Add mapreduce for RDE hosts import

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=136766682

java/google/registry/rde/RdeHostImportAction.java

@@ -0,0 +1,114 @@
+// 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.rde;
+
+import static google.registry.mapreduce.MapreduceRunner.PARAM_MAP_SHARDS;
+import static google.registry.model.ofy.ObjectifyService.ofy;
+import static google.registry.rde.RdeModule.PATH;
+import static google.registry.util.PipelineUtils.createJobPath;
+
+import com.google.appengine.tools.cloudstorage.GcsService;
+import com.google.appengine.tools.cloudstorage.GcsServiceFactory;
+import com.google.appengine.tools.cloudstorage.RetryParams;
+import com.google.appengine.tools.mapreduce.Mapper;
+import com.google.common.base.Optional;
+import com.google.common.collect.ImmutableList;
+import google.registry.config.ConfigModule;
+import google.registry.config.ConfigModule.Config;
+import google.registry.gcs.GcsUtils;
+import google.registry.mapreduce.MapreduceRunner;
+import google.registry.model.host.HostResource;
+import google.registry.request.Action;
+import google.registry.request.Parameter;
+import google.registry.request.Response;
+import google.registry.util.SystemClock;
+import javax.inject.Inject;
+
+/**
+ * A mapreduce that imports hosts from an escrow file.
+ *
+ * <p>Specify the escrow file to import with the "path" parameter.
+ */
+@Action(path = "/_dr/task/importRdeHosts")
+public class RdeHostImportAction implements Runnable {
+
+  private static final GcsService GCS_SERVICE =
+      GcsServiceFactory.createGcsService(RetryParams.getDefaultInstance());
+
+  private final MapreduceRunner mrRunner;
+  private final Response response;
+  private final String importBucketName;
+  private final String importFileName;
+  private final Optional<Integer> mapShards;
+
+  @Inject
+  public RdeHostImportAction(
+      MapreduceRunner mrRunner,
+      Response response,
+      @Config("rdeImportBucket") String importBucketName,
+      @Parameter(PATH) String importFileName,
+      @Parameter(PARAM_MAP_SHARDS) Optional<Integer> mapShards) {
+    this.mrRunner = mrRunner;
+    this.response = response;
+    this.importBucketName = importBucketName;
+    this.importFileName = importFileName;
+    this.mapShards = mapShards;
+  }
+
+  @Override
+  public void run() {
+    response.sendJavaScriptRedirect(createJobPath(mrRunner
+        .setJobName("Import hosts from escrow file")
+        .setModuleName("backend")
+        .runMapOnly(
+            new RdeHostImportMapper(importBucketName),
+            ImmutableList.of(new RdeHostInput(mapShards, importBucketName, importFileName)))));
+  }
+
+  /** Mapper to import hosts from an escrow file. */
+  public static class RdeHostImportMapper extends Mapper<HostResource, Void, Void> {
+
+    private static final long serialVersionUID = -2898753709127134419L;
+    private final String importBucketName;
+    private transient RdeImportUtils importUtils;
+
+    public RdeHostImportMapper(String importBucketName) {
+      this.importBucketName = importBucketName;
+    }
+
+    private RdeImportUtils getImportUtils() {
+      if (importUtils == null) {
+        importUtils = createRdeImportUtils();
+      }
+      return importUtils;
+    }
+
+    /**
+     * Creates a new instance of RdeImportUtils.
+     */
+    private RdeImportUtils createRdeImportUtils() {
+      return new RdeImportUtils(
+          ofy(),
+          new SystemClock(),
+          importBucketName,
+          new GcsUtils(GCS_SERVICE, ConfigModule.provideGcsBufferSize()));
+    }
+
+    @Override
+    public void map(HostResource host) {
+      getImportUtils().importHost(host);
+    }
+  }
+}