Metadata-Version: 1.0
Name: sauna.reload
Version: 0.3.2
Summary: Instant code reloading for Plone using a fork loop.
Home-page: http://github.com/epeli/sauna.reload
Author: Esa-Matti Suuronen
Author-email: esa-matti@suuronen.org
License: ZPL
Description: .. figure:: https://github.com/epeli/sauna.reload/raw/gh-pages/saunasprint_logo.jpg
        
        *sauna.reload: so that you can finish your Plone development today and relax in
        sauna after calling it a day*
        
        .. contents:: :local:
        
        
        Introduction
        =============
        
        ``sauna.reload`` partially restarts Plone and reloads your changed source
        code every time you save a file.
        
        * Edit your code
        * Save
        * Go to a browser and hit *Refresh* |->| your latest changes are active
        
        It greatly simplifies your Plone development workflow and gives back the
        agility of Python.
        
        It works with any code.
        
        ``sauna.reload`` works on OSX and Linux with Plone 4.0 and 4.1. In theory
        works on Windows, but no one has looked into that yet.
        
        .. |->| unicode:: U+02794 .. thick rightwards arrow
        
        
        Installation
        ==============
        
        Here are brief installation instructions.
        
        
        Prerequisitements
        -----------------
        
        In order to take the advantage of ``sauna.reload``
        
        * You know how to develop your own Plone add-ons and basics of buildout folder
          structure
        
        * You know UNIX command line basics
        
        * You know how to run buildout
        
        No knowledge for warming up sauna is needed in order to use this product.
        
        .. note:: Currently it is recommended to install sauna.reload directly from
           GitHub as it is under heavy development.
        
        
        Using new buildout file for the development
        -------------------------------------------
        
        This is the recommended approach how to enable ``sauna.reload`` for your
        development environment.
        
        Use git to fetch  ``sauna.reload`` source code to your buildout environment::
        
          cd src
          git clone git://github.com/epeli/sauna.reload.git
        
        Create a new buildout file ``development.cfg`` which extends your existing
        ``buildout.cfg`` – this way you can easily keep development stuff separate
        from your main buildout.cfg which you can also use on the production server.
        
        ``development.cfg``::
        
          [buildout]
        
          extends = buildout.cfg
        
          develop +=
              src/sauna.reload
        
          [instance]
        
          # XXX: May conflict with existing zope-conf-additional directives
          zope-conf-additional = %import sauna.reload
        
          eggs +=
              sauna.reload
        
        .. note:: With this approach you do not need to modify the existing
           buildout.cfg.
        
        Then build it out with this special config file::
        
          bin/buildout -c development.cfg
        
        *I like to buildout buildout. I like to buildout buildout...*
        
        
        OSX special notes
        +++++++++++++++++
        
        .. note:: The following applies to OSX only until Watchog 0.5.4+ is released.
        
        For OSX you need to install trunk version of WatchDog providing `FSEvents
        <http://en.wikipedia.org/wiki/FSEvents>`_ based file-system monitoring support.
        
        Use git to fetch  ``watchdog`` source code to your buildout environment::
        
          cd src
          git clone git://github.com/gorakhargosh/watchdog.git
         
        Add ``watchdog`` as a developed egg into your buildout configuration just next
        to ``sauna.reload``.
        
        ``development.cfg``::
        
          [buildout]
        
          develop +=
              src/watchdog
              src/sauna.reload
        
        If you are using vim (or macvim) on OSX, you must disable vim's writebackups to
        allow WatchDog to see your modifications (otherwise vim will technically create
        a new file on each save and WatchDog doesn't really understand what happened).
        
        So, Add the following to the end of your ``.vimrc``::
        
          set noswapfile
          set nobackup
          set nowritebackup
        
        
        Updating the existing buildout.cfg
        ----------------------------------
        
        Alternatively you can just hack your existing buildout.cfg to have
        ``sauna.reload``.
        
