How can I access 'Location' from HTTP response in Coffee script?

Question

I'm trying to integrate Jenkins with Slack, using Hubot. I've found jenkins.coffee script in Hubot scripts and it works fine for what I was planning on doing. Now, I would like to get the Build number of a triggered job after I run a command to build it from Slack. In order to do that, I would like to get the 'Location' from http response.

This is the function that builds a job when I say @Hubot jenkins build <job name>

jenkinsBuild = (msg, buildWithEmptyParameters) ->
    url = process.env.HUBOT_JENKINS_URL
    job = querystring.escape msg.match[1]
    params = msg.match[3]
    command = if buildWithEmptyParameters then "buildWithParameters" else "build"
    path = if params then "#{url}/job/#{job}/buildWithParameters?#{params}" else "#{url}/job/#{job}/#{command}"

    req = msg.http(path)

    if process.env.HUBOT_JENKINS_AUTH
      auth = new Buffer(process.env.HUBOT_JENKINS_AUTH).toString('base64')
      req.headers Authorization: "Basic #{auth}"

    req.header('Content-Length', 0)
    req.post() (err, res, body) ->
        if err
          msg.reply "Jenkins says: #{err}"
        else if 200 <= res.statusCode < 400 # Or, not an error code.
          msg.reply "(#{res.statusCode}) Build started for #{job} #{url}/job/#{job}"
        else if 400 == res.statusCode
          jenkinsBuild(msg, true)
        else if 404 == res.statusCode
          msg.reply "Build not found, double check that it exists and is spelt correctly."
        else
          msg.reply "Jenkins says: Status #{res.statusCode} #{body}"

What exactly should I write in msg.reply to get the Location?

TIA :)

Answer 1

I finally did it with res.headers["location"]