Updated prerequisite list for PHP5.4

[quix0rs-gnu-social.git] / INSTALL

Prerequisites
=============

The following software packages are *required* for this software to
run correctly.

- PHP 5.4+      For newer versions, some functions that are used may be
                disabled by default, such as the pcntl_* family. See the
                section on 'Queues and daemons' for more information.
- MariaDB 5+    GNU Social uses, by default, a MariaDB server for data
                storage. Versions 5.x and 10.x have both reportedly
                worked well. It is also possible to run MySQL 5.x.
- Web server    Apache, lighttpd and nginx will all work. CGI mode is
                recommended and also some variant of 'suexec' (or a
                proper setup php-fpm pool)
                NOTE: mod_rewrite or its equivalent is extremely useful.

Your PHP installation must include the following PHP extensions for a
functional setup of GNU Social:

- php5-curl     Fetching files by HTTP.
- php5-gd       Image manipulation (scaling).
- php5-gmp      For Salmon signatures (part of OStatus).
- php5-json     For WebFinger lookups and more.
- php5-mysqlnd  The native driver for PHP5 MariaDB connections. If you
                  use MySQL, 'mysql' or 'mysqli' may work.

The above package names are for Debian based systems. In the case of
Arch Linux, PHP is compiled with support for most extensions but they
require manual enabling in the relevant php.ini file (mostly php5-gmp).

Better performance
------------------

For some functionality, you will also need the following extensions:

- memcache      A client for the memcached server, which caches database
                information in volatile memory. This is important for
                adequate performance on high-traffic sites. You will
                also need a memcached server to store the data in.
- mailparse     Efficient parsing of email requires this extension.
                Submission by email or SMS-over-email uses this.
- sphinx        A client for the sphinx server, an alternative to MySQL
                or Postgresql fulltext search. You will also need a
                Sphinx server to serve the search queries.
- gettext       For multiple languages. Default on many PHP installs;
                will be emulated if not present.
- exif          For thumbnails to be properly oriented.

You may also experience better performance from your site if you install
a PHP bytecode cache/accelerator. Currently the recommended cache module
is 'xcache', which after installation (php5-xcache) can be enabled in
your site's config.php with:

    addPlugin('XCache');

External libraries
------------------

A number of external PHP libraries are used to provide basic
functionality and optional functionality for your system. For your
convenience, they are available in the "extlib" directory of this
package, and you do not have to download and install them. However,
you may want to keep them up-to-date with the latest upstream version,
and the URLs are listed here for your convenience.

- DB_DataObject http://pear.php.net/package/DB_DataObject
- Validate http://pear.php.net/package/Validate
- OpenID by Janrain, http://janrain.com/openid-enabled/
- PEAR DB. Although this is an older data access system (new
  packages should use PDO), the OpenID libraries depend on PEAR DB
  or MDB2.
- OAuth.php from http://oauth.googlecode.com/svn/code/php/
- markdown.php from http://michelf.com/projects/php-markdown/
- PEAR Mail, for sending out mail notifications
  http://pear.php.net/package/Mail
- PEAR Net_SMTP, if you use the SMTP factory for notifications
  http://pear.php.net/package/Net_SMTP
- PEAR Net_Socket, if you use the SMTP factory for notifications
  http://pear.php.net/package/Net_Socket
- XMPPHP, the follow-up to Class.Jabber.php. Probably the best XMPP
  library available for PHP. http://xmpphp.googlecode.com/. Note that
  as of this writing the version of this library that is available in
  the extlib directory is *significantly different* from the upstream
  version (patches have been submitted). Upgrading to the upstream
  version may render your StatusNet site unable to send or receive XMPP
  messages.
- Facebook library. Used for the Facebook application.
- PEAR Validate is used for URL and email validation.
- Console_GetOpt for parsing command-line options.
  predecessor to OStatus.
- HTTP_Request2, a library for making HTTP requests.
- PEAR Net_URL2 is an HTTP_Request2 dependency.

A design goal of GNU Social is that the basic Web functionality should
work on even the most restrictive commercial hosting services.
However, additional functionality, such as receiving messages by XMPP,
require that you be able to run long-running processes on your account.
In addition, posting by email require that you be able to install a mail
filter in your mail server.

Installation
============

Installing the basic GNU Social web component is relatively easy,
especially if you've previously installed PHP/MariaDB packages.

