Simplify Sniffer initialization and automatically create the default HostsSniffer
Take Sniffer.Builder out to its own top level class. Remove HostsSniffer.Builder and let SnifferBuilder create the default HostsSniffer. This simplifies the Sniffer initialization as the HostsSniffer is not mandatory anymore. It can still be specified though in case the configuration needs to be changed or a different impl has to be used. Also make HostsSniffer an interface.
It can happen that the list of healthy hosts is empty, then we get one from the blacklist. but some other operation might have sneaked in and emptied the blacklist in the meantime, so we have to retry till we manage to get some host, either from the healthy list or from the blacklist.
Throw explicit IllegalStateException in unexpected situations, like where both response and exception are set, or when both are unset. Add unit test for SyncResponseListener.
We throw IOException, which is the exception that is going to be thrown in 99% of the cases. A more generic exception can happen, and if it is a runtime one we just let it bubble up as is, otherwise we wrap it into runtime one so that we don't require to catch Exception everywhere, which seems odd.
Also adjusted javadocs for all performRequest methods
We keep the default async client behaviour like in BasicAsyncResponseConsumer, but we lower the maximum size of the buffer from Integer.MAX_VALUE (2GB) to 10 MB. This way users will realize they are buffering big responses in heap hence they'll know they have to do something about it, either write their own response consumer or increase the buffer size limit by providing their manually creeted instance of HeapBufferedAsyncResponseConsumer (constructor accept a bufferLimit int argument).
Also delayed call to HttpAsyncClient#start so that if something goes wrong while creating the RestClient, the http client threads don't linger. In fact, if the constructor fails it is not possible to call close against the RestClient.
HttpClientConfigCallback#customizeHttpClient now also returns the HttpClientBuilder so it can be completely replaced
RequestConfigCallback#customizeRequestConfig now also returns the HttpClientBuilder so it can be completely replaced
The new method accepts the usual parameters (method, endpoint, params, entity and headers) plus a response listener and an async response consumer. Shortcut methods are also added that don't require params, entity and the async response consumer optional.
There are a few relevant api changes as a consequence of the move to async client that affect sync methods:
- Response doesn't implement Closeable anymore, responses don't need to be closed
- performRequest throws Exception rather than just IOException, as that is the the exception that we get from the FutureCallback#failed method in the async http client
- ssl configuration is a bit simpler, one only needs to call setSSLStrategy from a custom HttpClientConfigCallback, that doesn't end up overridng any other default around connection pooling (it used to happen with the sync client and make ssl configuration more complex)
Relates to #19055
The `client/transport` project adds a new jar build project that
pulls in all dependencies and configures all required modules.
Preinstalled modules are:
* transport-netty
* lang-mustache
* reindex
* percolator
The `TransportClient` classes are still in core
while `TransportClient.Builder` has only a protected construcutor
such that users are redirected to use the new `TransportClientBuilder`
from the new jar.
Closes#19412
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.
Luca Cavanna
Daniel Mitterdorfer
Jason Tedor
javanna
Simon Willnauer
Tanguy Leroux
Yannick Welsch
Nik Everett