You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: prometheus_test.go
    path of file: ./repos/grafana/pkg/tests/api/prometheus
    
    the code of the file until where you have to start completion: package prometheus

import (
	"bytes"
	"context"
	"encoding/json"
	"fmt"
	"net/http"
	"net/http/httptest"
	"testing"

	"github.com/stretchr/testify/require"

	"github.com/grafana/grafana/pkg/api/dtos"
	"github.com/grafana/grafana/pkg/components/simplejson"
	"github.com/grafana/grafana/pkg/services/datasources"
	"github.com/grafana/grafana/pkg/services/org"
	"github.com/grafana/grafana/pkg/services/user"
	"github.com/grafana/grafana/pkg/tests/testinfra"
	"github.com/grafana/grafana/pkg/tests/testsuite"
)

func TestMain(m *testing.M) {
	testsuite.Run(m)
}

func TestIntegrationPrometheus(t *testing.T) {
	if testing.Short() {
		t.Skip("skipping integration test")
	}
	dir, path := testinfra.CreateGrafDir(t, testinfra.GrafanaOpts{
		DisableAnonymous: true,
	})

	grafanaListeningAddr, testEnv := testinfra.StartGrafanaEnv(t, dir, path)
	ctx := context.Background()

	u := testinfra.CreateUser(t, testEnv.SQLStore, user.CreateUserCommand{
		DefaultOrgRole: string(org.RoleAdmin),
		Password:       "admin",
		Login:          "admin",
	})

	var outgoingRequest *http.Request
	outgoingServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		outgoingRequest = r
		w.WriteHeader(http.StatusUnauthorized)
	}))
	t.Cleanup(outgoingServer.Close)

	jsonData := simplejson.NewFromAny(map[string]any{
		"httpMethod":            "post",
		"httpHeaderName1":       "X-CUSTOM-HEADER",
		"customQueryParameters": "q1=1&q2=2",
	})
	secureJSONData := map[string]string{
		"basicAuthPassword": "basicAuthPassword",
		"httpHeaderValue1":  "custom-header-value",
	}

	uid := "prometheus"
	_, err := testEnv.Server.HTTPServer.DataSourcesService.AddDataSource(ctx, &datasources.AddDataSourceCommand{
		OrgID:          u.OrgID,
		Access:         datasources.DS_ACCESS_PROXY,
		Name:           "Prometheus",
		Type:           datasources.DS_PROMETHEUS,
		UID:            uid,
		URL:            outgoingServer.URL,
		BasicAuth:      true,
		BasicAuthUser:  "basicAuthUser",
		JsonData:       jsonData,
		SecureJsonData: secureJSONData,
	})
	require.NoError(t, err)

	t.Run("When calling /api/ds/query should set expected headers on outgoing HTTP request", func(t *testing.T) {
		query := simplejson.NewFromAny(map[string]any{
			"datasource": map[string]any{
				"uid": uid,
			},
			"expr":         "1",
			"instantQuery": true,
		})
		buf1 := &bytes.Buffer{}
		err = json.NewEncoder(buf1).Encode(dtos.MetricRequest{
			From:    "1668078080000",
			To:      "1668081680000",
			Queries: []*simplejson.Json{query},
		})
		require.NoError(t, err)
		u := fmt.Sprintf("http://admin:admin@%s/api/ds/query", grafanaListeningAddr)
		// nolint:gosec
		resp, err := http.Post(u, "application/json", buf1)
		require.NoError(t, err)
		t.Cleanup(func() {
			_ = 
    
func TestIntegrationPrometheus(t *testing.T) {
	if testing.Short() {
		t.Skip("skipping integration test")
	}
	dir, path := testinfra.CreateGrafDir(t, testinfra.GrafanaOpts{
		DisableAnonymous: true,
	})

	grafanaListeningAddr, testEnv := testinfra.StartGrafanaEnv(t, dir, path)
	ctx := context.Background()

	u := testinfra.CreateUser(t, testEnv.SQLStore, user.CreateUserCommand{
		DefaultOrgRole: string(org.RoleAdmin),
		Password:       "admin",
		Login:          "admin",
	})

