Wednesday, 11 May 2016

JavaScript TDD: getting Mocha tests running on Bamboo

G'day:
We've finally having a chance to move forward with our JavaScript TDD / testing. You might have recalled that I'd lamented in the past we'd wanted to take this sort of thing more seriously with our JS, but it was taking an age to get it moving. Well now it's been placed in the hands of the devs, so it's... moving.

This came to us on Friday, and we had a wee faff around with it then, but didn't make a huge amount of progress. On the weekend I decided to get a proof of concept working, which I did on Saturday. It was kind of a bit of a mission, and I didn't write down what I did so I replicated it again on my other laptop this morning, and took some notes. Which I'll now pad out into an article.

We'd been looking at Jasmine for our JavaScript TDD, but this was based solely on that being the one JS testing framework I was aware of. Jasmine works really well, and superficially I like the approach it has (I say "superficially" cos that's the full extent of my exposure to it). However when I went to see how to get Bamboo running Jasmine tests, all I could really find was chatter about Mocha. I had a quick look at Mocha and it seemed much the same as Jasmine, and looked pretty good, so decided to shift my attention onto using that instead. It seems like Bamboo was kinda pushing me in that direction anyhow.

Installing Mocha is done via NPM:

C:\temp>npm install -g mocha
npm WARN deprecated jade@0.26.3: Jade has been renamed to pug, please install th
e latest version of pug instead of jade
npm WARN deprecated graceful-fs@2.0.3: graceful-fs v3.0.0 and before will fail o
n node releases >= v7.0. Please update to graceful-fs@^4.0.0 as soon as possible
. Use 'npm ls graceful-fs' to find it in the tree.
C:\Users\adam.cameron\AppData\Roaming\npm\mocha -> C:\Users\adam.cameron\AppData
\Roaming\npm\node_modules\mocha\bin\mocha
C:\Users\adam.cameron\AppData\Roaming\npm\_mocha -> C:\Users\adam.cameron\AppDat
a\Roaming\npm\node_modules\mocha\bin\_mocha
mocha@2.4.5 C:\Users\adam.cameron\AppData\Roaming\npm\node_modules\mocha
├── escape-string-regexp@1.0.2
├── commander@2.3.0
├── diff@1.4.0
├── growl@1.8.1
├── supports-color@1.2.0
├── debug@2.2.0 (ms@0.7.1)
├── mkdirp@0.5.1 (minimist@0.0.8)
├── jade@0.26.3 (commander@0.6.1, mkdirp@0.3.0)
└── glob@3.2.3 (inherits@2.0.1, graceful-fs@2.0.3, minimatch@0.2.14)

(don't worry about the deprecation warnings, everything still works... this is all just part of a trademark dispute).

And similarly install Chai and bamboo-mocha-reporter.

Another thing I needed to do is to make sure I had my NODE_PATH environment variable set. I was kinda expecting the Node install to do this, but it didn't. For me that needs to point to C:\Users\adam.cameron\AppData\Roaming\npm\node_modules

So a basic Mocha test looks like this:

var assert = require('chai').assert;

describe('MyClass tests', function() {
    var MyClass = require("../myApp/MyClass");
    describe('Baseline', function () {
        it('should exist and be usable', function () {
            var myObj = new MyClass();
            assert.instanceOf(myObj, MyClass, "myObj should be an instance of MyClass");
        });
    });
});

This is a tweaking of the sample they had on their website's "getting started" section:

var assert = require('chai').assert;
describe('Array', function() {
  describe('#indexOf()', function () {
    it('should return -1 when the value is not present', function () {
      assert.equal(-1, [1,2,3].indexOf(5));
      assert.equal(-1, [1,2,3].indexOf(0));
    });
  });
});

Note that the instructions there don't actually implicitly mention the dependency on Chai here, which is a bit crap of them. They seem to kinda assume one knows this. This is not a safe assumption to make.

Another thing that is "interesting" about Mocha is that it doesn't come with any assertion capabilities at all, so one needs to install Chai (or some other assertions lib) for it to be of much use. I guess this is symptomatic of this mania Node apps have for making everything a "dependency" even if it's really more of a necessity. Equally I discovered that Mocha has no mocking framework either (which almost makes the name of the thing a misrepresentation! ;-), so I think I'll be using Sinon for that. But later.

But anyhow, one one installs all that crap, one can run a test.

I've created a basic GitHub repo, JavaScriptTesting, which has a basic class and a basic test of it:

var Person = function(firstName, lastName) {
    this.firstName = firstName;
    this.lastName = lastName;
};

Person.prototype.getFullName = function(){
    return this.firstName + " " +this.lastName;
};

module.exports = Person;


var assert = require('chai').assert;

describe('Person tests', function() {
    var Person = require("../myApp/Person");
    describe('Baseline', function () {
        it('should exist and be usable', function () {
            var person = new Person();
            assert.instanceOf(person, Person);
        });
    });
    describe('Method tests', function () {
        describe('getFullName tests', function () {
            it('should return a full name', function () {
                var person = new Person("FIRST_NAME", "LAST_NAME");
                var fullName = person.getFullName();
                assert.equal("FIRST_NAME LAST_NAME", fullName);
            });
        });
    });
});

And I can now run these from the command prompt:

C:\src\JavaScriptTesting>mocha


  Person tests
    Baseline
      V should exist and be usable
    Method tests
      getFullName tests
        V should return a full name


  2 passing (47ms)


C:\src\JavaScriptTesting>

Cool. So I know the tests work.

