Metadata-Version: 1.0
Name: picoweb
Version: 1.8.1
Summary: A very lightweight, memory-efficient async web framework for Pycopy (https://github.com/pfalcon/pycopy) and its uasyncio module.
Home-page: https://github.com/pfalcon/picoweb
Author: Paul Sokolovsky
Author-email: pfalcon@users.sourceforge.net
License: MIT
Description: picoweb
        =======
        
        picoweb is a "micro" web micro-framework (thus, "pico-framework") for
        radically unbloated web applications using radically unbloated Python
        implementation, Pycopy, https://github.com/pfalcon/pycopy .
        
        Features:
        
        * Asynchronous from the start, using unbloated asyncio-like library
          for Pycopy (`uasyncio <https://github.com/pfalcon/pycopy-lib/tree/master/uasyncio>`_).
          This means that ``picoweb`` can process multiple concurrent requests
          at the same time (using I/O and/or CPU multiplexing).
        * Small memory usage. Initial version required about 64K of heap for
          a trivial web app, and since then, it was optimized to allow run
          more or less realistic web app in ~36K of heap. More optimizations
          on all the levels (Pycopy and up) are planned (but may lead to
          API changes).
        * Has API affinity with some well-known Python web micro-framework(s),
          thus it should be an easy start if you have experience with them, and
          existing applications can be potentially ported, instead of requiring
          complete rewrite.
        
        
        Requirements and optional modules
        ---------------------------------
        
        ``picoweb`` depends on ``uasyncio`` for asynchronous networking
        (https://github.com/pfalcon/pycopy-lib/tree/master/uasyncio).
        ``uasyncio`` itself requires `Pycopy <https://github.com/pfalcon/pycopy>`,
        a minimalist, lightweight, and resource-efficient Python language
        implementation.
        
        It is also indended to be used with ``utemplate``
        (https://github.com/pfalcon/utemplate) for templating, but this is
        a "soft" dependency - picoweb offers convenience functions to use
        ``utemplate`` templates, but if you don't use them or will handle
        templating in your app (e.g. with a different library), it won't be
        imported.
        
        For database access, there are following options (``picoweb`` does
        not depend on any of them, up to your application to choose):
        
        * `btree <https://pycopy.readthedocs.io/en/latest/library/btree.html>`_
          builtin Pycopy module. This is a recommended way to do a database
          storage for `picoweb`, as it allows portability across all Pycopy
          targets, starting with very memory- and storage-limited baremetal systems.
        * ``btreedb`` wrapper on top of ``btree`` builtin module. This may add some
          overhead, but may allow to make an application portable between different
          database backends (`filedb` and `uorm` below).
          https://github.com/pfalcon/pycopy-btreedb
        * ``filedb``, for a simple database using files in a filesystem
          https://github.com/pfalcon/filedb
        * ``uorm``, for Sqlite3 database access (works only with Pycopy
          Unix port) https://github.com/pfalcon/uorm
        
        Last but not least, ``picoweb`` uses a standard ``logging``-compatible
        logger for diagnostic output (like a connection opened, errors and debug
        information). However this output is optional, and otherwise you can use
        a custom logging class instead of the standard ``logging``/``ulogging``
        module. Due to this, and to not put additional dependencies burden on
        the small webapps for small systems, ``logging`` module is not included
        in ``picoweb``'s installation dependencies. Instead, a particular app
        using ``picoweb`` should depend on ``pycopy-ulogging`` or
        ``pycopy-logging`` package. Note that to disable use of logging,
        an application should start up using ``WebApp.run(debug=-1)``. The
        default value for ``debug`` parameter is 0 however, in which case
        picoweb will use ``ulogging`` module (on which your application needs
        to depend, again).
        
        
        Details
        -------
        
        picoweb API is roughly based on APIs of other well-known Python web
        frameworks. The strongest affinity is Flask, http://flask.pocoo.org, as
        arguably the most popular micro-framework. Some features are also based on
        Bottle and Django. Note that this does not mean particular "compatibility"
        with Flask, Bottle, or Django: most existing web frameworks are synchronous
        (and threaded), while picoweb is async framework, so its architecture is
        quite different. However, there is an aim to save porting efforts from
        repetitive search & replace trials: for example, when methods do similar
        things, they are likely named the same (but they may take slightly different
        parameters, return different values, and behave slightly differently).
        
