Add initial implementation of YAML config file

This implements the basic framework that allows global YAML
configuration, per-environment custom configuration, and unit-
test-specific configuration.

TESTED=I deployed to alpha, ran some EPP commands through the
nomulus tool, and verified no errors.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=145422680

java/google/registry/BUILD

@@ -53,6 +53,7 @@ zip_file(
         "env/common/default/WEB-INF/logging.properties",
         "env/common/default/WEB-INF/queue.xml",
         "env/common/default/WEB-INF/web.xml",
+        "env/production/common/WEB-INF/nomulus-config.yaml",
         "env/production/default/WEB-INF/appengine-web.xml",
         "env/production/default/WEB-INF/cron.xml",
         "//java/google/registry/module/frontend:frontend_jar_deploy.jar",
@@ -60,6 +61,7 @@ zip_file(
     out = "registry_default.war",
     mappings = {
         "domain_registry/java/google/registry/env/common/default": "",
+        "domain_registry/java/google/registry/env/production/common": "",
         "domain_registry/java/google/registry/env/production/default": "",
         "domain_registry/java/google/registry/module/frontend": "WEB-INF/lib",
     },
@@ -75,12 +77,14 @@ zip_file(
         "env/common/backend/WEB-INF/logging.properties",
         "env/common/backend/WEB-INF/web.xml",
         "env/production/backend/WEB-INF/appengine-web.xml",
+        "env/production/common/WEB-INF/nomulus-config.yaml",
         "//java/google/registry/module/backend:backend_jar_deploy.jar",
     ],
     out = "registry_backend.war",
     mappings = {
         "domain_registry/java/google/registry/env/common/backend": "",
         "domain_registry/java/google/registry/env/production/backend": "",
+        "domain_registry/java/google/registry/env/production/common": "",
         "domain_registry/java/google/registry/module/backend": "WEB-INF/lib",
     },
     deps = [
@@ -94,12 +98,14 @@ zip_file(
     srcs = [
         "env/common/tools/WEB-INF/logging.properties",
         "env/common/tools/WEB-INF/web.xml",
+        "env/production/common/WEB-INF/nomulus-config.yaml",
         "env/production/tools/WEB-INF/appengine-web.xml",
         "//java/google/registry/module/tools:tools_jar_deploy.jar",
     ],
     out = "registry_tools.war",
     mappings = {
         "domain_registry/java/google/registry/env/common/tools": "",
+        "domain_registry/java/google/registry/env/production/common": "",
         "domain_registry/java/google/registry/env/production/tools": "",
         "domain_registry/java/google/registry/module/tools": "WEB-INF/lib",
     },
@@ -132,27 +138,43 @@ registry_ear_file(
 zip_file(
     name = "registry_default_sandbox_war",
     srcs = [
+        "env/sandbox/common/WEB-INF/nomulus-config.yaml",
         "env/sandbox/default/WEB-INF/appengine-web.xml",
         "env/sandbox/default/WEB-INF/cron.xml",
     ],
     out = "registry_default_sandbox.war",
-    mappings = {"domain_registry/java/google/registry/env/sandbox/default": ""},
+    mappings = {
+        "domain_registry/java/google/registry/env/sandbox/common": "",
+        "domain_registry/java/google/registry/env/sandbox/default": "",
+    },
     deps = [":registry_default_war"],
 )
 
 zip_file(
     name = "registry_backend_sandbox_war",
-    srcs = ["env/sandbox/backend/WEB-INF/appengine-web.xml"],
+    srcs = [
+        "env/sandbox/backend/WEB-INF/appengine-web.xml",
+        "env/sandbox/common/WEB-INF/nomulus-config.yaml",
+    ],
     out = "registry_backend_sandbox.war",
-    mappings = {"domain_registry/java/google/registry/env/sandbox/backend": ""},
+    mappings = {
+        "domain_registry/java/google/registry/env/sandbox/backend": "",
+        "domain_registry/java/google/registry/env/sandbox/common": "",
+    },
     deps = [":registry_backend_war"],
 )
 
 zip_file(
     name = "registry_tools_sandbox_war",
-    srcs = ["env/sandbox/tools/WEB-INF/appengine-web.xml"],
+    srcs = [
+        "env/sandbox/common/WEB-INF/nomulus-config.yaml",
+        "env/sandbox/tools/WEB-INF/appengine-web.xml",
+    ],
     out = "registry_tools_sandbox.war",
-    mappings = {"domain_registry/java/google/registry/env/sandbox/tools": ""},
+    mappings = {
+        "domain_registry/java/google/registry/env/sandbox/common": "",
+        "domain_registry/java/google/registry/env/sandbox/tools": "",
+    },
     deps = [":registry_tools_war"],
 )
 
