Add golden files for request component routing maps

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=157026188

javatests/google/registry/testing/GoldenFileTestHelper.java

@@ -0,0 +1,74 @@
+// Copyright 2017 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.testing;
+
+import static com.google.common.truth.Truth.assert_;
+import static google.registry.util.ResourceUtils.readResourceUtf8;
+
+import com.google.common.base.Joiner;
+import java.net.MalformedURLException;
+import java.net.URL;
+
+/**
+ * Helper class to compare a string against a golden file and print out update instructions if
+ * necessary.
+ */
+public class GoldenFileTestHelper {
+
+  private static final String UPDATE_COMMAND =
+      "google.registry.tools.RegistryTool -e localhost %1$s >javatests%2$s";
+
+  private static final String UPDATE_INSTRUCTIONS =
+      Joiner.on('\n')
+          .join(
+              "",
+              "-------------------------------------------------------------------------------",
+              "Your changes affect the %3$s. To update the checked-in version, run:",
+              UPDATE_COMMAND,
+              "");
+
+  private static String getPathProper(URL url) throws MalformedURLException {
+    String protocol = url.getProtocol();
+    if (protocol.equals("jar")) {
+      url = new URL(url.getPath());
+      protocol = url.getProtocol();
+    }
+    if (protocol.equals("file")) {
+      String[] components = url.getPath().split("!");
+      if (components.length >= 2) {
+        return components[1];
+      }
+    }
+    return url.getPath();
+  }
+
+  public static void testGoldenFile(
+      String actualValue,
+      URL goldenFileUrl,
+      String goldenFileDescription,
+      String nomulusCommand)
+      throws Exception {
+    // Don't use Truth's isEqualTo() because the output is huge and unreadable for large files.
+    if (!actualValue.equals(readResourceUtf8(goldenFileUrl).trim())) {
+      assert_()
+          .fail(
+              String.format(
+                  UPDATE_INSTRUCTIONS,
+                  nomulusCommand,
+                  getPathProper(goldenFileUrl),
+                  goldenFileDescription));
+    }
+  }
+}