Retry
Filter
The Retry
filter supports the following parameters:
-
retries
: The number of retries that should be attempted. -
methods
: The HTTP methods that should be retried, represented by usingorg.springframework.http.HttpMethod
. -
series
: The series of status codes to be retried, represented by usingorg.springframework.http.HttpStatus.Series
. -
exceptions
: A list of thrown exceptions that should be retried.
The following defaults are configured for Retry
filter, if enabled:
-
retries
: Three times -
series
: 5XX series -
methods
: GET method -
exceptions
:IOException
,TimeoutException
andRetryException
The following listing configures a Retry filter:
application.yml
spring:
cloud:
gateway:
mvc:
routes:
- id: retry_test
uri: http://localhost:8080/flakey
predicates:
- Host=*.retry.com
filters:
- name: Retry
args:
retries: 3
series: SERVER_ERROR
methods: GET,POST
GatewaySampleApplication.java
import static org.springframework.cloud.gateway.server.mvc.filter.RetryFilterFunctions.retry;
import static org.springframework.cloud.gateway.server.mvc.handler.GatewayRouterFunctions.route;
import static org.springframework.cloud.gateway.server.mvc.handler.HandlerFunctions.http;
import static org.springframework.cloud.gateway.server.mvc.predicate.GatewayRequestPredicates.host;
@Configuration
class RouteConfiguration {
@Bean
public RouterFunction<ServerResponse> gatewayRouterFunctionsAddReqHeader() {
return route("add_request_parameter_route")
.route(host("*.retry.com"), http("https://example.org"))
.filter(retry(config -> config.setRetries(3).setSeries(Set.of(HttpStatus.Series.SERVER_ERROR)).setMethods(Set.of(HttpMethod.GET, HttpMethod.POST))))
.build();
}
}
When using the retry filter with a forward: prefixed URL, the target endpoint should be written carefully so that, in case of an error, it does not do anything that could result in a response being sent to the client and committed.
For example, if the target endpoint is an annotated controller, the target controller method should not return ResponseEntity with an error status code.
Instead, it should throw an Exception or signal an error (for example, through a Mono.error(ex) return value), which the retry filter can be configured to handle by retrying.
|
When using the retry filter, it will retry all filters that come after it. Make sure the results of the filters following the retry filter are as expected when they are executed multiple times. |
A simplified "shortcut" notation can be added with a single status
and method
.
The following two examples are equivalent:
application.yml
spring:
cloud:
gateway:
routes:
- id: retry_route
uri: https://example.org
filters:
- name: Retry
args:
retries: 3
statuses: INTERNAL_SERVER_ERROR
methods: GET
- id: retryshortcut_route
uri: https://example.org
filters:
- Retry=3,INTERNAL_SERVER_ERROR,GET