feat: Error Details Improvements - GRPC (#1634)

Fixes: #1635 
Key design notes:
1. All `ApiException` created for GRPC clients will go through `GrpcApiExceptionFactory` and the cause of `ApiException` already has all the info we need, hence the majority of the logic is in `GrpcApiExceptionFactory`.
2. Promoted all the fields of `ErrorInfo` to top level of `ApiException`, accessible through getters directly.
3. Encapsulated all the raw error messages from server to `ErrorDetails`. The unpacked error messages are accessible through getters.
4. If error messages from server are corrupted and unable to unpack, a `ProtocolBufferParsingException` will be thrown.

gax-grpc/src/main/java/com/google/api/gax/grpc/GrpcApiExceptionFactory.java

@@ -31,20 +31,26 @@
 
 import com.google.api.gax.rpc.ApiException;
 import com.google.api.gax.rpc.ApiExceptionFactory;
+import com.google.api.gax.rpc.ErrorDetails;
 import com.google.api.gax.rpc.StatusCode.Code;
+import com.google.common.annotations.VisibleForTesting;
 import com.google.common.collect.ImmutableSet;
+import com.google.protobuf.InvalidProtocolBufferException;
+import io.grpc.Metadata;
 import io.grpc.Status;
 import io.grpc.StatusException;
 import io.grpc.StatusRuntimeException;
 import java.util.Set;
 
 /**
  * Core logic for transforming GRPC exceptions into {@link ApiException}s. This logic is shared
- * amongst all of the call types.
+ * amongst all the call types.
  *
  * <p>Package-private for internal use.
  */
 class GrpcApiExceptionFactory {
+
+  @VisibleForTesting static final String ERROR_DETAIL_KEY = "grpc-status-details-bin";
   private final ImmutableSet<Code> retryableCodes;
 
   GrpcApiExceptionFactory(Set<Code> retryCodes) {
@@ -54,10 +60,10 @@ class GrpcApiExceptionFactory {
   ApiException create(Throwable throwable) {
     if (throwable instanceof StatusException) {
       StatusException e = (StatusException) throwable;
-      return create(throwable, e.getStatus().getCode());
+      return create(throwable, e.getStatus().getCode(), e.getTrailers());
     } else if (throwable instanceof StatusRuntimeException) {
       StatusRuntimeException e = (StatusRuntimeException) throwable;
-      return create(throwable, e.getStatus().getCode());
+      return create(throwable, e.getStatus().getCode(), e.getTrailers());
     } else if (throwable instanceof ApiException) {
       return (ApiException) throwable;
     } else {
@@ -67,8 +73,29 @@ ApiException create(Throwable throwable) {
     }
   }
 
-  private ApiException create(Throwable throwable, Status.Code statusCode) {
+  private ApiException create(Throwable throwable, Status.Code statusCode, Metadata metadata) {
     boolean canRetry = retryableCodes.contains(GrpcStatusCode.grpcCodeToStatusCode(statusCode));
-    return ApiExceptionFactory.createException(throwable, GrpcStatusCode.of(statusCode), canRetry);
+    GrpcStatusCode grpcStatusCode = GrpcStatusCode.of(statusCode);
+
+    if (metadata == null) {
+      return ApiExceptionFactory.createException(throwable, grpcStatusCode, canRetry);
+    }
+
+    byte[] bytes = metadata.get(Metadata.Key.of(ERROR_DETAIL_KEY, Metadata.BINARY_BYTE_MARSHALLER));
+    if (bytes == null) {
+      return ApiExceptionFactory.createException(throwable, grpcStatusCode, canRetry);
+    }
+
+    com.google.rpc.Status status;
+    try {
+      status = com.google.rpc.Status.parseFrom(bytes);
+    } catch (InvalidProtocolBufferException e) {
+      return ApiExceptionFactory.createException(throwable, grpcStatusCode, canRetry);
+    }
+
+    ErrorDetails.Builder errorDetailsBuilder = ErrorDetails.builder();
+    errorDetailsBuilder.setRawErrorMessages(status.getDetailsList());
+    return ApiExceptionFactory.createException(
+        throwable, grpcStatusCode, canRetry, errorDetailsBuilder.build());
   }
 }

