Using the infra that we now have in place, we can convert the low-level REST client docs so that they extract code snippets from real Java classes. This way we make sure that all the snippets properly compile. Compared to the high level REST client docs, in this case we don't run the tests themselves, as that would require depending on test-framework which requires java 8 while the low-level REST client is compatible with java 7. I think that compiling snippets is enough for now.
This commit converts the low level client and high level client chapters into two parts, which allows each high level client supported api to be on a separate page and show up in the index on the right.
The REST Client is split into 2 parts:
* Low level
* High level
The High level client has a main common section and the document delete API documentation as a start.
This adds the necessary `AuthCache` needed to support preemptive authorization. By adding every host to the cache, the automatically added `RequestAuthCache` interceptor will add credentials on the first pass rather than waiting to do it after _each_ anonymous request is rejected (thus always sending everything twice when basic auth is required).
All the language clients support a special ignore parameter that doesn't get passed to elasticsearch with the request, but used to indicate which error code should not lead to an exception if returned for a specific request.
Moving this to the low level REST client will allow the high level REST client to make use of it too, for instance so that it doesn't have to intercept ResponseExceptions when the get api returns a 404.
This change is the first towards providing the ability to store
sensitive settings in elasticsearch. It adds the
`elasticsearch-keystore` tool, which allows managing a java keystore.
The keystore is loaded upon node startup in Elasticsearch, and used by
the Setting infrastructure when a setting is configured as secure.
There are a lot of caveats to this PR. The most important is it only
provides the tool and setting infrastructure for secure strings. It does
not yet provide for keystore passwords, keypairs, certificates, or even
convert any existing string settings to secure string settings. Those
will all come in follow up PRs. But this PR was already too big, so this
at least gets a basic version of the infrastructure in.
The two main things to look at. The first is the `SecureSetting` class,
which extends `Setting`, but removes the assumption for the raw value of the
setting to be a string. SecureSetting provides, for now, a single
helper, `stringSetting()` to create a SecureSetting which will return a
SecureString (which is like String, but is closeable, so that the
underlying character array can be cleared). The second is the
`KeyStoreWrapper` class, which wraps the java `KeyStore` to provide a
simpler api (we do not need the entire keystore api) and also extend
the serialized format to add metadata needed for loading the keystore
with no assumptions about keystore type (so that we can change this in
the future) as well as whether the keystore has a password (so that we
can know whether prompting is necessary when we add support for keystore
passwords).
Changes the default socket and connection timeouts for the rest
client from 10 seconds to the more generous 30 seconds.
Defaults reindex-from-remote to those timeouts and make the
timeouts configurable like so:
```
POST _reindex
{
"source": {
"remote": {
"host": "http://otherhost:9200",
"socket_timeout": "1m",
"connect_timeout": "10s"
},
"index": "source",
"query": {
"match": {
"test": "data"
}
}
},
"dest": {
"index": "dest"
}
}
```
Closes#21707
* Rest client: don't reuse that same HttpAsyncResponseConsumer across multiple retries
Turns out that AbstractAsyncResponseConsumer from apache async http client is stateful and cannot be reused across multiple requests. The failover mechanism was mistakenly reusing that same instance, which can be provided by users, across retries in case nodes are down or return 5xx errors. The downside is that we have to change the signature of two public methods, as HttpAsyncResponseConsumer cannot be provided directly anymore, rather its factory needs to be provided which is going to be used to create one instance of the consumer per request attempt.
Up until now we tested our RestClient against multiple nodes only in a mock environment, where we don't really send http requests. In that scenario we can verify that retries etc. work properly but the interaction with the http client library in a real scenario is different and can catch other problems. With this commit we also add an integration test that sends requests to multiple hosts, and some of them may also get stopped meanwhile. The specific test for pathPrefix was also removed as pathPrefix is now randomly applied by default, hence implicitly tested. Moved also a small test method that checked the validity of the path argument to the unit test RestClientSingleHostTests.
Also increase default buffer limit to 100MB and make it required in default consumer
The default buffer limit used to be 10MB but that proved not to be high enough for scroll requests (see reindex from remote). With this commit we increase the limit to 100MB and make it a bit more visibile in the consumer factory.
[DOCS] add java REST client docs
Add some docs on how to get started with the Java REST client, some common configuration that may be needed and the sniffer component.