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

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;

/**
 * Stores config information related to data messaging.
 * 
 */
public class C2DMConfigLoader {
    private static final String TOKEN_FILE = "/dataMessagingToken.txt";
    private static final String API_KEY_FILE = "/dataMessagingApiKey.txt";
    private final PersistenceManagerFactory PMF;
    private static final Logger log = Logger.getLogger(C2DMConfigLoader.class.getName());

    private static final int C2DM_TOKEN = 1;
    private static final int GCM_API_KEY = 5001;

    String currentToken;
    String c2dmUrl;
    String currentApiKey;
    
    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, TOKEN_FILE, C2DM_TOKEN).setAuthToken(token);
            } finally {
                pm.close();
            }
        }
    }
    
    /** 
     * Token expired
     */
    public void invalidateCachedToken() {
        currentToken = null;
    }

    /**
     * Return the auth token from the database. Should be called 
     * only if the old token expired.
     */
    public String getToken() {
        if (currentToken == null) {
            currentToken = getDataMessagingConfig(TOKEN_FILE, C2DM_TOKEN).getAuthToken();
        } 
        return currentToken;
    }
    
    public String getGcmApiKey() {
      if (currentApiKey == null) {
        currentApiKey = getDataMessagingConfig(API_KEY_FILE, GCM_API_KEY).getAuthToken();
    } 
      return currentApiKey;
    }
    
    public String getC2DMUrl() {
        if (c2dmUrl == null) {
            c2dmUrl = getDataMessagingConfig(TOKEN_FILE, C2DM_TOKEN).getC2DMUrl();
        }
        return c2dmUrl;
    }

    private C2DMConfig getDataMessagingConfig(String file, int index) {
        PersistenceManager pm = PMF.getPersistenceManager();
        try {
            C2DMConfig dynamicConfig = getDataMessagingConfig(pm, file, index);
            return dynamicConfig;
        } finally {
            pm.close();
        }
    }

    private C2DMConfig getDataMessagingConfig(PersistenceManager pm, String file, int index) {
        Key key = KeyFactory.createKey(C2DMConfig.class.getSimpleName(), index);
        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 = C2DMConfigLoader.class.getClassLoader().getResourceAsStream(file);
                String token;
                if (is != null) {
                    BufferedReader reader = new BufferedReader(new InputStreamReader(is));
                    token = reader.readLine();
                } else {
                  // happens on developement: delete entity from viewer, change
                  // token below, and run it again
                  log.log(Level.WARNING, "File " + TOKEN_FILE +
                      " not found on classpath, using hardcoded token");
                  token = "please_change_me";
                }
                dmConfig.setAuthToken(token);
            } catch (Throwable t) {
                log.log(Level.SEVERE, 
                        "Can't load initial token, use admin console", t);
            }
            
            
            pm.makePersistent(dmConfig);
        }
        return dmConfig;
    }
}