
      Modifying the base ModelView class for non edit, browse only operations
      """
      named_filter_urls = True
      can_create = False
      can_edit = False
      can_delete = False
      column_display_pk = True
  
  
  class PoolModelView(wwwutils.SuperUserMixin, AirflowModelView):
      column_list = ('pool', 'slots', 'used_slots', 'queued_slots')
      column_formatters = dict(
          pool=pool_link, used_slots=fused_slots, queued_slots=fqueued_slots)
      named_filter_urls = True
  
  
  class SlaMissModelView(wwwutils.SuperUserMixin, ModelViewOnly):
      verbose_name_plural = "SLA misses"
      verbose_name = "SLA miss"
      column_list = (
          'dag_id', 'task_id', 'execution_date', 'email_sent', 'timestamp')
      column_formatters = dict(
          task_id=task_instance_link,
          execution_date=datetime_f,
          timestamp=datetime_f,
          dag_id=dag_link)
      named_filter_urls = True
      column_searchable_list = ('dag_id', 'task_id',)
      column_filters = (
          'dag_id', 'task_id', 'email_sent', 'timestamp', 'execution_date')
      form_widget_args = {
          'email_sent': {'disabled': True},
          'timestamp': {'disabled': True},
      }
  
  
  class ChartModelView(wwwutils.DataProfilingMixin, AirflowModelView):
      verbose_name = "chart"
      verbose_name_plural = "charts"
      form_columns = (
          'label',
          'owner',
          'conn_id',
          'chart_type',
          'show_datatable',
          'x_is_date',
          'y_log_scale',
          'show_sql',
          'height',
          'sql_layout',
          'sql',
          'default_params',)
      column_list = (
          'label', 'conn_id', 'chart_type', 'owner', 'last_modified',)
      column_formatters = dict(label=label_link, last_modified=datetime_f)
      column_default_sort = ('last_modified', True)
      create_template = 'airflow/chart/create.html'
      edit_template = 'airflow/chart/edit.html'
      column_filters = ('label', 'owner.username', 'conn_id')
      column_searchable_list = ('owner.username', 'label', 'sql')
      column_descriptions = {
          'label': "Can include {{ templated_fields }} and {{ macros }}",
          'chart_type': "The type of chart to be displayed",
          'sql': "Can include {{ templated_fields }} and {{ macros }}.",
          'height': "Height of the chart, in pixels.",
          'conn_id': "Source database to run the query against",
          'x_is_date': (
              "Whether the X axis should be casted as a date field. Expect most "
              "intelligible date formats to get casted properly."
          ),
          'owner': (
              "The chart's owner, mostly used for reference and filtering in "
              "the list view."
          ),
          'show_datatable':
              "Whether to display an interactive data table under the chart.",
          'default_params': (
              'A dictionary of {"key": "values",} that define what the '
              'templated fields (parameters) values should be by default. '
              'To be valid, it needs to "eval" as a Python dict. '
              'The key values will show up in the url\'s querystring '
              'and can be altered there.'
          ),
          'show_sql': "Whether to display the SQL statement as a collapsible "
                      "section in the chart page.",
          'y_log_scale': "Whether to use a log scale for the Y axis.",
          'sql_layout': (
              "Defines the layout of the SQL that the application should "
              "expect. Depending on the tables you are sourcing from, it may "
              "make more sense to pivot / unpivot the metrics."
          ),
      }
      column_labels = {
          'sql': "SQL",
          'height': "Chart Height",
          'sql_layout': "SQL Layout",
          'show_sql': "Display the SQL Statement",
          'default_params': "Default Parameters",
      }
      form_choices = {
          'chart_type': [
              ('line', 'Line Chart'),
              ('spline', 'Spline Chart'),
              ('bar', 'Bar Chart'),
              ('column', 'Column Chart'),
              ('area', 'Overlapping Area Chart'),
              ('stacked_area', 'Stacked Area Chart'),
              ('percent_area', 'Percent Area Chart'),
              ('datatable', 'No chart, data table only'),
          ],
          'sql_layout': [
              ('series', 'SELECT series, x, y FROM ...'),
              ('columns', 'SELECT x, y (series 1), y (series 2), ... FROM ...'),
          ],
          'conn_id': [
              (c.conn_id, c.conn_id)
              for c in (
                  Session().query(models.Connection.conn_id)
                      .group_by(models.Connection.conn_id)
              )
              ]
      }
  
      def on_model_change(self, form, model, is_created=True):
          if model.iteration_no is None:
              model.iteration_no = 0
          else:
              model.iteration_no += 1
          if not model.user_id and current_user and hasattr(current_user, 'id'):
              model.user_id = current_user.id
          model.last_modified = datetime.now()
  
