Search request with body is missing transfer-encoding or content-length

[zerkms]

Summary of problem or feature request

It was raised before #737 but closed without further discussion.

It is indeed allowed to send body with GET method.

The problem is that as long as you provide one you must then specify either Content-Length or Transfer-Encoding or both (https://tools.ietf.org/html/rfc7230#section-3.3)

None of those are provided.

So as expected proxies go crazy, since then there is no way to infer the body length, hence return HTTP 411

Code snippet of problem

System details

• Operating System N/A
• PHP Version N/A
• ES-PHP client version 6.1.0
• Elasticsearch version N/A

[ezimuel]

The issue is that for some endpoint we used GET instead of POST also if the body was not empty. I fixed this and released with 5.5.0.
I'm going to release also 6.5.1 and 6.7.2. The 7.0 branch should not be affected by the issue, since I generated the code from the Elasticsearch API specifications.