@@ -178,27 +200,43 @@ registry_ear_file(
 zip_file(
     name = "registry_default_alpha_war",
     srcs = [
+        "env/alpha/common/WEB-INF/nomulus-config.yaml",
         "env/alpha/default/WEB-INF/appengine-web.xml",
         "env/alpha/default/WEB-INF/cron.xml",
     ],
     out = "registry_default_alpha.war",
-    mappings = {"domain_registry/java/google/registry/env/alpha/default": ""},
+    mappings = {
+        "domain_registry/java/google/registry/env/alpha/common": "",
+        "domain_registry/java/google/registry/env/alpha/default": "",
+    },
     deps = [":registry_default_war"],
 )
 
 zip_file(
     name = "registry_backend_alpha_war",
-    srcs = ["env/alpha/backend/WEB-INF/appengine-web.xml"],
+    srcs = [
+        "env/alpha/backend/WEB-INF/appengine-web.xml",
+        "env/alpha/common/WEB-INF/nomulus-config.yaml",
+    ],
     out = "registry_backend_alpha.war",
-    mappings = {"domain_registry/java/google/registry/env/alpha/backend": ""},
+    mappings = {
+        "domain_registry/java/google/registry/env/alpha/backend": "",
+        "domain_registry/java/google/registry/env/alpha/common": "",
+    },
     deps = [":registry_backend_war"],
 )
 
 zip_file(
     name = "registry_tools_alpha_war",
-    srcs = ["env/alpha/tools/WEB-INF/appengine-web.xml"],
+    srcs = [
+        "env/alpha/common/WEB-INF/nomulus-config.yaml",
+        "env/alpha/tools/WEB-INF/appengine-web.xml",
+    ],
     out = "registry_tools_alpha.war",
-    mappings = {"domain_registry/java/google/registry/env/alpha/tools": ""},
+    mappings = {
+        "domain_registry/java/google/registry/env/alpha/common": "",
+        "domain_registry/java/google/registry/env/alpha/tools": "",
+    },
     deps = [":registry_tools_war"],
 )
 
@@ -224,27 +262,43 @@ registry_ear_file(
 zip_file(
     name = "registry_default_crash_war",
     srcs = [
+        "env/crash/common/WEB-INF/nomulus-config.yaml",
         "env/crash/default/WEB-INF/appengine-web.xml",
         "env/crash/default/WEB-INF/cron.xml",
     ],
     out = "registry_default_crash.war",
-    mappings = {"domain_registry/java/google/registry/env/crash/default": ""},
+    mappings = {
+        "domain_registry/java/google/registry/env/crash/common": "",
+        "domain_registry/java/google/registry/env/crash/default": "",
+    },
     deps = [":registry_default_war"],
 )
 
 zip_file(
     name = "registry_backend_crash_war",
-    srcs = ["env/crash/backend/WEB-INF/appengine-web.xml"],
+    srcs = [
+        "env/crash/backend/WEB-INF/appengine-web.xml",
+        "env/crash/common/WEB-INF/nomulus-config.yaml",
+    ],
     out = "registry_backend_crash.war",
-    mappings = {"domain_registry/java/google/registry/env/crash/backend": ""},
+    mappings = {
+        "domain_registry/java/google/registry/env/crash/backend": "",
+        "domain_registry/java/google/registry/env/crash/common": "",
+    },
     deps = [":registry_backend_war"],
 )
 
 zip_file(
     name = "registry_tools_crash_war",
-    srcs = ["env/crash/tools/WEB-INF/appengine-web.xml"],
+    srcs = [
+        "env/crash/common/WEB-INF/nomulus-config.yaml",
+        "env/crash/tools/WEB-INF/appengine-web.xml",
+    ],
     out = "registry_tools_crash.war",
-    mappings = {"domain_registry/java/google/registry/env/crash/tools": ""},
+    mappings = {
+        "domain_registry/java/google/registry/env/crash/common": "",
+        "domain_registry/java/google/registry/env/crash/tools": "",
+    },
     deps = [":registry_tools_war"],
 )
 