        Add this package to your buildout eggs and add following
        ``zope-conf-additional`` line  to you instance part of buildout.cfg::
        
          [instance]
          recipe = plone.recipe.zope2instance
          ...
          zope-conf-additional = %import sauna.reload
        
        
        Usage: start Plone in reload enabled manner
        ===========================================
        
        To start Plone with reload functionality you need
        to give special environment variable ``RELOAD_PATH``
        for your instance command::
        
          RELOAD_PATH=src bin/instance fg
        
        Or if you want to optimize load speed you can directly specify only some of
        your development products::
        
          RELOAD_PATH=src/my.product:src/my.another.product bin/instance fg
        
        .. warning:: If other products depend on your product, e.g CMFPlone
           dependencies, sauna.reload does not kick in early enough and the reload does
           not work.
        
        When reload is active you should see something like this in your console
        when Zope starts up::
        
          2011-08-10 13:28:59 INFO sauna.reload Starting file monitor on /Users/moo/code/x/plone4/src
          2011-08-10 13:29:02 INFO sauna.reload We saved at least 29.8229699135 seconds from boot up time
          2011-08-10 13:29:02 INFO sauna.reload Packages marked for reload are listed in here: http://127.0.0.1:8080/@@saunareload
          2011-08-10 13:29:02 INFO sauna.reload Fork loop starting on process 14607
          2011-08-10 13:29:02 INFO sauna.reload Booted up new new child in 0.104816913605 seconds. Pid 14608
        
        ... and when you save some file in ``src`` folder::
        
          2011-08-10 13:29:41 INFO SignalHandler Caught signal SIGINT
          2011-08-10 13:29:41 INFO Z2 Shutting down
          2011-08-10 13:29:42 INFO SignalHandler Caught signal SIGCHLD
          2011-08-10 13:29:42 INFO sauna.reload Booted up new new child in 0.123936891556 seconds. Pid 14609
        
        CTRL+C should terminate Zope normally. There might be stil some kinks and error
        messages with shutdown.
        
        .. note:: Your reloadable eggs must be included using z3c.autoinclude
           mechanism.
        
        Only eggs loaded through `z3c.autoinclude
        <http://plone.org/products/plone/roadmap/247>`_.  can be reloaded. Make sure
        you don't use buildout.cfg ``zcml =`` directive for your eggs or
        ``sauna.reload`` silently ignores changes.
        
        
        Manual reload
        -------------
        
        There is also a view on Zope2 root from which it is possible to manually reload
        code::
        
          http://127.0.0.1:8080/@@saunareload
        
        
        Debugging with ``sauna.reload``
        ===============================
        
        Regular ``import pdb; pdb.set_trace()`` will work just fine with
        ``sauna.reload``. When reload happens while in pdb, though, pdb will get
        killed. To avoid losing your terminal echo, because of reload unexpectedly
        killing your pdb, you may add the following to your ``~/.pdbrc``::
        
          import termios, sys
          term_fd = sys.stdin.fileno()
          term_echo = termios.tcgetattr(term_fd)
          term_echo[3] = term_echo[3] | termios.ECHO
          term_result = termios.tcsetattr(term_fd, termios.TCSADRAIN, term_echo)
        
        ``sauna.reload`` also should work nicely with `PdbTextMateSupport
        <http://pypi.python.org/pypi/PdbTextMateSupport>`_ and `PdbSublimeTextSupport
        <http://pypi.python.org/pypi/PdbSublimeTextSupport>`_. Unfortunately, we
        haven't seen it working with ``vimpdb`` yet.
        
        
        Background
        ==========
        
        ``sauna.reload`` is an attempt to recreate ``plone.reload`` without the issues
        it has. Like being unable to reload new grokked views or portlet code. This
        project was started on Plone Sauna Sprint 2011. There for the name,
        ``sauna.reload``.
        
        ``sauna.reload`` does reloading by using a fork loop. So actually it does not
        reload the code, but restarts small part of Zope2. That's why it can it reload
        stuff ``plone.reload`` cannot.
        
        It does following on Zope2 startup:
        
        1. Defers loading of your development packages by hooking into PEP 302 loader
           and changing their ``z3c.autoinclude`` target module (and monkeypatching
           fiveconfigure/metaconfigure for legacy packages).
        
