slack@obindo.com

Written by Alex

Post the contents of a message, and any attached files, to a Slack channel.

/**************************
Documentation Links/Description:
OAuth2 Docs: https://api.slack.com/docs/oauth
API Ref Root: https://api.slack.com/
Message Post: https://api.slack.com/methods/chat.postMessage
**************************/

var oauth2Credentials = {};

//#region PRIVATE set my oauth2 credentials

var requestUrl = 'https://slack.com/oauth/authorize?';
var scopes = 'post client';
var apiRoot = 'https://slack.com/api/';
var maxLength = 5000;

oauth2.getAuthRedirectUrl = function () {
  var args = {
    scope: scopes,
    state: tokens.getId(),
    client_id: oauth2Credentials.clientID,
    redirect_uri: oauth2.getCallbackUrl(true)
  };

return requestUrl + util.getQueryArgsFromObject(args);
}

oauth2.onAuthResponse = function (q) {
  var qArgs = util.getObjectFromQueryArgs(q);

var args = {
    client_id: oauth2Credentials.clientID,
    client_secret: oauth2Credentials.clientSecret,
    redirect_uri: oauth2.getCallbackUrl(true),
    code: qArgs.code
  };

var response = post({ url: apiRoot + 'oauth.access', args: args });

tokens.loadFromId(qArgs.state);
  tokens.accessToken = util.jsonify(response.text);
}

function getMessageText() {
  if (validText(message.strippedText)) return message.strippedText;
  if (validText(message.text)) return message.text;
  if (validText(message.subject)) return message.subject;
  return " ";

function validText(s) { return (s && s.length > 0); }
}

function getUsername(token) {
  var body = {
    token: token,
    pretty: 1
  };
  var response = get({ url: apiRoot + 'auth.test?' + util.getQueryArgsFromObject(body) });

return util.jsonify(response.text).user;
}

function getUserId(token) {
  var body = { token: token, pretty: 1 };
  var response = get({ url: apiRoot + 'auth.test?' + util.getQueryArgsFromObject(body) });

return util.jsonify(response.text).user_id;
}

// Conversation names can only contain lowercase letters, numbers, hyphens, and underscores, and must be 80 characters or less.
function formatChannel(channel) {
  var formattedChannel = (channel[0] == '#' ? channel.substring(1) : channel)
    .replace(/\s/g, "-")
    .toLowerCase()
    .match("[a-z0-9_-]*")[0]
    .substring(0, 80);

return formattedChannel;
}

function truncateText(s) {
  if (s.length <= maxLength) return s;

var i = s.lastIndexOf(' ', maxLength);
  return ((i > 0) ? s.substring(0, i) : s.substring(0, maxLength)) + '...';
}

function sendErrorEmail(channel, error) {
  var text = '';
  var subject = '';

if (error == 'no_subject') {
    subject = "I need a channel";
    text = "I'm sorry, but I couldn't figure out into what channel you would like to post that. " +
      "Please try again with the channel in the email subject.";
  } else if (error == 'channel_not_found') {
    subject = "I couldn't find that";
    text = "I'm sorry, but I couldn't find a channel named " + channel + " in your Slack account. " +
      "Please sign into Slack, create that channel, and then try again.";
  } else {
    subject = "Something happened";
    text = "I'm sorry, that didn't work for some reason (" + error + "). " +
      "Please try again.";
  }

sendEmail(message.from.emailAddress, subject, text);
}

function uploadFile(file, channel, token) {
  var body = {
    token: token,
    channels: channel,
    file: file,
    filetype: file.contentType,
    filename: file.name
  };

var response = post({ url: apiRoot + 'files.upload', args: body });
  var j = util.jsonify(response.text);

if (j.error)
    sendErrorEmail(channel, j.error);
}

function isErrorResponse(response) {
  return response.error;
}

function isChannelNotFoundError(response) {
  return isErrorResponse(response) && response.error == "channel_not_found";
}

function postMessage(text, channel, token) {
  try {
    var blocks = [
      {
        "type": "section",
        "text": {
          "type": "mrkdwn",
          "text": text
        }
      }
    ];

var blocksJson = "[";
    for (var i = 0; i < blocks.length; i++) {
      blocksJson += util.stringify(blocks[i]);

if (i != blocks.length - 1) {
        blocksJson += ","
      } else {
        blocksJson += "]"
      };
    }

var body = {
      "channel": channel,
      "blocks": blocksJson,
      "username": "Obindo",
      "icon_url": "http://connect.obindo.com/images/slacktopus%20110.png",
      "pretty": 1
    }

var response = post({
      url: apiRoot + 'chat.postMessage',
      args: body,
      header: {
        "Authorization": "Bearer " + token
      }
    });

return util.jsonify(response.text);
  } catch (ex) {
    reply("Slack Script Error", "Sorry, somehing went very wrong with the Slack integration script.");
  }
}

function createChannel(channel, token) {
  var response = post({
    url: apiRoot + "conversations.create?name=" + channel,
    header: {
      "Authorization": "Bearer " + token
    }
  })

return util.jsonify(response.text);
}

if (isErrorResponse(slackMessageResp)) {
      reply("Slack Error", "Sorry, we could not post the requested message to channel #" + channel + " due to the following slack error: " + slackMessageResp.error + ".");
    }
  }
}

function main(message) {
  var channel = formatChannel(message.subject);

if (channel == "") {
    sendErrorEmail('', 'no_subject');
    return;
  }

var token = tokens.accessToken.access_token;

if (message.text) {
    var text = truncateText(getMessageText());
    postMessageWithChannelCreation(text, channel, token);
  }

if (message.files && message.files.length > 0) {
    for (var i = 0; i < message.files.length; i++) {
      uploadFile(message.files[i], channel, token);
    }
  }
}

$(function () {
  main(message);
});