Posts an Amazon Autoscaling SNS message to a slack webhook

sns2slack.js

var https = require('https');
var util = require('util');
var webhook = '/services/T00000000/B00000000/XXXXXXXXXXXXXXXXXXXXXXXX';

exports.handler = function(event, context) {
    console.log(JSON.stringify(event, null, 2));
    console.log('From SNS:', event.Records[0].Sns.Message);

    var postData = {
        "text": "*" + event.Records[0].Sns.Subject + "*"
    };

    var message = event.Records[0].Sns.Message;

    postData.attachments = [{
         "text": message
    }];

    try {
        message = JSON.parse(message);
        postData.attachments[0].text = message.Description;
        postData.attachments[0]["fields"] = [];
        for (var key of ['AutoScalingGroupName', 'Cause', 'Event', 'EC2InstanceId', 'Progress', 'StartTime']) {
            var field = {
                title: key,
                value: message[key],
                short: false
            };
            postData.attachments[0]["fields"].push(field);
        }
    } catch (err) {
        console.log("Message body was not a JSON payload");
    }
    
    var options = {
        method: 'POST',
        hostname: 'hooks.slack.com',
        port: 443,
        path: webhook
    };

    var req = https.request(options, function(res) {
      res.setEncoding('utf8');
      res.on('data', function (chunk) {
        context.done(null);
      });
    });
    
    req.on('error', function(e) {
      console.log('problem with request: ' + e.message);
    });    

    req.write(util.format("%j", postData));
    req.end();
};