INSTALL.txt in Domain Access 6.2

INSTALL file for Domain Access.

File

INSTALL.txt

/**
 * @file
 * INSTALL file for Domain Access.
 */

Domain Access
A domain-based access control system.

CONTENTS
--------

1.  Introduction
2.  Installation
2.1   Before Installing
2.2   Server Configuration
2.3   Setting DOMAIN_INSTALL_RULE
2.4   Setting DOMAIN_SITE_GRANT
2.5   Setting DOMAIN_ASSIGN_USERS
3.   Installing the Module
3.1   After Installation
4.  Configuring settings.php
4.1   $base_url
4.2   $db_prefix
4.3   $cookie_domain
4.4   Add settings.inc
4.4.1   Installation
4.4.2   Option 1
4.4.3   Option 2
4.4.4   Testing Your Configuration
4.4.5   Additional Resources
4.5 custom_url_rewrite_outbound()
5.  Additional Module Installation
5.1   Domain Strict
6.  Uninstalling

----
1.  Introduction

The Domain Access module is a Node Access module.  It is designed to
restrict access to content.

WARNINGS:
 - Failure to install or uninstall this module according to instructions
   may cause errors in your site.
 - Node Access rules never apply to user 1 (the site admin) or to users
   with the 'administer nodes' permission. As such, these users will always
   be able to see all content on your site(s). To verify that Domain Access
   is working correctly, you will need to turn on its debug mode or view the
   site as a user without this permission. You may also enable the 'Enforce
   rules on adminstrators' setting, which will apply Domain Access
   restrcitions to all users. (See section 4.3.3 of README.txt for more
   details on this feature.)

----
2.  Installation

This module requires some advanced understanding of Drupal and of
how DNS servers behave.  If you simply untar the download and
activate the module, it may not work correctly.

Domain Access works by reading the inbound HTTP_HOST request
and serving content appropriate to the requested domain. For this to
work properly, all domains for your site must be routed to the same
Drupal installation on your webserver.

Domain Access was not designed to run on shared hosts, and you may need
assistance from your provider to make it work correctly.

For more background on DNS and virtual host configuration, please try the
following documentation:

For a general overview:
  - http://en.wikipedia.org/wiki/Virtual_hosting

In-depth documentation with many examples for specific situations:
  - http://httpd.apache.org/docs/2.0/vhosts/
  - http://httpd.apache.org/docs/2.0/vhosts/examples.html

When you enable the module, it will create a {domain} table in your Drupal
database.

On installation, all existing nodes on your site will be assigned to the default
(primary) domain for your web site as well as  to all subdomains.
In order to change this behavior, see sections 2.3 and 2.4 below.

----
2.1  Before Installing

You will need to do the following before you install the module.

  - Read this document
  - Configure your web server DNS records appropriately
  - Read the supplied README.txt
  - Install and configure Drupal normally.

WARNING: The Domain Access module series instructs you to add a
file include to your settings.php file.  Do not add this command until
after you have installed Drupal.

----
2.2   Server Configuration

For the module to work correctly, the DNS record of your server must accept
multiple DNS entries [most servers do]. Your new virtual host(s) must then
be correctly configured for your server.  In general, this involves small
additions to the hosts file and the httpd.conf file.

In order for the Apache server to find your virtual host(s), it absolutely
needs two pieces of information: the ServerName (hostname & port the server
uses to identify itself) and an IP address.

The two basic methods for doing this are to either:

  - Set up WildCard DNS, so that *.example.com resolves to your Drupal site.
    (The asterisk indicates any and all names carrying the < example.com >
    suffix)
  - Set up each VirtualHost specifically, so that one.example.com,
    two.example.com, (and so on) all resolve to your Drupal site.

For example, on a local testing machine, VirtualHosts in my hosts file could be
configured in the following way:

  - ken.test => 127.0.0.1
  - one.ken.test => 127.0.0.1
  - two.ken.test => 127.0.0.1
  - foo.test => 127.0.0.1

With their port and document root defined (WildCard set up) in the httpd.conf
file:


DocumentRoot /path/to/drupal/install
ServerName ken.test
ServerAlias *.ken.test foo.test


In this case any subdomain (*.ken.test) and another domain foo.test resolve to
the same location. When configuring DNS for Domain Access, the document root is
the same for all the VirtualHosts. The documentRoot directive sets the directory
from which httpd will serve files. For DA, there is one Drupal installation and
it is this installation built on a single database that is serving the files.

