The callback replaces the ability to fully replace the http client instance. By doing that, one used to lose any default that the RestClient had set for the underlying http client. Given that you'd usually override one or two things only, like a couple of timeout values, the ssl factory or the default credentials providers, it is not uder friendly if by doing that users end up replacing the whole http client instance and lose any default set by us.
Users wanting to send a request by providing only its method and endpoint, effectively the only two required arguments, shouldn't need to pass in an empty map and a null entity for the body. While at it we can also add a variant to send requests by specifying only method, endpoint and params, but not body. Headers remain a vararg as last argument, so they can always optionally be provided.
Closes#19312
The assumption is HostsSniffer is that all of the arguments have been properly provided and validated through HostsSniffer.Builder, except they weren't, as the scheme didn't have a default value and when not set would cause NPEs down the road. Improved tests to catch this also.
Some Rest tests use the Sun HTTP server which has lingering threads after shutdown. Similar to ESTestCase, this adds an
option to wait 5 seconds for these threads to terminate.
:client ---------> :client:rest
:client-sniffer -> :client:sniffer
:client-test ----> :client:test
This lines the client up with how we do things like modules and
plugins.
The lucene-test dependency caused issues with IDEs as they would always load the lucene 5 jar although they shouldn't have, which caused jarhell in es core tests.
If we depend directly on randomized runner we don't have this problem. It is luckily still compatible with java 1.7. This requires though adding a thin module that includes the base test class which can be shared between client and client-sniffer.
Projects that don't depend on elasticsearch-test fail otherwise because org.elasticsearch.test.EsIntegTestCase (default integ test class) is not in the classpath. They should provide their onw integ test base class, but having integration tests should not be mandatory. One can simply set skipIntegTestsInDisguise to true to prevent loading of integ test class.