TimeLimiter

Getting started with resilience4j-timelimiter

Create a TimeLimiterRegistry

Just like the CircuitBreaker module, this module provides an in-memory TimeLimiterRegistry which you can use to manage (create and retrieve) TimeLimiter instances.

Java

TimeLimiterRegistry timeLimiterRegistry = TimeLimiterRegistry.ofDefaults();

Create and configure TimeLimiter

You can provide a custom global TimeLimiterConfig. In order to create a custom global TimeLimiterConfig, you can use the TimeLimiterConfig builder. You can use the builder to configure:

• the timeout duration
• whether cancel should be called on the running future

Java

TimeLimiterConfig config = TimeLimiterConfig.custom()
   .cancelRunningFuture(true)
   .timeoutDuration(Duration.ofMillis(500))
   .build();

// Create a TimeLimiterRegistry with a custom global configuration
TimeLimiterRegistry timeLimiterRegistry = TimeLimiterRegistry.of(config);

// Get or create a TimeLimiter from the registry - 
// TimeLimiter will be backed by the default config
TimeLimiter timeLimiterWithDefaultConfig = registry.timeLimiter("name1");

// Get or create a TimeLimiter from the registry, 
// use a custom configuration when creating the TimeLimiter
TimeLimiterConfig config = TimeLimiterConfig.custom()
   .cancelRunningFuture(false)
   .timeoutDuration(Duration.ofMillis(1000))
   .build();

TimeLimiter timeLimiterWithCustomConfig = registry.timeLimiter("name2", config);

Decorate and execute a functional interface

TimeLimiter has higher order decorator functions to decorate a CompletionStage or Future in order to limit the execution time.

Java

// Given I have a helloWorldService.sayHelloWorld() method which takes too long
HelloWorldService helloWorldService = mock(HelloWorldService.class);

// Create a TimeLimiter
TimeLimiter timeLimiter = TimeLimiter.of(Duration.ofSeconds(1));
// The Scheduler is needed to schedule a timeout on a non-blocking CompletableFuture
ScheduledExecutorService scheduler = Executors.newScheduledThreadPool(3);

// The non-blocking variant with a CompletableFuture
CompletableFuture<String> result = timeLimiter.executeCompletionStage(
  scheduler, () -> CompletableFuture.supplyAsync(helloWorldService::sayHelloWorld)).toCompletableFuture();

// The blocking variant which is basically future.get(timeoutDuration, MILLISECONDS)
String result = timeLimiter.executeFutureSupplier(
  () -> CompletableFuture.supplyAsync(() -> helloWorldService::sayHelloWorld));