  chart_mapping = (
      ('line', 'lineChart'),
      ('spline', 'lineChart'),
      ('bar', 'multiBarChart'),
      ('column', 'multiBarChart'),
      ('area', 'stackedAreaChart'),
      ('stacked_area', 'stackedAreaChart'),
      ('percent_area', 'stackedAreaChart'),
      ('datatable', 'datatable'),
  )
  chart_mapping = dict(chart_mapping)
  
  
  class KnowEventView(wwwutils.DataProfilingMixin, AirflowModelView):
      verbose_name = "known event"
      verbose_name_plural = "known events"
      form_columns = (
          'label',
          'event_type',
          'start_date',
          'end_date',
          'reported_by',
          'description')
      column_list = (
          'label', 'event_type', 'start_date', 'end_date', 'reported_by')
      column_default_sort = ("start_date", True)
  
  
  class KnowEventTypeView(wwwutils.DataProfilingMixin, AirflowModelView):
      pass
  
  
  # NOTE: For debugging / troubleshooting
  # mv = KnowEventTypeView(
  #     models.KnownEventType,
  #     Session, name="Known Event Types", category="Manage")
  # admin.add_view(mv)
  # class DagPickleView(SuperUserMixin, ModelView):
  #     pass
  # mv = DagPickleView(
  #     models.DagPickle,
  #     Session, name="Pickles", category="Manage")
  # admin.add_view(mv)
  
  
  class VariableView(wwwutils.DataProfilingMixin, AirflowModelView):
      verbose_name = "Variable"
      verbose_name_plural = "Variables"
      list_template = 'airflow/variable_list.html'
  
      def hidden_field_formatter(view, context, model, name):
          if should_hide_value_for_key(model.key):
              return Markup('*' * 8)
          return getattr(model, name)
  
      form_columns = (
          'key',
          'val',
      )
      column_list = ('key', 'val', 'is_encrypted',)
      column_filters = ('key', 'val')
      column_searchable_list = ('key', 'val')
      form_widget_args = {
          'is_encrypted': {'disabled': True},
          'val': {
              'rows': 20,
          }
      }
      column_sortable_list = (
          'key',
          'val',
          'is_encrypted',
      )
      column_formatters = {
          'val': hidden_field_formatter
      }
  
      # Default flask-admin export functionality doesn't handle serialized json
      @action('varexport', 'Export', None)
      def action_varexport(self, ids):
          V = models.Variable
          session = settings.Session()
          qry = session.query(V).filter(V.id.in_(ids)).all()
          session.close()
  
          var_dict = {}
          d = json.JSONDecoder()
          for var in qry:
              val = None
              try:
                  val = d.decode(var.val)
              except:
                  val = var.val
              var_dict[var.key] = val
  
          response = make_response(json.dumps(var_dict, sort_keys=True, indent=4))
          response.headers["Content-Disposition"] = "attachment; filename=variables.json"
          return response
  
      def on_form_prefill(self, form, id):
          if should_hide_value_for_key(form.key.data):
              form.val.data = '*' * 8
  
  
  class XComView(wwwutils.SuperUserMixin, AirflowModelView):
      verbose_name = "XCom"
      verbose_name_plural = "XComs"
      page_size = 20
  
      form_columns = (
          'key',
          'value',
          'execution_date',
          'task_id',
          'dag_id',
      )
  
      form_extra_fields = {
          'value': StringField('Value'),
      }
  
      column_filters = ('key', 'timestamp', 'execution_date', 'task_id', 'dag_id')
      column_searchable_list = ('key', 'timestamp', 'execution_date', 'task_id', 'dag_id')
  
  
  class JobModelView(ModelViewOnly):
      verbose_name_plural = "jobs"
      verbose_name = "job"
      column_default_sort = ('start_date', True)
      column_filters = (
          'job_type', 'dag_id', 'state',
          'unixname', 'hostname', 'start_date', 'end_date', 'latest_heartbeat')
      column_formatters = dict(
          start_date=datetime_f,
          end_date=datetime_f,
          hostname=nobr_f,
          state=state_f,
          latest_heartbeat=datetime_f)
  
  
  class DagRunModelView(ModelViewOnly):
      verbose_name_plural = "DAG Runs"
      can_edit = True
      can_create = True
      column_editable_list = ('state',)
      verbose_name = "dag run"
      column_default_sort = ('execution_date', True)
      form_choices = {
          'state': [
              ('success', 'success'),
              ('running', 'running'),
              ('failed', 'failed'),
          ],
      }
      form_args = dict(
          dag_id=dict(validators=[validators.DataRequired()])
      )
      column_list = (
          'state', 'dag_id', 'execution_date', 'run_id', 'external_trigger')
      column_filters = column_list
      column_searchable_list = ('dag_id', 'state', 'run_id')
      column_formatters = dict(
          execution_date=datetime_f,
          state=state_f,
          start_date=datetime_f,
          dag_id=dag_link)
  