@@ -269,24 +323,42 @@ registry_ear_file(
 
 zip_file(
     name = "registry_default_local_war",
-    srcs = ["env/local/default/WEB-INF/appengine-web.xml"],
+    srcs = [
+        "env/local/common/WEB-INF/nomulus-config.yaml",
+        "env/local/default/WEB-INF/appengine-web.xml",
+    ],
     out = "registry_default_local.war",
-    mappings = {"domain_registry/java/google/registry/env/local/default": ""},
+    mappings = {
+        "domain_registry/java/google/registry/env/local/common": "",
+        "domain_registry/java/google/registry/env/local/default": "",
+    },
     deps = [":registry_default_war"],
 )
 
 zip_file(
     name = "registry_backend_local_war",
-    srcs = ["env/local/backend/WEB-INF/appengine-web.xml"],
+    srcs = [
+        "env/local/backend/WEB-INF/appengine-web.xml",
+        "env/local/common/WEB-INF/nomulus-config.yaml",
+    ],
     out = "registry_backend_local.war",
-    mappings = {"domain_registry/java/google/registry/env/local/backend": ""},
+    mappings = {
+        "domain_registry/java/google/registry/env/local/backend": "",
+        "domain_registry/java/google/registry/env/local/common": "",
+    },
     deps = [":registry_backend_war"],
 )
 
 zip_file(
     name = "registry_tools_local_war",
-    srcs = ["env/local/tools/WEB-INF/appengine-web.xml"],
+    srcs = [
+        "env/local/common/WEB-INF/nomulus-config.yaml",
+        "env/local/tools/WEB-INF/appengine-web.xml",
+    ],
     out = "registry_tools_local.war",
-    mappings = {"domain_registry/java/google/registry/env/local/tools": ""},
+    mappings = {
+        "domain_registry/java/google/registry/env/local/common": "",
+        "domain_registry/java/google/registry/env/local/tools": "",
+    },
     deps = [":registry_tools_war"],
 )

java/google/registry/config/BUILD

@@ -7,7 +7,9 @@ licenses(["notice"])  # Apache 2.0
 java_library(
     name = "config",
     srcs = glob(["*.java"]),
+    resources = glob(["*.yaml"]),
     deps = [
+        "//java/google/registry/util",
         "@com_google_appengine_api_1_0_sdk",
         "@com_google_auto_value",
         "@com_google_code_findbugs_jsr305",
@@ -15,5 +17,6 @@ java_library(
         "@com_google_guava",
         "@joda_time",
         "@org_joda_money",
+        "@org_yaml_snakeyaml",
     ],
 )

java/google/registry/config/RegistryConfig.java

@@ -14,13 +14,15 @@
 
 package google.registry.config;
 
+import static com.google.common.base.Suppliers.memoize;
 import static google.registry.config.ConfigUtils.makeUrl;
+import static google.registry.config.YamlUtils.getConfigSettings;
 import static java.lang.annotation.RetentionPolicy.RUNTIME;
 import static org.joda.time.Duration.standardDays;
 
 import com.google.appengine.api.utils.SystemProperty;
-import com.google.common.base.Ascii;
 import com.google.common.base.Optional;
+import com.google.common.base.Supplier;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.net.HostAndPort;
@@ -83,8 +85,8 @@ public final class RegistryConfig {
 
     @Provides
     @Config("projectId")
-    public static String provideProjectId() {
-      return RegistryConfig.getProjectId();
+    public static String provideProjectId(RegistryConfigSettings config) {
+      return config.general.appEngineProjectId;
     }
 
     /**
@@ -362,8 +364,8 @@ public final class RegistryConfig {
      */
     @Provides
     @Config("eppResourceIndexBucketCount")
-    public static int provideEppResourceIndexBucketCount() {
-      return RegistryConfig.getEppResourceIndexBucketCount();
+    public static int provideEppResourceIndexBucketCount(RegistryConfigSettings config) {
+      return config.datastore.eppResourceIndexBucketsNum;
     }
 