This becomes even clearer when the VirtualHosts are set up specifically,
each with its own VirtualHost block in the httpd.conf file, for example:


DocumentRoot /path/to/drupal/install
ServerName ken.test



DocumentRoot /path/to/drupal/install
ServerName two.ken.test



DocumentRoot /path/to/drupal/install
ServerName foo.test


This example gives a general idea of what is involved, but it is beyond the
scope of this document to explain how to configure your specific DNS server
situation, which may involve considerable research, trial & error or a call for
help. Shared server situations can be particularly complicated and you should
contact their administration for help with configuration if their online help
files do not make things clear enough.

After you have enabled multiple DNS entries to resolve to your single,
default Drupal installation, you may activate the module and configure its
settings at Admin > Build > Domains.

----
2.3 Setting DOMAIN_INSTALL_RULE

This is an advanced instruction, and may be ignored.

At the top of the domain.module file, you will find this line:

  define('DOMAIN_INSTALL_RULE', TRUE);

This setting controls the default behavior of the module when installing over
an existing installation.  If set to TRUE, the Domain Access module will assign
all existing nodes to be viewable by your primary domain.

If you set this value to FALSE, existing content will not be visible on your
primary domain unless DOMAIN_SITE_GRANT is set to TRUE.

For more details, see section 5 of README.txt.

----
2.4 Setting DOMAIN_SITE_GRANT

At the top of the domain.module file, you will find this line:

  define('DOMAIN_SITE_GRANT', TRUE);

This setting controls the default behavior for viewing affiliate content.
By design, the Domain Access module allows site administrators to assign
content to 'all affiliates.'  If this value is set to TRUE, then content
assigned to all affiliates can be seen by all users on all current domains.

On install, setting this value to TRUE will assign all current content to
be viewable on all domains.

Normally, you will not need to edit this value.

----
2.5 Setting DOMAIN_ASSIGN_USERS

At the top of the domain.module file, you will find this line:

  define('DOMAIN_ASSIGN_USERS', TRUE);

After you install the Domain Access module, all new users who
register will automatically be assign to the domain from which
their account was created. This value is used to determine
advanced editing access and can be used by modules such as
Domain Strict.

On install, setting this value to TRUE will assign all current users
to be members of the default domain. Set the value to FALSE
and the module will not assign users to any domains.

Normally, you will not need to edit this value.

After installation and configuration, users with the appropriate
permissions may batch assign users to domains from
Administer > User Management > Users.

----
3.   Installing the Module

After you have prepared your server and made any edits to the
default module behavior, you may install Domain Access like any
other Drupal module.

----
3.1   After Installation

Note that as of 6.x.2.0, the primary domain is created for you on
installation.

The primary domain will use the SERVER_NAME value of the request made
when installing the module. This value may be edited by going to
Admin > Build > Domains and editing the Primary Domain value.

After you install the module, you should visit Admin > Users > Permissions
and set the module permissions; normally you will give your site
administrators the following permissions:

    -- 'administer domains'
    -- 'set domain access'

After saving permissions, go to Admin > Build > Domains and configure
your site's Primary Domain.

For more information, see README.txt.

----
4.  Configuring settings.php

Remember, the Domain Access module lets you run multiple sites
from a single installation.  You only need one settings.php file.

As a result, some options in your settings.php file need to be
considered carefully.

----
4.1   $base_url

The $base_url setting is normally not set.  With Domain Access, you
cannot set this value manually.

Since multiple domains are involved, Drupal needs to be allowed to
set this value.  (For the technical, this happens in the conf_init()
function).

If you need to install Drupal in a subdirectory and wish to hide that
subdirectory from site visitors, you may set $base_url dynamically.

See the instructions at http://drupal.org/node/633726.

----
4.2   $db_prefix

The $db_prefix value allows for table prefixing of your Drupal database
in the event that you run more than one site from a single database.

$db_prefix can be used normally with Domain Access.

However, the Domain Prefix module provides for dynamic table prefixing
based on the currently active domain. If you use the Domain Prefix module
you can set $db_prefix as a string value as well as an array.

For more detail, see INSTALL.txt in the domain_prefix folder.

----
4.3   $cookie_domain

By design, Drupal cookies are set for the current website on login.  That is, if
you login from www.example.com, the cookie will be set from the domain
'www.example.com.'

However, a cookie from www.example.com is not valid on one.example.com.

In order to provide for login across your active domains, you must set the
$cookie_domain value to the string indicating your root domain.