        2. Starts a watcher thread which monitors changes in your development py-files
        
        3. Stops loading of Zope2 in ``zope.processlifetime.IProcessStarting`` event by
           stepping into a infinite loop; Just before this, tries to load all
           non-developed dependencies of your development packages (resolved by
           ``z3c.autoinclude``)
        
        4. It forks a new child and lets it pass the loop
        
        5. Loads all your development packages invoking ``z3c.autoinclude`` (and
           fiveconfigure/metaconfigure for legacy packages). This is fast!
        
        6. And now every time when the watcher thread detects a change in development
           files it will signal the child to shutdown and the child will signal
           the parent to fork a new child when it is just about to close itself
        
        7. Just before dying, the child saves ``Data.fs.index`` to help the new child
           to see the changes in ZODB (by loading the saved index)
        
        8. GOTO 4
        
        Internally ``sauna.reload`` uses
        `WatchDog <http://pypi.python.org/pypi/watchdog>`_
        Python component for monitoring file-system change events.
        
        See also `Ruby guys on fork trick <http://www.youtube.com/watch?feature=player_detailpage&v=ghLCtCwAKqQ#t=286s>`_.
        
        
        Events
        ======
        
        .. note:: The following concerns you only if your code needs to react specially
           to reloads (clear caches, etc.)
        
        ``sauna.reload`` emits couple of events during reloading.
        
        **sauna.reload.events.INewChildForked**
          Emited immediately after new process is forked. No development packages have
          been yet installed.  Useful if you want to do something before your code gets
          loaded.  Note that you cannot listen this event on a package that is marked
          for reloading as it is not yet installed when this is fired.
        
        **sauna.reload.events.INewChildIsReady**
          Emitted when all the development packages has been installed to the new
          forked child.  Useful for notifications etc.
        
        
        Limitations
        ===========
        
        ``sauna.reload`` has a major pitfall. Because it depends on deferring loading
        of packages to be watched and reloaded, also every package depending on those
        packages should be defined to be reloaded (in ``RELOAD_PATH``). And
        ``sauna.reload`` doesn't resolve those dependencies automatically!
        
        An another potential troublemaker is that ``sauna.reload`` performs implicit
        ``<includeDependencies package="." />`` for every package in ``RELOAD_PATH``
        (to preload dependencies for those packages to speed up the reload).
        
        We are sorry that ``sauna.reload`` may not work for everyone. For example,
        reloading of core Plone packages could be tricky, if not impossible, because
        many of them are explicitly included by ``configure.zcml`` of CMFPlone and are
        not using ``z3c.autoincude`` at all. You would have to remove the dependency
        from CMFPlone for development to make it work...
        
        Also because the product installation order is altered (by all the above) you
        may find some issue if your product does something funky on installation or at
        import time.
        
        Currently only FileStorage (ZODB) is supported.
        
        Please report any other issues at:
        https://github.com/epeli/sauna.reload/issues.
        
        
        Troubleshooting
        ===============
        
        Report all issues on `GitHub <https://github.com/epeli/sauna.reload>`_.
        
        
        My code does not reload properly
        --------------------------------
        
        You'll see reload process going on in the terminal, but your code is still not
        loaded.
        
        You should see following warnings with zcml-paths from your products::
        
          2011-08-13 09:38:12 ERROR sauna.reload.child Failed to defer
          src/sauna.reload/sauna/reload/configure.zcml. IT WILL NOT BE RELOADABLE.
        
        Make sure your code is hooked into Plone through
        `z3c.autoinclude <http://plone.org/products/plone/roadmap/247>`_ and NOT
        using explicit ``zcml = directive`` in buildout.cfg.
        
        * Retrofit your eggs with autoinclude support if needed
        * Remove zcml = lines for your eggs in buildout.cfg
        * Rerun buildout (remember bin/buildout -c development.cfg)
        * Restart Plone with sauna.reload enabled
        
        
        I want to exclude my ``meta.zcml`` from reload
        ----------------------------------------------
        
        It's possible to manually exclude configuration files from reloading by
        forcing them to be loaded by a custom ``site.zcml``. Be aware, that
        when ``site-zcml`` option is used, ``zope2instance`` ignores ``zcml`` and
        ``zcml-additional`` options.
        
