googleapis
diff --git a/google-cloud-storage/clirr-ignored-differences.xml b/google-cloud-storage/clirr-ignored-differences.xml
@@ -21,6 +21,16 @@
         <method>com.google.cloud.storage.BucketInfo$Builder deleteLifecycleRules()</method>
         <differenceType>7013</differenceType>
     </difference>
+    <difference>
+        <differenceType>7012</differenceType>
+        <className>com/google/cloud/storage/Storage</className>
+        <method>void abort(com.google.cloud.WriteChannel)</method>
+    </difference>
+    <difference>
+        <differenceType>7012</differenceType>
+        <className>com/google/cloud/storage/spi/v1/StorageRpc</className>
+        <method>void abort(java.lang.String)</method>
+    </difference>
     <difference>
         <className>com/google/cloud/storage/BucketInfo$Builder</className>
         <method>com.google.cloud.storage.BucketInfo$Builder setUpdateTime(java.lang.Long)</method>

diff --git a/google-cloud-storage/src/main/java/com/google/cloud/storage/BlobWriteChannel.java b/google-cloud-storage/src/main/java/com/google/cloud/storage/BlobWriteChannel.java
@@ -78,6 +78,24 @@ public void run() {
     }
   }
 
+  void cancelUpload() {
+    try {
+      runWithRetries(
+          callable(
+              new Runnable() {
+                @Override
+                public void run() {
+                  getOptions().getStorageRpcV1().abort(getUploadId());
+                }
+              }),
+          getOptions().getRetrySettings(),
+          StorageImpl.EXCEPTION_HANDLER,
+          getOptions().getClock());
+    } catch (RetryHelper.RetryHelperException e) {
+      throw StorageException.translateAndThrow(e);
+    }
+  }
+
   protected StateImpl.Builder stateBuilder() {
     return StateImpl.builder(getOptions(), getEntity(), getUploadId());
   }

diff --git a/google-cloud-storage/src/main/java/com/google/cloud/storage/Storage.java b/google-cloud-storage/src/main/java/com/google/cloud/storage/Storage.java
@@ -2692,6 +2692,17 @@ Blob createFrom(
    */
   WriteChannel writer(URL signedURL);
 
+  /**
+   * Aborts resumeable upload. Further attempts to write to or close the channel will result in
+   * {@code StorageException} with the code {@code 499}.
+   *
+   * @param channel an instance crated either by {@link #writer(BlobInfo, BlobWriteOption...)} or by
+   *     {@link #writer(URL)} method.
+   * @throws IllegalArgumentException if inappropriate channel is given
+   * @throws StorageException upon failure
+   */
+  void abort(WriteChannel channel);
+
   /**
    * Generates a signed URL for a blob. If you have a blob that you want to allow access to for a
    * fixed amount of time, you can use this method to generate a URL that is only valid within a

diff --git a/google-cloud-storage/src/main/java/com/google/cloud/storage/StorageImpl.java b/google-cloud-storage/src/main/java/com/google/cloud/storage/StorageImpl.java
@@ -696,6 +696,15 @@ public BlobWriteChannel writer(URL signedURL) {
     return new BlobWriteChannel(getOptions(), signedURL);
   }
 
+  @Override
+  public void abort(WriteChannel channel) {
+    if (!(channel instanceof BlobWriteChannel)) {
+      throw new IllegalArgumentException("channel is not created by Storage");
+    }
+    BlobWriteChannel blobWriteChannel = (BlobWriteChannel) channel;
+    blobWriteChannel.cancelUpload();
+  }
+
   private BlobWriteChannel writer(BlobInfo blobInfo, BlobTargetOption... options) {
     final Map<StorageRpc.Option, ?> optionsMap = optionMap(blobInfo, options);
     return new BlobWriteChannel(getOptions(), blobInfo, optionsMap);

diff --git a/google-cloud-storage/src/main/java/com/google/cloud/storage/spi/v1/HttpStorageRpc.java b/google-cloud-storage/src/main/java/com/google/cloud/storage/spi/v1/HttpStorageRpc.java
@@ -881,6 +881,48 @@ public String open(StorageObject object, Map<Option, ?> options) {
     }
   }
 
+  @Override
+  public void abort(String uploadId) {
+    Span span = startSpan(HttpStorageRpcSpans.SPAN_NAME_ABORT);
+    Scope scope = tracer.withSpan(span);
+    try {
+      GenericUrl url = new GenericUrl(uploadId);
+      HttpRequest httpRequest = storage.getRequestFactory().buildDeleteRequest(url);
+      int code;
+      String message;
+      IOException exception = null;
+      HttpResponse response = null;
+      try {
+        response = httpRequest.execute();
+        code = response.getStatusCode();
+        message = response.getStatusMessage();
+      } catch (HttpResponseException ex) {
+        exception = ex;
+        code = ex.getStatusCode();
+        message = ex.getStatusMessage();
+      } finally {
+        if (response != null) {
+          response.disconnect();
+        }
+      }
+      if (code != 499) {
+        if (exception != null) {
+          throw exception;
+        }
+        GoogleJsonError error = new GoogleJsonError();
+        error.setCode(code);
+        error.setMessage(message);
+        throw translate(error);
+      }
+    } catch (IOException ex) {
+      span.setStatus(Status.UNKNOWN.withDescription(ex.getMessage()));
+      throw translate(ex);
+    } finally {
+      scope.close();
+      span.end(HttpStorageRpcSpans.END_SPAN_OPTIONS);
+    }
+  }
+
   @Override
   public String open(String signedURL) {
     Span span = startSpan(HttpStorageRpcSpans.SPAN_NAME_OPEN);