      @action('new_delete', "Delete", "Are you sure you want to delete selected records?")
      def action_new_delete(self, ids):
          session = settings.Session()
          deleted = set(session.query(models.DagRun)
              .filter(models.DagRun.id.in_(ids))
              .all())
          session.query(models.DagRun)\
              .filter(models.DagRun.id.in_(ids))\
              .delete(synchronize_session='fetch')
          session.commit()
          dirty_ids = []
          for row in deleted:
              models.DagStat.set_dirty(row.dag_id, session=session)
              dirty_ids.append(row.dag_id)
          models.DagStat.clean_dirty(dirty_ids, session=session)
          session.close()
  
      @action('set_running', "Set state to 'running'", None)
      def action_set_running(self, ids):
          self.set_dagrun_state(ids, State.RUNNING)
  
      @action('set_failed', "Set state to 'failed'", None)
      def action_set_failed(self, ids):
          self.set_dagrun_state(ids, State.FAILED)
  
      @action('set_success', "Set state to 'success'", None)
      def action_set_success(self, ids):
          self.set_dagrun_state(ids, State.SUCCESS)
  
      @provide_session
      def set_dagrun_state(self, ids, target_state, session=None):
          try:
              DR = models.DagRun
              count = 0
              dirty_ids = []
              for dr in session.query(DR).filter(DR.id.in_(ids)).all():
                  dirty_ids.append(dr.dag_id)
                  count += 1
                  dr.state = target_state
                  if target_state == State.RUNNING:
                      dr.start_date = datetime.now()
                  else:
                      dr.end_date = datetime.now()
              session.commit()
              models.DagStat.clean_dirty(dirty_ids, session=session)
              flash(
                  "{count} dag runs were set to '{target_state}'".format(**locals()))
          except Exception as ex:
              if not self.handle_view_exception(ex):
                  raise Exception("Ooops")
              flash('Failed to set state', 'error')
  
  
  class LogModelView(ModelViewOnly):
      verbose_name_plural = "logs"
      verbose_name = "log"
      column_default_sort = ('dttm', True)
      column_filters = ('dag_id', 'task_id', 'execution_date')
      column_formatters = dict(
          dttm=datetime_f, execution_date=datetime_f, dag_id=dag_link)
  
  
  class TaskInstanceModelView(ModelViewOnly):
      verbose_name_plural = "task instances"
      verbose_name = "task instance"
      column_filters = (
          'state', 'dag_id', 'task_id', 'execution_date', 'hostname',
          'queue', 'pool', 'operator', 'start_date', 'end_date')
      named_filter_urls = True
      column_formatters = dict(
          log_url=log_url_formatter,
          task_id=task_instance_link,
          hostname=nobr_f,
          state=state_f,
          execution_date=datetime_f,
          start_date=datetime_f,
          end_date=datetime_f,
          queued_dttm=datetime_f,
          dag_id=dag_link, duration=duration_f)
      column_searchable_list = ('dag_id', 'task_id', 'state')
      column_default_sort = ('start_date', True)
      form_choices = {
          'state': [
              ('success', 'success'),
              ('running', 'running'),
              ('failed', 'failed'),
          ],
      }
      column_list = (
          'state', 'dag_id', 'task_id', 'execution_date', 'operator',
          'start_date', 'end_date', 'duration', 'job_id', 'hostname',
          'unixname', 'priority_weight', 'queue', 'queued_dttm', 'try_number',
          'pool', 'log_url')
      can_delete = True
      page_size = 500
  
      @action('set_running', "Set state to 'running'", None)
      def action_set_running(self, ids):
          self.set_task_instance_state(ids, State.RUNNING)
  
      @action('set_failed', "Set state to 'failed'", None)
      def action_set_failed(self, ids):
          self.set_task_instance_state(ids, State.FAILED)
  
      @action('set_success', "Set state to 'success'", None)
      def action_set_success(self, ids):
          self.set_task_instance_state(ids, State.SUCCESS)
  
      @action('set_retry', "Set state to 'up_for_retry'", None)
      def action_set_retry(self, ids):
          self.set_task_instance_state(ids, State.UP_FOR_RETRY)
  
      @action('delete',
              lazy_gettext('Delete'),
              lazy_gettext('Are you sure you want to delete selected records?'))
      def action_delete(self, ids):
          """
          As a workaround for AIRFLOW-277, this method overrides Flask-Admin's ModelView.action_delete().
  
