Refactor WSGI handlers and add new functionalities

Author: grongierisc

src/grongier/pex/wsgi/handlers.py

@@ -1,51 +1,104 @@
-from wsgiref.handlers import BaseHandler
-import io
+import os, sys, importlib, urllib.parse
+from io import BytesIO
+
+__ospath = os.getcwd()
+
 import iris
 
-class IrisHandler(BaseHandler):
-    """Handler that's just initialized with streams, environment, etc.
+os.chdir(__ospath)
+
+enc, esc = sys.getfilesystemencoding(), 'surrogateescape'
+
+rest_service = iris.cls('%REST.Impl')
+
+def get_from_module(app_path, app_module, app_name):
+
+    # Add the path to the application
+    if (app_path not in sys.path) :
+        sys.path.append(app_path)
+
+    # retrieve the application
+    return getattr(importlib.import_module(app_module), app_name)
+
+# Changes the current working directory to the manager directory of the instance.
+def goto_manager_dir():
+    iris.system.Process.CurrentDirectory(iris.system.Util.ManagerDirectory())
+
+def unicode_to_wsgi(u):
+    # Convert an environment variable to a WSGI "bytes-as-unicode" string
+    return u.encode(enc, esc).decode('iso-8859-1')
+
+def wsgi_to_bytes(s):
+    return s.encode('iso-8859-1')
+
+def write(chunk):
+    rest_service._WriteResponse(chunk)
+
+def start_response(status, response_headers, exc_info=None):
+    '''WSGI start_response callable'''
+    if exc_info:
+        try:
+            raise exc_info[1].with_traceback(exc_info[2])
+        finally:
+            exc_info = None
 
-    This handler subclass is intended for synchronous HTTP/1.0 origin servers,
-    and handles sending the entire response output, given the correct inputs.
+    rest_service._SetStatusCode(status)
+    for tuple in response_headers:
+        rest_service._SetHeader(tuple[0], tuple[1])
+    return write
 
-    Usage::
 
-        handler = SimpleHandler(
-            inp,out,err,env, multithread=False, multiprocess=True
-        )
-        handler.run(app)"""
+# Make request to application
+def make_request(environ, stream, application, path):
 
-    server_software = "IrisWSGI/0.1"
-    wsgi_file_wrapper = None
+    # Change the working directory for logging purposes
+    goto_manager_dir()
 
-    def __init__(self,stdin,stdout,stderr,environ,
-        multithread=True, multiprocess=False
-    ):
-        self.stdin = stdin
-        self.stdout = stdout
-        self.stderr = stderr
-        self.base_env = environ
-        self.wsgi_multithread = multithread
-        self.wsgi_multiprocess = multiprocess
+    error_log_file = open('WSGI.log', 'a+')
+    
+    # We want the working directory to be the app's directory
+    if (not path.endswith(os.path.sep)):
+        path = path + os.path.sep
 
-    def get_stdin(self):
-        if not self.stdin:
-            return None
-        else:
-            self.environ["wsgi.input"] = io.BytesIO(self.stdin)
-            self.environ["CONTENT_LENGTH"] = str(len(self.stdin))
-            return io.BytesIO(self.stdin)
+    #iris.system.Process.CurrentDirectory(path)
+    
+    # Set up the body of the request
+    if stream != '':
+        bytestream = stream
+    elif (environ['CONTENT_TYPE'] == 'application/x-www-form-urlencoded'):
+        bytestream = BytesIO()
+        part = urllib.parse.urlencode(environ['formdata'])
+        bytestream.write(part.encode('utf-8'))
+        bytestream.seek(0)
+    else:
+        bytestream = BytesIO(b'')
 
+    #for k,v in os.environ.items():
+        #environ[k] = unicode_to_wsgi(v)
+    environ['wsgi.input'] = bytestream   
+    environ['wsgi.errors'] = error_log_file
+    environ['wsgi.version']      = (1, 0)
+    environ['wsgi.multithread']  = False
+    environ['wsgi.multiprocess'] = True
+    environ['wsgi.run_once']     = True
 
-    def get_stderr(self):
-        return self.stderr
 
-    def add_cgi_vars(self):
-        self.environ.update(self.base_env)
+    if environ.get('HTTPS', 'off') in ('on', '1'):
+        environ['wsgi.url_scheme'] = 'https'
+    else:
+        environ['wsgi.url_scheme'] = 'http'
+    
+    # Calling WSGI application
+    response = application(environ, start_response)
 
-    def _write(self,data):
-        iris.cls('Grongier.Service.WSGI').write(data)
+    error_log_file.close()
 
-    def _flush(self):
-        self.stdout.flush()
-        self._flush = self.stdout.flush
+    try:
+        for data in response:
+            if data:
+                # (REST.Impl).Write() needs a utf-8 string
+                write(data.decode('utf-8'))
+            write(b'')
+    finally:
+        if hasattr(response, 'close'):
+            response.close()