	var outgoingRequest *http.Request
	outgoingServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		outgoingRequest = r
		w.WriteHeader(http.StatusUnauthorized)
	}))
	t.Cleanup(outgoingServer.Close)

	jsonData := simplejson.NewFromAny(map[string]any{
		"httpMethod":            "post",
		"httpHeaderName1":       "X-CUSTOM-HEADER",
		"customQueryParameters": "q1=1&q2=2",
	})
	secureJSONData := map[string]string{
		"basicAuthPassword": "basicAuthPassword",
		"httpHeaderValue1":  "custom-header-value",
	}

	uid := "prometheus"
	_, err := testEnv.Server.HTTPServer.DataSourcesService.AddDataSource(ctx, &datasources.AddDataSourceCommand{
		OrgID:          u.OrgID,
		Access:         datasources.DS_ACCESS_PROXY,
		Name:           "Prometheus",
		Type:           datasources.DS_PROMETHEUS,
		UID:            uid,
		URL:            outgoingServer.URL,
		BasicAuth:      true,
		BasicAuthUser:  "basicAuthUser",
		JsonData:       jsonData,
		SecureJsonData: secureJSONData,
	})
	require.NoError(t, err)

	t.Run("When calling /api/ds/query should set expected headers on outgoing HTTP request", func(t *testing.T) {
		query := simplejson.NewFromAny(map[string]any{
			"datasource": map[string]any{
				"uid": uid,
			},
			"expr":         "1",
			"instantQuery": true,
		})
		buf1 := &bytes.Buffer{}
		err = json.NewEncoder(buf1).Encode(dtos.MetricRequest{
			From:    "1668078080000",
			To:      "1668081680000",
			Queries: []*simplejson.Json{query},
		})
		require.NoError(t, err)
		u := fmt.Sprintf("http://admin:admin@%s/api/ds/query", grafanaListeningAddr)
		// nolint:gosec
		resp, err := http.Post(u, "application/json", buf1)
		require.NoError(t, err)
		t.Cleanup(func() {
			_ = resp.Body.Close()
		})

		require.NotNil(t, outgoingRequest)
		require.Equal(t, "/api/v1/query_range?q1=1&q2=2", outgoingRequest.URL.String())
		require.Equal(t, "custom-header-value", outgoingRequest.Header.Get("X-CUSTOM-HEADER"))
		username, pwd, ok := outgoingRequest.BasicAuth()
		require.True(t, ok)
		require.Equal(t, "basicAuthUser", username)
		require.Equal(t, "basicAuthPassword", pwd)
	})

	t.Run("When calling /api/ds/query should set expected headers on outgoing HTTP request", func(t *testing.T) {
		query := simplejson.NewFromAny(map[string]any{
			"datasource": map[string]any{
				"uid": uid,
			},
			"expr":         "up",
			"instantQuery": true,
		})
		buf1 := &bytes.Buffer{}
		err = json.NewEncoder(buf1).Encode(dtos.MetricRequest{
			From:    "now-1h",
			To:      "now",
			Queries: []*simplejson.Json{query},
		})
		require.NoError(t, err)
		u := fmt.Sprintf("http://admin:admin@%s/api/ds/query", grafanaListeningAddr)
		// nolint:gosec
		resp, err := http.Post(u, "application/json", buf1)
		require.NoError(t, err)
		t.Cleanup(func() {
			_ = resp.Body.Close()
		})

		require.NotNil(t, outgoingRequest)
		require.Equal(t, "/api/v1/query_range", outgoingRequest.URL.Path)
		require.Contains(t, outgoingRequest.URL.String(), "?q1=1&q2=2")
		require.Equal(t, "custom-header-value", outgoingRequest.Header.Get("X-CUSTOM-HEADER"))
		username, pwd, ok := outgoingRequest.BasicAuth()
		require.True(t, ok)
		require.Equal(t, "basicAuthUser", username)
		require.Equal(t, "basicAuthPassword", pwd)
	})
}