Daggerize ExportSnapshotServlet and CheckSnapshotServlet

Eradicate the last remnants of un-injectable servlets!

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=145598002

java/google/registry/export/ExportSnapshotAction.java

@@ -0,0 +1,72 @@
+// Copyright 2016 The Nomulus Authors. All Rights Reserved.
+//
+// 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 google.registry.export;
+
+import static google.registry.export.CheckSnapshotAction.enqueuePollTask;
+import static google.registry.request.Action.Method.POST;
+
+import google.registry.config.RegistryConfig;
+import google.registry.request.Action;
+import google.registry.request.Response;
+import google.registry.util.Clock;
+import google.registry.util.FormattingLogger;
+import javax.inject.Inject;
+
+/**
+ * Action to trigger a datastore backup job that writes a snapshot to Google Cloud Storage.
+ *
+ * <p>This is the first step of a four step workflow for exporting snapshots, with each step calling
+ * the next upon successful completion:
+ *
+ * <ol>
+ *   <li>The snapshot is exported to Google Cloud Storage (this action).
+ *   <li>The {@link CheckSnapshotAction} polls until the export is completed.
+ *   <li>The {@link LoadSnapshotAction} imports the data from GCS to BigQuery.
+ *   <li>The {@link UpdateSnapshotViewAction} updates the view in latest_snapshot.
+ * </ol>
+ */
+@Action(path = ExportSnapshotAction.PATH, method = POST, automaticallyPrintOk = true)
+public class ExportSnapshotAction implements Runnable {
+
+  /** Queue to use for enqueuing the task that will actually launch the backup. */
+  static final String QUEUE = "export-snapshot"; // See queue.xml.
+
+  static final String PATH = "/_dr/task/exportSnapshot"; // See web.xml.
+
+  /** Prefix to use for naming all snapshots that are started by this servlet. */
+  static final String SNAPSHOT_PREFIX = "auto_snapshot_";
+
+  private static final FormattingLogger logger = FormattingLogger.getLoggerForCallerClass();
+
+  @Inject Clock clock;
+  @Inject DatastoreBackupService backupService;
+  @Inject Response response;
+
+  @Inject
+  ExportSnapshotAction() {}
+
+  @Override
+  public void run() {
+    // Use a unique name for the snapshot so we can explicitly check its completion later.
+    String snapshotName = SNAPSHOT_PREFIX + clock.nowUtc().toString("YYYYMMdd_HHmmss");
+    backupService.launchNewBackup(
+        QUEUE, snapshotName, RegistryConfig.getSnapshotsBucket(), ExportConstants.getBackupKinds());
+    // Enqueue a poll task to monitor the backup and load reporting-related kinds into bigquery.
+    enqueuePollTask(snapshotName, ExportConstants.getReportingKinds());
+    String message = "Datastore backup started with name: " + snapshotName;
+    logger.info(message);
+    response.setPayload(message);
+  }
+}