     /**
@@ -893,8 +895,8 @@ public final class RegistryConfig {
      */
     @Provides
     @Config("stackdriverMaxQps")
-    public static int provideStackdriverMaxQps() {
-      return 30;
+    public static int provideStackdriverMaxQps(RegistryConfigSettings config) {
+      return config.monitoring.stackdriverMaxQps;
     }
 
     /**
@@ -905,8 +907,8 @@ public final class RegistryConfig {
      */
     @Provides
     @Config("stackdriverMaxPointsPerRequest")
-    public static int provideStackdriverMaxPointsPerRequest() {
-      return 200;
+    public static int provideStackdriverMaxPointsPerRequest(RegistryConfigSettings config) {
+      return config.monitoring.stackdriverMaxPointsPerRequest;
     }
 
     /**
@@ -917,8 +919,8 @@ public final class RegistryConfig {
      */
     @Provides
     @Config("metricsWriteInterval")
-    public static Duration provideMetricsWriteInterval() {
-      return Duration.standardSeconds(60);
+    public static Duration provideMetricsWriteInterval(RegistryConfigSettings config) {
+      return Duration.standardSeconds(config.monitoring.writeIntervalSeconds);
     }
 
     /**
@@ -1015,6 +1017,12 @@ public final class RegistryConfig {
       return "TheRegistrar";
     }
 
+    @Singleton
+    @Provides
+    static RegistryConfigSettings provideRegistryConfigSettings() {
+      return CONFIG_SETTINGS.get();
+    }
+
     /**
      * Returns the help path for the RDAP terms of service.
      *
@@ -1105,16 +1113,7 @@ public final class RegistryConfig {
    * Returns the App Engine project ID, which is based off the environment name.
    */
   public static String getProjectId() {
-    String prodProjectId = "domain-registry";
-    RegistryEnvironment environment = RegistryEnvironment.get();
-    switch (environment) {
-      case PRODUCTION:
-      case UNITTEST:
-      case LOCAL:
-        return prodProjectId;
-      default:
-        return prodProjectId + "-" + Ascii.toLowerCase(environment.name());
-    }
+    return CONFIG_SETTINGS.get().general.appEngineProjectId;
   }
 
   /**
@@ -1140,12 +1139,7 @@ public final class RegistryConfig {
    * @see google.registry.model.ofy.CommitLogBucket
    */
   public static int getCommitLogBucketCount() {
-    switch (RegistryEnvironment.get()) {
-      case UNITTEST:
-        return 3;
-      default:
-        return 100;
-    }
+    return CONFIG_SETTINGS.get().datastore.commitLogBucketsNum;
   }
 
   /**
@@ -1246,12 +1240,7 @@ public final class RegistryConfig {
    * Returns the number of {@code EppResourceIndex} buckets to be used.
    */
   public static int getEppResourceIndexBucketCount() {
-    switch (RegistryEnvironment.get()) {
-      case UNITTEST:
-        return 3;
-      default:
-        return 997;
-    }
+    return CONFIG_SETTINGS.get().datastore.eppResourceIndexBucketsNum;
   }
 
   /**
@@ -1266,6 +1255,19 @@ public final class RegistryConfig {
     }
   }
 
+  /**
+   * Memoizes loading of the {@link RegistryConfigSettings} POJO.
+   *
+   * <p>Memoizing without cache expiration is used because the app must be re-deployed in order to
+   * change the contents of the YAML config files.
+   */
+  private static final Supplier<RegistryConfigSettings> CONFIG_SETTINGS =
+      memoize(new Supplier<RegistryConfigSettings>() {
+        @Override
+        public RegistryConfigSettings get() {
+          return getConfigSettings();
+        }});
+
   /** Config values used for local and unit test environments. */
   public static class LocalTestConfig {
 

java/google/registry/config/RegistryConfigSettings.java

@@ -0,0 +1,49 @@
+// 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.config;
+
+/** The POJO that YAML config files are deserialized into. */
+public class RegistryConfigSettings {
+
+  public General general;
+
+  public Datastore datastore;
+
+  public Monitoring monitoring;
+
+  /** General configuration options that apply to the entire App Engine project. */
+  public static class General {
+
+    public String appEngineProjectId;
+  }
+
+  /** Configuration for Cloud Datastore. */
+  public static class Datastore {
+
+    public int commitLogBucketsNum;
+
+    public int eppResourceIndexBucketsNum;
+  }
+
+  /** Configuration for monitoring. */
+  public static class Monitoring {
+
+    public int stackdriverMaxQps;
+
+    public int stackdriverMaxPointsPerRequest;
+
+    public int writeIntervalSeconds;
+  }
+}

