Elasticsearch: Completion suggester docs claim `_source` filters the source but this isn't implemented

[nik9000]

I found this while going through snippets that aren't marked // CONSOLE. In this case the this snippet looks to suggest something that isn't implemented.

[nik9000]

I know @jimferenczi's been working on source filtering lately but the completion suggester is @areek's baby. It looks like this is simply a case of the parsing not being implemented which isn't super difficult to fix so I expect anyone can take it.

[nik9000]

I can also take this if everyone else is busy!

[jimczi]

I don't think it is worth implementing this since the _suggest endpoint will be deprecated in 5.0 (https://github.com/elastic/elasticsearch/pull/20435) and that it works with the _search API ?

[nik9000]

Perfect! So long as we use the _search API in the docs we're all good then.

[russcam]

@nik9000 Completion Suggester documentation still says _suggest supports _source filtering.

Since _suggest endpoint still exists in 5.0, I think source filtering should be included as per the current documentation, to be consistent with suggestions when using the _search endpoint.

[nik9000]

Yeah, if we're going to remove it in 6.0 we don't need docks there but we should fix the docs in the 5.0 and 5.x branch. @russcam, are you willing to open a PR to do it?

[nik9000]

Yeah, if we're going to remove it in 6.0 we don't need docks there but we should fix the docs in the 5.0 and 5.x branch. @russcam, are you willing to open a PR to do it?

Ignore that. I've found a moment so I'll just do it now.

[nik9000]

@russcam I opened #21268.