Add S3 custom 503 throttling detection

Author: RanVaknin

services/s3/src/main/java/software/amazon/awssdk/services/s3/internal/handlers/ExceptionTranslationInterceptor.java

@@ -75,6 +75,14 @@ public Throwable modifyException(Context.FailedExecution context, ExecutionAttri
                                             .message(message)
                                             .build();
             }
+        } else if (exception.statusCode() == 503 && "Slow Down".equals(errorDetails.sdkHttpResponse().statusText().orElse(null))) {
+            return S3Exception.builder()
+                              .awsErrorDetails(fillErrorDetails(errorDetails, "SlowDown", "Please reduce your request rate."))
+                              .statusCode(503)
+                              .requestId(requestId)
+                              .extendedRequestId(extendedRequestId)
+                              .message(message)
+                              .build();
         } else if (errorDetails.errorMessage() == null) {
             // Populate the error message using the HTTP response status text. Usually that's just the value from the
             // HTTP spec (e.g. "Forbidden"), but sometimes S3 throws some more useful things in there, like "Slow Down".

services/s3/src/test/java/software/amazon/awssdk/services/s3/internal/handlers/ExceptionTranslationInterceptorTest.java

@@ -98,6 +98,46 @@ public void otherRequest_shouldNotThrowException() {
         assertThat(interceptor.modifyException(failedExecution, new ExecutionAttributes())).isEqualTo(s3Exception);
     }
 
+    @Test
+    public void headObject503SlowDown_shouldBeThrottlingException() {
+        S3Exception s3Exception = create503ThrottlingException();
+        Context.FailedExecution failedExecution = getFailedExecution(s3Exception,
+                                                                     HeadObjectRequest.builder().build());
+        S3Exception modifiedException = (S3Exception) interceptor.modifyException(failedExecution, new ExecutionAttributes());
+        assertThat(modifiedException.awsErrorDetails().errorCode()).isEqualTo("SlowDown");
+        assertThat(modifiedException.isThrottlingException()).isTrue();
+    }
+
+    @Test
+    public void headBucket503SlowDown_shouldBeThrottlingException() {
+        S3Exception s3Exception = create503ThrottlingException();
+        Context.FailedExecution failedExecution = getFailedExecution(s3Exception,
+                                                                     HeadBucketRequest.builder().build());
+        S3Exception modifiedException = (S3Exception) interceptor.modifyException(failedExecution, new ExecutionAttributes());
+        assertThat(modifiedException.awsErrorDetails().errorCode()).isEqualTo("SlowDown");
+        assertThat(modifiedException.isThrottlingException()).isTrue();
+    }
+
+    @Test
+    public void headBucket503ServiceUnavailable_shouldNotBeThrottlingException() {
+        S3Exception s3Exception = create503NonThrottlingException();
+        Context.FailedExecution failedExecution = getFailedExecution(s3Exception,
+                                                                     HeadBucketRequest.builder().build());
+        S3Exception modifiedException = (S3Exception) interceptor.modifyException(failedExecution, new ExecutionAttributes());
+        assertThat(modifiedException.awsErrorDetails().errorCode()).isNull();
+        assertThat(modifiedException.isThrottlingException()).isFalse();
+    }
+
+    @Test
+    public void headObject503ServiceUnavailable_shouldNotBeThrottlingException() {
+        S3Exception s3Exception = create503NonThrottlingException();
+        Context.FailedExecution failedExecution = getFailedExecution(s3Exception,
+                                                                     HeadObjectRequest.builder().build());
+        S3Exception modifiedException = (S3Exception) interceptor.modifyException(failedExecution, new ExecutionAttributes());
+        assertThat(modifiedException.awsErrorDetails().errorCode()).isNull();
+        assertThat(modifiedException.isThrottlingException()).isFalse();
+    }
+
     private S3Exception create404S3Exception() {
         return (S3Exception) S3Exception.builder()
                                         .awsErrorDetails(AwsErrorDetails.builder()
@@ -118,4 +158,27 @@ private S3Exception create403S3Exception() {
                                         .statusCode(403)
                                         .build();
     }
+
+    private S3Exception create503ThrottlingException() {
+        return (S3Exception) S3Exception.builder()
+                                        .awsErrorDetails(AwsErrorDetails.builder()
+                                                                        .sdkHttpResponse(SdkHttpFullResponse.builder()
+                                                                                                            .statusText(
+                                                                                                                "Slow Down")
+                                                                                                            .build())
+                                                                        .build())
+                                        .statusCode(503)
+                                        .build();
+    }
+
+    private S3Exception create503NonThrottlingException() {
+        return (S3Exception) S3Exception.builder()
+                                        .awsErrorDetails(AwsErrorDetails.builder()
+                                                                        .sdkHttpResponse(SdkHttpFullResponse.builder()
+                                                                                            .statusText("Service Unavailable")
+                                                                                            .build())
+                                                                        .build())
+                                        .statusCode(503)
+                                        .build();
+    }
 }