Joël has been fighting a frustrating bug where he's integrating with a third-party database, and some queries just crash. Stephanie shares her own debugging story about a leaky stub that caused flaky tests.
Additionally, they discuss the build vs. buy decision when integrating with third-party systems. They consider the time and cost implications of building their own integration versus using off-the-shelf components and conclude that the decision often depends on the specific needs and priorities of the project, including how quickly a solution is needed and whether the integration is core to the business's value proposition.
Ruby class instance variables (https://www.codegram.com/blog/understanding-class-instance-variables-in-ruby/)
Build vs Buy by Josh Clayton (https://thoughtbot.com/blog/build-vs-buy-considerations-for-new-products)
Sustainable Rails (https://sustainable-rails.com/)
Transcript:
STEPHANIE: Hello and welcome to another episode of The Bike Shed, a weekly podcast from your friends at thoughtbot about developing great software. I'm Stephanie Minn.
JOËL: And I'm Joël Quenneville. And together, we're here to share a bit of what we've learned along the way.
STEPHANIE: So, Joël, what's new in your world?
JOËL: My world has been kind of frustrating recently. I've been fighting a really frustrating bug where I'm integrating with a third-party database. And there are queries that just straight-up crash. Any query that instantiates an instance of an ActiveRecord object will just straight-up fail. And that's because before, we make the actual query, almost like a preflight query that fetches the schema of the database, particularly the list of tables that the database has, and there's something in this schema that the code doesn't like, and everything just crashes.
Specifically, I'm using an ODBC connection. I forget exactly what the acronym stands for, Open Database connection, maybe? Which is a standard put up by Microsoft. The way I'm integrating it via Ruby is there's a gem that's a C extension. And somewhere deep in the C extension, this whole thing is crashing. So, I've had to sort of dust off some C a little bit to look through. And it's not super clear exactly why things are crashing. So, I've spent several days trying to figure out what's going on there. And it's been really cryptic.
STEPHANIE: Yeah, that does sound frustrating. And it seems like maybe you are a little bit out of your depth in terms of your usual tools for figuring out a bug are not so helpful here.
JOËL: Yeah, yeah. It's a lot harder to just go through and put in a print or a debug statement because now I have to recompile some C. And, you know, you can mess around with some things by passing different flags. But it is a lot more difficult than just doing, like, a bundle open and binding to RB in the code.
My ultimate solution was asking for help. So, I got another thoughtboter to help me, and we paired on it. We got to a solution that worked. And then, right before I went to deploy this change, because this was breaking on the staging website, I refreshed the website just to make sure that everything was breaking before I pushed the fix to see that everything is working. This is a habit I've picked up from test-driven development. You always want to see your test break before you see it succeed.
And this is a situation where this habit paid off because the website was just working. My changes were not deployed. It just started working again. Now it's gotten me just completely questioning whether my solution fixes anything. The difficulty is because I am integrating [inaudible 03:20] third-party database; it's non-deterministic. The schema on there is changing rather frequently.
I think the reason things are crashing is because there's some kind of bad data or data that the ODBC adapter doesn't like in this third-party system. But it just got introduced one day; everything started breaking, and then somehow it got removed, and everything is wo