Typically, this value is '.example.com'.

If your domains do not share the top-level, then you may need to login to
each site separately or use a module such as Single SignOn.

NOTE: After you change your cookie value, you will need to logout and
log back in for the new cookie to take effect.

----
4.4  Add settings.inc

For Domain Access to work, you must add some code to your settings.php
file. This code will load the Domain Access bootstrap routines that determine
how your site is being requested.

If you do not add settings.inc to your settings.php file, Domain Access will
fail to load and report an error message to site administrators.

IMPORTANT: You must add these lines to settings.php after the $db_url
has been set; otherwise, Drupal will fail to load. Normally, you should add
these lines to the end of the settings.php file.

----
4.4.1  Installation

In the Domain Access download, find the following file:

  domain > settings.inc

You will need to load this file from inside your settings.php file. There
are two methods for this.

----
4.4.2  Option 1 -- Preferred

This method is preferred, since any updates to the module release
will be reflected in this file.

NOTE: the elements inside the ==== marks are php code that
should be copied into your settings.php file.  DO NOT COPY THE ==== MARKS.

Add the following lines to the end of your settings.php file:

====
/**
 * Add the domain module setup routine.
 */
include './path/to/modules/domain/settings.inc';
====

In this case, change 'path/to/modules' with the directory where your modules are
stored.  Typically this will be 'sites/all/modules', which makes the lines:

====
/**
 * Add the domain module setup routine.
 */
include './sites/all/modules/domain/settings.inc';
====

----
4.4.3 Option 2

If you are having difficulty determining the correct path, copy the following
files into your settings folder.

  domain > domain.bootstrap.inc
  domain > settings.inc
  domain > settings_custom_url.inc

The files should be in the same directory as your active settings.php file.
Then add the following lines:

====
/**
 * Add the custom_url_rewrite_outbound function.
 */
include 'settings.inc';
====

----
4.4.4   Testing Your Configuration

After editing your settings.php file, go to Admin > Build > Domains.  You may
see a warning at the top of the page:

  "Domain access failed to load during phase: bootstrap include. Please check your
  settings.php file and site configuration."

This message means that your PHP server cannot find the include file.  You
may need to test other path options for the include code.

When this occurs, the default domain will be loaded, but custom settings or
themes for other domains will not.

If the module is working correctly and you are getting persistent errors due to web
crawlers, you may disable this warning. To do so, edit settings.php and add the
following lines to the bottom of the file:

  $conf['domain_hide_errors'] = TRUE;

This will suppress the warning messages. See http://drupal.org/node/774692 for
background.

----
4.4.5   Additional Resources

If you are having trouble configuring the include, you should check your
PHP include path.  You may need to use an absolute path to your server root.

  http://us3.php.net/manual/en/ini.core.php#ini.include-path

You may also copy the entire function custom_url_rewrite_outbound() directly
into your settings.php file.

----
4.5 custom_url_rewrite_outbound()

custom_url_rewrite_outbound() is a special function that you can add
to settings.php to alter how Drupal writes links to content.

Domain Access implements this function within the context of the
URL Alter module, http://drupal.org/project/url_alter, which is a
functional backport of changes implemented in Drupal 7.

If your site uses custom code to implement custom_url_rewrite_outbound(),
consider upgrading to the URL Alter module for full compatibility.

You may also call the function domain_url_rewrite_outbound() directly in
your custom code.

NOTE: Domain Access does not use custom_url_rewrite_inbound().

For more information, see
  http://api.drupal.org/api/function/custom_url_rewrite_outbound/6
  http://drupal.org/node/450344
  http://drupal.org/node/529026

----
5.  Additional Module Installation

The Domain Access module includes several sub-modules.  Two of these
have their own INSTALL.txt instructions.

----
5.1   Domain Strict

While this module requires no additional installation, it fundamentally
changes the behavior of the Domain Access module.

Under Domain Strict, only authenticated users (those who have registered)
are given any domain-specific privileges.

Anonymous users will only be able to view content that is assigned to "all
affiliates."

As a result, enabling this module may cause content to disappear from your
site for users who are not logged in.  This is by design.

Refer to domain > domain_strict > README.txt

----
6.  Uninstalling

When you disable this module, it will reset your {node_access} tables and
remove all records from the {domain_access} table.  This will remove all
access rules associated with this module.

You may then uninstall the module normally.

You should also revert the patches that you applied and remove
any extra code from your settings.php file.

To revert a patch, see http://drupal.org/patch/reverse