//// This file is included by every high level rest client API documentation page so we don't have to copy and paste the same asciidoc over and over again. We *do* have to copy and paste the same Java tests over and over again. For now this is intentional because it forces us to *write* and execute the tests which, while a bit ceremonial, does force us to cover these calls in *some* test. //// [id="{upid}-{api}-sync"] ==== Synchronous execution When executing a +{request}+ in the following manner, the client waits for the +{response}+ to be returned before continuing with code execution: ["source","java",subs="attributes,callouts,macros"] -------------------------------------------------- include-tagged::{doc-tests-file}[{api}-execute] -------------------------------------------------- Synchronous calls may throw an `IOException` in case of either failing to parse the REST response in the high-level REST client, the request times out or similar cases where there is no response coming back from the server. In cases where the server returns a `4xx` or `5xx` error code, the high-level client tries to parse the response body error details instead and then throws a generic `ElasticsearchException` and adds the original `ResponseException` as a suppressed exception to it. [id="{upid}-{api}-async"] ==== Asynchronous execution Executing a +{request}+ can also be done in an asynchronous fashion so that the client can return directly. Users need to specify how the response or potential failures will be handled by passing the request and a listener to the asynchronous {api} method: ["source","java",subs="attributes,callouts,macros"] -------------------------------------------------- include-tagged::{doc-tests-file}[{api}-execute-async] -------------------------------------------------- <1> The +{request}+ to execute and the `ActionListener` to use when the execution completes The asynchronous method does not block and returns immediately. Once it is completed the `ActionListener` is called back using the `onResponse` method if the execution successfully completed or using the `onFailure` method if it failed. Failure scenarios and expected exceptions are the same as in the synchronous execution case. A typical listener for +{api}+ looks like: ["source","java",subs="attributes,callouts,macros"] -------------------------------------------------- include-tagged::{doc-tests-file}[{api}-execute-listener] -------------------------------------------------- <1> Called when the execution is successfully completed. <2> Called when the whole +{request}+ fails.