java/google/registry/config/YamlUtils.java

@@ -0,0 +1,122 @@
+// 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.config;
+
+import static google.registry.config.RegistryEnvironment.UNITTEST;
+import static google.registry.util.FormattingLogger.getLoggerForCallerClass;
+import static google.registry.util.ResourceUtils.readResourceUtf8;
+
+import com.google.common.io.CharStreams;
+import google.registry.util.FormattingLogger;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.Map;
+import org.yaml.snakeyaml.Yaml;
+
+/** Utility methods for dealing with YAML. */
+public final class YamlUtils {
+
+  private static final FormattingLogger logger = getLoggerForCallerClass();
+
+  private static final String CUSTOM_CONFIG_PATH = "WEB-INF/nomulus-config.yaml";
+  private static final String YAML_CONFIG_PROD =
+      readResourceUtf8(RegistryConfig.class, "default-config.yaml");
+  private static final String YAML_CONFIG_UNITTEST =
+      readResourceUtf8(RegistryConfig.class, "unittest-config.yaml");
+
+  /**
+   * Loads the {@link RegistryConfigSettings} POJO from the YAML configuration file(s).
+   *
+   * <p>The {@code default-config.yaml} file in this directory is loaded first, and a fatal error is
+   * thrown if it cannot be found or if there is an error parsing it. Separately, the custom config
+   * file located in {@code WEB-INF/nomulus-config.yaml} is also loaded and those values merged into
+   * the POJO. If the custom config file does not exist then an info notice is logged, but if it
+   * does exist and is invalid then a fatal error is thrown.
+   *
+   * <p>Unit tests load the {@code unittest-config.yaml} file for custom config.
+   */
+  static RegistryConfigSettings getConfigSettings() {
+    String yaml = YAML_CONFIG_PROD;
+    if (RegistryEnvironment.get() == UNITTEST) {
+      yaml = mergeYaml(yaml, YAML_CONFIG_UNITTEST);
+    } else {
+      try {
+        // We have to load the file this way because App Engine does not allow loading files in the
+        // WEB-INF directory using a class loader.
+        FileInputStream fin = new FileInputStream(new File(CUSTOM_CONFIG_PATH));
+        String customYaml = CharStreams.toString(new InputStreamReader(fin, "UTF-8"));
+        yaml = mergeYaml(yaml, customYaml);
+      } catch (IOException e) {
+        logger.warningfmt(
+            "There was no custom configuration file to load at %s", CUSTOM_CONFIG_PATH);
+      }
+    }
+    try {
+      return new Yaml().loadAs(yaml, RegistryConfigSettings.class);
+    } catch (Exception e) {
+      throw new IllegalStateException("Fatal error: Custom YAML configuration file is invalid", e);
+    }
+  }
+
+  /**
+   * Recursively merges two YAML documents together.
+   *
+   * <p>Any fields that are specified in customYaml will override fields of the same path in
+   * defaultYaml. Additional fields in customYaml that aren't specified in defaultYaml will be
+   * ignored. The schemas of all fields that are present must be identical, e.g. it is an error to
+   * override a field that has a Map value in the default YAML with a field of any other type in the
+   * custom YAML.
+   *
+   * <p>Only maps are handled recursively; lists are simply overridden in place as-is.
+   */
+  static String mergeYaml(String defaultYaml, String customYaml) {
+    try {
+      Yaml yaml = new Yaml();
+      Map<String, Object> defaultObj = loadAsMap(yaml, defaultYaml);
+      Map<String, Object> customObj = loadAsMap(yaml, customYaml);
+      Object mergedObj = mergeMaps(defaultObj, customObj);
+      logger.infofmt("Successfully loaded custom YAML configuration file.");
+      return yaml.dump(mergedObj);
+    } catch (Exception e) {
+      throw new IllegalStateException("Fatal error: Custom YAML configuration file is invalid", e);
+    }
+  }
+
+  private static Object mergeMaps(Map<String, Object> defaultMap, Map<String, Object> customMap) {
+    for (String key : defaultMap.keySet()) {
+      if (!customMap.containsKey(key)) {
+        continue;
+      }
+      Object defaultValue = defaultMap.get(key);
+      @SuppressWarnings("unchecked")
+      Object newValue =
+          (defaultValue instanceof Map)
+              ? mergeMaps(
+                  (Map<String, Object>) defaultValue, (Map<String, Object>) customMap.get(key))
+              : customMap.get(key);
+      defaultMap.put(key, newValue);
+    }
+    return defaultMap;
+  }
+
+  @SuppressWarnings("unchecked")
+  private static Map<String, Object> loadAsMap(Yaml yaml, String yamlString) {
+    return (Map<String, Object>) yaml.load(yamlString);
+  }
+
+  private YamlUtils() {}
+}

