Support HTTPD graceful restarts for non-stop operation. Simplified Python and Java error capture and recovery.

git-svn-id: http://svn.us.apache.org/repos/asf/tuscany@907470 13f79535-47bb-0310-9956-ffa450edef68

9 files changed, 68 insertions, 199 deletions

diff --git a/sca-cpp/trunk/modules/java/eval.hpp b/sca-cpp/trunk/modules/java/eval.hpp
index e10ec29a0b..9140fe75b4 100644
--- a/sca-cpp/trunk/modules/java/eval.hpp
+++ b/sca-cpp/trunk/modules/java/eval.hpp
@@ -29,13 +29,12 @@
 
 #include "list.hpp"
 #include "value.hpp"
-#include "io.hpp"
 
 namespace tuscany {
 namespace java {
 
 /**
- * Initialize a JVM.
+ * Represent a Java VM runtime.
  */
 jobject JNICALL nativeInvoke(JNIEnv *env, jobject self, jobject proxy, jobject method, jobjectArray args);
 
@@ -87,9 +86,6 @@ public:
             jvm->GetEnv((void**)&env, JNI_VERSION_1_6);
         }
 
-        // Capture JVM standard IO
-        setupIO();
-
         // Lookup System classes and methods
         classClass = env->FindClass("java/lang/Class");
         methodClass = env->FindClass("java/lang/reflect/Method");
@@ -114,6 +110,7 @@ public:
         loaderForName = env->GetStaticMethodID(loaderClass, "forName", "(Ljava/lang/String;ZLjava/lang/ClassLoader;)Ljava/lang/Class;");
         invokerClass = env->FindClass("org/apache/tuscany/InvocationHandler");
         invokerValueOf = env->GetStaticMethodID(invokerClass, "valueOf", "(Ljava/lang/Class;J)Ljava/lang/Object;");
+        invokerStackTrace = env->GetStaticMethodID(invokerClass, "stackTrace", "(Ljava/lang/Throwable;)Ljava/lang/String;");
         invokerLambda = env->GetFieldID(invokerClass, "lambda", "J");
         iterableUtilClass = env->FindClass("org/apache/tuscany/IterableUtil");
         iterableValueOf = env->GetStaticMethodID(iterableUtilClass, "list", "([Ljava/lang/Object;)Ljava/lang/Iterable;");
@@ -127,7 +124,6 @@ public:
         nm.signature = const_cast<char*>("(Ljava/lang/Object;Ljava/lang/reflect/Method;[Ljava/lang/Object;)Ljava/lang/Object;");
         nm.fnPtr = (void*)nativeInvoke;
         env->RegisterNatives(invokerClass, &nm, 1);
-
     }
 
     JavaVM* jvm;
@@ -154,13 +150,13 @@ public:
     jmethodID loaderForName;
     jclass invokerClass;
     jmethodID invokerValueOf;
+    jmethodID invokerStackTrace;
     jfieldID invokerLambda;
     jclass iterableUtilClass;
     jmethodID iterableValueOf;
     jmethodID iterableCar;
     jmethodID iterableCdr;
     jmethodID iterableIsNil;
-
 };
 
 /**
@@ -169,9 +165,13 @@ public:
 string lastException(const JavaRuntime& jr) {
     if (!jr.env->ExceptionCheck())
         return "No Exception";
-    jr.env->ExceptionDescribe();
+    const jthrowable ex = jr.env->ExceptionOccurred();
+    const jstring trace = (jstring)jr.env->CallStaticObjectMethod(jr.invokerClass, jr.invokerStackTrace, ex);
+    const char* c = jr.env->GetStringUTFChars(trace, NULL);
+    const string msg(c);
+    jr.env->ReleaseStringUTFChars(trace, c);
     jr.env->ExceptionClear();
-    return "UnknownException";
+    return msg;
 }
 
 /**
diff --git a/sca-cpp/trunk/modules/java/io.hpp b/sca-cpp/trunk/modules/java/io.hpp
deleted file mode 100644
index 58ca58f0b2..0000000000
--- a/sca-cpp/trunk/modules/java/io.hpp
+++ /dev/null
@@ -1,43 +0,0 @@
-/*
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF licenses this file
- * to you 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.
- */
-
-/* $Rev$ $Date$ */
-
-#ifndef tuscany_java_io_hpp
-#define tuscany_java_io_hpp
-
-/**
- * Java IO functions.
- */
-#include "stream.hpp"
-#include "../scheme/io.hpp"
-
-namespace tuscany {
-namespace java {
-
-/**
- * Setup the display and log hooks.
- */
-bool setupIO() {
-    return true;
-}
-
-}
-}
-#endif /* tuscany_python_pyio_hpp */
diff --git a/sca-cpp/trunk/modules/java/mod-java.cpp b/sca-cpp/trunk/modules/java/mod-java.cpp
index b8ac642c0e..4b8e7dca56 100644
--- a/sca-cpp/trunk/modules/java/mod-java.cpp
+++ b/sca-cpp/trunk/modules/java/mod-java.cpp
@@ -55,7 +55,9 @@ const failable<bool> stop(unused ServerConf& sc) {
 /**
  * Restart the module.
  */
-const failable<bool> restart(unused ServerConf& sc) {
+const failable<bool> restart(ServerConf& sc) {
+    // Start a Java runtime
+    sc.moduleConf =  new (gc_new<java::JavaRuntime>()) java::JavaRuntime();
     return true;
 }
 
