This class is instantiated for each request to be handled. The constructor sets the instance variables request, client_address and server, and then calls the handle() method. To implement a specific service, all you need to do is to derive a class which defines a handle() method. The handle() method can find the request as self.request, the client address as self.client_address, and the server (in case it needs access to per-server information) as self.server. Since a separate instance is created for each request, the handle() method can define arbitrary other instance variariables. """ def __init__(self, request, client_address, server): self.request = request self.client_address = client_address self.server = server try: self.setup() self.handle() self.finish() finally: sys.exc_traceback = None # Help garbage collection def setup(self): pass def handle(self): pass def finish(self): pass # The following two classes make it possible to use the same service# class for stream or datagram servers.# Each class sets up these instance variables:# - rfile: a file object from which receives the request is read# - wfile: a file object to which the reply is written# When the handle() method returns, wfile is flushed properly class StreamRequestHandler(BaseRequestHandler): """Define self.rfile and self.wfile for stream sockets.""" # Default buffer sizes for rfile, wfile. # We default rfile to buffered because otherwise it could be # really slow for large data (a getc() call per byte); we make # wfile unbuffered because (a) often after a write() we want to # read and we need to flush the line; (b) big writes to unbuffered # files are typically optimized by stdio even when big reads # aren't. rbufsize = -1 wbufsize = 0 def setup(self): self.connection = self.request self.rfile = self.connection.makefile('rb', self.rbufsize) self.wfile = self.connection.makefile('wb', self.wbufsize) def finish(self): if not self.wfile.closed: self.wfile.flush() self.wfile.close() self.rfile.close() class DatagramRequestHandler(BaseRequestHandler): # XXX Regrettably, I cannot get this working on Linux; # s.recvfrom() doesn't return a meaningful client address. """Define self.rfile and self.wfile for datagram sockets.""" def setup(self): try: from cStringIO import StringIO except ImportError: from StringIO import StringIO self.packet, self.socket = self.request self.rfile = StringIO(self.packet) self.wfile = StringIO() def finish(self): self.socket.sendto(self.wfile.getvalue(), self.client_address)Lines 501–588 of 588. Previous lines
This class is instantiated for each request to be handled. The constructor sets the instance variables request, client_address and server, and then calls the handle() method. To implement a specific service, all you need to do is to derive a class which defines a handle() method. The handle() method can find the request as self.request, the client address as self.client_address, and the server (in case it needs access to per-server information) as self.server. Since a separate instance is created for each request, the handle() method can define arbitrary other instance variariables. """ def __init__(self, request, client_address, server): self.request = request self.client_address = client_address self.server = server try: self.setup() self.handle() self.finish() finally: sys.exc_traceback = None # Help garbage collection def setup(self): pass def handle(self): pass def finish(self): pass # The following two classes make it possible to use the same service # class for stream or datagram servers. # Each class sets up these instance variables: # - rfile: a file object from which receives the request is read # - wfile: a file object to which the reply is written # When the handle() method returns, wfile is flushed properly class StreamRequestHandler(BaseRequestHandler): """Define self.rfile and self.wfile for stream sockets.""" # Default buffer sizes for rfile, wfile. # We default rfile to buffered because otherwise it could be # really slow for large data (a getc() call per byte); we make # wfile unbuffered because (a) often after a write() we want to # read and we need to flush the line; (b) big writes to unbuffered # files are typically optimized by stdio even when big reads # aren't. rbufsize = -1 wbufsize = 0 def setup(self): self.connection = self.request self.rfile = self.connection.makefile('rb', self.rbufsize) self.wfile = self.connection.makefile('wb', self.wbufsize) def finish(self): if not self.wfile.closed: self.wfile.flush() self.wfile.close() self.rfile.close() class DatagramRequestHandler(BaseRequestHandler): # XXX Regrettably, I cannot get this working on Linux; # s.recvfrom() doesn't return a meaningful client address. """Define self.rfile and self.wfile for datagram sockets.""" def setup(self): try: from cStringIO import StringIO except ImportError: from StringIO import StringIO self.packet, self.socket = self.request self.rfile = StringIO(self.packet) self.wfile = StringIO() def finish(self): self.socket.sendto(self.wfile.getvalue(), self.client_address)