java/google/registry/config/default-config.yaml

@@ -0,0 +1,29 @@
+# This is the default configuration file for Nomulus. Do not make changes to it
+# unless you are writing new features that requires you to. To customize an
+# individual deployment or environment, create a nomulus-config.yaml file in the
+# WEB-INF/ directory overriding only the values you wish to change.
+
+general:
+  # Globally unique App Engine project ID
+  appEngineProjectId: domain-registry
+
+datastore:
+  # The number of commit log buckets in Datastore. Don't change after initial
+  # install.
+  commitLogBucketsNum: 100
+
+  # The number of EPP resource index buckets in Datastore. Don’t change after
+  # initial install.
+  eppResourceIndexBucketsNum: 997
+
+monitoring:
+  # Max queries per second for the Google Cloud Monitoring V3 (aka Stackdriver)
+  # API. The limit can be adjusted by contacting Cloud Support.
+  stackdriverMaxQps: 30
+
+  # Max number of points that can be sent to Stackdriver in a single
+  # TimeSeries.Create API call.
+  stackdriverMaxPointsPerRequest: 200
+
+  # How often metrics are exported to BigQuery.
+  writeIntervalSeconds: 60

java/google/registry/config/unittest-config.yaml

@@ -0,0 +1,6 @@
+# This is the configuration file used by unit tests. These values ARE NOT
+# SUITABLE for use in a real deployed environment.
+
+datastore:
+  commitLogBucketsNum: 3
+  eppResourceIndexBucketsNum: 3

java/google/registry/env/alpha/backend/WEB-INF/appengine-web.xml

@@ -12,6 +12,10 @@
     <idle-timeout>10m</idle-timeout>
   </basic-scaling>
 
+  <resource-files>
+    <include path="/WEB-INF/*.yaml"/>
+  </resource-files>
+
   <system-properties>
     <property name="java.util.logging.config.file"
               value="WEB-INF/logging.properties"/>

java/google/registry/env/alpha/common/WEB-INF/nomulus-config.yaml

@@ -0,0 +1,3 @@
+
+general:
+  appEngineProjectId: domain-registry-alpha

java/google/registry/env/alpha/default/WEB-INF/appengine-web.xml

@@ -12,6 +12,10 @@
     <idle-timeout>10m</idle-timeout>
   </basic-scaling>
 
+  <resource-files>
+    <include path="/WEB-INF/*.yaml"/>
+  </resource-files>
+
   <system-properties>
     <property name="java.util.logging.config.file"
               value="WEB-INF/logging.properties"/>

java/google/registry/env/alpha/tools/WEB-INF/appengine-web.xml

@@ -12,6 +12,10 @@
     <idle-timeout>5m</idle-timeout>
   </basic-scaling>
 
+  <resource-files>
+    <include path="/WEB-INF/*.yaml"/>
+  </resource-files>
+
   <system-properties>
     <property name="java.util.logging.config.file"
               value="WEB-INF/logging.properties"/>

java/google/registry/env/crash/backend/WEB-INF/appengine-web.xml

@@ -12,6 +12,10 @@
     <idle-timeout>10m</idle-timeout>
   </basic-scaling>
 
+  <resource-files>
+    <include path="/WEB-INF/*.yaml"/>
+  </resource-files>
+
   <system-properties>
     <property name="java.util.logging.config.file"
               value="WEB-INF/logging.properties"/>

