▶️ Intro On the previous post we started our journey with a very simple scenario, and we used a nice feature of the Go programming language to get a measure of how much % of the target program our test is exercising. This time I am going to experiment a Proof of Concept about how we can obtain a test code coverage metric estimation for a normal binary program, without any recompilation. ...
☂️ Intro When your code includes a suite of unit tests, code coverage is an important metric to measure the test effectiveness and it’s rather easy to obtain; there are plenty of tools around. Image credits to: Nataliya Vaitkevich On the other hand, often we also need to do integration or E2E testing, as in our QA journey we are mostly running real world programs instead of single well-chosen functions. Let’s start with a basic use case, and prepare a simple program tailored for this purpose. ...
💭 What ? Imagine a web server that only starts when someone actually tries to access it. Or a database that spins up only when a query comes in: this is the magic of socket activation. The concept is not new, as old-school sysadmins may are used to see something like inetd or xinetd for on-demand service activation in the past. As some cool projects like cockpit have already started using this little-known feature, in this blog post we’ll see the basics and try to get familiarity with the tooling. ...
👣 Intro Tracing tools are pretty popular in the Unix/Linux ecosystem; for example in the userspace we have ltrace to trace library calls of the programs and strace to dive in deeper and inspect syscall usage. One of the many features that Linux kernel offers since 2008 (then evolved) is ftrace that allows many different kind of tracing at runtime. While not as flexible as eBPF technology, it can be helpful in some occasion and doesn’t require a full fledged programming language. ...