process a stash webhook and post to slack

stash-webhook-to-slack.js

var issues;

exports.post = function(request, response) {
    var rep = request.body.repository;
    var ref = request.body.refChanges;
    var ch = request.body.changesets;

    // let me specify the destination and noise level via the query string
    var channel = "#devops";
    if (request.query.channel != undefined && request.query.channel != null)
        channel = request.query.channel;
    var alert = false;
    if (request.query.alert != undefined && request.query.alert != null)
        alert = true;

    var Slack = require('slack-node');
    var slack = new Slack("[mywebhookskey]", "[myteamname]");

    var stash = {
        root: "https://mystashurl.com",
        key: rep.project.key,
        slug: rep.slug,
        name: rep.name
    };

    for (var y = 0; y < ref.length; y++) {
        issues = "";
        var r = {
            type: ref[y].type,
            from: ref[y].fromHash,
            to: ref[y].toHash,
            branch: ref[y].refId.replace("refs/heads/", "").replace("refs/tags/", ""),
            branchFull: ref[y].refId
        }
        var slackMsg = alert ? (channel.indexOf("#") < 0 ? "<!group> " : "<!everyone> ") : "";

        if (r.type === "UPDATE") {
            slackMsg += "Commit on *" + stash.name + "* to branch" + " *<" + stash.root + "/projects/" + stash.key + "/repos/" + stash.slug + "/commits/" + r.branchFull + "|" + r.branch + ">*";
        } else if (r.type == "DELETE") {
            slackMsg += "Deleted remote branch *" + r.branch + "* on *<" + stash.root + "/projects/" + stash.key + "/repos/" + stash.slug + "/branches|" + stash.name + ">*";
        } else if (r.type == "ADD") {
            var bn = "branch";
            if (r.branchFull.indexOf("/tags/") > -1) {
                bn = "tag";
            }
            slackMsg += "Created remote " + bn + " *<" + stash.root + "/projects/" + stash.key + "/repos/" + stash.slug + "/browse/?at=" + r.branchFull + "|" + r.branch + ">* on *" + stash.name + "*";
        }

        var started = false;
        var anyCommits = false;
        var commitAttachments = [];
        for (var x = ch.values.length; x > 0; x--) {
            var v = ch.values[x - 1];
            var c = {
                to: v.toCommit == null ? "" : v.toCommit.id,
                toDisplay: v.toCommit == null ? "" : v.toCommit.displayId,
                from: v.fromCommit == null ? "" : v.fromCommit.id,
                author: v.toCommit == null ? "" : v.toCommit.author,
                message: v.toCommit == null ? "" : v.toCommit.message,
                mods: v.changes.values.filter(function(e) {
                    return e.type === "MODIFY";
                }).length,
                adds: v.changes.values.filter(function(e) {
                    return e.type === "ADD";
                }).length,
                parents: v.toCommit.parents.length
            };

            if (r.type === "ADD") {
                if (c.from === r.from) {
                    started = true;
                }

                if (started) {
                    commitAttachments.push(buildAttachment(stash, c));
                    anyCommits = true;
                }

                if (c.to === r.to) {
                    if (!anyCommits && c.parents <= 1) {
                        commitAttachments.push(buildAttachment(stash, c));
                    }
                    started = false;
                }
            } else {
                commitAttachments.push(buildAttachment(stash, c));
            }
        }
        
        var attach = r.type === "ADD" ? commitAttachments : commitAttachments.reverse();
        var trimAttach = attach.slice(0, 3); // there could be 100 commits, lets not post all of that to chat
        var more = attach.length - trimAttach.length;
        if (more > 0) {
            var moreMessage = "_" + more + " more commit(s)_";
            trimAttach.push({
                "fallback": moreMessage,
                "pretext": moreMessage,
                "mrkdwn_in": ["pretext", "fallback"]
            })
        }

        slack.webhook({
            text: slackMsg,
            channel: channel,
            attachments: trimAttach
        }, function(err, response) {
                console.log(response);
            });
    }
    response.send(statusCodes.OK, { message: 'Message Sent' });
};

function buildAttachment(stash, c) {
    var almPattern = /[A-Za-z]+\-[0-9]+/g;
    var msgFull = c.message.replace(almPattern, buildAlmLink);
    // get rid of the line breaks and trim up the message just enough to get the point
    var msg = msgFull.replace(/\\n/g, " ").replace(/\n/g, " ").replace(/\\/g, " ").substr(0, 100)

    var m = "_" + c.author.name + "_ - " + msg;
    m += (c.message.length > 100) ? "..." : "";
    m = m.trim();
    m += " (<" + stash.root + "/projects/" + stash.key + "/repos/" + stash.slug + "/commits/" + c.to + "|" + c.toDisplay + ">)\n";

    var a = {
        "fallback": m,
        "pretext": m,
        "color": "#003366",
        "fields": [
            {
                "title": "Changes",
                "value": "*" + c.mods + "* modified, *" + c.adds + "* added",
                "short": true
            }
        ],
        "mrkdwn_in": ["pretext", "fallback", "fields"]
    };

    if (issues.length > 0) {
        a.fields.push({
            "title": "JIRA Issues",
            "value": issues,
            "short": true
        });
        a.fields.reverse();
        issues = "";
    }
    return a;
}

function buildAlmLink(match, p1, p2, p3, offset, string) {
    // p1 is nondigits, p2 digits, and p3 non-alphanumerics
    var link = " <https://myjiraurl.com/browse/" + match.toUpperCase() + "|" + match.toUpperCase() + ">";
    issues += link;
    return "";
}