java/google/registry/env/crash/common/WEB-INF/nomulus-config.yaml

@@ -0,0 +1,3 @@
+
+general:
+  appEngineProjectId: domain-registry-crash

java/google/registry/env/crash/default/WEB-INF/appengine-web.xml

@@ -12,6 +12,10 @@
     <idle-timeout>10m</idle-timeout>
   </basic-scaling>
 
+  <resource-files>
+    <include path="/WEB-INF/*.yaml"/>
+  </resource-files>
+
   <system-properties>
     <property name="java.util.logging.config.file"
               value="WEB-INF/logging.properties"/>

java/google/registry/env/crash/tools/WEB-INF/appengine-web.xml

@@ -12,6 +12,10 @@
     <idle-timeout>10m</idle-timeout>
   </basic-scaling>
 
+  <resource-files>
+    <include path="/WEB-INF/*.yaml"/>
+  </resource-files>
+
   <system-properties>
     <property name="java.util.logging.config.file"
               value="WEB-INF/logging.properties"/>

java/google/registry/env/local/backend/WEB-INF/appengine-web.xml

@@ -12,6 +12,10 @@
     <idle-timeout>10m</idle-timeout>
   </basic-scaling>
 
+  <resource-files>
+    <include path="/WEB-INF/*.yaml"/>
+  </resource-files>
+
   <system-properties>
     <property name="java.util.logging.config.file"
               value="WEB-INF/logging.properties"/>

java/google/registry/env/local/common/WEB-INF/nomulus-config.yaml

@@ -0,0 +1,3 @@
+
+general:
+  appEngineProjectId: domain-registry

java/google/registry/env/local/default/WEB-INF/appengine-web.xml

@@ -12,6 +12,9 @@
     <idle-timeout>10m</idle-timeout>
   </basic-scaling>
 
+  <resource-files>
+    <include path="/WEB-INF/*.yaml"/>
+  </resource-files>
 
   <system-properties>
     <property name="java.util.logging.config.file"

java/google/registry/env/local/tools/WEB-INF/appengine-web.xml

@@ -12,6 +12,10 @@
     <idle-timeout>10m</idle-timeout>
   </basic-scaling>
 
+  <resource-files>
+    <include path="/WEB-INF/*.yaml"/>
+  </resource-files>
+
   <system-properties>
     <property name="java.util.logging.config.file"
               value="WEB-INF/logging.properties"/>

java/google/registry/env/production/backend/WEB-INF/appengine-web.xml

@@ -12,6 +12,10 @@
     <idle-timeout>10m</idle-timeout>
   </basic-scaling>
 
+  <resource-files>
+    <include path="/WEB-INF/*.yaml"/>
+  </resource-files>
+
   <system-properties>
     <property name="java.util.logging.config.file"
               value="WEB-INF/logging.properties"/>

java/google/registry/env/production/common/WEB-INF/nomulus-config.yaml

@@ -0,0 +1,3 @@
+
+general:
+  appEngineProjectId: domain-registry

java/google/registry/env/production/default/WEB-INF/appengine-web.xml

@@ -12,6 +12,10 @@
     <idle-timeout>10m</idle-timeout>
   </basic-scaling>
 
+  <resource-files>
+    <include path="/WEB-INF/*.yaml"/>
+  </resource-files>
+
   <system-properties>
     <property name="java.util.logging.config.file"
               value="WEB-INF/logging.properties"/>

java/google/registry/env/production/tools/WEB-INF/appengine-web.xml

@@ -12,6 +12,10 @@
     <idle-timeout>10m</idle-timeout>
   </basic-scaling>
 
+  <resource-files>
+    <include path="/WEB-INF/*.yaml"/>
+  </resource-files>
+
   <system-properties>
     <property name="java.util.logging.config.file"
               value="WEB-INF/logging.properties"/>

java/google/registry/env/sandbox/backend/WEB-INF/appengine-web.xml

@@ -12,6 +12,10 @@
     <idle-timeout>10m</idle-timeout>
   </basic-scaling>
 
+  <resource-files>
+    <include path="/WEB-INF/*.yaml"/>
+  </resource-files>
+
   <system-properties>
     <property name="java.util.logging.config.file"
               value="WEB-INF/logging.properties"/>

