initial commit

modpythonhandler.py

@@ -0,0 +1,225 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+"""
+This file is part of the web2py Web Framework
+Copyrighted by Massimo Di Pierro <mdipierro@cs.depaul.edu>
+License: LGPLv3 (http://www.gnu.org/licenses/lgpl.html)
+
+WSGI wrapper for mod_python. Requires Python 2.2 or greater.
+Part of CherryPy mut modified by Massimo Di Pierro (2008) for web2py
+
+<Location /myapp>
+    SetHandler python-program
+    PythonHandler modpythonhandler
+    PythonPath \"['/path/to/web2py/'] + sys.path\"
+    PythonOption SCRIPT_NAME /myapp
+</Location>
+
+Some WSGI implementations assume that the SCRIPT_NAME environ variable will
+always be equal to 'the root URL of the app'; Apache probably won't act as
+you expect in that case. You can add another PythonOption directive to tell
+modpython_gateway to force that behavior:
+
+    PythonOption SCRIPT_NAME /mcontrol
+
+The module.function will be called with no arguments on server shutdown,
+once for each child process or thread.
+"""
+
+import traceback
+import sys
+import os
+from mod_python import apache
+
+path = os.path.dirname(os.path.abspath(__file__))
+os.chdir(path)
+sys.path = [path]+[p for p in sys.path if not p==path]
+
+import gluon.main
+
+
+class InputWrapper(object):
+    """ Input wrapper for the wsgi handler  """
+
+    def __init__(self, req):
+        """ InputWrapper constructor  """
+
+        self.req = req
+
+    def close(self):
+        """ """
+
+        pass
+
+    def read(self, size=-1):
+        """ Wrapper for req.read  """
+
+        return self.req.read(size)
+
+    def readline(self, size=-1):
+        """ Wrapper for req.readline  """
+
+        return self.req.readline(size)
+
+    def readlines(self, hint=-1):
+        """ Wrapper for req.readlines  """
+
+        return self.req.readlines(hint)
+
+    def __iter__(self):
+        """ Defines a generator with the req data  """
+
+        line = self.readline()
+        while line:
+            yield line
+
+            # Notice this won't prefetch the next line; it only
+            # gets called if the generator is resumed.
+            line = self.readline()
+
+
+class ErrorWrapper(object):
+    """ Error wrapper for the wsgi handler  """
+
+    def __init__(self, req):
+        """ ErrorWrapper constructor """
+
+        self.req = req
+
+    def flush(self):
+        """   """
+
+        pass
+
+    def write(self, msg):
+        """ Logs the given msg in the log file """
+
+        self.req.log_error(msg)
+
+    def writelines(self, seq):
+        """ Writes various lines in the log file """
+
+        self.write(''.join(seq))
+
+
+bad_value = "You must provide a PythonOption '%s', either 'on' or 'off', when running a version of mod_python < 3.1"
+
+
+class Handler:
+    """ Defines the handler  """
+
+    def __init__(self, req):
+        """ Handler constructor  """
+
+        self.started = False
+        options = req.get_options()
+
+        # Threading and forking
+        try:
+            q = apache.mpm_query
+            threaded = q(apache.AP_MPMQ_IS_THREADED)
+            forked = q(apache.AP_MPMQ_IS_FORKED)
+        except AttributeError:
+            threaded = options.get('multithread', '').lower()
+
+            if threaded == 'on':
+                threaded = True
+            elif threaded == 'off':
+                threaded = False
+            else:
+                raise ValueError(bad_value % 'multithread')
+
+            forked = options.get('multiprocess', '').lower()
+
+            if forked == 'on':
+                forked = True
+            elif forked == 'off':
+                forked = False
+            else:
+                raise ValueError(bad_value % 'multiprocess')
+
+        env = self.environ = dict(apache.build_cgi_env(req))
+
+        if 'SCRIPT_NAME' in options:
+            # Override SCRIPT_NAME and PATH_INFO if requested.
+            env['SCRIPT_NAME'] = options['SCRIPT_NAME']
+            env['PATH_INFO'] = req.uri[len(options['SCRIPT_NAME']):]
+
+        env['wsgi.input'] = InputWrapper(req)
+        env['wsgi.errors'] = ErrorWrapper(req)
+        env['wsgi.version'] = (1, 0)
+        env['wsgi.run_once'] = False
+
+        if env.get('HTTPS') in ('yes', 'on', '1'):
+            env['wsgi.url_scheme'] = 'https'
+        else:
+            env['wsgi.url_scheme'] = 'http'
+
+        env['wsgi.multithread'] = threaded
+        env['wsgi.multiprocess'] = forked
+
+        self.request = req
+
+    def run(self, application):
+        """ Run the application  """
+
+        try:
+            result = application(self.environ, self.start_response)
+
+            for data in result:
+                self.write(data)
+
+            if not self.started:
+                self.request.set_content_length(0)
+
+            if hasattr(result, 'close'):
+                result.close()
+        except:
+            traceback.print_exc(None, self.environ['wsgi.errors'])
+
+            if not self.started:
+                self.request.status = 500
+                self.request.content_type = 'text/plain'
+                data = 'A server error occurred. Please contact the ' + \
+                       'administrator.'
+                self.request.set_content_length(len(data))
+                self.request.write(data)
+
+    def start_response(self, status, headers, exc_info=None):
+        """ Defines the request data  """
+
+        if exc_info:
+            try:
+                if self.started:
+                    raise exc_info[0], exc_info[1], exc_info[2]
+            finally:
+                exc_info = None
+
+        self.request.status = int(status[:3])
+
+        for (key, val) in headers:
+            if key.lower() == 'content-length':
+                self.request.set_content_length(int(val))
+            elif key.lower() == 'content-type':
+                self.request.content_type = val
+            else:
+                self.request.headers_out.add(key, val)
+
+        return self.write
+
+    def write(self, data):
+        """ Write the request data  """
+
+        if not self.started:
+            self.started = True
+
+        self.request.write(data)
+
+
+def handler(req):
+    """ Execute the gluon app  """
+
+    Handler(req).run(gluon.main.wsgibase)
+    return apache.OK
+