1. Unpack the tarball you downloaded on your Web server. Usually a
   command like this will work:

       tar zxf gnusocial-*.tar.gz

   ...which will make a gnusocial-x.y.z subdirectory in your current
   directory. (If you don't have shell access on your Web server, you
   may have to unpack the tarball on your local computer and FTP the
   files to the server.)

2. Move the tarball to a directory of your choosing in your Web root
   directory. Usually something like this will work:

       mv gnusocial-x.y.z /var/www/gnusocial

   This will often make your GNU Social instance available in the gnusocial
   path of your server, like "http://example.net/gnusocial". "social" or
   "blog" might also be good path names. If you know how to configure 
   virtual hosts on your web server, you can try setting up
   "http://social.example.net/" or the like.

   If you have "rewrite" support on your webserver, and you should,
   then please enable this in order to make full use of your site. This
   will enable "Fancy URL" support, which you can read more about if you
   scroll down a bit in this document.

3. Make your target directory writeable by the Web server.

       chmod a+w /var/www/gnusocial/

   On some systems, this will probably work:

       chgrp www-data /var/www/gnusocial/
       chmod g+w /var/www/gnusocial/

   If your Web server runs as another user besides "www-data", try
   that user's default group instead. As a last resort, you can create
   a new group like "gnusocial" and add the Web server's user to the group.

4. You should also take this moment to make your avatar, background, and
   file subdirectories writeable by the Web server. An insecure way to do
   this is:

       chmod a+w /var/www/gnusocial/avatar
       chmod a+w /var/www/gnusocial/background
       chmod a+w /var/www/gnusocial/file

   You can also make the avatar, background, and file directories
   writeable by the Web server group, as noted above.

5. Create a database to hold your site data. Something like this
   should work:

       mysqladmin -u "root" --password="rootpassword" create gnusocial

   Note that GNU Social should have its own database; you should not share
   the database with another program. You can name it whatever you want,
   though.

   (If you don't have shell access to your server, you may need to use
   a tool like phpMyAdmin to create a database. Check your hosting
   service's documentation for how to create a new MariaDB database.)

6. Create a new database account that GNU Social will use to access the
   database. If you have shell access, this will probably work from the
   MariaDB shell:

       GRANT ALL on gnusocial.*
       TO 'gnusocial'@'localhost'
       IDENTIFIED BY 'agoodpassword';

   You should change the user identifier 'gnusocial' and 'agoodpassword'
   to your preferred new database username and password. You may want to
   test logging in to MariaDB as this new user.

7. In a browser, navigate to the GNU Social install script; something like:

       http://social.example.net/install.php

   Enter the database connection information and your site name. The
   install program will configure your site and install the initial,
   almost-empty database.

8. You should now be able to navigate to your social site's main directory
   and see the "Public Timeline", which will probably be empty. You can
   now register new user, post some notices, edit your profile, etc.

Fancy URLs
----------

By default, GNU Social will use URLs that include the main PHP program's
name in them. For example, a user's home profile might be found at:

    http://example.net/gnusocial/index.php/gnusocial/fred

On certain systems that don't support this kind of syntax, they'll
look like this:

    http://example.net/gnusocial/index.php?p=gnusocial/fred

It's possible to configure the software so it looks like this instead:

    http://example.net/gnusocial/fred

These "fancy URLs" are more readable and memorable for users. To use
fancy URLs, you must either have Apache 2.x with .htaccess enabled and
mod_rewrite enabled, -OR- know how to configure "url redirection" in
your server (like lighttpd or nginx).

1. Copy the htaccess.sample file to .htaccess in your StatusNet
   directory.

2. Change the "RewriteBase" in the new .htaccess file to be the URL path
   to your GNU Social installation on your server. Typically this will
   be the path to your GNU Social directory relative to your Web root.
   If you are installing it in the root directory, leave it as '/'.

3. Add, uncomment or change a line in your config.php file so it says:

       $config['site']['fancy'] = true;

You should now be able to navigate to a "fancy" URL on your server,
like:

    http://example.net/gnusocial/main/register

If you changed your HTTP server configuration, you may need to restart
the server first.

If it doesn't work, double-check that AllowOverride for the GNU Social
directory is 'All' in your Apache configuration file. This is usually
/etc/httpd.conf, /etc/apache/httpd.conf, or (on Debian and Ubuntu)
/etc/apache2/sites-available/default. See the Apache documentation for
.htaccess files for more details:

    http://httpd.apache.org/docs/2.2/howto/htaccess.html

Also, check that mod_rewrite is installed and enabled:

    http://httpd.apache.org/docs/2.2/mod/mod_rewrite.html

Sphinx
------

To use a Sphinx server to search users and notices, you'll need to
enable the SphinxSearch plugin. Add to your config.php:

    addPlugin('SphinxSearch');
    $config['sphinx']['server'] = 'searchhost.local';

You also need to install, compile and enable the sphinx pecl extension for
php on the client side, which itself depends on the sphinx development files.

See plugins/SphinxSearch/README for more details and server setup.

SMS
---

StatusNet supports a cheap-and-dirty system for sending update messages
to mobile phones and for receiving updates from the mobile. Instead of
sending through the SMS network itself, which is costly and requires
buy-in from the wireless carriers, it simply piggybacks on the email
gateways that many carriers provide to their customers. So, SMS
configuration is essentially email configuration.

Each user sends to a made-up email address, which they keep a secret.
Incoming email that is "From" the user's SMS email address, and "To"
the users' secret email address on the site's domain, will be
converted to a notice and stored in the DB.

For this to work, there *must* be a domain or sub-domain for which all
(or most) incoming email can pass through the incoming mail filter.

1. Run the SQL script carrier.sql in your StatusNet database. This will
   usually work:

       mysql -u "statusnetuser" --password="statusnetpassword" statusnet < db/carrier.sql

   This will populate your database with a list of wireless carriers
   that support email SMS gateways.

2. Make sure the maildaemon.php file is executable:

       chmod +x scripts/maildaemon.php

   Note that "daemon" is kind of a misnomer here; the script is more
   of a filter than a daemon.

2. Edit /etc/aliases on your mail server and add the following line:

       *: /path/to/statusnet/scripts/maildaemon.php

3. Run whatever code you need to to update your aliases database. For
   many mail servers (Postfix, Exim, Sendmail), this should work:

       newaliases

   You may need to restart your mail server for the new database to
   take effect.

4. Set the following in your config.php file:

       $config['mail']['domain'] = 'yourdomain.example.net';

At this point, post-by-email and post-by-SMS-gateway should work. Note
that if your mail server is on a different computer from your email
server, you'll need to have a full installation of StatusNet, a working
config.php, and access to the StatusNet database from the mail server.


Queues and daemons
------------------

Some activities that StatusNet needs to do, like broadcast OStatus, SMS,
XMPP messages and TwitterBridge operations, can be 'queued' and done by
off-line bots instead.

Two mechanisms are available to achieve offline operations:

* New embedded OpportunisticQM plugin, which is enabled by default
* Legacy queuedaemon script, which can be enabled via config file.

### OpportunisticQM plugin

This plugin is enabled by default. It tries its best to do background
job during regular HTTP requests, like API or HTML pages calls.

Since queueing system is enabled by default, notices to be broadcasted
will be stored, by default, into DB (table queue_item).

Each time it can, OpportunisticQM will try to handle some of them.

This is a good solution whether you:

* have no access to command line (shared hosting)
* do not want to deal with long-running PHP processes
* run a low traffic GNU social instance

In other case, you really should consider enabling the queuedaemon for
performance reasons. Background daemons are necessary anyway if you wish
to use the Instant Messaging features such as communicating via XMPP.

### queuedaemon

If you want to use legacy queuedaemon, you must be able to run
long-running offline processes, either on your main Web server or on
another server you control. (Your other server will still need all the
above prerequisites, with the exception of Apache.) Installing on a
separate server is probably a good idea for high-volume sites.

1. You'll need the "CLI" (command-line interface) version of PHP
   installed on whatever server you use.

   Modern PHP versions in some operating systems have disabled functions
   related to forking, which is required for daemons to operate. To make
   this work, make sure that your php-cli config (/etc/php5/cli/php.ini)
   does NOT have these functions listed under 'disable_functions':

       * pcntl_fork, pcntl_wait, pcntl_wifexited, pcntl_wexitstatus,
         pcntl_wifsignaled, pcntl_wtermsig

   Other recommended settings for optimal performance are:
       * mysqli.allow_persistent = On
       * mysqli.reconnect = On

2. If you're using a separate server for queues, install StatusNet
   somewhere on the server. You don't need to worry about the
   .htaccess file, but make sure that your config.php file is close
   to, or identical to, your Web server's version.

