test(showcase): add integration tests for resumable upload

java-showcase/gapic-showcase/src/test/java/com/google/showcase/v1beta1/it/ITResumableUpload.java

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+/*
+ * Copyright 2026 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
+ *
+ *      https://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.google.showcase.v1beta1.it;
+
+import static com.google.common.truth.Truth.assertThat;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import com.google.api.client.http.javanet.NetHttpTransport;
+import com.google.api.gax.core.NoCredentialsProvider;
+import com.google.api.gax.rpc.FailedPreconditionException;
+import com.google.api.gax.rpc.ResumableUploadFuture;
+import com.google.showcase.v1beta1.ResumableUploadServiceClient;
+import com.google.showcase.v1beta1.ResumableUploadServiceSettings;
+import com.google.showcase.v1beta1.UploadMediaRequest;
+import com.google.showcase.v1beta1.UploadMediaResponse;
+import com.google.showcase.v1beta1.it.util.TestClientInitializer;
+import io.grpc.ManagedChannelBuilder;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.concurrent.TimeUnit;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+/**
+ * Integration tests for generated {@link ResumableUploadServiceClient} against the Showcase server.
+ */
+class ITResumableUpload {
+
+  private static final int SHOWCASE_CHUNK_SIZE = 256 * 1024; // 256KB
+  private static ResumableUploadServiceClient client;
+
+  @BeforeAll
+  static void createClients() throws Exception {
+    ResumableUploadServiceSettings.Builder settingsBuilder =
+        ResumableUploadServiceSettings.newHttpJsonBuilder();
+    settingsBuilder
+        .setCredentialsProvider(NoCredentialsProvider.create())
+        .setTransportChannelProvider(
+            ResumableUploadServiceSettings.defaultHttpJsonTransportProviderBuilder()
+                .setHttpTransport(new NetHttpTransport.Builder().doNotValidateCertificate().build())
+                .setEndpoint(TestClientInitializer.DEFAULT_HTTPJSON_ENDPOINT)
+                .build());
+    settingsBuilder.uploadMediaSettings().setChunkSize(SHOWCASE_CHUNK_SIZE);
+    client = ResumableUploadServiceClient.create(settingsBuilder.build());
+  }
+
+  @AfterAll
+  static void destroyClients() throws InterruptedException {
+    if (client != null) {
+      client.close();
+      client.awaitTermination(TestClientInitializer.AWAIT_TERMINATION_SECONDS, TimeUnit.SECONDS);
+    }
+  }
+
+  @Test
+  void testGeneratedClient_uploadMedia_synchronousConvenienceMethod(@TempDir Path tempDir)
+      throws Exception {
+    Path file =
+        createTempFile(
+            tempDir,
+            "it-client-sync.txt",
+            "Hello from generated ResumableUploadServiceClient synchronous convenience method!"
+                .getBytes(StandardCharsets.UTF_8));
+    UploadMediaRequest request =
+        UploadMediaRequest.newBuilder().setName("it-client-sync.txt").build();
+
+    try (InputStream stream = new FileInputStream(file.toFile())) {
+      UploadMediaResponse response = client.uploadMedia(request, stream);
+      assertThat(response.getName()).isEqualTo("it-client-sync.txt");
+      assertThat(response.getSize()).isEqualTo(Files.size(file));
+    }
+  }
+
+  @Test
+  void testGeneratedClient_uploadMediaCallable_asynchronousFutureCall(@TempDir Path tempDir)
+      throws Exception {
+    Path file =
+        createTempFile(
+            tempDir,
+            "it-client-callable.txt",
+            "Hello from generated ResumableUploadServiceClient callable futureCall!"
