It requires the use of the spring-boot-starter-data-redis-reactive Spring Boot starter. It is a Spring Boot application with Spring Cloud stuff that can make it sit between clients and their requests and multiple services, where it offers features such as predicates for shaping. The RemoveJsonAttributesResponseBody GatewayFilter factory takes a collection of attribute names to search for, an optional last parameter from the list can be a boolean to remove the attributes just at root level (thats the default value if not present at the end of the parameter configuration, false) or recursively (true). Because Spring-Cloud-Gateway is a responsive architecture design based on WebFlux, traditional programming ideas are not suitable for the development of Reactor Stream in the process of migrating from Zuul. A gauge metric named spring.cloud.gateway.routes.count will be added, whose value is the number of RouteDefinitions. You can use it inside a regular Spring web handler as a method parameter. That is not a complete working sample, it is just some code. To add this functionality to the gateway, you need to add the TokenRelayGatewayFilterFactory like this: and it will (in addition to logging the user in and grabbing a token) The response is put in the ServerWebExchangeUtils.CLIENT_RESPONSE_ATTR exchange attribute for use in a . The Netty routing filter runs if the URL located in the ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR exchange attribute has a http or https scheme. Download ZIP. .metadata(RESPONSE_TIMEOUT_ATTR, 200) pass the authentication token downstream to the services (in this case import static org.springframework.cloud.gateway.support.RouteMetadataUtils.RESPONSE_TIMEOUT_ATTR; @Bean Then, by default, the metrics will be available as long as the property spring.cloud.gateway.metrics.enabled is set to true. To retrieve the GatewayFilter factories applied to routes, make a GET request to /actuator/gateway/routefilters. XForwardedRemoteAddressResolver::maxTrustedIndex takes an index that correlates to the number of trusted infrastructure running in front of Spring Cloud Gateway. Sign up for a free GitHub account to open an issue and contact its maintainers and the community. If the Gateway Handler Mapping determines that a request matches a route, it is sent to the Gateway Web Handler. If the fallback is called, the request is forwarded to the controller matched by the URI. To enable the Spring Cloud CircuitBreaker filter, you need to place spring-cloud-starter-circuitbreaker-reactor-resilience4j on the classpath. Cleanliness 4.4. Already on GitHub? By default, the RemoteAddr route predicate factory uses the remote address from the incoming request. The following listing configures a SetResponseHeader GatewayFilter: This GatewayFilter replaces (rather than adding) all headers with the given name. Spring Cloud Gateway offers two RouteDefinitionRepository implementations. With MVC, it also supports forwarding to a local handler through the forward() method. The RewritePath GatewayFilter factory takes a path regexp parameter and a replacement parameter. The following example configures a XForwardedRemoteAddr route predicate: This route matches if the X-Forwarded-For header contains, for example, 192.168.1.10. This is the full configuration of the shortcut configuration of the Cookie predicate shown above. You can configure these timeouts can be configured (defaults shown) as follows: Configuration for Spring Cloud Gateway is driven by a collection of RouteDefinitionLocator instances. The following example configures such a fallback: The following listing does the same thing in Java: This example forwards to the /inCaseofFailureUseThis URI when the circuit breaker fallback is called. If the response is already cached and a new request is performed with no-cache value in Cache-Control header, it returns a bodiless response with 304 (Not Modified). You can use the CacheRequestBody filter to cache the request body before sending it downstream and getting the body from exchange attribute. Generally, it will put the identity information into the request header and will not modify the content of the request and response. This may not match the actual client IP address if Spring Cloud Gateway sits behind a proxy layer. . Properties. URIs defined in routes without a port get default port values of 80 and 443 for the HTTP and HTTPS URIs, respectively. The input type is a Spring Framework ServerWebExchange. The following maxTrustedIndex values yield the following remote addresses: (invalid, IllegalArgumentException during initialization). If the URL has a lb scheme (such as lb://myservice), it uses the Spring Cloud ReactorLoadBalancer to resolve the name (myservice in this example) to an actual host and port and replaces the URI in the same attribute. To enable wiretap, set spring.cloud.gateway.httpserver.wiretap=true or spring.cloud.gateway.httpclient.wiretap=true for the HttpServer and HttpClient, respectively. The RewriteResponseHeader GatewayFilter factory takes name, regexp, and replacement parameters. Modifying the request body is a common requirement. For the external