samples: vision: move samples out of branch and add clarifying comments (#2297)

Author: nnegrey

vision/snippets/src/main/java/com/example/vision/AsyncBatchAnnotateImages.java

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+/*
+ * Copyright 2020 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example.vision;
+
+// [START vision_async_batch_annotate_images]
+import com.google.cloud.vision.v1.AnnotateImageRequest;
+import com.google.cloud.vision.v1.AsyncBatchAnnotateImagesRequest;
+import com.google.cloud.vision.v1.AsyncBatchAnnotateImagesResponse;
+import com.google.cloud.vision.v1.Feature;
+import com.google.cloud.vision.v1.GcsDestination;
+import com.google.cloud.vision.v1.Image;
+import com.google.cloud.vision.v1.ImageAnnotatorClient;
+import com.google.cloud.vision.v1.ImageSource;
+import com.google.cloud.vision.v1.OutputConfig;
+
+import java.io.IOException;
+import java.util.concurrent.ExecutionException;
+
+public class AsyncBatchAnnotateImages {
+
+  public static void asyncBatchAnnotateImages()
+      throws InterruptedException, ExecutionException, IOException {
+    String inputImageUri = "gs://cloud-samples-data/vision/label/wakeupcat.jpg";
+    String outputUri = "gs://YOUR_BUCKET_ID/path/to/save/results/";
+    asyncBatchAnnotateImages(inputImageUri, outputUri);
+  }
+
+  public static void asyncBatchAnnotateImages(String inputImageUri, String outputUri)
+      throws IOException, ExecutionException, InterruptedException {
+    // Initialize client that will be used to send requests. This client only needs to be created
+    // once, and can be reused for multiple requests. After completing all of your requests, call
+    // the "close" method on the client to safely clean up any remaining background resources.
+    try (ImageAnnotatorClient imageAnnotatorClient = ImageAnnotatorClient.create()) {
+
+      // You can send multiple images to be annotated, this sample demonstrates how to do this with
+      // one image. If you want to use multiple images, you have to create a `AnnotateImageRequest`
+      // object for each image that you want annotated.
+      // First specify where the vision api can find the image
+      ImageSource source = ImageSource.newBuilder().setImageUri(inputImageUri).build();
+      Image image = Image.newBuilder().setSource(source).build();
+
+      // Set the type of annotation you want to perform on the image
+      // https://cloud.google.com/vision/docs/reference/rpc/google.cloud.vision.v1#google.cloud.vision.v1.Feature.Type
+      Feature feature = Feature.newBuilder().setType(Feature.Type.LABEL_DETECTION).build();
+
+      // Build the request object for that one image. Note: for additional images you have to create
+      // additional `AnnotateImageRequest` objects and store them in a list to be used below.
+      AnnotateImageRequest imageRequest =
+          AnnotateImageRequest.newBuilder().setImage(image).addFeatures(feature).build();
+
+      // Set where to store the results for the images that will be annotated.
+      GcsDestination gcsDestination = GcsDestination.newBuilder().setUri(outputUri).build();
+      OutputConfig outputConfig =
+          OutputConfig.newBuilder()
+              .setGcsDestination(gcsDestination)
+              .setBatchSize(2) // The max number of responses to output in each JSON file
+              .build();
+
+      // Add each `AnnotateImageRequest` object to the batch request and add the output config.
+      AsyncBatchAnnotateImagesRequest request =
+          AsyncBatchAnnotateImagesRequest.newBuilder()
+              .addRequests(imageRequest)
+              .setOutputConfig(outputConfig)
+              .build();
+
+      // Make the asynchronous batch request.
+      AsyncBatchAnnotateImagesResponse response =
+          imageAnnotatorClient.asyncBatchAnnotateImagesAsync(request).get();
+
+      // The output is written to GCS with the provided output_uri as prefix
+      String gcsOutputUri = response.getOutputConfig().getGcsDestination().getUri();
+      System.out.printf("Output written to GCS with prefix: %s\n", gcsOutputUri);
+    }
+  }
+}
+// [END vision_async_batch_annotate_images]

vision/snippets/src/test/java/com/example/vision/AsyncBatchAnnotateImagesTest.java

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+/*
+ * Copyright 2020 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example.vision;
+
+import static com.google.common.truth.Truth.assertThat;
+import static junit.framework.TestCase.assertNotNull;
+
+import com.google.api.gax.paging.Page;
+import com.google.cloud.storage.Blob;
+import com.google.cloud.storage.Storage;
+import com.google.cloud.storage.StorageOptions;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.PrintStream;
+import java.util.UUID;
+import java.util.concurrent.ExecutionException;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.BeforeClass;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+@RunWith(JUnit4.class)
+@SuppressWarnings("checkstyle:abbreviationaswordinname")
+public class AsyncBatchAnnotateImagesTest {
+  private static final String PROJECT_ID = System.getenv("GOOGLE_CLOUD_PROJECT");
+  private static final String INPUT_URI = "gs://cloud-samples-data/vision/label/wakeupcat.jpg";
+  private static final String PREFIX = String.format("vision/%s/", UUID.randomUUID().toString());
+  private static final String OUTPUT_URI = String.format("gs://%s/%s", PROJECT_ID, PREFIX);
+
+  private ByteArrayOutputStream bout;
+  private PrintStream out;
+
+  private static void requireEnvVar(String varName) {
+    assertNotNull(
+            System.getenv(varName),
+            "Environment variable '%s' is required to perform these tests.".format(varName));
+  }
+
+  @BeforeClass
+  public static void checkRequirements() {
+    requireEnvVar("GOOGLE_CLOUD_PROJECT");
+  }
+
+  @Before
+  public void setUp() {
+    bout = new ByteArrayOutputStream();
+    out = new PrintStream(bout);
+    System.setOut(out);
+  }
+
+  @After
+  public void tearDown() {
+    System.setOut(null);
+
+    Storage storage = StorageOptions.getDefaultInstance().getService();
+
+    Page<Blob> blobs = storage.list(PROJECT_ID, Storage.BlobListOption.currentDirectory(),
+            Storage.BlobListOption.prefix(PREFIX));
+    for (Blob blob : blobs.iterateAll()) {
+      blob.delete();
+    }
+  }
+
+  @Test
+  public void testSetEndpoint() throws IOException, ExecutionException, InterruptedException {
+    AsyncBatchAnnotateImages.asyncBatchAnnotateImages(INPUT_URI, OUTPUT_URI);
+    String got = bout.toString();
+    assertThat(got).contains("Output written to GCS with prefix");
+  }
+}