ftp: Add LoginCellProvider for FTP

Adding a dedicating FTP provider for LoginCellFactory
allows the shared executor to be bound to the lifetime
of the LoginManager.

Target: trunk
Require-notes: no
Require-book: no
Acked-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Patch: http://rb.dcache.org/r/6310/

modules/dcache-ftp/src/main/java/diskCacheV111/doors/LineBasedDoor.java

@@ -15,7 +15,6 @@
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
 
 import dmg.cells.nucleus.CDC;
 import dmg.cells.nucleus.CellCommandListener;
@@ -27,7 +26,6 @@
 import dmg.util.StreamEngine;
 
 import org.dcache.cells.AbstractCell;
-import org.dcache.cells.Option;
 import org.dcache.util.FireAndForgetTask;
 import org.dcache.util.Transfer;
 
@@ -45,17 +43,14 @@ public class LineBasedDoor
 {
     private static final Logger LOGGER = LoggerFactory.getLogger(LineBasedDoor.class);
 
-    @Option(name = "interpreter",
-            description = "Protocol interpreter",
-            required = true)
-    protected Class<LineBasedInterpreter> interpreterClass;
+    private final Class<? extends LineBasedInterpreter> interpreterClass;
 
     /**
      * Door instances are created by the LoginManager. This is the
      * stream engine passed to us from the LoginManager upon
      * instantiation.
      */
-    private StreamEngine engine;
+    private final StreamEngine engine;
 
     private LineBasedInterpreter interpreter;
 
@@ -64,22 +59,21 @@ public class LineBasedDoor
 
     /**
      * Shared executor for processing commands.
-     *
-     * FIXME: This will be created within the thread group creating
-     * the first door. This will usually be the login manager and
-     * works fine, but it isn't clean.
      */
-    private static final ExecutorService EXECUTOR =
-        Executors.newCachedThreadPool();
+    private final ExecutorService executor;
 
     private Thread workerThread;
 
-    public LineBasedDoor(String name, StreamEngine engine, Args args)
+    public LineBasedDoor(String cellName, Args args, Class<? extends LineBasedInterpreter> interpreterClass,
+                         StreamEngine engine, ExecutorService executor)
     {
-        super(name, args);
+        super(cellName, args);
+
+        this.interpreterClass = interpreterClass;
+        this.engine = engine;
+        this.executor = executor;
 
         try {
-            this.engine = engine;
             doInit();
             workerThread.start();
         } catch (InterruptedException e) {
@@ -285,7 +279,7 @@ public synchronized void add(String command)
                 if (!isRunning) {
                     final CDC cdc = new CDC();
                     isRunning = true;
-                    EXECUTOR.submit(new FireAndForgetTask(new Runnable()
+                    executor.submit(new FireAndForgetTask(new Runnable()
                     {
                         @Override
                         public void run()

modules/dcache-ftp/src/main/java/diskCacheV111/doors/LineBasedDoorFactory.java

@@ -0,0 +1,55 @@
+package diskCacheV111.doors;
+
+import com.google.common.util.concurrent.AbstractService;
+
+import java.lang.reflect.InvocationTargetException;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+
+import dmg.cells.nucleus.Cell;
+import dmg.cells.services.login.LoginCellFactory;
+import dmg.util.Args;
+import dmg.util.StreamEngine;
+
+import static diskCacheV111.doors.LineBasedDoor.LineBasedInterpreter;
+
+public class LineBasedDoorFactory extends AbstractService implements LoginCellFactory
+{
+    private final Class<? extends LineBasedInterpreter> interpreter;
+    private final String cellName;
+    private final Args args;
+    private ExecutorService executor;
+
+    public LineBasedDoorFactory(Class<? extends LineBasedInterpreter> interpreter, Args args, String parentCellName)
+    {
+        this.interpreter = interpreter;
+        this.cellName = parentCellName + "*";
+        this.args = args;
+    }
+
+    @Override
+    public String getName()
+    {
+        return interpreter.getSimpleName();
+    }
+
+    @Override
+    public Cell newCell(StreamEngine engine, String userName) throws InvocationTargetException
+    {
+        return new LineBasedDoor(cellName, args, interpreter, engine, executor);
+    }
+
+    @Override
+    protected void doStart()
+    {
+        this.executor = Executors.newCachedThreadPool();
+        notifyStarted();
+    }
+
+    @Override
+    protected void doStop()
+    {
+        executor.shutdown();
+        notifyStopped();
+    }
+}

modules/dcache-ftp/src/main/java/diskCacheV111/doors/LineBasedDoorProvider.java

@@ -0,0 +1,35 @@
+package diskCacheV111.doors;
+
+import dmg.cells.services.login.LoginCellFactory;
+import dmg.cells.services.login.LoginCellProvider;
+import dmg.util.Args;
+
+import static diskCacheV111.doors.LineBasedDoor.LineBasedInterpreter;
+
+public class LineBasedDoorProvider implements LoginCellProvider
+{
+    @Override
+    public int getPriority(String name)
+    {
+        try {
+            if (LineBasedInterpreter.class.isAssignableFrom(Class.forName(name))) {
+                return 100;
+            }
+        } catch (ClassNotFoundException ignored) {
+        }
+        return Integer.MIN_VALUE;
+    }
+
+    @Override
+    public LoginCellFactory createFactory(String name, Args args, String parentCellName) throws IllegalArgumentException
+    {
+        try {
+            Class<?> interpreter = Class.forName(name);
+            if (LineBasedInterpreter.class.isAssignableFrom(interpreter)) {
+                return new LineBasedDoorFactory(interpreter.asSubclass(LineBasedInterpreter.class), args, parentCellName);
+            }
+        } catch (ClassNotFoundException ignored) {
+        }
+        throw new IllegalArgumentException();
+    }
+}

modules/dcache-ftp/src/main/resources/META-INF/services/dmg.cells.services.login.LoginCellProvider

@@ -0,0 +1 @@
+diskCacheV111.doors.LineBasedDoorProvider

skel/share/services/ftp.batch

@@ -49,8 +49,7 @@ check ftp.mover.queue
 exec file:${dcache.paths.share}/cells/stage.fragment ftp doors
 
 create dmg.cells.services.login.LoginManager ${ftp.cell.name} \
-  "${ftp.net.port} diskCacheV111.doors.LineBasedDoor \
-   -interpreter=${ftp.implementation} \
+  "${ftp.net.port} ${ftp.implementation} \
    -listen=${ftp.net.listen} \
    -prot=raw \
    -export=${ftp.cell.export} \