Deprecate camel case attributes

[jmks]

Pull Request

Related issue

Fixes #320

What does this PR do?

When calling index#search with non-snake case attributes (e.g. camelCase or weirdMixed_Case) a warning is emitted (to stderr). Here's an example:

Attributes will be expected to be snake_case in future versions of MeiliSearch.

Non-conforming attributes: attributesToHighlight

I have a few questions:

1. Which attributes?

The issue mentioned sending the search attributes. Do you want this deprecation warning for just index#search or all methods (i.e. any caller of Utils.transform_attributes)?

Currently this just handles index#search but should be easy adapt for all callers.

2. The deprecation warning message

I wrote something I would like to see but I'm open to suggestions.

3. Utils.transform_attributes handles an Array argument.

I ran the test suite and did not find an example of an array passed to this function. Do you know when this could be called with an Array argument?

4. I didn't see any examples in .code-samples.meilisearch.yml that needed changing (again, only for index#search).

However, I did update the specs.

Cheers!

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• Does this PR fix an existing issue, or have you listed the changes applied in the PR description (and why they are needed)?
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Thank you so much for contributing to Meilisearch!

[brunoocasali]

Hi, @jmks thank you so much for your contribution! It is amazing!

Let's answer your questions:

Which attributes?

I think we can use the same logic for every method that has a transform_attributes call because the transform_attributes is the one responsible for dealing with the possibility of handling snake/camel casing.

The deprecation warning message

I just sent a recommendation because of the Meilisearch name, but it is ok for me.

Utils.transform_attributes handles an Array argument.

Yeah, I didn't have much context of the code when I wrote it in the first place, but today I don't know any use case for that handler. But to be honest this code will be removed in a couple of releases after the next one, because now we will have the deprecation warning :)

[brunoocasali]

@jmks your PR is approved in any case, but I would like to have the warning in every possible use case, so if you could do this change it would be awesome! :D

[brunoocasali]

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[brunoocasali]

Hi, @jmks do you still have time to finish this PR? Otherwise I can do it anyway :)

[jmks]

Sorry, didn't mean to sit on this for so long. I did start working on it again today and will update the PR in the next day or so.

[jmks]

Hi!

I've updated the all callers of transform_attributes to emit warnings now and updated all the specs to not emit warnings.

But to be honest this code will be removed in a couple of releases after the next one, because now we will have the deprecation warning :)

I'm not sure about that. My impression of this was that in the Ruby code, this is standardizing on snake_case (as per Ruby idiom) but when sending to the Meilisearch server (or receiving responses), the attributes will still be camelCase.

[brunoocasali]

I continued your work in branch #470

Thank you very much for your work, and sorry for taking that long to make this move.