java/google/registry/env/sandbox/common/WEB-INF/nomulus-config.yaml

@@ -0,0 +1,3 @@
+
+general:
+  appEngineProjectId: domain-registry-sandbox

java/google/registry/env/sandbox/default/WEB-INF/appengine-web.xml

@@ -12,6 +12,10 @@
     <idle-timeout>10m</idle-timeout>
   </basic-scaling>
 
+  <resource-files>
+    <include path="/WEB-INF/*.yaml"/>
+  </resource-files>
+
   <system-properties>
     <property name="java.util.logging.config.file"
               value="WEB-INF/logging.properties"/>

java/google/registry/env/sandbox/tools/WEB-INF/appengine-web.xml

@@ -12,6 +12,10 @@
     <idle-timeout>10m</idle-timeout>
   </basic-scaling>
 
+  <resource-files>
+    <include path="/WEB-INF/*.yaml"/>
+  </resource-files>
+
   <system-properties>
     <property name="java.util.logging.config.file"
               value="WEB-INF/logging.properties"/>

java/google/registry/repositories.bzl

@@ -105,7 +105,8 @@ def domain_registry_repositories(
     omit_org_mortbay_jetty=False,
     omit_org_mortbay_jetty_servlet_api=False,
     omit_org_mortbay_jetty_util=False,
-    omit_org_slf4j_api=False):
+    omit_org_slf4j_api=False,
+    omit_org_yaml_snakeyaml=False):
   """Imports dependencies for Nomulus."""
   domain_registry_bazel_check()
   if not omit_com_beust_jcommander:
@@ -276,6 +277,8 @@ def domain_registry_repositories(
     org_mortbay_jetty_util()
   if not omit_org_slf4j_api:
     org_slf4j_api()
+  if not omit_org_yaml_snakeyaml:
+    org_yaml_snakeyaml()
 
 def com_beust_jcommander():
   java_import_external(
@@ -1620,6 +1623,17 @@ def org_slf4j_api():
       licenses = ["notice"],  # MIT License
   )
 
+def org_yaml_snakeyaml():
+  java_import_external(
+      name = "org_yaml_snakeyaml",
+      licenses = ["notice"],  # Apache License, Version 2.0
+      jar_sha256 = "5666b36f9db46f06dd5a19d73bbff3b588d5969c0f4b8848fde0f5ec849430a5",
+      jar_urls = [
+          "http://maven.ibiblio.org/maven2/org/yaml/snakeyaml/1.17/snakeyaml-1.17.jar",
+          "http://repo1.maven.org/maven2/org/yaml/snakeyaml/1.17/snakeyaml-1.17.jar",
+      ],
+  )
+
 def _check_bazel_version(project, bazel_version):
   if "bazel_version" not in dir(native):
     fail("%s requires Bazel >=%s but was <0.2.1" % (project, bazel_version))

javatests/google/registry/config/YamlUtilsTest.java

@@ -0,0 +1,54 @@
+// 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.config;
+
+import static com.google.common.truth.Truth.assertThat;
+import static google.registry.config.YamlUtils.mergeYaml;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/** Unit tests for {@link YamlUtils}. */
+@RunWith(JUnit4.class)
+public class YamlUtilsTest {
+
+  @Test
+  public void testSuccess_mergeSimpleMaps() {
+    String defaultYaml = join("one: ay", "two: bee", "three: sea");
+    String customYaml = join("two: dee", "four: ignored");
+    assertThat(mergeYaml(defaultYaml, customYaml)).isEqualTo("{one: ay, two: dee, three: sea}\n");
+  }
+
+  @Test
+  public void testSuccess_mergeNestedMaps() {
+    String defaultYaml = join("non: ay", "nested:", "  blah: tim", "  neat: 12");
+    String customYaml = join("nested:", "  blah: max", "  extra: none");
+    assertThat(mergeYaml(defaultYaml, customYaml))
+        .isEqualTo(join("non: ay", "nested: {blah: max, neat: 12}"));
+  }
+
+  @Test
+  public void testSuccess_listsAreOverridden() {
+    String defaultYaml = join("non: ay", "list:", "  - foo", "  - bar", "  - baz");
+    String customYaml = join("list:", "  - crackle", "  - pop var");
+    assertThat(mergeYaml(defaultYaml, customYaml))
+        .isEqualTo(join("non: ay", "list: [crackle, pop var]"));
+  }
+
+  private static String join(CharSequence... strings) {
+    return String.join("\n", strings) + "\n";
+  }
+}