        The biggest difference is async, non-threaded nature of picoweb. That means
        that the same code may handle multiple requests at the same time, but unlike
        threaded environment, there's no external context (like thread and thread
        local storage) to associate with each request. Thus, there're no "global"
        (or thread-local "global") request and response objects, like Flask,
        Bottle, Django have. Instead, all picoweb functions explicitly pass the
        current request and response objects around.
        
        Also, picoweb, being unbloated framework, tries to avoid avoidable
        abstractions. For example, HTTP at the lowest level has just read and write
        endpoints of a socket. To dispatch request, picoweb needs to pre-parse
        some request data from input stream, and it saves that partially (sic!)
        parsed data as a "request" object, and that's what passed to application
        handlers. However, there's no unavoidable need to have a "response"
        abstraction - the most efficient/lightweight application may want to
        just write raw HTTP status line, headers, and body to the socket. Thus,
        raw write stream is passed to application handlers as the "response" object.
        (But high-level convenience functions to construct an HTTP response are
        provided).
        
        
        API reference
        -------------
        
        The best API reference currently are examples (see below) and the ``picoweb``
        source code itself. It's under 10K, so enjoy:
        https://github.com/pfalcon/picoweb/blob/master/picoweb/__init__.py
        
        Note that API is experimental and may undergo changes.
        
        
        Examples
        --------
        
        * `example_webapp.py <https://github.com/pfalcon/picoweb/blob/master/example_webapp.py>`_ -
          A simple webapp showing you how to generate a complete HTTP response
          yourself, use ``picoweb`` convenience functions for HTTP headers generation,
          and use of templates. Mapping from URLs to webapp view functions ("web
          routes" or just "routes") is done Django-style, using a centralized route
          list.
        * `example_webapp2.py <https://github.com/pfalcon/picoweb/blob/master/example_webapp2.py>`_ -
          Like above, but uses ``app.route()`` decorator for route specification,
          Flask-style.
        * `examples/ <https://github.com/pfalcon/picoweb/tree/master/examples>`_ -
          Additional examples for various features of picoweb. See comments in each
          file for additional info. To run examples in this directory, you normally
          would need to have picoweb installed (i.e. available in your ``MICROPYPATH``,
          which defaults to ``~/.micropython/lib/``).
        * `notes-pico <https://github.com/pfalcon/notes-pico>`_ - A more realistic
          example webapp, ported from the Flask original.
        
        
        Running under CPython (regressed)
        ---------------------------------
        
        Initial versions of picoweb could run under CPython, but later it was
        further optimized for Pycopy, and ability to run under CPython
        regressed. It's still on TODO to fix it, instructions below tell how
        it used to work.
        
        At least CPython 3.4.2 is required (for asyncio loop.create_task() support).
        To run under CPython, uasyncio compatibility module for CPython is required
        (pycopy-cpython-uasyncio). This and other dependencies can be installed
        using requirements-cpython.txt::
        
            pip install -r requirements-cpython.txt
        
        Reporting Issues
        ----------------
        
        Here are a few guidelines to make feedback more productive:
        
        1. Please be considerate of the overall best practices and common pitfalls in
           reporting issues, this document gives a good overview:
           `How to Report Bugs Effectively <https://www.chiark.greenend.org.uk/~sgtatham/bugs.html>`_.
        2. The reference platform for ``picoweb`` is the Unix port of Pycopy. All issues
           reported must be validated against this version, to differentiate issues of
           ``picoweb``/``uasyncio`` from the issues of your underlying platform.
        3. All reports must include version information of all components involved:
           Pycopy, picoweb, uasyncio, uasyncio.core, any additional modules. Generally,
           only the latest versions of the above are supported (this is what you get when
           you install/reinstall components using the ``upip`` package manager). The
           version information are thus first of all important for yourself, the issue
           reporter, it allows you to double-check if you're using an outdated or
           unsupported component.
        4. Feature requests: ``picoweb`` is by definition a pico-framework, and bound
           to stay so. Feature requests are welcome, but please be considerate that
           they may be outside the scope of core project. There's an easy way out
           though: instead of putting more stuff *into* ``picoweb``, build new things
           *on top* of it: via plugins, subclassing, additional modules etc. That's
           how it was intended to be from the beginning!
        5. We would like to establish a dedicated QA team to support users of this
           project better. If you would like to sponsor this effort, please let us
           know.
        
Platform: UNKNOWN
