components/camel-google-mail/src/main/java/org/apache/camel/component/google/mail/BatchGoogleMailClientFactory.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.camel.component.google.mail;

import com.google.api.client.auth.oauth2.Credential;
import com.google.api.client.googleapis.auth.oauth2.GoogleCredential;
import com.google.api.client.http.javanet.NetHttpTransport;
import com.google.api.client.json.jackson2.JacksonFactory;
import com.google.api.services.gmail.Gmail;

import org.apache.camel.RuntimeCamelException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class BatchGoogleMailClientFactory implements GoogleMailClientFactory {
    private static final Logger LOG = LoggerFactory.getLogger(BatchGoogleMailClientFactory.class);
    private NetHttpTransport transport;
    private JacksonFactory jsonFactory;

    public BatchGoogleMailClientFactory() {
        this.transport = new NetHttpTransport();
        this.jsonFactory = new JacksonFactory();
    }

    @Override
    public Gmail makeClient(String clientId, String clientSecret, String applicationName, String refreshToken, String accessToken) {
        if (clientId == null || clientSecret == null) {
            throw new IllegalArgumentException("clientId and clientSecret are required to create Gmail client.");
        }
        try {
            Credential credential = authorize(clientId, clientSecret);

            if (refreshToken != null && !"".equals(refreshToken)) {
                credential.setRefreshToken(refreshToken);
            }
            if (accessToken != null && !"".equals(accessToken)) {
                credential.setAccessToken(accessToken);
            }
            return new Gmail.Builder(transport, jsonFactory, credential).setApplicationName(applicationName).build();
        } catch (Exception e) {
            throw new RuntimeCamelException("Could not create Gmail client.", e);
        }
    }

    // Authorizes the installed application to access user's protected data.
    private Credential authorize(String clientId, String clientSecret) throws Exception {
        // authorize
        return new GoogleCredential.Builder().setJsonFactory(jsonFactory).setTransport(transport).setClientSecrets(clientId, clientSecret).build();
    }
}