Prerequisite:
- Java 6 or higher

Steps necessary:
- Download Solr PHP client
- Setting up Solr

Download Solr PHP client
------------------------

This module uses an external PHP library for communicating with Solr servers. Go
to [1] and download version r60 of this library. (The older version r22 is also
still supported, but this might change in the future.)

[1] http://code.google.com/p/solr-php-client/downloads/list

Afterwards, unpack this archive to Drupal's libraries folder, so the directory
tree looks like this:

DRUPAL_ROOT/sites/all/libraries/
  |- SolrPhpClient
     |- Apache/
     |- ChangeLog
     ...

The library should then be found by the module.

Note: If you have the Libraries API [2] module installed, you can also place the
library into any other directory recognized by the Libraries API, e.g.
(depending on the module version):
- DRUPAL_ROOT/libraries
- DRUPAL_ROOT/profiles/PROFILE/libraries
- DRUPAL_ROOT/sites/CONF_DIR/libraries

[2] http://drupal.org/project/libraries

Setting up Solr
---------------

In order for this module to work, you will first need to set up a Solr server.
For this, you can either purchase a server from a web Solr hosts or set up your
own Solr server on your web server (if you have the necessary rights to do so).
If you want to use a hosted solution, a number of companies are listed on the
module's project page [3]. Otherwise, please follow the instructions below.

[3] http://drupal.org/project/search_api_solr

Download the latest version of Solr 3.x from [4] and unpack the archive
somewhere outside of your web server's document tree.

[4] http://www.apache.org/dyn/closer.cgi/lucene/solr/

This module also supports Solr 1.4, but its use is discouraged due to worse
performance and some features not being supported. