Co-op at Research In MotionPublished 2013/01/11
This post was originally published on WordPress in January of 2013.
When I was in the fifth grade, I bought a copy of Interplay's "Learn to Program Basic" from a Scholastic magazine flier.
It was terrible.
The characters were confusing, the cut scenes increasingly maddening, and yet, I fell in love with programming. This was the type of interactive tutorial finally perfected by sites like CodeCademy that held your hand while you learned all about the intricacies of variables and functions. The animated tutor who had a CD-ROM for a face and a dog for a companion would encourage you as you stepped through the levels, creating games and animating sprites. Now I finally had a reason to use the beast of a computer my parents had been so good to invest in, one of those ridiculously expensive towers that had a couple megabytes of memory and a processor that was still measured in megahertz. Over the next few years I would try my hand at controlling my computer using the-little-black-box, copy/pasting HTML, and (finally) Python.
Computer Science in university is what I was after all along. Here I can spend long nights writing code with likeminded friends, making terrible jokes, and delivering software that I'm proud of. This will mark the start of my fifth semester at the University of Guelph, and having just spent the last eight months on my first work term with Research In Motion, I'll be coming back even more prepared.
RIM has taken a lot of grief in the news in recent years for largely ignoring the increasing market for smartphones, as such I wasn't sure what to expect of the general atmosphere upon arriving, but I was impressed. The software developers I was working with were optimistic about the new direction the company was heading, my manager Tony Bridges was downright ecstatic at times about the new features being developed, and it was infectious. While not working directly on these new features ourselves, we were responsible for the Continuous Integration (CI) of new work.
CI is crucial, the programmers are responsible for taking all of the work R&D is doing and making sure that it's not going to go ahead and break all of the existing code. Every time a developer submits something new, its our job to take it, compile it, test it, and figure out what breaks. RIM is a huge company, and starting my first real foray into the world of software production seemed daunting: where could I find definitions for all of the Three Letter Acronyms? who could I ask about this specific line of code? how many servers does a company really need?
Sometimes, eight months didn't seem long enough.
Research In Motion
"Research In Motion (RIM), a global leader in wireless innovation, revolutionized the mobile industry with the introduction of the BlackBerry® solution in 1999.
The BlackBerry product line includes the BlackBerry® PlayBook™ tablet, the award-winning BlackBerry smartphone, software for businesses and accessories. BlackBerry products and services are used by millions of customers around the world to stay connected to the people and content that matter most throughout their day."
Research In Motion
RIM can be thought of as divided into two main sections: Devices and Enterprise. I worked for the latter half of the company. The Blackberry line of products has been an industry standard for years now, controlling a huge section of corporate devices that are trusted for their reliability and their security.
RIM is spread out over a number of countries and towns, I undertook my work term at the main headquarters in Waterloo, ON. There are over 20 RIM buildings scattered across Waterloo, congregated around RIM Park (near Laurier University) and Northfield Campus (north of the city). One of our team members even worked in Mississauga and video called every morning for our daily meeting.
My official title was Software Developer for Continuous Integration. My immediate team consisted of X people: myself, my manager Tony, coworkers Mike, Bart, Yuhui, Richard, and Lawrence (a Guelph student as well, and a friend). Beyond that we had help from others who had expertise in specific areas such as machine configuration, build server maintenance, web design, and proxy management. At RIM, if you don't know how to do something, there seems to always be someone who does, and email rules all.
What is Continuous Integration?
Have you ever gotten exhausted tracking down a bug in your code when you threw in a new module?
Have you ever been flustered trying to find a revision of your program that you know is going to work? That's where Continuous Integration (CI) comes in.
As a CI developer I was responsible for three main things:
- Aggregate all of the developers code
- Compile and test the code
- Generate meaningful statistics from the test data
We went through quite a few systems at each of the three steps trying to achieve a good balance while I worked at RIM. None of them perfect. When it comes to CI it tends to be a matter of tradeoffs: do you want lots of speed or lots of customizability?
This step is commonly known as source control. At the university I gained some experience with Subversion and the svn command line client, at RIM they prefer Perforce. Perforce is the brute force revisioning system, anything you could possibly think to do with it is possible. Want to see a list of users that modified a file after it was branched but before it was merged into another repository? No problem. Because of these features perforce can get a little slow, especially when you have a bunch of developers all syncing down the latest code for an entire project, but the GUI more than makes up for it.
Compile and Test
This is generally where things get tricky. When you have a large project with lots of moving parts, you need to create a “build contract" to keep track of how everything fits together. Sometimes a module in one piece of the project will require a specific version of another piece, but only at a certain step in the compilation. Build contracts come in many different shapes and sizes, but they all accomplish the same thing: a blueprint for compiling and testing code. Since we worked with a lot of Java code, we had a lot of options to pick from.
Ant gives the user complete control, it's written in XML, and there's a vast library of modules to support any function you can think of. Written by Apache, at first glance it appears to be the best tool for the job. But Ant has it's downfalls: while XML gives it a good structure, it makes it much harder to read an maintain, a lot of the libraries are buggy and missing features, and it tends to be much lower level than other build solutions. Ant calls it's functions “targets" and you can nest them however you like. They can invoke system commands, move files, connect to remote servers, and - of course - compile your program. Ant is best suited to projects that need to be highly customizable.
The next option is Maven, also by Apache. Maven sought to do fix everything that Ant did wrong, bringing a much more high-level approach to build systems. Ant is to C, what Maven is to Python. Maven build contracts are also made from XML but in a much more structured way. Where Ant used XML tags to denote everything from variables to boolean expressions, Maven has a rigid definition of which tags are expected at each step. A maven contract is called a Project Object Model (POM) file, and it generally will list: which repositories to grab source from, dependencies for each module, needed plugins, and where to publish the results. At the expense of it's shallow learning curve, Maven isn't quite robust enough to easily work with low level processes, the only way to customize your contract is to write an entire Java plugin to accomodate your function. The documentation can be rather sparse.
Last and certainly not least, I got a chance to work with Gradle. Gradle succeeds where the aforementioned fail by striking a harmonious balance between high and low end. Gradle is - in fact - just an extension of the Groovy programming language (which in turn, is an extension of Java). The syntax that Groovy and Gradle use was completely new to me, there is a great deal of emphasis on Lambda functions, closures, and associative arrays. It is a wonderful Object Oriented tool and has a special focus on collections of objects. The syntax isn't quite procedural, and at times doesn't quite look like OO either, it definitely takes a while to get used to but it is well worth the investment.
A part so crucial it required a team member's (mostly) undivided attention. Bart was a wonderful colleague who was primarily responsible for analysis of data coming out of test runs and finding new and inventive ways to shape that data. Used properly it can show how a project is progressing over time, and how various patches have effected the stability. The data was then used to create numerous graphs that demonstrate the project's state and made available on a local site. Since a build is started whenever developers submit new code into the repositories, we had the system automatically email them on completion showing the effects of the new code.
Time Well Spent
In a continuous integration environment the main line of work is responding to problems and finding fixes to broken software. That being said, there were three additional projects amongst which I divided my time while in Waterloo.
In build system management, a collection of computers that is required to compile, analyze, or test software is referred to as a 'Lab' (or a 'Pool'). These labs are composed of any number of devices, each with specific functions that can be used. A typical lab might consist of 3 machines used to compile 3 different modules of a program, a repository that has a source code management (SCM) system for developers to push code to, and an artifact repository (such as Artifactory or Nexus) to push the completed code to. Devices might also be needed (for RIM this would include phones and tablets) to test functionality of certain modules.
All of these lab devices need to be configured in special ways so that a 'Master' device can distribute tasks amongst them. That's where I come in. My job was to configure each of the machines in a lab including (but not limited to): setting up public/private authentication keys, adding new software, managing configuration files, and ensuring network connectivity. Throughout this I learned a great deal about windows services, network connection protocols (RDP and SSH), and batch file editing (korn shell and batch).
Build Time Versioning
Tech companies will often have an 'internal' name for products before they are officially named by the marketing division and released into the wild. This, however, can raise some problems when writing the software itself - what if the product name is required on a splash screen? do we have to change code at the last minute?
One thing I was surprised at working in a big company was how frequently product names can change. Managers are constantly changing their mind or trying to re-name a product to fit with new designations. With that being said, we need a way to rapidly re-name or re-number a product. My task for this was to come up with a way to keep a very small file, containing only the product name and version number, and be able to inject this into the compilation process to have it show up in the final product. I worked closely with the installer team to create a very small XML file that resides in an SCM branch (for version tracking) and can be edited by a select few managers. When the product we were working on was being compiled, a script I wrote in Groovy would be called with the XML as a parameter. The script would then generate a number of data files that could be compiled with the source code and would properly update the new name/version in all the right places.
RIM's products are massive and have a huge number of pieces involved, so trying to track down all the places where I would need to inject the right values was exhausting, but in the process I learned about some great shell tools for code analysis that I'll never forget. Among them, my new favourite tools: xargs, sed, awk, and grep.
Learn them. Use them. You won't regret it.
The projects I have coded in university classes tend to be relatively small - they don't take more than a couple minutes to test and can generally be compiled in mere seconds.
Big software takes a bit longer.
Some of the projects we were responsible for compiling had upwards of 10 sub-projects (think of them as really big modules) and could take over 10 hours to compile, test, and publish. Bearing that in mind, sometimes a project might fail the very first test but keep going until all are finished, but a developer shouldn't have to wait till the very end to find out. This called for some innovation, and a way of tracking build status in real time. Our solution was to create a library of logging functions that would communicate with an SQL database (via a logging proxy) that fed a status-monitoring website.
