Add request/auth package to Nomulus release

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=147087621

java/google/registry/request/auth/Auth.java

@@ -0,0 +1,67 @@
+// 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.request.auth;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/** Annotation used to configure authentication settings for Actions. */
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.TYPE)
+public @interface Auth {
+
+  /** Available methods for authentication. */
+  public enum AuthMethod {
+
+    /** App Engine internal authentication. Must always be provided as the first method. */
+    INTERNAL,
+
+    /** Authentication methods suitable for API-style access, such as OAuth 2. */
+    API,
+
+    /** Legacy authentication using cookie-based App Engine Users API. Must come last if present. */
+    LEGACY
+  }
+
+  /** User authorization policy options. */
+  public enum UserPolicy {
+
+    /** This action ignores end users; the only configured auth method must be INTERNAL. */
+    IGNORED,
+
+    /** No user policy is enforced; anyone can access this action. */
+    PUBLIC,
+
+    /**
+     * If there is a user, it must be an admin, as determined by isUserAdmin().
+     *
+     * <p>Note that, according to App Engine, anybody with access to the app in the GCP Console,
+     * including editors and viewers, is an admin.
+     */
+    ADMIN
+  }
+
+  /** Enabled authentication methods for this action. */
+  AuthMethod[] methods() default { AuthMethod.INTERNAL };
+
+  /** Required minimum level of authentication for this action. */
+  // TODO(mountford) This should probably default to APP eventually.
+  AuthLevel minimumLevel() default AuthLevel.NONE;
+
+  /** Required user authorization policy for this action. */
+  UserPolicy userPolicy() default UserPolicy.IGNORED;
+}