        Define a custom ``site.zcml`` in your ``buildout.cfg`` with::
        
         [instance]
         recipe = plone.recipe.zope2instance
         ...
         site-zcml =
           <configure xmlns="http://namespaces.zope.org/zope"
                      xmlns:meta="http://namespaces.zope.org/meta"
                      xmlns:five="http://namespaces.zope.org/five">
             <include package="Products.Five" />
             <meta:redefinePermission from="zope2.Public" to="zope.Public" />
             <five:loadProducts file="meta.zcml"/>
             <!-- Add include for your package's meta.zcml here: -->
             <include package="my.product" file="meta.zcml" />
             <five:loadProducts />
             <five:loadProductsOverrides />
             <securityPolicy component="Products.Five.security.FiveSecurityPolicy" />
           </configure>
        
        
        I want to exclude ALL ``meta.zcml`` from reload
        -----------------------------------------------
        
        Sure. See the tip above and use the snippet below instead::
        
         [instance]
         recipe = plone.recipe.zope2instance
         ...
         site-zcml =
           <configure xmlns="http://namespaces.zope.org/zope"
                      xmlns:meta="http://namespaces.zope.org/meta"
                      xmlns:five="http://namespaces.zope.org/five">
             <include package="Products.Five" />
             <meta:redefinePermission from="zope2.Public" to="zope.Public" />
             <five:loadProducts file="meta.zcml"/>
             <!-- Add autoinclude-directive for deferred meta.zcml here: -->
             <includePlugins package="sauna.reload" file="meta.zcml" />
             <five:loadProducts />
             <five:loadProductsOverrides />
             <securityPolicy component="Products.Five.security.FiveSecurityPolicy" />
           </configure>
        
        
        sauna.reload is not active - nothing printed on console
        -------------------------------------------------------
        
        Check that your buildout.cfg includes
        ``zope-conf-additionalzope-conf-additional`` line.
        
        If using separate ``development.cfg`` make sure you run your buildout using
        it::
        
          bin/buildout -c development.cfg
        
        
        Source
        ======
        
        On `GitHub <https://github.com/epeli/sauna.reload>`_.
        
        
        Credits
        =======
        
        * Esa-Matti Suuronen [esa-matti aet suuronen.org]
        * Asko Soukka [asko.soukka aet iki.fi]
        * Mikko Ohtamaa (idea, doccing)
        * Vilmos Somogyi (logo). The logo was originally the logo of Sauna Sprint 2011
          and it was created by Vilmos Somogyi.
        * `Yesudeep Mangalapilly <https://github.com/gorakhargosh>`_ for creating
          ``WatchDog`` component and providing support for Sauna Sprint team using it
        
        Thanks to all happy hackers on Sauna Sprint 2011!
        
        300 kg of beer was consumed to create this package (at least). Also several
        kilos of firewood, one axe, one chainsaw and one boat.
        
        We still need testers and contributors. You are very welcome!
        
        Changelog
        =========
        
        
        0.3.2 – 2011-08-21
        ------------------
        
        - Fix to work better with PdbSublimeText/TextMateSupport.
        - README-updates (mainly for exluding zcmls from reload).
        
        
        0.3.1 – 2011-08-19
        ------------------
        
        - Support for Five-initialized products (e.g. Archetypes) on Plone 4.1.
        - Licensed under ZPL.
        
        0.3.0 – 2011-08-12
        ------------------
        
        - Support Plone 4.1
        - Heavily edited readme [miohtama]
        - Show nice error log message if product installation failed to defer ie. is
          not reloadable.
        
        0.2.1 – 2011-08-03
        ------------------
        
        - Add INewChildIsReady event and move INewChildForked event
        - Remove overly used prints and use logging
        - Can now reload __init__.py from package root
        
        
        0.2.0 – 2011-08-04
        ------------------
        
        - Support for Five-initialized products (e.g. Archetypes).
        - Browser View for manual reloading
        - Emit INewChildForked events
        - Many bug fixes
        
        0.1.1 – 2011-08-03
        ------------------
        
        - Added missing egg description.
        - Added forgotten reload for localizations.
        - Prefixed commands in README with $.
        
        0.1.0 – 2011-08-03
        ------------------
        
        - First experimental release.
        
Keywords: plone reload zope2 restart developer
Platform: UNKNOWN
Classifier: Framework :: Plone
Classifier: Programming Language :: Python
