Experimental NOTIFY support (RFC 5465)

FAQ.md

@@ -2819,7 +2819,9 @@ Reformatting and displaying such messages will take too long. You can try to use
 <a name="faq125"></a>
 **(125) What are the current experimental features?**
 
-* ...
+* [IMAP NOTIFY](https://tools.ietf.org/html/rfc5465) support
+
+NOTIFY support means that notifications of *subscribed* folders will be requested and when a notification is received that the folder will be synchronized.
 
 <br />
 

app/build.gradle

@@ -1,7 +1,7 @@
 apply plugin: 'com.android.application'
 apply plugin: 'com.bugsnag.android.gradle'
 
-def getVersionCode = { -> return 1412 }
+def getVersionCode = { -> return 1413 }
 def getReleaseName = { -> return "\"Bambiraptor\"" }
 // https://en.wikipedia.org/wiki/List_of_dinosaur_genera
 

app/src/main/java/com/sun/mail/imap/IMAPFolder.java

@@ -3627,7 +3627,14 @@ public class IMAPFolder extends Folder implements UIDFolder, ResponseHandler {
 	} else if (ir.keyEquals("RECENT")) {
 	    // update 'recent'
 	    recent = ir.getNumber();
-	}
+	} else if (ir.keyEquals("STATUS"))
+		try {
+			String mailbox = ir.readAtomString();
+			Folder f = store.getFolder(mailbox);
+			notifyFolderChangeListeners(f);
+		} catch (Throwable ex) {
+			eu.faircode.email.Log.e(ex);
+		}
     }
 
     /**

app/src/main/java/eu/faircode/email/ApplicationEx.java

@@ -388,6 +388,8 @@ public class ApplicationEx extends Application implements SharedPreferences.OnSh
             editor.remove("tcp_keep_alive");
         else if (version < 1407)
             editor.remove("print_html_confirmed");
+        else if (version < 1413)
+            editor.remove("experiments");
 
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O && !BuildConfig.DEBUG)
             editor.remove("background_service");

app/src/main/java/eu/faircode/email/ServiceSynchronize.java

@@ -49,8 +49,13 @@ import androidx.lifecycle.MutableLiveData;
 import androidx.lifecycle.Observer;
 import androidx.preference.PreferenceManager;
 
+import com.sun.mail.iap.Argument;
+import com.sun.mail.iap.ProtocolException;
+import com.sun.mail.iap.Response;
 import com.sun.mail.imap.IMAPFolder;
 import com.sun.mail.imap.IMAPStore;
+import com.sun.mail.imap.protocol.IMAPProtocol;
+import com.sun.mail.imap.protocol.IMAPResponse;
 
 import java.text.DateFormat;
 import java.util.ArrayList;
@@ -139,7 +144,7 @@ public class ServiceSynchronize extends ServiceBase implements SharedPreferences
             "sync_shared_folders",
             "prefer_ip4", "tcp_keep_alive", "ssl_harden", // force reconnect
             "badge", "unseen_ignored", // force update badge/widget
-            "protocol", "debug", // force reconnect
+            "experiments", "debug", "protocol", // force reconnect
             "auth_plain",
             "auth_login",
             "auth_sasl"
@@ -944,6 +949,7 @@ public class ServiceSynchronize extends ServiceBase implements SharedPreferences
 
                 // Debug
                 SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
+                boolean experiments = prefs.getBoolean("experiments", false);
                 boolean debug = (prefs.getBoolean("debug", false) || BuildConfig.DEBUG);
 
                 final EmailService iservice = new EmailService(
@@ -1035,6 +1041,8 @@ public class ServiceSynchronize extends ServiceBase implements SharedPreferences
                     if (!capIdle || account.poll_interval < OPTIMIZE_KEEP_ALIVE_INTERVAL)
                         optimizeAccount(account, "IDLE");
 
