 #   HUBOT_GRAFANA_S3_SECRET_ACCESS_KEY - Optional; Secret access key for S3
 #   HUBOT_GRAFANA_S3_PREFIX - Optional; Bucket prefix (useful for shared buckets)
 #   HUBOT_GRAFANA_S3_REGION - Optional; Bucket region (defaults to us-standard)
+#   HUBOT_SLACK_URL - Optional; You should use this if you are using slack adapter and you don't own an S3 account.
 #
 # Dependencies:
 #   "knox": "^0.9.2"

    "#{prefix}/#{crypto.randomBytes(20).toString('hex')}.png"

  # Fetch an image from provided URL, upload it to S3, returning the resulting URL
  fetchAndUpload = (msg, title, url, link) ->
    if grafana_api_key
        requestHeaders =
          encoding: null,

  s3_style = process.env.HUBOT_GRAFANA_S3_STYLE if process.env.HUBOT_GRAFANA_S3_STYLE
  s3_region = process.env.HUBOT_GRAFANA_S3_REGION or 'us-standard'
  s3_port = process.env.HUBOT_GRAFANA_S3_PORT if process.env.HUBOT_GRAFANA_S3_PORT
  slack_url = process.env.HUBOT_SLACK_URL
  site = 's3' if (s3_bucket && s3_access_key && s3_secret_key) else if (slack_url && robot.adapterName == 'slack') else ''
  isUploadSupported = site != ''

  # Get a specific dashboard with options
  robot.respond /(?:grafana|graph|graf) (?:dash|dashboard|db) ([A-Za-z0-9\-\:_]+)(.*)?/i, (msg) ->