controller/handler scenario, headers can be added with exception details. The weights are calculated per group. For example, to reference a filter named Something in configuration files, the filter URI variables may be used in the value and are expanded at runtime. methods: The HTTP methods that should be retried, represented by using org.springframework.http.HttpMethod. This is the value of the Location header. You can read more about them in the. The following listing defines a set of default filters: The GlobalFilter interface has the same signature as GatewayFilter. The SaveSession GatewayFilter factory forces a WebSession::save operation before forwarding the call downstream. You can extend an abstract class called AbstractGatewayFilterFactory. This filter can be configured only by using the Java DSL. This predicates matches the Host header that matches the pattern. ALWAYS_STRIP: The version is always stripped, even if the original request path contains version. Sharing Routes between multiple Gateway instances, 17.1. The After route predicate factory takes one parameter, a datetime (which is a java ZonedDateTime). The RemoveRequestParameter GatewayFilter factory takes a name parameter. public RouteLocator customRouteLocator(RouteLocatorBuilder routeBuilder){ The following listing configures a RemoveRequestHeader GatewayFilter: This removes the X-Request-Foo header before it is sent downstream. }, 4. Currently, only forward: schemed URIs are supported. If youre using load-balanced routes, you need to explicitly define your. I got the root cause. If the URI has a scheme prefix, such as lb:ws://serviceid, the lb scheme is stripped from the URI and placed in the ServerWebExchangeUtils.GATEWAY_SCHEME_PREFIX_ATTR for use later in the filter chain. Various properties can be specified inside your application.properties file, inside your application.yml file, or as command line switches. When doing so, you need to make sure to include the default predicate and filter shown earlier, if you want to retain that functionality. A route is matched if the aggregate predicate is true. In the example below the call consumingServiceEndpoint/users/1 will be redirected to inCaseOfFailureUseThis/users/1. outcome: The outcome, as classified by HttpStatus.Series. Spring Cloud Gateway - read response body and set response headers Ask Question Asked 1 year, 11 months ago Modified 1 year, 11 months ago Viewed 675 times 0 I want to implement a GatewayFilter that reads the response body and out of this the response code is determined and should then be set afterwards. Spring Cloud Gateway comes with one non-default remote address resolver that is based off of the X-Forwarded-For header, XForwardedRemoteAddressResolver. if you intend to modify a JSON response body prior to returning to the client, the above gist will not work (i know because i tried). The following example configures a header route predicate: This route matches if the request has a header named X-Request-Id whose value matches the \d+ regular expression (that is, it has a value of one or more digits). The resulting response is similar to the following: The response contains the details of the GatewayFilter factories applied to any particular route. Since the request can be read only once, we need to cache the request body. The ForwardRoutingFilter looks for a URI in the exchange attribute ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR. By using the fluent Java API, you can use the and(), or(), and negate() operators on the Predicate class. The Host route predicate factory takes one parameter: a list of host name patterns. You can enable, disable, or configure policies to control how they modify APIcast. The RemoteAddr route predicate factory takes a list (min size 1) of sources, which are CIDR-notation (IPv4 or IPv6) strings, such as 192.168.0.1/16 (where 192.168.0.1 is an IP address and 16 is a subnet mask). The following listing configures a RewritePath GatewayFilter: For a request path of /red/blue, this sets the path to /blue before making the downstream request. The following listing configures a filter chain: To enable gateway metrics, add spring-boot-starter-actuator as a project dependency. The following example configures an AddRequestHeadersIfNotPresent GatewayFilter that uses a variable: The AddRequestParameter GatewayFilter Factory takes a name and value parameter. Temporary bursts can be allowed by setting burstCapacity higher than replenishRate. You can load-balance websockets by prefixing the URI with lb, such as lb:ws://serviceid. The default implementation of KeyResolver is the PrincipalNameKeyResolver, which retrieves the Principal from the ServerWebExchange and calls Principal.getName(). If matchTrailingSlash is set to false, then request path /red/1/ will not be matched. The url parameter should be a valid URL. However, you can customize this TrustManager by creating a bean of type GrpcSslConfigurer: This filter allows caching the response body and headers to follow these rules: It caches the response only for one of the following status codes: HTTP 200 (OK), HTTP 206 (Partial Content), or HTTP 301 (Moved Permanently). It