diff --git a/sca-cpp/trunk/modules/java/org/apache/tuscany/InvocationHandler.java b/sca-cpp/trunk/modules/java/org/apache/tuscany/InvocationHandler.java
index 5707a07bc7..c5ec6005a1 100644
--- a/sca-cpp/trunk/modules/java/org/apache/tuscany/InvocationHandler.java
+++ b/sca-cpp/trunk/modules/java/org/apache/tuscany/InvocationHandler.java
@@ -19,6 +19,8 @@
 
 package org.apache.tuscany;
 
+import java.io.PrintWriter;
+import java.io.StringWriter;
 import java.lang.reflect.Method;
 import java.lang.reflect.Proxy;
 
@@ -40,7 +42,19 @@ class InvocationHandler implements java.lang.reflect.InvocationHandler {
         return Proxy.newProxyInstance(iface.getClassLoader(), new Class[]{iface}, new InvocationHandler(lambda));
     }
 
+    /**
+     * Proxy invocation of a C++ function.
+     */
     @Override
     public native Object invoke(final Object proxy, final Method method, final Object[] args) throws Throwable;
 
+    /**
+     * Return the stack trace of an exception.
+     */
+    static String stackTrace(final Throwable e) {
+        final StringWriter sw = new StringWriter();
+        final PrintWriter pw = new PrintWriter(sw);
+        e.printStackTrace(pw);
+        return sw.toString();
+    }
 }
diff --git a/sca-cpp/trunk/modules/python/eval.hpp b/sca-cpp/trunk/modules/python/eval.hpp
index 09c2cba92d..5231b0ef60 100644
--- a/sca-cpp/trunk/modules/python/eval.hpp
+++ b/sca-cpp/trunk/modules/python/eval.hpp
@@ -29,33 +29,52 @@
 
 #include "list.hpp"
 #include "value.hpp"
-#include "io.hpp"
 
 namespace tuscany {
 namespace python {
 
 /**
- * Initialize the Python runtime.
+ * Represent a Python runtime.
  */
 class PythonRuntime {
 public:
-    PythonRuntime() : owner(true) {
+    PythonRuntime() {
+        if (Py_IsInitialized())
+            return;
         Py_InitializeEx(0);
-        setupIO();
-    }
-
-    PythonRuntime(unused const PythonRuntime& r) : owner(false) {
     }
+};
 
-    ~PythonRuntime() {
-        if (!owner)
-            return;
-        //Py_Finalize();
+/**
+ * Return the last python error.
+ */
+const string lastError() {
+    if(PyErr_Occurred()) {
+        PyObject* type;
+        PyObject* val;
+        PyObject* trace;
+        PyErr_Fetch(&type, &val, &trace);
+        if (type != NULL && val != NULL) {
+            PyObject* stype = PyObject_Str(type);    
+            PyObject* sval = PyObject_Str(val);    
+            string msg = string() + PyString_AsString(stype) + " : " + PyString_AsString(sval);
+            Py_DECREF(stype);
+            Py_DECREF(sval);                                    
+            Py_DECREF(type);
+            Py_DECREF(val);
+            Py_XDECREF(trace);
+            PyErr_Print();
+            return msg;
+        }
+        PyErr_Print();
+        Py_XDECREF(type);
+        Py_XDECREF(val);
+        Py_XDECREF(trace);
+        PyErr_Print();
+        return "Unknown Python error";
     }
-
-private:
-    const bool owner;
-};
+    return "";
+}
 
 /**
  * Declare conversion functions.
@@ -222,8 +241,10 @@ const failable<value> evalScript(const value& expr, PyObject* script) {
 
         // The start, stop, and restart functions are optional
         const value fn = car<value>(expr);
-        if (fn == "start" || fn == "stop" || fn == "restart")
+        if (fn == "start" || fn == "stop" || fn == "restart") {
+            PyErr_Clear();
             return value(false);
+        }
 
