Merge pull request #165 from ajordens/propagate-429

Pass any 429's through without triggering any Hystrix events

gate-core/src/main/groovy/com/netflix/spinnaker/gate/retrofit/UpstreamBadRequest.java

@@ -18,6 +18,7 @@
 
 import com.netflix.hystrix.exception.HystrixBadRequestException;
 import retrofit.RetrofitError;
+import java.util.Collection;
 import static org.springframework.http.HttpStatus.INTERNAL_SERVER_ERROR;
 import static retrofit.RetrofitError.Kind.HTTP;
 
@@ -48,4 +49,12 @@ public static Exception classifyError(RetrofitError error) {
     }
   }
 
+  public static Exception classifyError(RetrofitError error, Collection<Integer> supportedHttpStatuses) {
+    if (error.getKind() == HTTP && supportedHttpStatuses.contains(error.getResponse().getStatus())) {
+      return new UpstreamBadRequest(error);
+    } else {
+      return error;
+    }
+  }
+
 }

gate-core/src/main/groovy/com/netflix/spinnaker/gate/services/commands/AbstractHystrixCommand.groovy

@@ -18,11 +18,15 @@ package com.netflix.spinnaker.gate.services.commands
 
 import com.netflix.hystrix.HystrixCommand
 import com.netflix.hystrix.HystrixCommandKey
+import com.netflix.spinnaker.gate.retrofit.UpstreamBadRequest
 import groovy.transform.CompileStatic
 import groovy.util.logging.Slf4j
+import org.springframework.http.HttpStatus
+import retrofit.RetrofitError
 
 import static HystrixFactory.createHystrixCommandPropertiesSetter
 import static HystrixFactory.toGroupKey
+import static retrofit.RetrofitError.Kind.HTTP
 
 @Slf4j
 @CompileStatic
@@ -49,7 +53,11 @@ abstract class AbstractHystrixCommand<T> extends HystrixCommand<T> {
 
   @Override
   protected T run() throws Exception {
-    return work()
+    try {
+      return work()
+    } catch (RetrofitError error) {
+      throw UpstreamBadRequest.classifyError(error, HttpStatus.values().findAll { it.is4xxClientError() }*.value() as Collection<Integer>)
+    }
   }
 
   protected T getFallback() {

gate-web/src/main/groovy/com/netflix/spinnaker/gate/config/GateWebConfig.groovy

@@ -16,16 +16,27 @@
 
 package com.netflix.spinnaker.gate.config
 
+import com.netflix.hystrix.exception.HystrixRuntimeException
 import com.netflix.spectator.api.Registry
+import com.netflix.spinnaker.gate.retrofit.UpstreamBadRequest
 import com.netflix.spinnaker.kork.web.interceptors.MetricsInterceptor
 import org.springframework.beans.factory.annotation.Autowired
 import org.springframework.context.annotation.Bean
 import org.springframework.context.annotation.ComponentScan
 import org.springframework.context.annotation.Configuration
+import org.springframework.http.HttpStatus
+import org.springframework.web.bind.annotation.ControllerAdvice
+import org.springframework.web.bind.annotation.ExceptionHandler
+import org.springframework.web.bind.annotation.ResponseBody
+import org.springframework.web.bind.annotation.ResponseStatus
 import org.springframework.web.filter.ShallowEtagHeaderFilter
 import org.springframework.web.servlet.config.annotation.InterceptorRegistry
 import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter
+import retrofit.RetrofitError
+
 import javax.servlet.Filter
+import javax.servlet.http.HttpServletRequest
+import javax.servlet.http.HttpServletResponse
 
 @Configuration
 @ComponentScan
@@ -46,4 +57,36 @@ public class GateWebConfig extends WebMvcConfigurerAdapter {
   Filter eTagFilter() {
     new ShallowEtagHeaderFilter()
   }
+
+  @Bean
+  UpstreamBadRequestExceptionHandler upstreamBadRequestExceptionHandler() {
+    return new UpstreamBadRequestExceptionHandler()
+  }
+
+  @ControllerAdvice
+  static class UpstreamBadRequestExceptionHandler {
+    @ResponseBody
+    @ExceptionHandler(UpstreamBadRequest)
+    public Map handleUpstreamBadRequest(
+      HttpServletRequest request,
+      HttpServletResponse response,
+      UpstreamBadRequest exception
+    ) {
+      response.setStatus(exception.status)
+
+      def failureCause = exception.cause
+      if (failureCause instanceof RetrofitError) {
+        failureCause = failureCause.cause ?: failureCause
+      }
+
+      return [
+        failureCause: failureCause.toString(),
+        error: HttpStatus.valueOf(exception.status).reasonPhrase,
+        message: exception.message,
+        status: exception.status,
+        url: exception.url,
+        timestamp: System.currentTimeMillis()
+      ]
+    }
+  }
 }