Implement login/logout commands

Refactor the auth code into its own dagger module, add tests and use the new interfaces to implement the login and logout commands.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=149108266

java/google/registry/tools/AuthModule.java

@@ -0,0 +1,155 @@
+// 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.tools;
+
+import static java.nio.charset.StandardCharsets.UTF_8;
+
+import com.google.api.client.auth.oauth2.Credential;
+import com.google.api.client.extensions.java6.auth.oauth2.AuthorizationCodeInstalledApp;
+import com.google.api.client.extensions.jetty.auth.oauth2.LocalServerReceiver;
+import com.google.api.client.googleapis.auth.oauth2.GoogleAuthorizationCodeFlow;
+import com.google.api.client.googleapis.auth.oauth2.GoogleClientSecrets;
+import com.google.api.client.http.javanet.NetHttpTransport;
+import com.google.api.client.json.JsonFactory;
+import com.google.api.client.util.store.AbstractDataStoreFactory;
+import com.google.api.client.util.store.FileDataStoreFactory;
+import com.google.common.base.Joiner;
+import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.Ordering;
+import dagger.Module;
+import dagger.Provides;
+import google.registry.config.RegistryConfig.Config;
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.lang.annotation.Documented;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import javax.inject.Qualifier;
+import javax.inject.Singleton;
+
+/**
+ * Module providing the dependency graph for authorization credentials.
+ */
+@Module
+public class AuthModule {
+
+  private static final File DATA_STORE_DIR =
+      new File(System.getProperty("user.home"), ".config/nomulus/credentials");
+
+  @Provides
+  public Credential provideCredential(
+      GoogleAuthorizationCodeFlow flow,
+      @ClientScopeQualifier String clientScopeQualifier) {
+    try {
+      // Try to load the credentials, throw an exception if we fail.
+      Credential credential = flow.loadCredential(clientScopeQualifier);
+      if (credential == null) {
+        throw new LoginRequiredException();
+      }
+      return credential;
+    } catch (IOException ex) {
+      throw new RuntimeException(ex);
+    }
+  }
+
+  @Provides
+  GoogleAuthorizationCodeFlow provideAuthorizationCodeFlow(
+      JsonFactory jsonFactory,
+      GoogleClientSecrets clientSecrets,
+      @Config("requiredOauthScopes") ImmutableSet<String> requiredOauthScopes,
+      AbstractDataStoreFactory dataStoreFactory) {
+    try {
+      return new GoogleAuthorizationCodeFlow.Builder(
+              new NetHttpTransport(), jsonFactory, clientSecrets, requiredOauthScopes)
+          .setDataStoreFactory(dataStoreFactory)
+          .build();
+    } catch (IOException ex) {
+      throw new RuntimeException(ex);
+    }
+  }
+
+  @Provides
+  AuthorizationCodeInstalledApp provideAuthorizationCodeInstalledApp(
+      GoogleAuthorizationCodeFlow flow) {
+    return new AuthorizationCodeInstalledApp(flow, new LocalServerReceiver());
+  }
+
+  @Provides
+  GoogleClientSecrets provideClientSecrets(
+      @Config("clientSecretFilename") String clientSecretFilename, JsonFactory jsonFactory) {
+    try {
+      // Load the client secrets file.
+      InputStream secretResourceStream = getClass().getResourceAsStream(clientSecretFilename);
+      if (secretResourceStream == null) {
+        throw new RuntimeException("No client secret file found: " + clientSecretFilename);
+      }
+      return GoogleClientSecrets.load(jsonFactory,
+          new InputStreamReader(secretResourceStream, UTF_8));
+    } catch (IOException ex) {
+      throw new RuntimeException(ex);
+    }
+  }
+
+  @Provides
+  @OAuthClientId String provideClientId(GoogleClientSecrets clientSecrets) {
+    return clientSecrets.getDetails().getClientId();
+  }
+
+  @Provides
+  @ClientScopeQualifier String provideClientScopeQualifier(
+      @OAuthClientId String clientId, @Config("requiredOauthScopes") ImmutableSet<String> scopes) {
+    return clientId + " " + Joiner.on(" ").join(Ordering.natural().sortedCopy(scopes));
+  }
+
+  @Provides
+  @Singleton
+  public AbstractDataStoreFactory provideDataStoreFactory() {
+    try {
+      return new FileDataStoreFactory(DATA_STORE_DIR);
+    } catch (IOException ex) {
+      throw new RuntimeException(ex);
+    }
+  }
+
+  /** Wrapper class to hold the login() function. */
+  public static class Authorizer {
+    /** Initiate the login flow. */
+    public static void login(
+        GoogleAuthorizationCodeFlow flow,
+        @ClientScopeQualifier String clientScopeQualifier) throws Exception {
+      new AuthorizationCodeInstalledApp(flow, new LocalServerReceiver())
+          .authorize(clientScopeQualifier);
+    }
+  }
+
+  /** Raised when we need a user login. */
+  public static class LoginRequiredException extends RuntimeException {
+    public LoginRequiredException() {}
+  }
+
+  /** Dagger qualifier for the credential qualifier consisting of client and scopes. */
+  @Qualifier
+  @Documented
+  @Retention(RetentionPolicy.RUNTIME)
+  public @interface ClientScopeQualifier {}
+
+  /** Dagger qualifier for the OAuth2 client id. */
+  @Qualifier
+  @Documented
+  @Retention(RetentionPolicy.RUNTIME)
+  public @interface OAuthClientId {}
+}