diff --git a/google-cloud-storage/src/main/java/com/google/cloud/storage/spi/v1/HttpStorageRpcSpans.java b/google-cloud-storage/src/main/java/com/google/cloud/storage/spi/v1/HttpStorageRpcSpans.java
@@ -44,6 +44,7 @@ class HttpStorageRpcSpans {
   static final String SPAN_NAME_OPEN_REWRITE = getTraceSpanName("openRewrite(RewriteRequest)");
   static final String SPAN_NAME_CONTINUE_REWRITE =
       getTraceSpanName("continueRewrite(RewriteResponse)");
+  static final String SPAN_NAME_ABORT = getTraceSpanName("abort(String)");
   static final String SPAN_NAME_GET_BUCKET_ACL = getTraceSpanName("getAcl(String,String,Map)");
   static final String SPAN_NAME_DELETE_BUCKET_ACL =
       getTraceSpanName("deleteAcl(String,String,Map)");

diff --git a/google-cloud-storage/src/main/java/com/google/cloud/storage/spi/v1/StorageRpc.java b/google-cloud-storage/src/main/java/com/google/cloud/storage/spi/v1/StorageRpc.java
@@ -356,6 +356,13 @@ StorageObject writeWithResponse(
    */
   RewriteResponse openRewrite(RewriteRequest rewriteRequest);
 
+  /**
+   * Aborts the given resumable upload.
+   *
+   * @throws StorageException upon failure
+   */
+  void abort(String uploadId);
+
   /**
    * Continues rewriting on an already open rewrite channel.
    *

diff --git a/google-cloud-storage/src/main/java/com/google/cloud/storage/testing/StorageRpcTestBase.java b/google-cloud-storage/src/main/java/com/google/cloud/storage/testing/StorageRpcTestBase.java
@@ -155,6 +155,11 @@ public RewriteResponse openRewrite(RewriteRequest rewriteRequest) {
     throw new UnsupportedOperationException("Not implemented yet");
   }
 
+  @Override
+  public void abort(String uploadId) {
+    throw new UnsupportedOperationException("Not implemented yet");
+  }
+
   @Override
   public RewriteResponse continueRewrite(RewriteResponse previousResponse) {
     throw new UnsupportedOperationException("Not implemented yet");

diff --git a/google-cloud-storage/src/test/java/com/google/cloud/storage/StorageImplMockitoTest.java b/google-cloud-storage/src/test/java/com/google/cloud/storage/StorageImplMockitoTest.java
@@ -28,6 +28,7 @@
 
 import com.google.api.core.ApiClock;
 import com.google.api.services.storage.model.StorageObject;
+import com.google.cloud.BaseWriteChannel;
 import com.google.cloud.Identity;
 import com.google.cloud.Policy;
 import com.google.cloud.ReadChannel;
@@ -57,6 +58,7 @@
 import java.security.spec.X509EncodedKeySpec;
 import java.util.Arrays;
 import java.util.Map;
+import java.util.concurrent.atomic.AtomicBoolean;
 import javax.crypto.spec.SecretKeySpec;
 import org.junit.Before;
 import org.junit.BeforeClass;
@@ -1312,4 +1314,40 @@ public void testWriterFailure() {
       assertSame(STORAGE_FAILURE, e.getCause());
     }
   }
+
+  @Test
+  public void testAbort() {
+    final AtomicBoolean isAborted = new AtomicBoolean(false);
+    WriteChannel writer =
+        new BlobWriteChannel(options, "http://example.com") {
+          @Override
+          void cancelUpload() {
+            isAborted.set(true);
+          }
+        };
+    new StorageImpl(options).abort(writer);
+    assertTrue(isAborted.get());
+  }
+
+  @Test
+  public void testAbortNegative() {
+    WriteChannel writer =
+        new BaseWriteChannel(null, null, null) {
+          @Override
+          protected void flushBuffer(int i, boolean b) {
+            throw new IllegalStateException();
+          }
+
+          @Override
+          protected BaseState.Builder stateBuilder() {
+            throw new IllegalStateException();
+          }
+        };
+
+    try {
+      new StorageImpl(options).abort(writer);
+    } catch (IllegalArgumentException e) {
+      assertEquals("channel is not created by Storage", e.getMessage());
+    }
+  }
 }
diff --git a/google-cloud-storage/src/test/java/com/google/cloud/storage/it/ITStorageTest.java b/google-cloud-storage/src/test/java/com/google/cloud/storage/it/ITStorageTest.java
@@ -3490,6 +3490,31 @@ public void testAutoContentTypeWriter() throws IOException {
     testAutoContentType("writer");
   }
 
+  @Test
+  public void testAbort() throws IOException {
+    BlobId blobId = BlobId.of(BUCKET, "abortedObject");
+    int chunkSize = 256 * 1024;
+    WriteChannel writer = storage.writer(BlobInfo.newBuilder(blobId).build());
+    writer.setChunkSize(chunkSize);
+    writer.write(ByteBuffer.wrap(BLOB_BYTE_CONTENT));
+    storage.abort(writer);
+    try {
+      writer.write(ByteBuffer.wrap(new byte[chunkSize]));
+      fail();
+    } catch (StorageException e) {
+      assertEquals(499, e.getCode());
+      assertTrue(e.getMessage().startsWith("499 Client Closed Request"));
+    }
+    try {
+      writer.close();
+      fail();
+    } catch (StorageException e) {
+      assertEquals(499, e.getCode());
+      assertTrue(e.getMessage().startsWith("499 Client Closed Request"));
+    }
+    assertNull(storage.get(blobId));
+  }
+
   @Test
   public void testRemoveBucketCORS() throws ExecutionException, InterruptedException {
     String bucketName = RemoteStorageHelper.generateBucketName();