+                    final boolean capNotify = (experiments && iservice.hasCapability("NOTIFY"));
+
                     db.account().setAccountState(account.id, "connected");
                     db.account().setAccountError(account.id, null);
                     db.account().setAccountWarning(account.id, null);
@@ -1096,6 +1104,21 @@ public class ServiceSynchronize extends ServiceBase implements SharedPreferences
                                 wlFolder.release();
                             }
                         }
+
+                        @Override
+                        public void folderChanged(FolderEvent e) {
+                            try {
+                                wlFolder.acquire();
+
+                                String name = e.getFolder().getFullName();
+                                EntityLog.log(ServiceSynchronize.this, "Folder changed=" + name);
+                                EntityFolder folder = db.folder().getFolderByName(account.id, name);
+                                if (folder != null)
+                                    EntityOperation.sync(ServiceSynchronize.this, folder.id, false);
+                            } finally {
+                                wlFolder.release();
+                            }
+                        }
                     });
 
                     // Update folder list
@@ -1290,6 +1313,40 @@ public class ServiceSynchronize extends ServiceBase implements SharedPreferences
 
                             if (sync && folder.selectable)
                                 EntityOperation.sync(this, folder.id, false);
+
+                            if (capNotify && EntityFolder.INBOX.equals(folder.type))
+                                ifolder.doCommand(new IMAPFolder.ProtocolCommand() {
+                                    @Override
+                                    public Object doCommand(IMAPProtocol protocol) throws ProtocolException {
+                                        EntityLog.log(ServiceSynchronize.this, account.name + " NOTIFY enable");
+
+                                        // https://tools.ietf.org/html/rfc5465
+                                        Argument arg = new Argument();
+                                        arg.writeAtom("SET STATUS (subscribed (MessageNew MessageExpunge FlagChange))");
+
+                                        Response[] responses = protocol.command("NOTIFY", arg);
+
+                                        if (responses.length == 0)
+                                            throw new ProtocolException("No response");
+                                        if (!responses[responses.length - 1].isOK())
+                                            throw new ProtocolException(responses[responses.length - 1]);
+
+                                        for (int i = 0; i < responses.length - 1; i++) {
+                                            EntityLog.log(ServiceSynchronize.this, account.name + " " + responses[i]);
+                                            if (responses[i] instanceof IMAPResponse) {
+                                                IMAPResponse ir = (IMAPResponse) responses[i];
+                                                if (ir.keyEquals("STATUS")) {
+                                                    String mailbox = ir.readAtomString();
+                                                    EntityFolder f = db.folder().getFolderByName(account.id, mailbox);
+                                                    if (f != null)
+                                                        EntityOperation.sync(ServiceSynchronize.this, f.id, false);
+                                                }
+                                            }
+                                        }
+
+                                        return null;
+                                    }
+                                });
                         } else {
                             mapFolders.put(folder, null);
                             db.folder().setFolderState(folder.id, null);

app/src/main/java/javax/mail/Folder.java

@@ -1469,6 +1469,10 @@ public abstract class Folder implements AutoCloseable {
 	store.notifyFolderRenamedListeners(this, folder);
     }
 
+    protected void notifyFolderChangeListeners(Folder folder) {
+        store.notifyFolderListeners(FolderEvent.CHANGED, folder);
+    }
+
     // Vector of MessageCount listeners
     private volatile Vector<MessageCountListener> messageCountListeners = null;
 

app/src/main/java/javax/mail/event/FolderEvent.java

@@ -46,6 +46,8 @@ public class FolderEvent extends MailEvent {
     /** The folder was renamed. */
     public static final int RENAMED 		= 3;
 
+    public static final int CHANGED 		= 4;
+
     /**
      * The event type.
      *
@@ -140,5 +142,7 @@ public class FolderEvent extends MailEvent {
 	    ((FolderListener)listener).folderDeleted(this);
 	else if (type == RENAMED)
 	    ((FolderListener)listener).folderRenamed(this);
+    else if (type == CHANGED)
+        ((FolderListener)listener).folderChanged(this);
     }
 }

app/src/main/java/javax/mail/event/FolderListener.java

@@ -45,4 +45,6 @@ public interface FolderListener extends java.util.EventListener {
      * @param	e	the FolderEvent
      */
     public void folderRenamed(FolderEvent e);
+
+    public void folderChanged(FolderEvent e);
 }