gax-grpc/src/test/java/com/google/api/gax/grpc/GrpcApiExceptionFactoryTest.java

@@ -0,0 +1,139 @@
+/*
+ * Copyright 2022 Google LLC
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google LLC nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package com.google.api.gax.grpc;
+
+import static com.google.api.gax.grpc.GrpcApiExceptionFactory.ERROR_DETAIL_KEY;
+
+import com.google.api.gax.rpc.ApiException;
+import com.google.api.gax.rpc.ErrorDetails;
+import com.google.common.collect.ImmutableList;
+import com.google.common.truth.Truth;
+import com.google.protobuf.Any;
+import com.google.protobuf.Duration;
+import com.google.rpc.ErrorInfo;
+import com.google.rpc.RetryInfo;
+import com.google.rpc.Status;
+import io.grpc.Metadata;
+import io.grpc.StatusException;
+import io.grpc.StatusRuntimeException;
+import java.util.Collections;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+@RunWith(JUnit4.class)
+public class GrpcApiExceptionFactoryTest {
+
+  private static final ErrorInfo ERROR_INFO =
+      ErrorInfo.newBuilder()
+          .setDomain("googleapis.com")
+          .setReason("SERVICE_DISABLED")
+          .putAllMetadata(Collections.emptyMap())
+          .build();
+
+  private static final RetryInfo RETRY_INFO =
+      RetryInfo.newBuilder().setRetryDelay(Duration.newBuilder().setSeconds(213).build()).build();
+
+  private static final ImmutableList<Any> RAW_ERROR_MESSAGES =
+      ImmutableList.of(Any.pack(ERROR_INFO), Any.pack(RETRY_INFO));
+
+  private static final ErrorDetails ERROR_DETAILS =
+      ErrorDetails.builder().setRawErrorMessages(RAW_ERROR_MESSAGES).build();
+
+  private static final io.grpc.Status GRPC_STATUS = io.grpc.Status.CANCELLED;
+
+  private GrpcApiExceptionFactory factory;
+
+  @Before
+  public void setUp() throws Exception {
+    factory = new GrpcApiExceptionFactory(Collections.emptySet());
+  }
+
+  @Test
+  public void create_shouldCreateApiExceptionWithErrorDetailsForStatusException() {
+    Metadata trailers = new Metadata();
+    Status status = Status.newBuilder().addAllDetails(RAW_ERROR_MESSAGES).build();
+    trailers.put(
+        Metadata.Key.of(ERROR_DETAIL_KEY, Metadata.BINARY_BYTE_MARSHALLER), status.toByteArray());
+    StatusException statusException = new StatusException(GRPC_STATUS, trailers);
+
+    ApiException actual = factory.create(statusException);
+
+    Truth.assertThat(actual.getErrorDetails()).isEqualTo(ERROR_DETAILS);
+  }
+
+  @Test
+  public void create_shouldCreateApiExceptionWithErrorDetailsForStatusRuntimeException() {
+    Metadata trailers = new Metadata();
+    Status status = Status.newBuilder().addAllDetails(RAW_ERROR_MESSAGES).build();
+    trailers.put(
+        Metadata.Key.of(ERROR_DETAIL_KEY, Metadata.BINARY_BYTE_MARSHALLER), status.toByteArray());
+    StatusRuntimeException statusException = new StatusRuntimeException(GRPC_STATUS, trailers);
+
+    ApiException actual = factory.create(statusException);
+
+    Truth.assertThat(actual.getErrorDetails()).isEqualTo(ERROR_DETAILS);
+  }
+
+  @Test
+  public void create_shouldCreateApiExceptionWithNoErrorDetailsIfMetadataIsNull() {
+    StatusRuntimeException statusException = new StatusRuntimeException(GRPC_STATUS, null);
+
+    ApiException actual = factory.create(statusException);
+
+    Truth.assertThat(actual.getErrorDetails()).isNull();
+  }
+
+  @Test
+  public void create_shouldCreateApiExceptionWithNoErrorDetailsIfMetadataDoesNotHaveErrorDetails() {
+    StatusRuntimeException statusException =
+        new StatusRuntimeException(GRPC_STATUS, new Metadata());
+
+    ApiException actual = factory.create(statusException);
+
+    Truth.assertThat(actual.getErrorDetails()).isNull();
+  }
+
+  @Test
+  public void create_shouldCreateApiExceptionWithNoErrorDetailsIfStatusIsMalformed() {
+    Metadata trailers = new Metadata();
+    Status status = Status.newBuilder().addDetails(Any.pack(ERROR_INFO)).build();
+    byte[] bytes = status.toByteArray();
+    // manually manipulate status bytes array
+    bytes[0] = 123;
+    trailers.put(Metadata.Key.of(ERROR_DETAIL_KEY, Metadata.BINARY_BYTE_MARSHALLER), bytes);
+    StatusRuntimeException statusException = new StatusRuntimeException(GRPC_STATUS, trailers);
+
+    ApiException actual = factory.create(statusException);
+
+    Truth.assertThat(actual.getErrorDetails()).isNull();
+  }
+}