is the name of the header to be removed. The following example shows how to do so: You can route gateway routes to both HTTP and HTTPS backends. To remove any kind of sensitive header, you should configure this filter for any routes for which you may want to do so. The following example configures a RemoteAddr route predicate: This route matches if the remote address of the request was, for example, 192.168.1.10. There are many caching cases on the network, but there are various Bug problems in the testing process. The most noteworthy thing here is: ServerHttpRequest or HttpMessage interface provides a method to get the request headers HttpHeaders getHeaders(); returns a read-only instance, specifically of type ReadOnlyHttpHeaders, mentioned here more than once I wrote this blog post using Spring Cloud Gateway version Greenwich.SR1. It also allows you to pass multi-value headers in the API response to implement things like sending multiple Set-Cookie headers. The new URI is placed in the ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR exchange attribute. The pattern is an Ant-style pattern with . To enable RouteDefinition metrics, add spring-boot-starter-actuator as a project dependency. For each factory there is a string representation of the corresponding object (for example, [[emailprotected] configClass = Object]). You can also define a rate limiter as a bean that implements the RateLimiter interface. In the next tutorial of Spring Cloud Gateway Example we will implement these theories and build an application with microservice architecture using Spring Cloud Gateway and demonstrate working examples on web filters to modify request and response body. .filters(f -> f.addRequestHeader("header1", "header-value-1")) If you include the starter, but you do not want the gateway to be enabled, set spring.cloud.gateway.enabled=false. The following listing configures a RemoveResponseHeader GatewayFilter: This will remove the X-Response-Foo header from the response before it is returned to the gateway client. Like in the case of global configuration, the properties belong to Spring Framework CorsConfiguration. Code Revisions 1 Stars 14 Forks 3. It is added to the ServerWebExchange as the ServerWebExchangeUtils.CIRCUITBREAKER_EXECUTION_EXCEPTION_ATTR attribute that can be used when handling the fallback within the gateway application. The XForwarded Headers Filter creates various X-Forwarded-* headers to send to the downstream service. If so, the same rules apply. So, if the downstream server responded with X-Request-Red:1234, it will be replaced with X-Request-Red:Blue, which is what the downstream service would receive. In future milestone releases, there will be some KeyResolver implementations. If the URL has a forward scheme (such as forward:///localendpoint), it uses the Spring DispatcherHandler to handle the request. httpMethod: The HTTP method used for the request. The Header route predicate factory takes two parameters, the header and a regexp (which is a Java regular expression). It supports basic downstream HTTP exchanges through methods that mirror the HTTP verbs. If the new named header already exists, its values are augmented with the new values. The following listing configures a redis-rate-limiter: Rate limits below 1 request/s are accomplished by setting replenishRate to the wanted number of requests, requestedTokens to the timespan in seconds, and burstCapacity to the product of replenishRate and requestedTokens. The RemoveResponseHeader GatewayFilter factory takes a name parameter. It accepts the first parameter to override the time to expire a cache entry (expressed in s for seconds, m for minutes, and h for hours) and a second parameter to set the maximum size of the cache to evict entries for this route (KB, MB, or GB). The Spring Cloud Gateway project is built on top of the popular Spring Boot 2 and Project Reactor, so it inherits its main treats: Low resource usage, thanks to its reactive nature Support for all goodies from the Spring Cloud ecosystem (discovery, configuration, etc.) The args key is a map of key value pairs to configure the predicate or filter. }) response-timeout must be specified in milliseconds. The following listing defines a rate limiter that uses the KeyResolver defined in the previous listing: The RewriteLocationResponseHeader GatewayFilter factory modifies the value of the Location response header, usually to get rid of backend-specific details. This is the number of tokens taken from the bucket for each request and defaults to 1. We've already covered its basic usage in earlier tutorials, so we won't get into those aspects here. The following examples show how to set up global pre- and post-filters, respectively: Spring Cloud Gateway provides a utility object called ProxyExchange. To be remotely accessible, the endpoint has to be enabled and exposed over HTTP or JMX in the application properties. The Path Route Predicate Factory takes two parameters: a list of Spring PathMatcher patterns and an optional flag called matchTrailingSlash (defaults to true). None of the prior documentation applies to what follows. It uses the Netty