docs: function addMedia(uri, contentType, safe) {
    if (!uri || uri === '') {
      return 'You must enter a valid uri'
    }
    safe = safe || 0
    return new Promise((resolve, reject) => {
  
      var config = require('../config/config.js')
      var conn = wc_db.getConnection(config.db)
  
      // sniff content type
      if (!contentType) {
        // image
        if (uri.indexOf('.jpg') !== -1) {
          contentType = 'image'
        }
        if (uri.indexOf('.png') !== -1) {
          contentType = 'image'
        }
        if (uri.indexOf('.gif') !== -1) {
          contentType = 'image'
        }
        if (uri.indexOf('.svg') !== -1) {
          contentType = 'image'
        }
        // video
        if (uri.indexOf('.mp4') !== -1) {
          contentType = 'video'
        }
        if (uri.indexOf('.mpg') !== -1) {
          contentType = 'video'
        }
        if (uri.indexOf('.mov') !== -1) {
          contentType = 'video'
        }
        if (uri.indexOf('.wmv') !== -1) {
          contentType = 'video'
        }
        if (uri.indexOf('.avi') !== -1) {
          contentType = 'video'
        }
        if (uri.indexOf('.m4v') !== -1) {
          contentType = 'video'
        }
        if (uri.indexOf('.mkv') !== -1) {
          contentType = 'video'
        }
        // audio
        if (uri.indexOf('.mp3') !== -1) {
          contentType = 'audio'
        }
        if (uri.indexOf('.ogg') !== -1) {
          contentType = 'video'
        }
        if (uri.indexOf('.flv') !== -1) {
          contentType = 'video'
        }
      }
  
      var sql = 'INSERT into Media values (NULL, :uri, NULL, NULL, NULL, :contentType, ' + safe + ')'
  
      conn.query(sql, { replacements: { "uri" : uri, "contentType" : contentType } }).then(function(ret){
        return resolve({"ret" : ret, "conn" : conn})
      }).catch(function(err) {
        return reject(err)
      })
  
    })
  
  }