feat: add csv influx v1

[JeanArhancet]

This PR is Part of #24770

Goal: Extend current v1 implementation to support CSV format.

• Added QueryFormat enum to handle CSV, JSON, and pretty JSON formats.
• Refactored conversion of QueryResponse to Bytes to include CSV support.

Check-list:

• I've read the contributing section of the project README.
• Signed CLA (if not already signed).

[hiltontj]

Hey @JeanArhancet - thanks for opening the PR! If it is still WIP, then I suggest converting it to Draft. Then, once you're happy with it, you can flip it back to open and request review from myself or one of the other maintainers.

Also, CI runs cargo commands (clippy, fmt, test, etc.) on the latest version of Rust, so it may help to have the latest version in your development environment as well, i.e., run

rustup update stable

Looks like you need to check clippy and are also getting an audit failure. The latter can usually be fixed with a cargo update from the root of the repository.

[pauldix]

The v1 API of InfluxDB only supports JSON and JSON Pretty. For other formats, we've added the /api/v3/query_influxql endpoint which can return in JSON (not the same format as the v1 JSON), JSONL, Pretty Print (useful for printing to a terminal), CSV, and Parquet.

I'd prefer not to add anything new to the v1 API. It's there for backward compatibility to help people upgrading. But for new functionality, users will have to move to the v3 APIs.

[pauldix]

Actually, @hiltontj just let me know that we already support pretty in the v1 API. So I think we can close this out in favor of users hitting /api/v3/query_influxql for alternative format.

Thanks for pitching in @JeanArhancet. We're still very early and haven't been taking outside contributions so we haven't ironed out that process yet. We'll update our CONTRIBUTING with a little explanation. The high level is that people should always start with an open issue if they want to contribute. If no issue exists for what they want to add, opening an issue is the best starting point so that we can comment there before implementation.

[pauldix]

Ah, @hiltontj just now reminded me that v1 does in fact support CSV. I had forgotten and when I took a look at the docs before closing out this PR, I couldn't find mention of it. However, it's here: https://docs.influxdata.com/influxdb/v1/tools/api/#request-query-results-in-csv-format.

And the issue we had open was here: #24770.

So I'll re-open, assuming you're trying to support that format. If not, and you're just looking for InfluxQL and csv results, v3 is probably what you want.

[JeanArhancet]

Thanks for your feedback, @hiltontj . The PR is ready to be reviewed.

@pauldix Yes, the goal of this MR is to cover the CSV format as in Influx v1.

[hiltontj]

I have a few comments in line for you to take a look at before approving.

[JeanArhancet]

Sorry for the delay, @hiltontj . I have applied your feedback and also fixed the code and added integration tests for this part. What do you think?

[hiltontj]

@JeanArhancet I will try to get some time today or tomorrow to take a look at this, but in the meantime, CI has a cargo-audit failure, which can usually be resolved by doing a cargo update and then commit/push.

[hiltontj]

@JeanArhancet - it's looking great! I left one minor nit in a comment but otherwise LGTM, thanks for sticking with it.

[hiltontj]

Merged! Thank you @JeanArhancet, again, for your PR 🙏