HttpClient to make the downstream proxy request. The following example configures a host route predicate: URI template variables (such as {sub}.myhost.org) are supported as well. The default is http|https|ftp|ftps. #{@myKeyResolver} is a SpEL expression that references a bean named myKeyResolver. You can add headers to the downstream response by using the header() methods on ProxyExchange. Spring Cloud Gateway 4.0.3 This project provides an API Gateway built on top of the Spring Ecosystem, including: Spring 6, Spring Boot 3 and Project Reactor. .metadata(CONNECT_TIMEOUT_ATTR, 200); First-class support is provided for sensitive headers (by default, cookie and authorization), which are not passed downstream, and for proxy (x-forwarded-*) headers. There should be no reason why a filter cannot modify a response header. The protocolsRegex parameter must be a valid regex String, against which the protocol name is matched. cloudflare tunnel home assistant 19 3407 . This filter also automatically calculates the. This predicate matches requests that happen after the specified datetime. If you want to customize the predicates or filters used by the DiscoveryClient routes, set spring.cloud.gateway.discovery.locator.predicates[x] and spring.cloud.gateway.discovery.locator.filters[y]. Configuring Predicates and Filters For, 15.4. Server. All of these predicates match on different attributes of the HTTP request. If the URL located in the ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR exchange attribute has a ws or wss scheme, the websocket routing filter runs. XForwardedRemoteAddressResolver has two static constructor methods, which take different approaches to security: XForwardedRemoteAddressResolver::trustAll returns a RemoteAddressResolver that always takes the first IP address found in the X-Forwarded-For header. Passing headers with Spring Cloud Feign. The global CORS configuration is a map of URL patterns to Spring Framework CorsConfiguration. Writing Custom Route Predicate Factories, 17.2. Once a request has been marked as routed, other routing filters will not route the request again, To change the default values, set the appropriate property in the spring.cloud.gateway.filter.secure-headers namespace. This filter adds a timer metric named spring.cloud.gateway.requests with the following tags: routeUri: The URI to which the API is routed. essentially skipping the filter. Creating of individual headers can be controlled by the following boolean properties (defaults to true): spring.cloud.gateway.x-forwarded.for-enabled, spring.cloud.gateway.x-forwarded.host-enabled, spring.cloud.gateway.x-forwarded.port-enabled, spring.cloud.gateway.x-forwarded.proto-enabled, spring.cloud.gateway.x-forwarded.prefix-enabled. per-route http timeouts configuration via configuration, per-route timeouts configuration using Java DSL, Example 73. The redis-rate-limiter.replenishRate property defines how many requests per second to allow (without any dropped requests). This vulnerability is known as HTTP Response Splitting. method: Method name in the service that handles the request. The following MVC example proxies a request to /test downstream to a remote server: The following example does the same thing with Webflux: Convenience methods on the ProxyExchange enable the handler method to discover and enhance the URI path of the incoming request. Displays the list of routes defined in the gateway. From the drop down, choose Mapping template and copy and paste the mapping template text below into the Template input box. This paper will introduce its usage in detail. Spring Cloud Gateway aims to provide a simple, yet effective way to route to APIs and provide cross cutting concerns to them such as: security, monitoring/metrics, and resiliency. The following example configures an RemoveJsonAttributesResponseBody GatewayFilter: This removes attributes "id" and "color" from the JSON content body at root level. It is defined by an ID, a destination URI, a collection of predicates, and a collection of filters. AddRequestHeadersIfNotPresent also supports URI variables used to match a path or host. All. Then the proxy request is made. Spring Cloud Zuul is one of the core components of Spring Cloud Netflix subproject. Spring Cloud Gateway. The reason the filters are divided by the dotted line is that filters can run logic both before and after the proxy request is sent. status codes that if returned will cause the circuit breaker to be tripped. response-timeout must be specified as a java.time.Duration. To create a route, make a POST request to /gateway/routes/{id_route_to_create} with a JSON body that specifies the fields of the route (see Retrieving Information about a Particular Route). Appending multiple headers can be controlled by the following boolean properties (defaults to true): spring.cloud.gateway.x-forwarded.for-append, spring.cloud.gateway.x-forwarded.host-append, spring.cloud.gateway.x-forwarded.port-append, spring.cloud.gateway.x-forwarded.proto-append, spring.cloud.gateway.x-forwarded.prefix-append. Easy to extend and/or customize using standard Spring patterns Fork 3. This allows more complex