         return mkfailure<value>(string("Couldn't find function: ") + car<value>(expr) + " : " + lastError());
     }
diff --git a/sca-cpp/trunk/modules/python/io.hpp b/sca-cpp/trunk/modules/python/io.hpp
deleted file mode 100644
index 10119a4f77..0000000000
--- a/sca-cpp/trunk/modules/python/io.hpp
+++ /dev/null
@@ -1,127 +0,0 @@
-/*
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF licenses this file
- * to you 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.
- */
-
-/* $Rev$ $Date$ */
-
-#ifndef tuscany_python_io_hpp
-#define tuscany_python_io_hpp
-
-/**
- * Hooks used to capture python stdout and stderr.
- */
-#include <python2.6/Python.h>
-
-#include "stream.hpp"
-#include "../scheme/io.hpp"
-
-namespace tuscany {
-namespace python {
-
-/**
- * Hook method used to redirect python output to a stream.
- */
-PyObject* display(unused PyObject* self, PyObject* args) {
-    char* s = NULL;
-    if (!PyArg_ParseTuple(args, "s", &s))
-        return NULL;
-
-    scheme::displayStream() << s;
-
-    Py_INCREF(Py_None);
-    return Py_None;
-}
-
-PyMethodDef displayHookMethods[] = {
-        {"display", display, METH_VARARGS, "Redirects stdout"},
-        {NULL, NULL, 0, NULL}};
-
-/**
- * Hook method used to redirect python errors to a stream.
- */
-PyObject* log(unused PyObject* self, PyObject* args) {
-    char* s = NULL;
-    if (!PyArg_ParseTuple(args, "s", &s))
-        return NULL;
-
-    scheme::logStream() << s;
-
-    Py_INCREF(Py_None);
-    return Py_None;
-}
-
-PyMethodDef logHookMethods[] = {
-        {"log", log, METH_VARARGS, "Redirects stdout"},
-        {NULL, NULL, 0, NULL}};
-
-/**
- * Setup the display and log hooks.
- */
-bool setupIO() {
-    Py_InitModule("displayhook", displayHookMethods);
-    PyRun_SimpleString(
-            "import sys\n"
-            "import displayhook\n"
-            "\n"
-            "class DisplayHook:\n"
-            "    def write(self, text):\n"
-            "        displayhook.display(text)\n"
-            "\n"
-            "sys.stdout = DisplayHook()\n");
-
-    Py_InitModule("loghook", logHookMethods);
-    PyRun_SimpleString(
-            "import sys\n"
-            "import loghook\n"
-            "\n"
-            "class LogHook:\n"
-            "    def write(self, text):\n"
-            "        loghook.log(text)\n"
-            "\n"
-            "sys.stderr = LogHook()\n");
-    return true;
-}
-
-/**
- * Return the last python error.
- */
-const string lastError() {
-    ostream* pos = scheme::logOutStream;
-    ostringstream eos;
-    scheme::logOutStream = &eos;
-    if (PyErr_Occurred())
-        PyErr_Print();
-    scheme::logOutStream = pos;
-    return str(eos);
-}
-
-/**
- * Read and write values (using the scheme representation as it's the canonical
- * representation used throughout the runtime.)
- */
-const value readValue(istream& in) {
-    return scheme::readValue(in);
-}
-
-const bool writeValue(const value& val, ostream& out) {
-    return scheme::writeValue(val, out);
-}
-
-}
-}
-#endif /* tuscany_python_io_hpp */
diff --git a/sca-cpp/trunk/modules/python/mod-python.cpp b/sca-cpp/trunk/modules/python/mod-python.cpp
index a45b83997f..df94f2e8a1 100644
--- a/sca-cpp/trunk/modules/python/mod-python.cpp
+++ b/sca-cpp/trunk/modules/python/mod-python.cpp
@@ -56,6 +56,8 @@ const failable<bool> stop(unused ServerConf& sc) {
  * Restart the module.
  */
 const failable<bool> restart(unused ServerConf& sc) {
+    // Start a Python runtime
+    sc.moduleConf =  new (gc_new<python::PythonRuntime>()) python::PythonRuntime();
     return true;
 }
 
diff --git a/sca-cpp/trunk/modules/server/client-test.hpp b/sca-cpp/trunk/modules/server/client-test.hpp
index 0f8b64a031..651a9016b2 100644
--- a/sca-cpp/trunk/modules/server/client-test.hpp
+++ b/sca-cpp/trunk/modules/server/client-test.hpp
@@ -312,7 +312,7 @@ const bool testPut() {
             + (list<value>() + "price" + string("$2.99"));
     const list<value> a = mklist<value>(string("item"), string("cart-53d67a61-aa5e-4e5e-8401-39edeba8b83b"), i);
     http::CURLSession ch;
-    value rc = content(http::put(a, testURI, ch));
+    value rc = content(http::put(a, testURI + "/111", ch));
     assert(rc == value(true));
     return true;
 }
@@ -320,7 +320,7 @@ const bool testPut() {
 const bool testDel() {
     gc_scoped_pool pool;
     http::CURLSession ch;
-    value rc = content(http::del(testURI, ch));
+    value rc = content(http::del(testURI + "/111", ch));
     assert(rc == value(true));
     return true;
 }
diff --git a/sca-cpp/trunk/modules/server/mod-eval.hpp b/sca-cpp/trunk/modules/server/mod-eval.hpp
index 0e68e63016..6ab1d68ad6 100644
--- a/sca-cpp/trunk/modules/server/mod-eval.hpp
+++ b/sca-cpp/trunk/modules/server/mod-eval.hpp
@@ -395,7 +395,7 @@ const failable<bool> confComponents(const string& lifecycle, ServerConf& sc, ser
     debug(sc.implementations, "modeval::confComponents::implementations");
 
     // Start or restart the component implementations
-    return applyLifecycleExpr(impls, mklist<value>(lifecycle));
+    return applyLifecycleExpr(impls, mklist<value>(c_str(lifecycle)));
 }
 
 /**