I was in charge of the logging functions. Given a set of specifications of what the proxy server expected, I was able to create a Perl module of functions that would send an XML query to the server, notifying it of the current build status. This could mean telling it that a brand new project was being compiled, a specific module just passed a specific test suite, or that a recently launched build is failing (or has failed completely!) Having never worked much with Perl before, this library had a but of a learning curve, but I found that my knowledge of Python was quite transferrable and didn't hit too many roadblocks. The big time sink on the project was the constantly changing requirements for what the library should be able to do. After it was written and communicating well with the server I had to sprinkle the compilation code with the appropriate new logging functions.
Noun: A person who knows many languages.
Polyglot is my new favourite word, and I think all programmers should strive to be one. Different programming languages offer different features, each with their ups and downs, but the more you learn the more tools you have available for any software job.
If all you have is a hammer, everything looks like a nail.
Perl is the eminent scripting language of old that Unix gurus and script-kiddies alike have been using to parse, replace, and refine their code for years now. It's found a niche in almost every conventional code usage and, once you get comfortable with some of it's more obscure syntax (\$|=1 anyone?) its really quite simple. Perl modules are similar to C's pre-compiled dll's and can be handy in adding extra functionality to small scripts, the support for some object oriented functionality was vital in my work to create a logging library. I also began using perl for everyday work to automate certain batch processes intelligently and scan vast file repositories for code segments.
Groovy is Java's cool new grandchild. First appearing in 2003, Groovy sought to add new scripting functionality to Java to allow for awesome concepts like closures and dynamic collections. I used Groovy for generating code templates from an XML data file but it's uses are virtually limitless when you consider that any existing Java libraries can instantly be included to expand functionality. There are also libraries written exclusively for Groovy itself but - be forewarned - the documentation is sparse and oftentimes incomplete.
Having only worked with Bash (Bourne Again SHell) before, I was confused when I started seeing the .ksh extension scattered throughout some builds. I need not have worried, the syntax is almost exactly the same for the basic functions. Where Korn Shell really shines is when it comes to variable management and regular expressions, a place where shell scripting has traditionally fallen short. A long article found here, shows the vast scope of manipulative methods that Korn Shell affords it's users to quickly find and replace patterns. I've never come across a system that uses Korn Shell by default, but I've since installed it on a Linux box of my own for scripting at home.
Ant is Apache's tool for re-inventing the makefile on a Java platform. It's a swiss army knife for automatic software builds, but keep in mind, even a swiss army knife has pointy bits to accidentally stick yourself with. The first issue is the inherent issues associated with XML - the markup in which Ant is written. More often than not the invoking process will fail not on bad code, but due to an improper structure or missing right bracket. For all of it's quirks though Ant is a fun example to learn with for scientifically-oriented minds as the focus of XML forces the user to structure things logically. Beware when using Ant for larger projects, you may get lost in the spaghetti code.
Maven exists on the other end of the spectrum for Apache's build tools. It is explicitly high level definitions of a projects structure, trusting to the built-in compile, test, run tools that Maven provides to handle the actual compilation. This allows for greater abstraction of the actual compilation and testing process, while making it obvious which modules depend on which. If you really want to emulate the swiss army knife behaviour of Ant, Maven will at least force you to create your new functionality in a Java class and include it as a plugin, in the hopes that this will put an onus on the developer to write good re-usable plugins. RIM utilized a variety of homemade plugins for Maven tooling and I became familiar with a few of them. Maven is the best tool for leviathan software projects.
I didn't spend as much time with Gradle as I would have liked to, and only managed to write one or two scripts, but I feel that it would serve my current software purposes well. Independent of Apache, this tool is the average of Ant and Maven, quirks and all. The structure is more akin to a makefile than any other build languages that I've worked with before and attributes this to it's core of interpretation using Groovy syntax. This is largely left up to personal preferences, as there are a thousand different ways to tackle any given job using Gradle, and sometimes not enough ways to handle something that seems simple. Underlying it all is the concept of a project lifecycle and a developer would do well to have a firm understanding of that before attempting any of the more obscure commands.
I would like to personally thank my manager Tony Bridges and close coworker Mike Dobrindt. You were both imperative to my understanding of how our division fit into the organization.
Thank you to Bart whose patience and thinly veiled threats were crucial in keeping me on track with the logging library development.
Thank you to Richard, a fellow coop whose terrible sense of humour always helped to lighten the mood when the workload got heavy.
Thank you to Yuhui, a fellow coop whose unfailing friendliness was always appreciated.
Thank you to Lawrence for making the carpool more bearable.
Thank you to both Cheryl Hulme and Laura Gatto for their help in all things coop related and helping to arrange for the position.
And of course, thank you to everyone else at RIM.