Now I go about getting it all to work on Bamboo. I'd not installed this before so I followed the instructions. One pitfall I fell foul of the first time is the requirements state:

Servlet container requirements
You will need a servlet container that supports the Servlet 2.4 specification. Most modern containers should comply with this.

This is from "Bamboo installation guide". So I messed around getting Tomcat installed (which granted is not much messing around), only to find out that's bullshit. Bamboo installs its own instance of Tomcat, and does that out of the box as part of the installer. Oh well: this is not much of a hardship.

I knew Bamboo will be needing to write stuff to disk and do other stuff that the local system account perhaps did not have permissions to do, so I created a specific account for Bamboo (I called it "bamboo" with a password of "bamboo" ;-), and gave that user full access permissions to the Bamboo home directory.

Oh... during install I let Bamboo create its "home" (/working) directory in the default location which - in hindsight was daft both on my part, and on part of the Bamboo installer, cos it created it in my own user account's user directory. That makes no sense for a server-oriented application. So I changed this to be c:\bamboo.tmp (I'll be blowing all this away on this machine once I've done with this article). So it was that dir I gave the Bamboo user full control permissions to.

After that I dropped down to a command prompt (running as administrator) and ran c:\apps\atlassian\bamboo\InstallAsService.bat to install the Windows service, then I edited that to login with the new bamboo account and started it.

Browsing to http://localhost:8085/ yielded success! (I can't show you a screen shot as I forgot to take one at the time, and I cannot get back to that first screen again now. Just tryst me ;-)

Next Bamboo needs some configuration, so I chose the Express object, which just requires me to enter a login and a password and an email address. Then I was in, and it was time to create a new job to run my tests.

I really have no idea what's going on in Bamboo, but I kinda followed my nose.

I created a "project" called "JavaScript App" which was assigned a short code of "JA". As far as I can tell this is just like in Jira when one creates a new project, and it gets that abbreviation which ends up as the prefix to all tickets. But I dunno. I just agreed with what Bamboo suggested. Next I created a "plan" called "JS TDD CI", and that got an abbrev. of "JTC" (f*** knows if any of this will ever be relevant again, but it's what was going on on the screen as I was thinking "yes, lovely, that's nice").



Then we started to do something that seemed useful: I linked the plan to a repository which is where I point Bamboo to my GitHub repository (that JavaScriptTesting one I mentioned further up). All good.




On the next screen I add the other steps to the plan. It's already added the "Source Code checkout" one for me. So running that much would get the source code checked out.

Next I need to tell Bamboo about Mocha and Chai (and its own mocha-bamboo-reporter), so I add three NPM tasks. Here's the screens for adding the mocha one: the others are all the same:





Having done that, I then add the task to run the tests, which is done via the Mocha Test Runner:



And that's it. I can now run the tests by selecting the run option from the top right of the main plan screen. Stuff whirs into action (and it logs an awful lot of stuff), and eventually:



Now I dart back to my other machine and add a new test to my code:

describe('getAgeInYears tests', function () {
    it('should return the correct age in years', function () {
        var person = new Person("FIRST_NAME", "LAST_NAME", new Date("1970-02-17"));
        var ageInYears = person.getAgeInYears();
        assert.equal(46, ageInYears); // obviously this is a poorly-written test, but it works for a few months yet ;-)
    });
});

This fails cos I have not added the getAgeInYears method yet, but for the sake of demonstration I'll push it up to GitHub.

Bamboo is polling GitHub every three minutes, so after a bit a test run starts and...




There's my latest changes breaking the build. I've never been so pleased to see a failing test before. Hang on whilst I implement that method...



Cool.

Now I did have some problems, and I'm not that happy with a coupla things. Firstly I've got all those NPM modules installed globally already, and I have them on my NODE_PATH. But Bamboo refuses to "see" them. It only seems interested in looking in the node_modules dir in its own working directory. I could not work out how to change that.

I did have some success initially with doing an npm link instead of an npm install in my test script, but when I came to test everything today I must have screwed something up as it had stopped working. Using the install approach requires dragging the stuff down off the 'net each time I do a test run, which seems a bit wasteful. I'm sure it's something I'm doing wrong, and when I work it out, I'll update this article accordingly.

Having got this proof of concept running, we are now in the position to give it a go in our actual work environment (which we've done... we've got our first test passing).

I'm pretty pleased about this. I am now in a place with my JavaScript development that I should have been (and wanted to be) about three years ago. But at least I've got there.

Righto.

--
Adam