+                .getBytes(StandardCharsets.UTF_8));
+    UploadMediaRequest request =
+        UploadMediaRequest.newBuilder().setName("it-client-callable.txt").build();
+
+    try (InputStream stream = new FileInputStream(file.toFile())) {
+      ResumableUploadFuture<UploadMediaResponse> future =
+          client.uploadMediaCallable().futureCall(request, stream);
+
+      UploadMediaResponse response = future.get(10, TimeUnit.SECONDS);
+      assertThat(future.isDone()).isTrue();
+      assertThat(future.isCancelled()).isFalse();
+      assertThat(future.getUploadSessionUrl()).isNotNull();
+      assertThat(response.getName()).isEqualTo("it-client-callable.txt");
+      assertThat(response.getSize()).isEqualTo(Files.size(file));
+    }
+  }
+
+  @Test
+  void testGeneratedClient_multiChunkUpload(@TempDir Path tempDir) throws Exception {
+    // 600KB payload = 2 full 256KB chunks + 1 partial 88KB chunk
+    int totalBytes = 600 * 1024;
+    Path file = createTempFile(tempDir, "it-client-multi-chunk.txt", totalBytes);
+    UploadMediaRequest request =
+        UploadMediaRequest.newBuilder().setName("it-client-multi-chunk.txt").build();
+
+    try (InputStream stream = new FileInputStream(file.toFile())) {
+      UploadMediaResponse response = client.uploadMedia(request, stream);
+      assertThat(response.getName()).isEqualTo("it-client-multi-chunk.txt");
+      assertThat(response.getSize()).isEqualTo(Files.size(file));
+    }
+  }
+
+  @Test
+  void testGeneratedClient_zeroByteUpload(@TempDir Path tempDir) throws Exception {
+    Path file = tempDir.resolve("it-client-zero-byte.txt");
+    Files.createFile(file);
+    UploadMediaRequest request =
+        UploadMediaRequest.newBuilder().setName("it-client-zero-byte.txt").build();
+
+    try (InputStream stream = new FileInputStream(file.toFile())) {
+      UploadMediaResponse response = client.uploadMedia(request, stream);
+      assertThat(response.getName()).isEqualTo("it-client-zero-byte.txt");
+      assertThat(response.getSize()).isEqualTo(0);
+    }
+  }
+
+  @Test
+  void testGeneratedClient_exactChunkBoundaryUpload(@TempDir Path tempDir) throws Exception {
+    // Exactly 2 full 256KB chunks (512KB total) -> triggers 0-byte finalize request
+    int totalBytes = 512 * 1024;
+    Path file = createTempFile(tempDir, "it-client-exact-chunks.txt", totalBytes);
+    UploadMediaRequest request =
+        UploadMediaRequest.newBuilder().setName("it-client-exact-chunks.txt").build();
+
+    try (InputStream stream = new FileInputStream(file.toFile())) {
+      UploadMediaResponse response = client.uploadMedia(request, stream);
+      assertThat(response.getName()).isEqualTo("it-client-exact-chunks.txt");
+      assertThat(response.getSize()).isEqualTo(Files.size(file));
+    }
+  }
+
+  @Test
+  void testChannelGuards_grpcChannelOnly_throwsFailedPreconditionException(@TempDir Path tempDir)
+      throws Exception {
+    ResumableUploadServiceSettings grpcSettings =
+        ResumableUploadServiceSettings.newBuilder()
+            .setCredentialsProvider(NoCredentialsProvider.create())
+            .setTransportChannelProvider(
+                ResumableUploadServiceSettings.defaultGrpcTransportProviderBuilder()
+                    .setChannelConfigurator(ManagedChannelBuilder::usePlaintext)
+                    .build())
+            .setEndpoint(TestClientInitializer.DEFAULT_GRPC_ENDPOINT)
+            .build();
+
+    Path file =
+        createTempFile(
+            tempDir, "guard-test.txt", "guard test data".getBytes(StandardCharsets.UTF_8));
+
+    try (ResumableUploadServiceClient grpcClient =
+        ResumableUploadServiceClient.create(grpcSettings)) {
+      UploadMediaRequest request =
+          UploadMediaRequest.newBuilder().setName("guard-test.txt").build();
+
+      try (InputStream stream1 = new FileInputStream(file.toFile())) {
+        // 1. Verify synchronous convenience call fails fast
+        FailedPreconditionException syncException =
+            assertThrows(
+                FailedPreconditionException.class, () -> grpcClient.uploadMedia(request, stream1));
+        assertThat(syncException.getMessage())
+            .contains("Resumable uploads execute over HTTP/REST and require credentials");
+      }
+
+      // 2. Verify callable getter fails fast
+      FailedPreconditionException callableException =
+          assertThrows(FailedPreconditionException.class, () -> grpcClient.uploadMediaCallable());
+      assertThat(callableException.getMessage())
+          .contains("Resumable uploads execute over HTTP/REST and require credentials");
+    }
+  }
+
+  private static Path createTempFile(Path dir, String fileName, byte[] data) throws IOException {
+    Path path = dir.resolve(fileName);
+    Files.write(path, data);
+    return path;
+  }
+
+  private static Path createTempFile(Path dir, String fileName, int size) throws IOException {
+    byte[] data = new byte[size];
+    for (int i = 0; i < size; i++) {
+      data[i] = (byte) (i % 256);
+    }
+    return createTempFile(dir, fileName, data);
+  }
+}