Deploying Patchwork

Patchwork uses the django framework - there is some background on deploying
django applications here:

 http://www.djangobook.com/en/2.0/chapter12/

You'll need the following (applications used for patchwork development are
in brackets):

  * A python interpreter
  * django >= 1.5
  * A webserver (apache)
  * mod_python or flup
  * A database server (postgresql, mysql)
  * relevant python modules for the database server (e.g: python-mysqldb)

1. Database setup

    At present, I've tested with PostgreSQL and (to a lesser extent) MySQL
    database servers. If you have any (positive or negative) experiences with
    either, email me.

    For the following commands, a $ prefix signifies that the command should be
    entered at your shell prompt, and a > prefix signifies the command-line
    client for your sql server (psql or mysql)

    Create a database for the system, add accounts for two system users: the
    web user (the user that your web server runs as) and the mail user (the
    user that your mail server runs as). On Ubuntu these are
    www-data and nobody, respectively.

    As an alternative, you can use password-based login and a single database
    account. This is described further down.

    For PostgreSQL (ident-based)

        $ createdb patchwork
        $ createuser www-data
        $ createuser nobody

        - postgres uses the standard UNIX authentication, so these users
          will only be accessible for processes running as the same username.
          This means that no passwords need to be set.

    For PostgreSQL (password-based)

        $ createuser -PE patchwork
        $ createdb -O patchwork patchwork

        Once that is done, you need to tell Django about the new Database
        settings, using local_settings.py (see below) to override the defaults
        in settings.py:

        DATABASES = {
            'default': {
                'ENGINE': 'django.db.backends.postgresql_psycopg2',
                'HOST': 'localhost',
                'PORT': '',
                'USER': 'patchwork',
                'PASSWORD': 'my_secret_password',
                'NAME': 'patchwork',
            },
        }

    For MySQL:
        $ mysql
        > CREATE DATABASE patchwork CHARACTER SET utf8;
        > CREATE USER 'www-data'@'localhost' IDENTIFIED BY '<password>';
        > CREATE USER 'nobody'@'localhost' IDENTIFIED BY '<password>';

	Once that is done, you need to tell Django about the new Database
	settings, using local_settings.py (see below) to override the defaults
	in settings.py:

        DATABASES = {
            'default': {
                'ENGINE': 'django.db.backends.mysql',
                'HOST': 'localhost',
                'PORT': '',
                'USER': 'patchwork',
                'PASSWORD': 'my_secret_password',
                'NAME': 'patchwork',
                'TEST_CHARSET': 'utf8',
            },
        }

        TEST_CHARSET is used when creating tables for the test suite. Without
        it, tests checking for the correct handling of non-ASCII characters
        fail.

2. Django setup

        Set up some initial directories in the patchwork base directory:

         mkdir -p lib/packages lib/python

        lib/packages is for stuff we'll download; lib/python is to add
        to our python path. We'll symlink python modules into lib/python.

        At the time of release, patchwork depends on django version 1.5 or
        later. Your distro probably provides this. If not, do a:

         cd lib/packages
	  git clone https://github.com/django/django.git -b stable/1.5.x
         cd ../python
         ln -s ../packages/django/django ./django

        The settings.py file contains default settings for patchwork, you'll
        need to configure settings for your own setup.

        Rather than edit settings.py, create a file 'local_settings.py', and
        override or add settings as necessary. You'll need to define the
        following:

          SECRET_KEY
          ADMINS
          TIME_ZONE
          LANGUAGE_CODE
          DEFAULT_FROM_EMAIL
          NOTIFICATION_FROM_EMAIL

        You can generate the SECRET_KEY with the following python code:

          import string, random
          chars = string.letters + string.digits + string.punctuation
          print repr("".join([random.choice(chars) for i in range(0,50)]))

        If you wish to enable the XML-RPC interface, add the following to
        your local_settings.py file:

          ENABLE_XMLRPC = True

        Then, get patchwork to create its tables in your configured database:

         cd apps/
         PYTHONPATH=../lib/python ./manage.py syncdb

        And add privileges for your mail and web users. This is only needed if
        you use the ident-based approach. If you use password-based database
        authentication, you can skip this step.

