Alright, so let me tell you about this whole “chained together checkpoints” business I got myself into. It sounds a bit technical, maybe, but trust me, my journey with it was more about stubbornness and too much coffee than any high-level engineering. I figured I’d share what I went through, because sometimes just hearing someone else’s messy process helps.
The Initial Mess and Why I Bothered
So, I had this personal project I was tinkering with. It wasn’t for work, just something on the side. This thing had several stages – let’s call them Step 1, Step 2, and Step 3. Each step depended on the one before it. Crucially, Step 1 could take a long, long time to finish. If Step 2 coughed and died for some reason, I really, really didn’t want to run Step 1 all over again. That’s where the idea of “checkpoints” came in – basically, saving my work after each successful step.
And the “chained together” part? Well, I wanted the whole sequence to run automatically. Once Step 1 was done and its checkpoint saved, Step 2 should kick off by itself, and so on. I’m not a fan of babysitting scripts, you know? I thought, “How hard can this be?” Oh, the famous last words of every weekend project.
My first attempts were a disaster. I tried some overly complicated scripting, trying to get programs to talk to each other in ways they weren’t really designed to. I had one script trying to launch another, pass some status, check for output files… it was a tangle. Things would fail silently, or one step wouldn’t even realize the previous one had finished. I probably wasted a whole afternoon just on that, getting more and more frustrated.
Hitting a Wall, Then a Lightbulb
I remember staring at my screen, thinking this shouldn’t be rocket science. I was trying to make it too fancy, too integrated. I even fiddled with some ancient batch files at one point – talk about desperation! It felt like I was building a house of cards. One wrong move and the whole thing would just collapse, and I’d be back to square one, probably with less hair.
Then, after stepping away and grabbing yet another cup of tea (switched from coffee, hoping for a different kind of inspiration), it kind of hit me. I was overthinking the “chaining” part. I didn’t need a super-smart orchestrator. I just needed each step to be a bit more self-aware and to pass a very simple message to the next.
How It All Clicked Together (Finally!)
So, what I ended up doing was much simpler, almost embarrassingly so. For each main step (Step 1, Step 2, etc.), I wrote a tiny little wrapper script. This wrapper had a few jobs:
- First, if it wasn’t the very first step, it would check for a “success flag” from the previous step. This flag was just an empty file, like “step1_*”. If that file wasn’t there, the wrapper would just stop and complain. No point in running if the previous part failed or hadn’t run.
- If the previous step was okay (or if it was the first step), the wrapper would run its main task – the actual work of Step 1 or Step 2.
- After the main task finished, the wrapper would check if it actually completed successfully. If it did, it would save the necessary output (that’s the “checkpoint”) and then create its own “success flag” (e.g., “step2_*”).
- Then, it would automatically try to kick off the wrapper for the next step in the chain.
And believe it or not, this clunky-sounding system actually worked! It wasn’t elegant. It wasn’t something I’d put on my resume under “Advanced Process Automation.” But it was robust enough for what I needed. If Step 2 failed, its “step2_*” wouldn’t get created. Step 3‘s wrapper wouldn’t even try to run. I could then go in, figure out what went wrong with Step 2, fix it, and then just manually re-run the wrapper for Step 2. Since Step 1‘s checkpoint and “step1_*” were still there, Step 2 would pick up right where it needed to, without me having to re-do everything.
So, that was my adventure with “chained together checkpoints.” It was a good reminder that sometimes the simplest solution, the one that feels a bit crude, is the one that actually gets the job done. Spent more time fighting my own complicated ideas than building the actual solution in the end. Lesson learned, I guess. Or at least, a story to tell.