So, Google used to have a nice page where they gave code sample on how to implement a GCM Xmpp server on this page: https://developers.google.com/cloud-messaging/ccs
I had bookmarked this answer anytime I wanted to view the implementation Confused about Google GCM XMPP
But everything linked from in that answer is gone. Google deleted them.
But now, they have removed everything, and added a page that just explains what it does. Sure, but the sample java code would be nice. I tried to go to the sample site on github that they link to https://github.com/google/gcm
but it only provides samples of HTTP GCM server version.
Can somebody point me to a working code sample please? Or Is there a library out there that would work with c# at all? if not, I would just settle with the java version too.
Thanks.
Here is one I wrote for a class example (with some non-XMPP parts deleted to keep it small enough so I can post the code, but have the full server at http://people.eku.edu/styere/GcmPushServer.java):
// derived from https://developer.android.com/google/gcm/ccs.html import javax.swing.*; import java.awt.*; import java.awt.event.*; //import javax.swing.JScrollPane; //import javax.swing.SwingUtilities; import org.jivesoftware.smack.ConnectionConfiguration; import org.jivesoftware.smack.ConnectionConfiguration.SecurityMode; import org.jivesoftware.smack.ConnectionListener; import org.jivesoftware.smack.PacketInterceptor; import org.jivesoftware.smack.PacketListener; import org.jivesoftware.smack.SmackException; import org.jivesoftware.smack.SmackException.NotConnectedException; import org.jivesoftware.smack.XMPPConnection; import org.jivesoftware.smack.XMPPException; import org.jivesoftware.smack.filter.PacketTypeFilter; import org.jivesoftware.smack.packet.DefaultPacketExtension; import org.jivesoftware.smack.packet.Message; import org.jivesoftware.smack.packet.Packet; import org.jivesoftware.smack.packet.PacketExtension; import org.jivesoftware.smack.provider.PacketExtensionProvider; import org.jivesoftware.smack.provider.ProviderManager; import org.jivesoftware.smack.tcp.XMPPTCPConnection; import org.jivesoftware.smack.util.StringUtils; import org.json.simple.JSONValue; import org.json.simple.JSONObject; import org.json.simple.parser.ParseException; import org.xmlpull.v1.XmlPullParser; import java.io.IOException; import java.util.HashMap; import java.util.Map; import java.util.UUID; import java.text.DateFormat; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.ArrayList; import java.util.Enumeration; import java.util.Random; import java.net.*; import java.io.*; import java.util.*; import javax.net.ssl.SSLSocketFactory; import javax.net.ssl.HttpsURLConnection; // list of all users and associated devices class UserList { // (--deleted--) // constructor/read existing data from file public UserList() { // (--deleted--) } // add a new device to an existing user (called from networking thread) // duplicate IDs are quietly accepted public synchronized void addDevice( String uname, String newRegToken ) { // (--deleted--) } // generate a group address/notification key // !!!!!!!!!!!!!!! W A R N I N G !!!!!!!!!!!!!!! // If the group addr/notification key is lost, it currently CANNOT be recovered/rebuilt public String createNotificationKey( String nKeyName, String addr ) { String[] idset = new String[1]; idset[0] = addr; String newGroupAddr; try { // create a https connection to create the notification_key URL url = new URL( "https://android.googleapis.com/gcm/notification" ); HttpsURLConnection conn = (HttpsURLConnection)url.openConnection(); // send as a POST request conn.setRequestMethod("POST"); // add request parameters conn.addRequestProperty( "project_id", ""+GcmPushServer.senderId ); conn.addRequestProperty( "Authorization", "key="+GcmPushServer.password ); // use "set" since this may already exist conn.setRequestProperty( "Content-Type", "application/json" ); // create data to send with request Map<String,Object> sendData = new HashMap<>(); // create a new notification key sendData.put( "operation", "create" ); sendData.put( "notification_key_name", (--deleted--) ); sendData.put( "registration_ids", (--deleted--) ); String strData = JSONValue.toJSONString(sendData); // Send post request conn.setDoOutput(true); DataOutputStream wr = new DataOutputStream(conn.getOutputStream()); wr.writeBytes( strData ); wr.flush(); wr.close(); // successful? int rc = conn.getResponseCode(); //System.out.println("ResponseCode = " + rc ); // read the response Scanner input = new Scanner( conn.getInputStream() ); String resp=""; // read/display lines while( input.hasNextLine() ) { String s = input.nextLine(); resp += s; } //System.out.println("Response content: " + resp); if ( rc == HttpsURLConnection.HTTP_OK ) { JSONObject obj = (JSONObject) JSONValue.parse(resp); newGroupAddr = (String) obj.get( "notification_key" ); //System.out.println(" new notification_key: " + newGroupAddr ); return newGroupAddr; } else { } } catch ( Exception e ) { //System.out.println("-- Exception: " + e.getMessage() ); } return null; } // add/delete a single address to/from a notification key // (add if doAdd is true, delete otherwise) // removing final address will quietly delete the key public static void modifyNotificationKey( String nKeyName, String nKey, String addr, boolean doAdd ) { String[] idset = new String[1]; idset[0] = addr; try { // create a https connection to create the notification_key URL url = new URL( "https://android.googleapis.com/gcm/notification" ); HttpsURLConnection conn = (HttpsURLConnection)url.openConnection(); // send as a POST request conn.setRequestMethod("POST"); // add request parameters conn.addRequestProperty( "project_id", ""+GcmPushServer.senderId ); conn.addRequestProperty( "Authorization", "key="+GcmPushServer.password ); // use "set" since this may already exist conn.setRequestProperty( "Content-Type", "application/json" ); // create data to send with request Map<String,Object> sendData = new HashMap<>(); // create a new notification key sendData.put( "operation", doAdd? "add" : "remove" ); // add or delete key? sendData.put( "notification_key_name", (--deleted--) ); sendData.put( "notification_key", (--deleted--) ); sendData.put( "registration_ids", (--deleted--) ); String strData = JSONValue.toJSONString(sendData); //System.out.println("genGroupAddress POST data: " + strData ); // Send post request conn.setDoOutput(true); DataOutputStream wr = new DataOutputStream(conn.getOutputStream()); wr.writeBytes( strData ); wr.flush(); wr.close(); //conn.openConnection(); // successful? int rc = conn.getResponseCode(); //System.out.println("ResponseCode = " + rc ); Scanner input = new Scanner( conn.getInputStream() ); // read/display lines while( input.hasNextLine() ) { System.out.println("Response content:"); String s = input.nextLine(); System.out.println( s ); } } catch ( Exception e ) { // do nothing } } } // text area for log messages class LogTextArea extends JTextArea { // update the "log" with the specified message public void logMessage( String msg ) { // (--deleted--) } } class CcsServer { private static final String GCM_SERVER = "gcm.googleapis.com"; private static final int GCM_PORT = 5235; private static final String GCM_ELEMENT_NAME = "gcm"; private static final String GCM_NAMESPACE = "google:mobile:data"; // display/log area LogTextArea logArea; UserList users; CcsServer( LogTextArea lta, UserList u ) { logArea = lta; users = u; } static { ProviderManager.addExtensionProvider(GCM_ELEMENT_NAME, GCM_NAMESPACE, new PacketExtensionProvider() { @Override public PacketExtension parseExtension(XmlPullParser parser) throws Exception { String json = parser.nextText(); return new GcmPacketExtension(json); } }); } private XMPPConnection connection; /** * Indicates whether the connection is in draining state, which means that it * will not accept any new downstream messages. */ protected volatile boolean connectionDraining = false; /** * Sends a downstream message to GCM. * * @return true if the message has been successfully sent. */ public boolean sendDownstreamMessage(String jsonRequest) throws NotConnectedException { if (!connectionDraining) { send(jsonRequest); return true; } logArea.logMessage("Dropping downstream message since the connection is draining"); return false; } /** * Returns a random message id to uniquely identify a message. * * <p>Note: This is generated by a pseudo random number generator for * illustration purpose, and is not guaranteed to be unique. */ public String nextMessageId() { return "m-" + UUID.randomUUID().toString(); } /** * Sends a packet with contents provided. */ protected void send(String jsonRequest) throws NotConnectedException { Packet request = new GcmPacketExtension(jsonRequest).toPacket(); connection.sendPacket(request); } /** * Handles an upstream data message from a device application. * * <p>This sample echo server sends an echo message back to the device. * Subclasses should override this method to properly process upstream messages. */ protected void handleUpstreamMessage(Map<String, Object> jsonObject) { // PackageName of the application that sent this message. String category = (String) jsonObject.get("category"); String from = (String) jsonObject.get("from"); @SuppressWarnings("unchecked") Map<String, String> payload = (Map<String, String>) jsonObject.get("data"); // what type of upstream message is this? if ( ! payload.containsKey( "my_action" ) ) { // Hmmm - this shouldn't happen! logArea.logMessage( "handleUpstreamMessage - incoming message is missing my_action" ); // just ignore the message return; } // what action do they want? String my_action = (String) payload.get( "my_action" ); if ( my_action.equals( "edu.eku.styere.gcmpushclient.REGISTER" ) ) { // registration request String username = (String) payload.get( "username" ); logArea.logMessage( "Registration request: user=" + username + ", ID/Token=" + from ); // save the information users.addDevice( username, from ); return; } else { // take default action of echoing the message payload.put("ECHO", "Application: " + category); // Send an ECHO response back String echo = createJsonMessage(from, nextMessageId(), payload, "echo:CollapseKey", null, false); try { sendDownstreamMessage(echo); } catch (NotConnectedException e) { logArea.logMessage( "Not connected anymore, echo message is not sent: " + e.getMessage() ); } } } /** * Handles an ACK. * * <p>Logs a INFO message, but subclasses could override it to * properly handle ACKs. */ protected void handleAckReceipt(Map<String, Object> jsonObject) { String messageId = (String) jsonObject.get("message_id"); String from = (String) jsonObject.get("from"); logArea.logMessage( "handleAckReceipt() from: " + from + ", messageId: " + messageId ); } /** * Handles a NACK. * * <p>Logs a INFO message, but subclasses could override it to * properly handle NACKs. */ protected void handleNackReceipt(Map<String, Object> jsonObject) { String messageId = (String) jsonObject.get("message_id"); String from = (String) jsonObject.get("from"); logArea.logMessage( "handleNackReceipt() from: " + from + ", messageId: " + messageId ); } protected void handleControlMessage(Map<String, Object> jsonObject) { logArea.logMessage( "handleControlMessage(): " + jsonObject ); String controlType = (String) jsonObject.get("control_type"); if ("CONNECTION_DRAINING".equals(controlType)) { connectionDraining = true; } else { logArea.logMessage( "Unrecognised control type: " + controlType + ". This could "+ "happen if new features are " + "added to the CCS protocol." ); } } /** * Creates a JSON encoded GCM message. * * @param to RegistrationId of the target device (Required). * @param messageId Unique messageId for which CCS sends an * "ack/nack" (Required). * @param payload Message content intended for the application. (Optional). * @param collapseKey GCM collapse_key parameter (Optional). * @param timeToLive GCM time_to_live