From 496732db3a54121d95a083e2f9d265a3fffbfff5 Mon Sep 17 00:00:00 2001
From: Michael Bayne <mdb@threerings.net>
Date: Wed, 17 Apr 2002 18:20:04 +0000
Subject: [PATCH] Automatically generate a failure response if an invocation
 provider method throws ServiceFailedException. The response for a service
 request named <foo> would be <foo>Failed. The response has a single argument
 which is the reason string provided by the ServiceFailedException. We were
 doing this by hand all over the place, and now it will be handled
 automatically. Yay!

git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@1268 542714f4-19e9-0310-aa3c-eee0fc999fb1
---
 .../presents/server/InvocationManager.java    | 35 ++++++++++++++++---
 .../presents/server/InvocationProvider.java   | 19 +++++++++-
 2 files changed, 49 insertions(+), 5 deletions(-)

diff --git a/src/java/com/threerings/presents/server/InvocationManager.java b/src/java/com/threerings/presents/server/InvocationManager.java
index 91d634cd8..478b8e8cf 100644
--- a/src/java/com/threerings/presents/server/InvocationManager.java
+++ b/src/java/com/threerings/presents/server/InvocationManager.java
@@ -1,14 +1,18 @@
 //
-// $Id: InvocationManager.java,v 1.10 2001/10/24 00:36:40 mdb Exp $
+// $Id: InvocationManager.java,v 1.11 2002/04/17 18:20:04 mdb Exp $
 
 package com.threerings.presents.server;
 
+import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.util.HashMap;
 
+import com.samskivert.util.StringUtil;
+
 import com.threerings.presents.Log;
 import com.threerings.presents.dobj.*;
-import com.threerings.presents.data.*;
+import com.threerings.presents.data.ClientObject;
+import com.threerings.presents.data.InvocationObject;
 import com.threerings.presents.util.ClassUtil;
 
 /**
@@ -132,14 +136,16 @@ public class InvocationManager
         // prune the method arguments from the full message arguments
         Object[] margs = new Object[args.length-1];
         int cloid = event.getSourceOid();
-        margs[0] = PresentsServer.omgr.getObject(cloid);
+        ClientObject source = (ClientObject)
+            PresentsServer.omgr.getObject(cloid);
         // make sure the client is still around
-        if (margs[0] == null) {
+        if (source == null) {
             Log.warning("Client no longer around for invocation provider " +
                         "request [module=" + module +
                         ", proc=" + procedure + ", cloid=" + cloid + "].");
             return;
         }
+        margs[0] = source;
         System.arraycopy(args, 2, margs, 1, args.length-2);
 
         // look up the method that will handle this procedure
@@ -155,6 +161,23 @@ public class InvocationManager
         // and invoke it
         try {
             procmeth.invoke(provider, margs);
+
+        } catch (InvocationTargetException ite) {
+            Throwable te = ite.getTargetException();
+            if (te instanceof ServiceFailedException) {
+                // automatically generate a <foo>Failed response
+                provider.sendResponse(source, invid.intValue(),
+                                      procedure + FAILED_SUFFIX,
+                                      te.getMessage());
+
+            } else {
+                Log.warning("Invocation procedure failed " +
+                            "[provider=" + provider +
+                            ", method=" + procmeth +
+                            ", args=" + StringUtil.toString(margs) + "].");
+                Log.logStackTrace(te);
+            }
+
         } catch (Exception e) {
             Log.warning("Error invoking invocation procedure " +
                         "[provider=" + provider +
@@ -167,4 +190,8 @@ public class InvocationManager
     protected int _invoid;
     protected HashMap _providers = new HashMap();
     protected HashMap _methcache = new HashMap();
+
+    /** The text that is appended to the procedure name when automatically
+     * generating a failure response. */
+    protected static final String FAILED_SUFFIX = "Failed";
 }
diff --git a/src/java/com/threerings/presents/server/InvocationProvider.java b/src/java/com/threerings/presents/server/InvocationProvider.java
index 4c6cf0cf8..dcbc7e736 100644
--- a/src/java/com/threerings/presents/server/InvocationProvider.java
+++ b/src/java/com/threerings/presents/server/InvocationProvider.java
@@ -1,5 +1,5 @@
 //
-// $Id: InvocationProvider.java,v 1.6 2001/10/11 04:07:53 mdb Exp $
+// $Id: InvocationProvider.java,v 1.7 2002/04/17 18:20:04 mdb Exp $
 
 package com.threerings.presents.server;
 
@@ -53,6 +53,23 @@ import com.threerings.presents.dobj.MessageEvent;
  * the reflection rules for automatic conversion of primitive types
  * (supply an <code>Integer</code> object for <code>int</code> params,
  * etc.).
+ *
+ * <p> Note that if an invocation service method throws a {@link
+ * ServiceFailedException}, the invocation manager will automatically
+ * issue a response to the client with the string <code>Failed</code>
+ * appended to the request method. For example, if the client issues a
+ * request for <code>Foo</code> which results in a call to
+ * <code>handleFooRequest</code>, which throws a service failed exception,
+ * the server will automatically issue a failure response named
+ * <code>FooFailed</code> with the single argument being the
+ * <code>reason</code> string provided to the constructor of the service
+ * failed exception. The caller would then implement:
+ *
+ * <pre>
+ * public void handleFooFailed (int invid, String reason)
+ * </pre>
+ *
+ * to handle the failure.
  */
 public class InvocationProvider
 {