          TODO: this method should be removed once the below bug is fixed on Flask-Admin side.
          https://github.com/flask-admin/flask-admin/issues/1226
          """
          if 'sqlite' in conf.get('core', 'sql_alchemy_conn'):
              self.delete_task_instances(ids)
          else:
              super(TaskInstanceModelView, self).action_delete(ids)
  
      @provide_session
      def set_task_instance_state(self, ids, target_state, session=None):
          try:
              TI = models.TaskInstance
              count = len(ids)
              for id in ids:
                  task_id, dag_id, execution_date = id.split(',')
                  execution_date = datetime.strptime(execution_date, '%Y-%m-%d %H:%M:%S')
                  ti = session.query(TI).filter(TI.task_id == task_id,
                                                TI.dag_id == dag_id,
                                                TI.execution_date == execution_date).one()
                  ti.state = target_state
              session.commit()
              flash(
                  "{count} task instances were set to '{target_state}'".format(**locals()))
          except Exception as ex:
              if not self.handle_view_exception(ex):
                  raise Exception("Ooops")
              flash('Failed to set state', 'error')
  
      @provide_session
      def delete_task_instances(self, ids, session=None):
          try:
              TI = models.TaskInstance
              count = 0
              for id in ids:
                  task_id, dag_id, execution_date = id.split(',')
                  execution_date = datetime.strptime(execution_date, '%Y-%m-%d %H:%M:%S')
                  count += session.query(TI).filter(TI.task_id == task_id,
                                                    TI.dag_id == dag_id,
                                                    TI.execution_date == execution_date).delete()
              session.commit()
              flash("{count} task instances were deleted".format(**locals()))
          except Exception as ex:
              if not self.handle_view_exception(ex):
                  raise Exception("Ooops")
              flash('Failed to delete', 'error')
  
      def get_one(self, id):
          """
          As a workaround for AIRFLOW-252, this method overrides Flask-Admin's ModelView.get_one().
  
          TODO: this method should be removed once the below bug is fixed on Flask-Admin side.
          https://github.com/flask-admin/flask-admin/issues/1226
          """
          task_id, dag_id, execution_date = iterdecode(id)
          execution_date = dateutil.parser.parse(execution_date)
          return self.session.query(self.model).get((task_id, dag_id, execution_date))
  
  
  class ConnectionModelView(wwwutils.SuperUserMixin, AirflowModelView):
      create_template = 'airflow/conn_create.html'
      edit_template = 'airflow/conn_edit.html'
      list_template = 'airflow/conn_list.html'
      form_columns = (
          'conn_id',
          'conn_type',
          'host',
          'schema',
          'login',
          'password',
          'port',
          'extra',
          'extra__jdbc__drv_path',
          'extra__jdbc__drv_clsname',
          'extra__google_cloud_platform__project',
          'extra__google_cloud_platform__key_path',
          'extra__google_cloud_platform__scope',
      )
      verbose_name = "Connection"
      verbose_name_plural = "Connections"
      column_default_sort = ('conn_id', False)
      column_list = ('conn_id', 'conn_type', 'host', 'port', 'is_encrypted', 'is_extra_encrypted',)
      form_overrides = dict(_password=PasswordField)
      form_widget_args = {
          'is_extra_encrypted': {'disabled': True},
          'is_encrypted': {'disabled': True},
      }
      # Used to customized the form, the forms elements get rendered
      # and results are stored in the extra field as json. All of these
      # need to be prefixed with extra__ and then the conn_type ___ as in
      # extra__{conn_type}__name. You can also hide form elements and rename
      # others from the connection_form.js file
      form_extra_fields = {
          'extra__jdbc__drv_path': StringField('Driver Path'),
          'extra__jdbc__drv_clsname': StringField('Driver Class'),
          'extra__google_cloud_platform__project': StringField('Project Id'),
          'extra__google_cloud_platform__key_path': StringField('Keyfile Path'),
          'extra__google_cloud_platform__scope': StringField('Scopes (comma seperated)'),
  
      }
      form_choices = {
          'conn_type': models.Connection._types
      }
  
      def on_model_change(self, form, model, is_created):
          formdata = form.data
          if formdata['conn_type'] in ['jdbc', 'google_cloud_platform']:
              extra = {
                  key:formdata[key]
                  for key in self.form_extra_fields.keys() if key in formdata}
              model.extra = json.dumps(extra)
  
