Metadata-Version: 1.0
Name: m2wsgi
Version: 0.3.0
Summary: a mongrel2 => wsgi gateway
Home-page: http://github.com/rfk/m2wsgi/
Author: Ryan Kelly
Author-email: ryan@rfk.id.au
License: MIT
Description: 
        
        m2wsgi:  a mongrel2 => wsgi gateway
        ===================================
        
        
        This module provides a WSGI gateway handler for the Mongrel2 webserver,
        allowing easy deployment of python apps on Mongrel2.  It provides full support
        for chunked response encoding, streaming reads of large file uploads, and
        pluggable backends for evented I/O a la eventlet.
        
        You might also find its supporting classes useful for developing non-WSGI
        handlers in python.
        
        
        
        Command-line usage
        ------------------
        
        The simplest way to use this package is as a command-line launcher::
        
            m2wsgi dotted.app.name tcp://127.0.0.1:9999
        
        This will connect to Mongrel2 on the specified request port and start handling
        requests by passing them through the specified WSGI app.  By default you will
        get a single worker thread handling all requests, which is probably not what
        you want; increase the number of threads like so::
        
            m2wsgi --num-threads=5 dotted.app.name tcp://127.0.0.1:9999
        
        If threads aren't your thing, you can just start several instances of the
        handler pointing at the same zmq socket and get the same effect.  Better yet,
        you can use eventlet to shuffle the bits around like so::
        
            m2wsgi --io=eventlet dotted.app.name tcp://127.0.0.1:9999
        
        You can also use --io=gevent if that's how you roll.  Contributions for
        other async backends are most welcome.
        
        
        Programmatic Usage
        ------------------
        
        If you have more complicated needs, you can use m2wsgi from within your
        application.  The main class is 'WSGIHandler' which provides a simple
        server interface.  The equivalent of the above command-line usage is::
        
            from m2wsgi.base import WSGIHandler
            handler = WSGIHandler(my_wsgi_app,"tcp://127.0.0.1:9999")
            handler.serve()
        
        There are a lot of "sensible defaults" being filled in here.  It assumes
        that the Mongrel2 recv socket is on the next port down from the send socket,
        and that it's OK to connect the socket without a persistent identity.
        
        For finer control over the connection between your handler and Mongrel2,
        create your own Connection object::
        
            from m2wsgi.base import WSGIHandler, Connection
            conn = Connection(send_spec="tcp://127.0.0.1:9999",
                              recv_spec="tcp://127.0.0.1:9992",
                              send_ident="9a5eee79-dbd5-4f33-8fd0-69b304c6035a")
            handler = WSGIHandler(my_wsgi_app,conn)
            handler.serve()
        
        If you're creating non-WSGI handlers for Mongrel2 you might find the following
        classes useful:
        
            :Connection:  represents the connection from your handler to Mongrel2,
                          through which you can read requests and rend responses.
        
            :Request:     represents a client request to which you can asynchronously
                          send response data at any time.
        
        
        Don't we already have one of these?
        -----------------------------------
        
        Yes, there are several existing WSGI gateways for Mongrel2:
        
            * https://github.com/berry/Mongrel2-WSGI-Handler
            * https://bitbucket.org/dholth/mongrel2_wsgi
        
        None of them fully met my needs.  In particular, this package has transparent
        support for:
        
            * chunked response encoding
            * streaming reads of large "async upload" requests
            * pluggable IO backends (e.g. eventlet, gevent)
        
        It's also designed from the ground up specifically for Mongrel2.  This means
        it gets a lot of functionality for free, and the code is simpler and lighter
        as a result.
        
        For example, there is no explicit management of a threadpool and request queue
        as you might find in e.g. the CherryPy server.  Instead, you just start up
        as many threads as you need, have them all connect to the same handler socket,
        and mongrel2 (via zmq) will automatically load-balance the requests to them.
        
        Similarly, there's no explicit support for reloading when the code changes.
        Just kill the old handler and start up a new one.  If you're using fixed
        handler UUIDs then zmq will ensure that the handover happens gracefully.
        
        
        Current bugs, limitations and things to do
        ------------------------------------------
        
        It's not all perfect just yet, although it does seem to mostly work:
        
            * Needs tests something fierce!  I just have to find the patience to
              write the necessary setup and teardown cruft.
        
            * When running multiple threads, ctrl-C doesn't cleanly exit the process.
              Seems like the background threads get stuck in a blocking recv().
              I *really* don't want to emulate interrupts using zmq_poll...
        
            * The zmq load-balancing algorithm is greedy round-robin, which isn't
              ideal.  For example, it can schedule several fast requests to the same
              thread as a slow one, making them wait even if other threads become
              available.  I'm working on a zmq adapter that can do something better
              (see the pull2xreq device in this distribution).
        
            * It would be great to grab connection details straight from the
              mongrel2 config database.  Perhaps a Connection.from_config method
              with keywords to select the connection by handler id, host, route etc.
        
        
        
Keywords: wsgi mongrel2
Platform: UNKNOWN
Classifier: Programming Language :: Python
Classifier: Programming Language :: Python :: 2
Classifier: Programming Language :: Python :: 3
Classifier: Development Status :: 4 - Beta
Classifier: License :: OSI Approved :: MIT License