parameter (Optional). * @param delayWhileIdle GCM delay_while_idle parameter (Optional). * @return JSON encoded GCM message. */ public static String createJsonMessage(String to, String messageId, Map<String, String> payload, String collapseKey, Long timeToLive, Boolean delayWhileIdle) { Map<String, Object> message = new HashMap<String, Object>(); message.put("to", to); if (collapseKey != null) { message.put("collapse_key", collapseKey); } if (timeToLive != null) { message.put("time_to_live", timeToLive); } if (delayWhileIdle != null && delayWhileIdle) { message.put("delay_while_idle", true); } message.put("message_id", messageId); message.put("data", payload); return JSONValue.toJSONString(message); } /** * Creates a JSON encoded ACK message for an upstream message received * from an application. * * @param to RegistrationId of the device who sent the upstream message. * @param messageId messageId of the upstream message to be acknowledged to CCS. * @return JSON encoded ack. */ protected static String createJsonAck(String to, String messageId) { Map<String, Object> message = new HashMap<String, Object>(); message.put("message_type", "ack"); message.put("to", to); message.put("message_id", messageId); return JSONValue.toJSONString(message); } /** * Connects to GCM Cloud Connection Server using the supplied credentials. * * @param senderId Your GCM project number * @param apiKey API Key of your project */ public void connect(long senderId, String apiKey) throws XMPPException, IOException, SmackException { ConnectionConfiguration config = new ConnectionConfiguration(GCM_SERVER, GCM_PORT); config.setSecurityMode(SecurityMode.enabled); config.setReconnectionAllowed(true); config.setRosterLoadedAtLogin(false); config.setSendPresence(false); config.setSocketFactory(SSLSocketFactory.getDefault()); connection = new XMPPTCPConnection(config); connection.connect(); connection.addConnectionListener( new LoggingConnectionListener() ); // Handle incoming packets connection.addPacketListener(new PacketListener() { @Override public void processPacket(Packet packet) { logArea.logMessage( "Received: " + packet.toXML() ); Message incomingMessage = (Message) packet; GcmPacketExtension gcmPacket = (GcmPacketExtension) incomingMessage. getExtension(GCM_NAMESPACE); String json = gcmPacket.getJson(); try { @SuppressWarnings("unchecked") Map<String, Object> jsonObject = (Map<String, Object>) JSONValue. parseWithException(json); // present for "ack"/"nack", null otherwise Object messageType = jsonObject.get("message_type"); if (messageType == null) { // Normal upstream data message handleUpstreamMessage(jsonObject); // Send ACK to CCS String messageId = (String) jsonObject.get("message_id"); String from = (String) jsonObject.get("from"); String ack = createJsonAck(from, messageId); send(ack); } else if ("ack".equals(messageType.toString())) { // Process Ack handleAckReceipt(jsonObject); } else if ("nack".equals(messageType.toString())) { // Process Nack handleNackReceipt(jsonObject); } else if ("control".equals(messageType.toString())) { // Process control message handleControlMessage(jsonObject); } else { logArea.logMessage( "Unrecognised message type: " + messageType.toString() ); } } catch (ParseException e) { logArea.logMessage( "Error parsing JSON " + json ); } catch (Exception e) { logArea.logMessage( "Failed to process packet" ); } } }, new PacketTypeFilter(Message.class)); // Log all outgoing packets connection.addPacketInterceptor(new PacketInterceptor() { @Override public void interceptPacket(Packet packet) { logArea.logMessage( "Sent: " + packet.toXML()); } }, new PacketTypeFilter(Message.class)); connection.login(senderId + "@gcm.googleapis.com", apiKey); } //---------- support classes ---------- /** * XMPP Packet Extension for GCM Cloud Connection Server. */ private static class GcmPacketExtension extends DefaultPacketExtension { private final String json; public GcmPacketExtension(String json) { super( GCM_ELEMENT_NAME, GCM_NAMESPACE); this.json = json; } public String getJson() { return json; } @Override public String toXML() { return String.format("<%s xmlns=\"%s\">%s</%s>", GCM_ELEMENT_NAME, GCM_NAMESPACE, StringUtils.escapeForXML(json), GCM_ELEMENT_NAME); } public Packet toPacket() { Message message = new Message(); message.addExtension(this); return message; } } class LoggingConnectionListener implements ConnectionListener { @Override public void connected(XMPPConnection xmppConnection) { logArea.logMessage( "Connected." ); } @Override public void authenticated(XMPPConnection xmppConnection) { logArea.logMessage( "Authenticated." ); } @Override public void reconnectionSuccessful() { logArea.logMessage( "Reconnecting.." ); } @Override public void reconnectionFailed(Exception e) { logArea.logMessage( "Reconnection failed.. " + e.getMessage() ); } @Override public void reconnectingIn(int seconds) { logArea.logMessage( "Reconnecting in " + seconds + " secs" ); } @Override public void connectionClosedOnError(Exception e) { logArea.logMessage( "Connection closed on error." ); } @Override public void connectionClosed() { logArea.logMessage( "Connection closed." ); } } } // a non-editable combo (drop-down) box for destination addresses class DestComboBox extends JComboBox<String> { // (deleted to save space) } // screen panel for sending a message class SendMessagePanel extends JPanel implements ActionListener, ItemListener { // Message Types protected final int MSGTYPE_NOTIFICATION = 1; protected final int MSGTYPE_NOTIFICATION_DATA = 2; protected final int MSGTYPE_DATA_COLLAPSE = 3; protected final int MSGTYPE_DATA_NONCOLLAPSE = 4; // log window LogTextArea msgs; // server class CcsServer ccsServer; // constructor SendMessagePanel( UserList u, LogTextArea m, CcsServer c ) { // (deleted to save space) } // respond to the button @Override public void actionPerformed(ActionEvent e) { String toAddr = "zzzzzz"; // destination address // may be device, notification_key, or topic address ttl = 2419200; // time-to-live in seconds // what type of message? int msgTypeIndex = (--deleted--); // create the message Map<String, Object> message = new HashMap<String, Object>(); message.put("to", toAddr); if ( msgTypeIndex == MSGTYPE_NOTIFICATION || msgTypeIndex == MSGTYPE_NOTIFICATION_DATA || msgTypeIndex == MSGTYPE_DATA_COLLAPSE ) { // create a collapse key message.put("collapse_key", "ck"+msgTypeIndex ); } message.put("time_to_live", ttl); message.put("message_id", ccsServer.nextMessageId()); // notification included? if ( msgTypeIndex == MSGTYPE_NOTIFICATION || msgTypeIndex == MSGTYPE_NOTIFICATION_DATA ) { // create the notification payload HashMap<String, String> notePayload = new HashMap<>(); notePayload.put( "title", "Gcm Push Message Example" ); notePayload.put( "body", (--deleted--) ); // identify which notifications should replace older versions notePayload.put( "tag", "ntag" + msgTypeIndex ); notePayload.put( "icon", "@drawable/new_picture" ); // notification icon // additional stuff if we also have data if ( msgTypeIndex == MSGTYPE_NOTIFICATION_DATA ) { // what to do when the user opens the notification notePayload.put( "click_action", "OPEN_MAIN_ACTIVITY" ); } message.put( "notification", notePayload ); } // data included? if ( msgTypeIndex == MSGTYPE_NOTIFICATION_DATA || msgTypeIndex == MSGTYPE_DATA_COLLAPSE || msgTypeIndex == MSGTYPE_DATA_NONCOLLAPSE ) { HashMap<String, String> dataPayload = new HashMap<>(); dataPayload.put( "contents", (--deleted--) ); message.put("data", dataPayload); } // actually send the message try { ccsServer.sendDownstreamMessage( JSONValue.toJSONString(message) ); } catch (NotConnectedException enc ) { msgs.logMessage( "Not connected anymore, echo message is not sent: " + enc.getMessage() ); } } } class BorderPanel extends JPanel { // (--deleted--) } public class GcmPushServer { // (--deleted--) }
Google's example implementation of an XMPP server is in the friendly-ping sample. It has Java and Go versions.
