What does it mean for something as complex and dynamic as a platform to be “well-tested”? The answer goes beyond simple functional coverage.
Testing has been my specialty through much of my 14 years of experience in software. If there is one thing I’ve learned about testing, it is that tests can, and should, do more than just test. Tests can be used to communicate and collaborate. Tests can also be used to discover what your product is, as well as what it should be. At their best, tests can be the frame of reference that anchors a team and solidifies team goals into verifiable milestones.
Testing the platform
The Knewton platform is composed of many component services. Each of those services is developed by a dedicated team, and each service is tested on its own with the standard unit, integration, and performance tests. This article is not really about those tests but about how we test the platform as a whole.
The Knewton platform uses data to continuously personalize the delivery of online learning content for individual students. The platform determines student proficiencies at extremely detailed levels, provides activity recommendations, and generates analytics. To do all this, our platform must be fast, scalable, and reliable. Our team must be skilled at grappling with intricate technical problems, while maintaining high-level perspective and focus on the greater system. Testing is part of how we maintain this dual perspective.
Accessibility is the most important criteria we build into our tests to help us achieve the above goals.
In the context of a full-stack test suite, accessibility to me means at least the following:
– Anyone can run the tests
– Anyone can read the test report and analyze test failures
– Anyone can read, change, extend, or otherwise interact with the test definitions
Making tests accessible and promoting those accessible tests can be a tough cultural challenge as well as a tough technical challenge. But the cost of failing at this is high. The more isolated your test suite (and the engineers who create and execute it) are, the less value you will derive from it. Your tests will not reflect involvement from the greater organization, and more importantly, the information your tests generate will not be as widely disseminated throughout the organization as they could be.
So how is a test suite made “accessible”?
Anyone can run the tests
The best thing you can do with a test suite is get it running in your continuous integration server. At Knewton we use Jenkins as our CI server. Anyone in our organization can use Jenkins to invoke the tests against any testing environment, at any time, without any special setup on their computer whatsoever.
Additionally, the test code is in our Git repository, and everyone is encouraged to check it out and invoke the tests in very flexible ways. Developers have the option of running a single test, a set of related tests, tests that correlate with a given JIRA ticket, or other options. Developers can run the tests against a local development environment, or a deployed environment. A test suite that can be run in flexible ways is an important part of accessibility.
Anyone can read the test report
Our test suite produces several kinds of test reports. The report I enjoy showing off the most is the HTML report, which lists every test that runs and details every test that fails (this capability is built into the wonderful RSpec testing framework we use). This HTML report is archived in Jenkins with every test run, so anyone can read it for any test run right within their browser. And because the report uses plain English, it is comprehensible by anyone who is familiar with our platform’s features, developers or not.
Here is what a small portion of our HTML test report looks like, showing both passing and failing tests:
What may or may not be obvious here is that tests are really about information. When I test a piece of software, my product is actionable information. When I make an automated test suite, my product is an information generator. Building a generator of information is one of the more valuable and interesting bits of work a QA engineer can do; here at Knewton, we encourage this mentality.
Anyone can change the tests
First and foremost, my job at Knewton is to enable tests to take place easily. Secondly, my job is to assist and initiate the creation of actual tests. Here at Knewton, it’s great for me to see the testing framework I created be picked up by developers, changed, extended and generally used. While we do formal code reviews on the tests, we try to make that process very efficient in order to ensure that there are very low barriers for anyone who creates a platform test.
What does accessibility get you?
Here are just a few of the ways that an accessible test suite brings value to an organization:
-Raising awareness of the behaviors of the system and the interactions between various components in the system throughout the entire organization.
-Eliminating bottlenecks when releasing: got the code deployed and need to run the tests? Just go press the button.
-Enabling continuous deployment: when your tests are in your continuous integration system, it becomes easy to chain together build, deploy, and test plans into a continuous deployment scheme (we are still working on this one).
-Encouraging better tests: when non-testers are encouraged to get involved in testing, unexpected questions get asked.
More to come
Testing is a massively important part of the puzzle for Knewton as we scale our technology and our organization. We are learning more every day about how to make the best, most accessible and valuable tests we can. In a future post, I intend to share some of the technical details and tools we have been using to make our tests. In the meantime, I welcome your feedback on the ideas presented here and around testing in general.
What's this? You're reading N choose K, the Knewton tech blog. We're crafting the Knewton Adaptive Learning Platform that uses data from millions of students to continuously personalize the presentation of educational content according to learners' needs. Sound interesting? We're hiring.