chrometophone/appengine/c2dm/com/google/android/c2dm/server/C2DMConfigLoader.java

/*
 * Copyright 2010 Google Inc.
 *
 * 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 com.google.android.c2dm.server;

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.logging.Level;
import java.util.logging.Logger;

import javax.jdo.JDOObjectNotFoundException;
import javax.jdo.PersistenceManager;
import javax.jdo.PersistenceManagerFactory;

import com.google.appengine.api.datastore.Key;
import com.google.appengine.api.datastore.KeyFactory;

/**
 * Stores config information related to data messaging.
 * 
 */
class C2DMConfigLoader {
    private final PersistenceManagerFactory PMF;
    private static final Logger log = Logger.getLogger(C2DMConfigLoader.class.getName());

    String currentToken;
    
    C2DMConfigLoader(PersistenceManagerFactory pmf) {
        this.PMF = pmf;
    }

    /**
     * Update the token. 
     * 
     * Called on "Update-Client-Auth" or when admins set a new token.
     * @param token
     */
    public void updateToken(String token) {
        if (token != null) {
            currentToken = token;
            PersistenceManager pm = PMF.getPersistenceManager();
            try {
                getDataMessagingConfig(pm).setAuthToken(token);
            } finally {
                pm.close();
            }
        }
    }
    
    /** 
     * Token expired
     */
    public void invalidateCachedToken() {
        currentToken = null;
    }

    /**
     * Return the auth token.
     *
     * It'll first memcache, if not found will use the database. 
     * 
     * @return
     */
    public String getToken() {
        if (currentToken == null) {
            currentToken = getDataMessagingConfig().getAuthToken();
        } 
        return currentToken;
    }
    
    public C2DMConfig getDataMessagingConfig() {
        PersistenceManager pm = PMF.getPersistenceManager();
        try {
            C2DMConfig dynamicConfig = getDataMessagingConfig(pm);
            return dynamicConfig;
        } finally {
            pm.close();
        }
    }

    private C2DMConfig getDataMessagingConfig(PersistenceManager pm) {
        Key key = KeyFactory.createKey(C2DMConfig.class.getSimpleName(), 1);
        C2DMConfig dmConfig = null;
        try {
            dmConfig = pm.getObjectById(C2DMConfig.class, key);
        } catch (JDOObjectNotFoundException e) {
            // Create a new JDO object
            dmConfig = new C2DMConfig();
            dmConfig.setKey(key);
            // Must be in classpath, before sending. Do not checkin !
            try {
                InputStream is = this.getClass().getClassLoader().getResourceAsStream("/dataMessagingToken.txt");
                if (is != null) {
                    BufferedReader reader = new BufferedReader(new InputStreamReader(is));
                    String token = reader.readLine();
                    dmConfig.setAuthToken(token);
                }
            } catch (Throwable t) {
                log.log(Level.SEVERE, 
                        "Can't load initial token, use admin console", t);
            }
            
            
            pm.makePersistent(dmConfig);
        }
        return dmConfig;
    }
}