        Postgresql:
          psql -f lib/sql/grant-all.postgres.sql patchwork

        MySQL:
          mysql patchwork < lib/sql/grant-all.mysql.sql


3. Apache setup

Example apache configuration files are in lib/apache2/.

wsgi:
        django has built-in support for WSGI, which supersedes the fastcgi
        handler. It is thus the preferred method to run patchwork.

        The necessary configuration for Apache2 may be found in

         lib/apache2/patchwork.wsgi.conf.

        You will need to install/enable mod_wsgi for this to work:

         a2enmod wsgi
         apache2ctl restart

mod_python:

        An example apache configuration file for mod_python is in:

          lib/apache2/patchwork.mod_python.conf

        However, mod_python and mod_php may not work well together. So, if your
        web server is used for serving php files, the fastcgi method may suit
        instead.

fastcgi:

        django has built-in support for fastcgi, which requires the
        'flup' python module. An example configuration is in:

          lib/apache2/patchwork.fastcgi.conf

        - this also requires the mod_rewrite apache module to be loaded.

        Once you have apache set up, you can start the fastcgi server with:

          cd /srv/patchwork/apps
          ./manage.py runfcgi method=prefork \
                              socket=/srv/patchwork/var/fcgi.sock \
                              pidfile=/srv/patchwork/var/fcgi.pid

4. Configure patchwork
    Now, you should be able to administer patchwork, by visiting the
    URL:

      http://your-host/admin/

    You'll probably want to do the following:

      * Set up your projects
      * Configure your website address (in the Sites) section

5. Subscribe a local address to the mailing list

     You will need an email address for patchwork to receive email on - for
     example - patchwork@, and this address will need to be subscribed to the
     list. Depending on the mailing list, you will probably need to confirm the
     subscription - temporarily direct the alias to yourself to do this.

6. Setup your MTA to deliver mail to the parsemail script

    Your MTA will need to deliver mail to the parsemail script in the email/
    directory. (Note, do not use the parsemail.py script directly). Something
    like this in /etc/aliases is suitable for postfix:

      patchwork: "|/srv/patchwork/apps/patchwork/bin/parsemail.sh"

    You may need to customise the parsemail.sh script if you haven't installed
    patchwork in /srv/patchwork.

    Test that you can deliver a patch to this script:

     sudo -u nobody /srv/patchwork/apps/patchwork/bin/parsemail.sh < mail

7. Set up the patchwork cron script

    Patchwork uses a cron script to clean up expired registrations, and
    send notifications of patch changes (for projects with this enabled).

    Something like this in your crontab should work:

      # m h  dom mon dow   command
      PYTHONPATH=apps:.
      DJANGO_SETTINGS_MODULE=settings
      */10 * * * * cd patchwork; python apps/patchwork/bin/patchwork-cron.py


    - the frequency should be the same as the NOTIFICATION_DELAY_MINUTES
    setting, which defaults to 10 minutes.

8. Optional: Configure your VCS to automatically update patches

    The tools directory of the patchwork distribution contains a file
    named post-receive.hook which is an example git hook that can be
    used to automatically update patches to the Accepted state when
    corresponding comits are pushed via git.

    To install this hook, simply copy it to the .git/hooks directory on
    your server, name it post-receive, and make it executable.

    This sample hook has support to update patches to different states
    depending on which branch is being pushed to. See the STATE_MAP
    setting in that file.

    If you are using a system other than git, you can likely write a
    similar hook using pwclient to update patch state. If you do write
    one, please contribute it.

Some errors:

* __init__() got an unexpected keyword argument 'max_length'

 - you're running an old version of django. If your distribution doesn't
   provide a newer version, just download and extract django into
   lib/python/django

* ERROR: permission denied for relation patchwork_...

 - the user that patchwork is running as (ie, the user of the web-server)
   doesn't have access to the patchwork tables in the database. Check that
   your web-server user exists in the database, and that it has permissions
   to the tables.

* pwclient fails for actions that require authentication, but a username
  and password is given in ~/.pwclientrc. Server reports "No authentication
  credentials given".

 - if you're using the FastCGI interface to apache, you'll need the
   '-pass-header Authorization' option to the FastCGIExternalServer
   configuration directive.