Use --stringify in remarshal

[Mr-Andersen]

I've got this error: Error: Cannot convert data to JSON (Object of type datetime is not JSON serializable), coming from remarshal. Fixed it in this commit. Fix was tested in local environment

[cdepillabout]

@Mr-Andersen Do you have an example of your stack.yaml / stack.yaml.lock that is triggering this problem?

I didn't realize this, but it appears there is some notion of dates within yaml files? https://yaml.org/spec/1.2.2/#tags And by default remarshal tries to parse these and output actual dates in the resulting JSON, but fails because JSON doesn't have a concept of a date?

The --stringify option on remarshal has the following documentation (https://github.com/remarshal-project/remarshal):

  -k, --stringify       turn into strings: boolean and null keys and date-time
                        keys and values for JSON; boolean, date-time, and null
                        keys and null values for TOML

From this definition it sounds like in addition to turning date-time keys and values in strings, it also turns boolean and null keys into strings? I guess this is alright and wouldn't cause a problem anywhere?

[Mr-Andersen]

Do you have an example of your stack.yaml / stack.yaml.lock that is triggering this problem?

Here is the file: https://github.com/commercialhaskell/stackage-snapshots/blob/master/nightly/2024/11/9.yaml. I guess this is the problematic line.

I guess this is alright and wouldn't cause a problem anywhere?

YAML doesn't have non-string keys, as far as I know, so it should be OK.

[Mr-Andersen]

Oh, to be clear: my stack.yaml was just resolver: nightly-2024-11-09. That's the important part :) You can reproduce it locally, I'm sure.

[Mr-Andersen]

Oh, I tried switching back to LTS (lts-22.41) and your branch and it happens with LTS too. I'm guessing stackage adds this date now everywhere?

[cdepillabout]

@Mr-Andersen Thanks a lot for fixing this and giving an example where it fails!

I submitted a bug upstream to remarshal, since it seems quite surprising that this --stringify option isn't the default: remarshal-project/remarshal#53

[cdepillabout]

Hmm, so it looks like remarshal only got this new --stringify argument starting in 0.17.0, so we'll have to put in a conditional to only include the --stringify argument in newer versions. This is quite annoying. I should really just rip out remarshal and go with a better tool.

[cdepillabout]

@Mr-Andersen I pushed a commit only conditionally using --stringify if remarshal is new enough. Can you confirm this works for your setup?

[Mr-Andersen]

Yep, it works :)

[cdepillabout]

Thanks! I've released this as https://github.com/cdepillabout/stacklock2nix/releases/tag/v4.1.0

[Mr-Andersen]

Thank you for making such simple and well-documented tool! A breath of fresh air after haskell.nix :)