Codegen OutputFormat not respected

[danpalmer]

Bug report

Just came across a small sharp edge in the API for codegen – specifying the OutputFormat has no effect, and the output format (single vs multiple files) is only a property of the URL passed in.

This is noted in a comment in the source code, so seems to already be acknowledged as an issue. Given that the API provided affords that this would work in a particular way, and that it doesn't in fact do this, I think it would be good to fix it.

I can see why it would be nice to be able to express the choice in a way that isn't just part of the URL passed in, but the inconsistency means that the documentation aspect can be incorrect, which I think is worse than not having it.

Suggestions

I'd suggest one of two fixes:

1. Drop the OutputFormat and take a URL, documenting the behaviour given different properties of the URL.
2. Keep the OutputFormat and raise an exception if the URL passed in doesn't conform to expectations.

I think it's nice to have the documentation in the API, and maintaining backwards compatibility is always good, so I'd have a preference for option 2. This exception would also not technically break backwards compatibility as I think the compatibility is framed in terms of documentation rather than behaviour, but please do correct me on this if I'm wrong!

Contributions

Would you accept a PR for this? Can we treat this issue as a design discussion for that contribution?

Versions

• apollo-ios SDK version: 0.34.1
• Xcode version: 12.3
• Swift version: 5.3
• Package manager: SPM

[designatednerd]

Option 2 would definitely be better, IMO. I considered option 1 but I felt like it didn't capture intent clearly enough - throwing an error if a folder URL is passed in for singleFile or if a file URL is passed in for multipleFiles seems like a totally reasonable way of enforcing that.

Would definitely welcome a PR!

[designatednerd]

Let me know if you are planning to make a PR - don't want to step on your toes but I should probably close this loophole 😃

[designatednerd]

Check on this has shipped with 0.39.0!

[danpalmer]

@designatednerd thanks! Sorry for not getting around to doing a PR for this at the time, I have been off for a while. Thanks for going ahead with it though.