Fix issue caused by 7.x breaking change (_source_include/_source_exclude)

[XD-DENG]

In documentation, _source_exclude/_source_include are still listed as parameters of a few methods (e.g. https://elasticsearch-py.readthedocs.io/en/master/api.html?highlight=get#elasticsearch.Elasticsearch.get ), while _source_excludes/_source_includes are not mentioned at all.

However, Elasticsearch 7.x ONLY accepts _source_excludes/_source_includes. _source_exclude/_source_include will cause exception on Elasticsearch 7.x. Hence, when I tried to follow the API documentation, I encountered error like the one below.

RequestError(400,
'illegal_argument_exception',
{'error': 
{'root_cause':
[
{'reason':
   'request [/xxxxxx] contains unrecognized parameter: [_source_exclude] -> 
   did you mean any of [_source_excludes, _source_includes]?',
   'type': 'illegal_argument_exception'}], 
   'type': 'illegal_argument_exception',
   'reason': 'request [/xxx] contains unrecognized parameter: [_source_exclude] ->
   did you mean any of [_source_excludes, _source_includes]?'},
   'status': 400}
)

Given recommended client version is quite clear (https://github.com/elastic/elasticsearch-py#compatibility), the solution can be simply replace all _source_exclude/_source_include with _source_excludes/_source_includes.

Reference:

• https://www.elastic.co/guide/en/elasticsearch/reference/6.6/breaking-changes-6.6.html#_deprecate_literal__source_exclude_literal_and_literal__source_include_literal_url_parameters
• https://www.elastic.co/guide/en/elasticsearch/reference/7.0/breaking-changes-7.0.html#source-include-exclude-params-removed
• Support _source_includes / _source_excludes parameter as of ES 6.6 #915
• 1afceba

[elasticmachine]

Since this is a community submitted pull request, a Jenkins build has not been kicked off automatically. Can an Elastic organization member please verify the contents of this patch and then kick off a build manually?

[philkra]

LGTM

[philkra]

Jenkins test this please

[philkra]

@XD-DENG , thank you for your contribution

[XD-DENG]

Thanks @philkra for merging this.