aws lambda function to process github hook from sns, add user to team, and notify by slack.

processGitHubHook.js

var aws = require('aws-sdk');
var kms = new aws.KMS({ region: 'us-east-1' });
var lambda = new aws.Lambda({region: 'ap-northeast-1'});

var encrypted_token = 'CiD0R0tv46w7LNpO0GlZpLfZk2O0Oy66IF83rG6olDY7yBKwAQEBAgB49EdL\nb+OsOyzaTtBpWaS32ZNjtDsuuiBfN6xuqJQ2O8gAAACHMIGEBgkqhkiG9w0B\nBwagdzB1AgEAMHAGCSqGSIb3DQEHATAeBglghkgBZQMEAS4wEQQMsDOYHRzB\nN/5q/XCTAgEQgEOnHbGFykvpf06OQ1uQG9P5VjooLu8oSynMp9Cqt5SvaPUC\nKpHkPnnew8nKYhDIcxyLYd/A3vYsHZGWZ3FwN7kx0tIx\n';
var team_id = 1234567;
var valid_comment = 'join';

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

    var comment = message.comment.body;
    var user = message.comment.user.login;
    var icon = message.comment.user.avatar_url;
    console.log('user: ' + user);
    console.log('comment: ' + comment);
            
    var p = {CiphertextBlob: new Buffer(encrypted_token, 'base64')};
    kms.decrypt(p, function(err, data) {
        if (err) context.fail(err);
        else {
            var github_token = data.Plaintext.toString();
            //console.log('token: ' + github_token);
            
            var http = require('https');
            var options = {
                host: 'api.github.com',
                port: 443,
                path: '/teams/' + team_id + '/memberships/' + user,
                headers: {'Authorization': 'token ' + github_token, 'User-Agent': 'ijin'},
                method: 'PUT'
            };

            callback = function(response) {
                var rsp = '';
                var msg = '';
                var status = response.statusCode;
                console.log('status code: ' + status);

                response.on('data', function (chunk) { rsp += chunk; });
                
                response.on('end', function () {
                    console.log('response: ' + rsp);
                    if (status == 200){
                        msg = 'Added to the team';
                        console.log(msg);
                        var payload = { username: user, icon_url: icon, text: msg }
                        lambda.invoke({FunctionName: 'slack', Payload: JSON.stringify(payload)}, function(err, data) {
                            if (err) console.log(err, err.stack);
                            else context.succeed(msg);
                        });
                    } else {
                        msg = 'Failed to add user to the team';
                        console.log(msg);
                        context.fail(msg);
                    }
                });
            }

            if (valid_comment.indexOf(comment) < 0) context.fail('invalid comment');
            else {
                var req = http.request(options, callback);
                req.end();
            }
        }
    });

};