      @classmethod
      def alert_fernet_key(cls):
          fk = None
          try:
              fk = conf.get('core', 'fernet_key')
          except:
              pass
          return fk is None
  
      @classmethod
      def is_secure(cls):
          """
          Used to display a message in the Connection list view making it clear
          that the passwords and `extra` field can't be encrypted.
          """
          is_secure = False
          try:
              import cryptography
              conf.get('core', 'fernet_key')
              is_secure = True
          except:
              pass
          return is_secure
  
      def on_form_prefill(self, form, id):
          try:
              d = json.loads(form.data.get('extra', '{}'))
          except Exception as e:
              d = {}
  
          for field in list(self.form_extra_fields.keys()):
              value = d.get(field, '')
              if value:
                  field = getattr(form, field)
                  field.data = value
  
  
  class UserModelView(wwwutils.SuperUserMixin, AirflowModelView):
      verbose_name = "User"
      verbose_name_plural = "Users"
      column_default_sort = 'username'
  
  
  class VersionView(wwwutils.SuperUserMixin, LoggingMixin, BaseView):
      @expose('/')
      def version(self):
          # Look at the version from setup.py
          try:
              airflow_version = pkg_resources.require("airflow")[0].version
          except Exception as e:
              airflow_version = None
              self.logger.error(e)
  
          # Get the Git repo and git hash
          git_version = None
          try:
              with open(os.path.join(*[settings.AIRFLOW_HOME, 'airflow', 'git_version'])) as f:
                  git_version = f.readline()
          except Exception as e:
              self.logger.error(e)
  
          # Render information
          title = "Version Info"
          return self.render('airflow/version.html',
                             title=title,
                             airflow_version=airflow_version,
                             git_version=git_version)
  
  
  class ConfigurationView(wwwutils.SuperUserMixin, BaseView):
      @expose('/')
      def conf(self):
          raw = request.args.get('raw') == "true"
          title = "Airflow Configuration"
          subtitle = conf.AIRFLOW_CONFIG
          if conf.getboolean("webserver", "expose_config"):
              with open(conf.AIRFLOW_CONFIG, 'r') as f:
                  config = f.read()
              table = [(section, key, value, source)
                       for section, parameters in conf.as_dict(True, True).items()
                       for key, (value, source) in parameters.items()]
  
          else:
              config = (
                  "# You Airflow administrator chose not to expose the "
                  "configuration, most likely for security reasons.")
              table = None
          if raw:
              return Response(
                  response=config,
                  status=200,
                  mimetype="application/text")
          else:
              code_html = Markup(highlight(
                  config,
                  lexers.IniLexer(),  # Lexer call
                  HtmlFormatter(noclasses=True))
              )
              return self.render(
                  'airflow/config.html',
                  pre_subtitle=settings.HEADER + "  v" + airflow.__version__,
                  code_html=code_html, title=title, subtitle=subtitle,
                  table=table)
  
  
  class DagModelView(wwwutils.SuperUserMixin, ModelView):
      column_list = ('dag_id', 'owners')
      column_editable_list = ('is_paused',)
      form_excluded_columns = ('is_subdag', 'is_active')
      column_searchable_list = ('dag_id',)
      column_filters = (
          'dag_id', 'owners', 'is_paused', 'is_active', 'is_subdag',
          'last_scheduler_run', 'last_expired')
      form_widget_args = {
          'last_scheduler_run': {'disabled': True},
          'fileloc': {'disabled': True},
          'is_paused': {'disabled': True},
          'last_pickled': {'disabled': True},
          'pickle_id': {'disabled': True},
          'last_loaded': {'disabled': True},
          'last_expired': {'disabled': True},
          'pickle_size': {'disabled': True},
          'scheduler_lock': {'disabled': True},
          'owners': {'disabled': True},
      }
      column_formatters = dict(
          dag_id=dag_link,
      )
      can_delete = False
      can_create = False
      page_size = 50
      list_template = 'airflow/list_dags.html'
      named_filter_urls = True
  
      def get_query(self):
          """
          Default filters for model
          """
          return (
              super(DagModelView, self)
                  .get_query()
                  .filter(or_(models.DagModel.is_active, models.DagModel.is_paused))
                  .filter(~models.DagModel.is_subdag)
          )
  
      def get_count_query(self):
          """
          Default filters for model
          """
          return (
              super(DagModelView, self)
                  .get_count_query()
                  .filter(models.DagModel.is_active)
                  .filter(~models.DagModel.is_subdag)
          )
  