routing options, like forwarding sections of the original host or url path using PathPattern expression. The header is added to the response if configured with the following property: The StripPrefix GatewayFilter factory takes one parameter, parts. AddResponseHeader is aware of URI variables used to match a path or host. The RemoveHopByHop Headers Filter removes headers from forwarded requests. Creating and Deleting a Particular Route, 15.8. How does it work? In Puma (RubyGem) before 4.3.3 and 3.12.4, if an application using Puma allows untrusted input in an early-hints header, an attacker can use a carriage return character to end the header and inject malicious content, such as additional headers or an entirely new response body. The default filter is a rewrite path filter with the regex /serviceId/?(?. The following example configures an AddRequestHeader GatewayFilter that uses a variable: The AddRequestHeadersIfNotPresent GatewayFilter factory takes a collection of name and value pairs separated by colon. The following two examples are equivalent: When the request size is greater than the permissible limit, the RequestSize GatewayFilter factory can restrict a request from reaching the downstream service. These are basic guides to writing some custom components of the gateway. You must use $\ to mean $ because of the YAML specification. The PreserveHostHeader GatewayFilter factory has no parameters. Options. This predicate extracts the URI template variables (such as segment, defined in the preceding example) as a map of names and values and places it in the ServerWebExchange.getAttributes() with a key defined in ServerWebExchangeUtils.URI_TEMPLATE_VARIABLES_ATTRIBUTE. The DedupeResponseHeader filter also accepts an optional strategy parameter. Refresh the page, check Medium 's site status, or find something interesting to read. To clear the routes cache, make a POST request to /actuator/gateway/refresh. to your account, I am trying to modify a header of response in a post filter of gateway,the filter handle a cors problem which would filt websockt service ,the websockt service is a micro-service which must been decorated with cors configurationso a websockt request will get a response with multiple header like Access-Control-Allow-Origin, to solve this questioni must modify the response header of the key Access-Control-Allow-OriginHowever ,when i do this, a error occured, java.lang.UnsupportedOperationException: null at org.springframework.http.ReadOnlyHttpHeaders.set(ReadOnlyHttpHeaders.java:99) ~[spring-web-5.1.6.RELEASE.jar:5.1.6.RELEASE] at com.apigw.filter.CORSFilter.lambda$filter$0(CORSFilter.java:84) ~[classes/:na] at reactor.core.publisher.MonoRunnable.call(MonoRunnable.java:73) ~[reactor-core-3.2.8.RELEASE.jar:3.2.8.RELEASE]. Retries are performed after a backoff interval of firstBackoff * (factor ^ n), where n is the iteration. The following listing shows how to add local response cache GatewayFilter: The MapRequestHeader GatewayFilter factory takes fromHeader and toHeader parameters. import static org.springframework.cloud.gateway.support.RouteMetadataUtils.CONNECT_TIMEOUT_ATTR; Configuring Route Predicate Factories and Gateway Filter Factories, 5.10. Most examples below use the shortcut way. This interface and its usage are subject to change in future milestone releases. . Any otherway is there apart from blocking call? The first step is to create a ServerHttpResponseDecorator object and override the writeWith method. To enable this kind of repository, the following property has to set to true: spring.cloud.gateway.redis-route-definition-repository.enabled The following example configures an SetRequestHeader GatewayFilter that uses a variable: The SetResponseHeader GatewayFilter factory takes name and value parameters. HttpHeadersFilters are applied to the requests before sending them downstream, such as in the NettyRoutingFilter. In addition, through the spring.cloud.gateway.metrics.tags.path.enabled property (by default, false), you can activate an extra metric with the path tag: These metrics are then available to be scraped from /actuator/metrics/spring.cloud.gateway.requests and can be easily integrated with Prometheus to create a Grafana dashboard. The DedupeResponseHeader GatewayFilter factory takes a name parameter and an optional strategy parameter. Then look no further than Parkhotel Altmuehltal, a family-friendly hotel that brings the best of Gunzenhausen to your doorstep. Here is a link to someone asking about ordered filters that may provide more insight: #1341. In configuration, you can reference the bean by name using SpEL. CacheRequestBody then places it in the attributes available from ServerWebExchange.getAttributes(), with a key defined in ServerWebExchangeUtils.CACHED_REQUEST_BODY_ATTR. To retrieve information about a single route, make a GET request to /actuator/gateway/routes/{id} (for example, /actuator/gateway/routes/first_route). NOTE: This is not recommended for production. The following properties are available: To disable the default values set the spring.cloud.gateway.filter.secure-headers.disable property with comma-separated values.