gax/BUILD.bazel

@@ -9,6 +9,8 @@ _JAVA_COPTS = [
 
 _COMPILE_DEPS = [
     "@com_google_api_api_common//jar",
+    "@com_google_api_grpc_proto_google_common_protos//jar",
+    "@com_google_protobuf_java//jar",
     "@com_google_auth_google_auth_library_credentials//jar",
     "@com_google_auth_google_auth_library_oauth2_http//jar",
     "@com_google_auto_value_auto_value//jar",

gax/build.gradle

@@ -5,7 +5,8 @@ project.version = "2.14.0" // {x-version-update:gax:current}
 
 dependencies {
   api(libraries['maven.com_google_api_api_common'],
-    libraries['maven.com_google_auth_google_auth_library_credentials'],
+          libraries['maven.com_google_api_grpc_proto_google_common_protos'],
+          libraries['maven.com_google_auth_google_auth_library_credentials'],
     libraries['maven.org_threeten_threetenbp'])
 
   implementation(libraries['maven.com_google_auth_google_auth_library_oauth2_http'],

gax/src/main/java/com/google/api/gax/rpc/AbortedException.java

@@ -42,4 +42,9 @@ public AbortedException(
       String message, Throwable cause, StatusCode statusCode, boolean retryable) {
     super(message, cause, statusCode, retryable);
   }
+
+  public AbortedException(
+      Throwable cause, StatusCode statusCode, boolean retryable, ErrorDetails errorDetails) {
+    super(cause, statusCode, retryable, errorDetails);
+  }
 }

gax/src/main/java/com/google/api/gax/rpc/AlreadyExistsException.java

@@ -42,4 +42,9 @@ public AlreadyExistsException(
       String message, Throwable cause, StatusCode statusCode, boolean retryable) {
     super(message, cause, statusCode, retryable);
   }
+
+  public AlreadyExistsException(
+      Throwable cause, StatusCode statusCode, boolean retryable, ErrorDetails errorDetails) {
+    super(cause, statusCode, retryable, errorDetails);
+  }
 }

gax/src/main/java/com/google/api/gax/rpc/ApiException.java

@@ -30,24 +30,34 @@
 package com.google.api.gax.rpc;
 
 import com.google.common.base.Preconditions;
+import java.util.Map;
 
 /** Represents an exception thrown during an RPC call. */
 public class ApiException extends RuntimeException {
+
   private static final long serialVersionUID = -4375114339928877996L;
 
+  private final ErrorDetails errorDetails;
   private final StatusCode statusCode;
   private final boolean retryable;
 
   public ApiException(Throwable cause, StatusCode statusCode, boolean retryable) {
-    super(cause);
-    this.statusCode = Preconditions.checkNotNull(statusCode);
-    this.retryable = retryable;
+    this(cause, statusCode, retryable, null);
   }
 
   public ApiException(String message, Throwable cause, StatusCode statusCode, boolean retryable) {
     super(message, cause);
     this.statusCode = Preconditions.checkNotNull(statusCode);
     this.retryable = retryable;
+    this.errorDetails = null;
+  }
+
+  public ApiException(
+      Throwable cause, StatusCode statusCode, boolean retryable, ErrorDetails errorDetails) {
+    super(cause);
+    this.statusCode = Preconditions.checkNotNull(statusCode);
+    this.retryable = retryable;
+    this.errorDetails = errorDetails;
   }
 
   /** Returns whether the failed request can be retried. */
@@ -59,4 +69,43 @@ public boolean isRetryable() {
   public StatusCode getStatusCode() {
     return statusCode;
   }
+
+  /**
+   * Returns the reason of the exception. This is a constant value that identifies the proximate
+   * cause of the error. e.g. SERVICE_DISABLED
+   */
+  public String getReason() {
+    if (isErrorInfoEmpty()) {
+      return null;
+    }
+    return errorDetails.getErrorInfo().getReason();
+  }
+
+  /**
+   * Returns the logical grouping to which the "reason" belongs. The error domain is typically the
+   * registered service name of the tool or product that generates the error. e.g. googleapis.com
+   */
+  public String getDomain() {
+    if (isErrorInfoEmpty()) {
+      return null;
+    }
+    return errorDetails.getErrorInfo().getDomain();
+  }
+
+  /** Returns additional structured details about this exception. */
+  public Map<String, String> getMetadata() {
+    if (isErrorInfoEmpty()) {
+      return null;
+    }
+    return errorDetails.getErrorInfo().getMetadataMap();
+  }
+
+  /** Returns all standard error messages that server sends. */
+  public ErrorDetails getErrorDetails() {
+    return errorDetails;
+  }
+
+  private boolean isErrorInfoEmpty() {
+    return errorDetails == null || errorDetails.getErrorInfo() == null;
+  }
 }