Custom templates with includes

[tnhirst]

I think this is great little tool, kudos and thanks to @oocx for creating it!

I'm trying to customise the existing template a bit, so I have started by copying over all files in the src/Oocx.TfPlan2Md/MarkdownGeneration/Templates folder to my own local folder and attempted to run with

docker run -v .:/data oocx/tfplan2md /data/tfplan.json --template /data/default.sbn

but I get the error Error rendering template: /data/default.sbn(1,4) : error : Template 'data/_header.sbn' not found. I have a copy of the header template alongside the default.sbn that gets mounted to the /data folder. Am I right in thinking this is an issue with the path that Scriban is trying to find the header template? I notice from the error message that it is looking in data/_header.sbn which I assume is trying to read from /app/data/_header.sbn rather than /data/_header.sbn.

Am I doing something wrong, is this a limitation in using tfplan2md from the docker image where you need to mount your data to an absolute location? I did try mounting my local working directory to the docker image's /app/data but got the same error - it seemed to find the top level template I was using, but that in turn isn't able to find the other templates to include. I also tried updating the include statements to absolute paths, with the same result - Scriban still reported not finding the header at data/_header.sbn even as I specified /data/_header.sbn

[oocx]

Hi @tnhirst,

I think there is currently a bug in the template loader and using custom templates is currently broken.

What are you trying to change in your customization? If it's something that could be useful in general, I might just add it to the default template.

Up until your question here, I thought nobody was using custom templates yet and I was actually considering to remove scriban and templates altogether, as it currently causes more headaches than actual value (for my personal use cases).

[tnhirst]

Thanks for the reply @oocx!

We are actually using Terragrunt (which I saw came up in another discussion) and have recently moved to using Terragrunt's explicit stacks. What that means is that we have many plans rather than just one. When I was trying out tfplan2md last week I got all of the plans' markdowns concatenated into one long output, with the path to the plan as a separator with an h1 header.

The output is great, but most of our units will have no changes most of the time, but the plans still have plan outputs. It makes it a little less easy to scroll through the output and pick out unit that have changes than I would like.

What I was going to try next was customise the template so that if a unit's plan has no changes then the only markdown is 'No changes', skipping all of the other outputs so that we could easily scan through the report and see units with changes. My next build on that was going to be seeing if I could inject the path to the plan in question into the template to use that as a part of the message (something like No changes in qa/london/.terragrunt-stack/back-end/.terragrunt-stack/account-service/tfplan.json) or even a parsed version of it so that the message could be something like qa -> london -> back-end -> account-service: No changes)

That's what motivated my question - you'll have more of the context about what it would take to achieve either of those two steps, and what the other options are. Unless there's a big take up in using Terragrunt the same way, then it might be too niche to add to the default template. I have never used Scriban before but looking at what you have it seems like a nice templating language. I can certainly see why you thought having customisable templates would be valuable but I guess it does depend on how much they are being used!

If this is a bug in the template loader, I'm happy to open an issue, and whilst I don't have an awful lot of time on my hands right now, pitch in if I can (and of course, if you decide to keep the custom templates and it's worth it!)

[oocx]

@tnhirst I think we can find a solution without custom template. We have to - I just had a big refactoring where I removed scriban. That made the code much easier to understand and test, fixed many minor inconsistencies and reduced the docker image size from 7 MB to 21, MB :)

• One thing that is already supported is a custom h1 title via the --report-title argument.
• I could also add a cli argument that would tfplan2md return different exit codes, depending on if there are changes or not. If tfplan2md sees the plan has no changes, your concatenation logic could simply concat a "no changes" message instead of the actual output

Would that solve your use case?