Add initial tests and utilities

Author: cindy-peng

google-cloud-datastore-utils/pom.xml

@@ -68,6 +68,23 @@
             <artifactId>jsr305</artifactId>
         </dependency>
         <!-- Test dependencies -->
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.google.truth</groupId>
+            <artifactId>truth</artifactId>
+            <version>1.4.2</version>
+            <scope>test</scope>
+            <exclusions>
+                <exclusion>
+                    <groupId>org.checkerframework</groupId>
+                    <artifactId>checker-qual</artifactId>
+                </exclusion>
+            </exclusions>
+        </dependency>
     </dependencies>
 
     <build>

google-cloud-datastore-utils/src/main/java/com/google/datastore/utils/testing/MockCredential.java

@@ -0,0 +1,36 @@
+/*
+ * Copyright 2022 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.google.datastore.utils.testing;
+
+import com.google.api.client.auth.oauth2.Credential;
+import com.google.api.client.http.HttpRequest;
+import java.io.IOException;
+
+/** Fake credential used for testing purpose. */
+public class MockCredential extends Credential {
+  public MockCredential() {
+    super(
+        new AccessMethod() {
+          @Override
+          public void intercept(HttpRequest request, String accessToken) throws IOException {}
+
+          @Override
+          public String getAccessTokenFromRequest(HttpRequest request) {
+            return "MockAccessToken";
+          }
+        });
+  }
+}

google-cloud-datastore-utils/src/main/java/com/google/datastore/utils/testing/MockDatastoreFactory.java

@@ -0,0 +1,132 @@
+/*
+ * Copyright 2022 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.google.datastore.utils.testing;
+
+import static com.google.common.base.Preconditions.checkState;
+
+import com.google.api.client.auth.oauth2.Credential;
+import com.google.api.client.http.*;
+import com.google.api.client.testing.http.MockHttpTransport;
+import com.google.api.client.testing.http.MockLowLevelHttpRequest;
+import com.google.api.client.testing.http.MockLowLevelHttpResponse;
+import com.google.api.client.testing.util.TestableByteArrayInputStream;
+import com.google.common.collect.Iterables;
+import com.google.datastore.utils.DatastoreFactory;
+import com.google.datastore.utils.DatastoreOptions;
+import com.google.protobuf.Message;
+import com.google.rpc.Code;
+import com.google.rpc.Status;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.util.List;
+
+/** Fake Datastore factory used for testing purposes when a true Datastore service is not needed. */
+public class MockDatastoreFactory extends DatastoreFactory {
+  private int nextStatus;
+  private Message nextResponse;
+  private Status nextError;
+  private IOException nextException;
+
+  private String lastPath;
+  private String lastMimeType;
+  private byte[] lastBody;
+  private List<String> lastCookies;
+  private String lastApiFormatHeaderValue;
+
+  public void setNextResponse(Message response) {
+    nextStatus = HttpStatusCodes.STATUS_CODE_OK;
+    nextResponse = response;
+    nextError = null;
+    nextException = null;
+  }
+
+  public void setNextError(int status, Code code, String message) {
+    nextStatus = status;
+    nextResponse = null;
+    nextError = makeErrorContent(message, code);
+    nextException = null;
+  }
+
+  public void setNextException(IOException exception) {
+    nextStatus = 0;
+    nextResponse = null;
+    nextError = null;
+    nextException = exception;
+  }
+
+  @Override
+  public HttpRequestFactory makeClient(DatastoreOptions options) {
+    HttpTransport transport =
+        new MockHttpTransport() {
+          @Override
+          public LowLevelHttpRequest buildRequest(String method, String url) {
+            return new MockLowLevelHttpRequest(url) {
+              @Override
+              public LowLevelHttpResponse execute() throws IOException {
+                lastPath = new GenericUrl(getUrl()).getRawPath();
+                lastMimeType = getContentType();
+                lastCookies = getHeaderValues("Cookie");
+                lastApiFormatHeaderValue =
+                    Iterables.getOnlyElement(getHeaderValues("X-Goog-Api-Format-Version"));
+                ByteArrayOutputStream out = new ByteArrayOutputStream();
+                getStreamingContent().writeTo(out);
+                lastBody = out.toByteArray();
+                if (nextException != null) {
+                  throw nextException;
+                }
+                MockLowLevelHttpResponse response =
+                    new MockLowLevelHttpResponse()
+                        .setStatusCode(nextStatus)
+                        .setContentType("application/x-protobuf");
+                if (nextError != null) {
+                  checkState(nextResponse == null);
+                  response.setContent(new TestableByteArrayInputStream(nextError.toByteArray()));
+                } else {
+                  response.setContent(new TestableByteArrayInputStream(nextResponse.toByteArray()));
+                }
+                return response;
+              }
+            };
+          }
+        };
+    Credential credential = options.getCredential();
+    return transport.createRequestFactory(credential);
+  }
+
+  public String getLastPath() {
+    return lastPath;
+  }
+
+  public String getLastMimeType() {
+    return lastMimeType;
+  }
+
+  public String getLastApiFormatHeaderValue() {
+    return lastApiFormatHeaderValue;
+  }
+
+  public byte[] getLastBody() {
+    return lastBody;
+  }
+
+  public List<String> getLastCookies() {
+    return lastCookies;
+  }
+
+  private static Status makeErrorContent(String message, Code code) {
+    return Status.newBuilder().setCode(code.getNumber()).setMessage(message).build();
+  }
+}