3. In your config.php files (both the Web server and the queues
   server!), set the following variable:

       $config['queue']['enabled'] = true;
       $config['queue']['daemon'] = true;

   You may also want to look at the 'daemon' section of this file for
   more daemon options. Note that if you set the 'user' and/or 'group'
   options, you'll need to create that user and/or group by hand.
   They're not created automatically.

4. On the queues server, run the command scripts/startdaemons.sh.

This will run the queue handlers:

* queuedaemon.php - polls for queued items for inbox processing and
  pushing out to OStatus, SMS, XMPP, etc.
* imdaemon.php - if an IM plugin is enabled (like XMPP)
* other daemons, like TwitterBridge ones, that you may have enabled

These daemons will automatically restart in most cases of failure
including memory leaks (if a memory_limit is set), but may still die
or behave oddly if they lose connections to the XMPP or queue servers.

It may be a good idea to use a daemon-monitoring service, like 'monit',
to check their status and keep them running.

All the daemons write their process IDs (pids) to /var/run/ by
default. This can be useful for starting, stopping, and monitoring the
daemons. If you are running multiple sites on the same machine, it will
be necessary to avoid collisions of these PID files by setting a site-
specific directory in config.php:

       $config['daemon']['piddir'] = __DIR__ . '/../run/';

It is also possible to use a STOMP server instead of our kind of hacky
home-grown DB-based queue solution. This is strongly recommended for
best response time, especially when using XMPP.

Themes
------

Older themes (version 0.9.x and below) no longer work with StatusNet
1.0.x, due to major changes in the site layout. We ship with three new
themes for this version, 'neo', 'neo-blue' and 'neo-light'.

As of right now, your ability to change the theme is site-wide; users
can't choose their own theme. Additionally, the only thing you can
change in the theme is CSS stylesheets and some image files; you can't
change the HTML output, like adding or removing menu items.

You can choose a theme using the $config['site']['theme'] element in
the config.php file. See below for details.

You can add your own theme by making a sub-directory of the 'theme'
subdirectory with the name of your theme. Each theme can have the
following files:

display.css: a CSS2 file for "default" styling for all browsers.
logo.png: a logo image for the site.
default-avatar-profile.png: a 96x96 pixel image to use as the avatar for
    users who don't upload their own.
default-avatar-stream.png: Ditto, but 48x48. For streams of notices.
default-avatar-mini.png: Ditto ditto, but 24x24. For subscriptions
    listing on profile pages.

You may want to start by copying the files from the default theme to
your own directory.

Translation
-----------

Translations in StatusNet use the gettext system <http://www.gnu.org/software/gettext/>.
Theoretically, you can add your own sub-directory to the locale/
subdirectory to add a new language to your system. You'll need to
compile the ".po" files into ".mo" files, however.

Contributions of translation information to StatusNet are very easy:
you can use the Web interface at translatewiki.net to add one
or a few or lots of new translations -- or even new languages. You can
also download more up-to-date .po files there, if you so desire.

For info on helping with translations, see http://status.net/wiki/Translations

Backups
-------

There is no built-in system for doing backups in StatusNet. You can make
backups of a working StatusNet system by backing up the database and
the Web directory. To backup the database use mysqldump <http://ur1.ca/7xo>
and to backup the Web directory, try tar.

Private
-------

The administrator can set the "private" flag for a site so that it's
not visible to non-logged-in users. (This is the default for new installs of version 1.0!)

This might be useful for workgroups who want to share a social
networking site for project management, but host it on a public
server.

Total privacy is attempted but not guaranteed or ensured. Private sites
currently don't work well with OStatus federation.

Access to file attachments can also be restricted to logged-in users only.

1. Add a directory outside the web root where your file uploads will be
   stored. Usually a command like this will work:

       mkdir /var/www/statusnet-files

2. Make the file uploads directory writeable by the web server. An
   insecure way to do this is:

       chmod a+x /var/www/statusnet-files

3. Tell StatusNet to use this directory for file uploads. Add a line
   like this to your config.php:

       $config['attachments']['dir'] = '/var/www/statusnet-files';