I haven’t got much experience when it comes to testing web applications. Instead (and more so out of apathy than belief), I’ve always adhered to the ad-hoc test approach. However, the usage of pure Posgres unit tests back when I worked on a complicated investment database with Halfgaar did teach me the advantages of test-driven development.
For payformystay, though, unit tests simply won’t cut it. The database design is quite straight-forward with not that many relationships and the schema’s only complexities arise from it being remarkably denormalized and full of duplication. Besides and contrary to mine and Halfgaar’s PostgreSQL project for Sicirec, the business logic doesn’t live all neatly and contained on the database level. And I’m not using a clean ORM wrapper either, which I could use as a unit test target. And what would be the point, since in typical MySQL/PHP fashion it would be much too easy to circumvent for a particular function.
What I want for this application is full functional test coverage so that I know that all parts of the website function correctly in different browser versions across operating systems. In other words: I want to know that the various parts are functioning correctly as implied by the fact that the whole is functioning correctly.
But how do you do automated tests from a browser?
At first, I thought I should probably cobble something together myself with jQuery, maybe even using a plugin such as Qunit with the composite addon.
Then, there’s Selenium which is a pretty comprehensive set of test tools, meant precisely for what I need. Sadly my wants weren’t easily aligned with my needs. Hence, it took me some time (months, actually) before I was sure that Selenium was right for me.
Selenium versus my pipe dream
Selenium IDE is a Firefox extension which lets you develop Selenium scripts by recording your interactions with the browser. It stores its script in “Selenese”. This held quite some appeal to me, because my initial testing fantasy revolved around doing it all “client-side”, in the sense that I wouldn’t have to leave my browser to do the testing. I wanted to be able to steer any browser on any machine that I happened to stumble upon at my test site and fire those tests.
I had to eventually replace my pipe dream with the question of which WebDriver implementation to use and which testing framework to use to wrap around it.
I thought PHPUnit had some serious traction, but seeing that it had “unit” in its name, I thought it might not be suitable for functional testing. The documentation being unit-test-centric, in the sense of recommending you to name you test cases “[ClassYouWannaTest]Test” didn’t help in clearing the confusion.
Luckily, I came across an article about acceptance testing using Selenium/PHPUnit [acceptence test = functional test].
I’ve since settled on PHPUnit by Sebastian Bergmann with the Selenium extension also by Bergmann. His Selenium extension provides two base TestCase classes: PHPUnit_Extensions_SeleniumTestCase and PHPUnit_Extensions_Selenium2TestCase. I chose to use the latter. I hope I won’t be sorry for it, since it uses Selenium 2’s Selenium 1 backward compatible API. Otherwise, they’ll probably have me running for Facebook’s PHP-WebDriver in the end. (PHP-Webdriver also has a nice feature that it allows you to distribute a FF profile to Selenium Server/Grid.)
But what about my pipe dream?
If only I’d be able to visit my test site from any browser, click a button and watch all the test scripts run, the failures being filed into the issue tracker (with error log + screenshot) and a unicorn flying over the rainbow…
Anyway, it’s a pipe dream and the best way to deal with it is probably to put the pipe away, smoothen the sore and scratch the itch.
As customary for PEAR projects, PHPUnit and its Selenium extension have quite a number of dependencies, meaning that installing and maintaining them manually in my project repo would be quite a pain. I’ve used the pear command to install everything locally, but my hosting provider doesn’t have all these packages intalled, so if I want to run tests from there (calling Selenium Server here), I’ll have to manage all that pear pain along with my project files.
Doesn’t PEAR offer some way to manage packages in any odd location? I’m not interested in what’s in /usr/share/php/. I want my stuff in ~/php-project-of-the-day/libs/
So far, I’ve remotely hosted both the production and the development version of payformystay, which is specially nice if you want to share development features with others. Now, it’s difficult to decide what’s more annoying:
- Creating a full-fledged, locally hosted version of the website, so that I can execute the tests locally as well as host the testing version (Apache+PHP+MySQL) locally. A lot of misleading positive test results assured due to guaranteed differences between software versions and configurations
- Installing all the PEAR packages remotely so that I can run the test from my hosting provider’s shell. This implies having to punch a hole through the NAT wall at home or anywhere I happen to be testing at any moment. Bad idea. I don’t even have the password to all the routers that I pass during the year.
- Running the development version of the website remotely, but running the tests locally so that there are no holes to punch, except that I’ll have to tunnel to my host’s MySQL process because my tests need to setup, look-up and check stuff in the database. At least, now I don’t have to install server software on my development machine and need only the php-cli stuff.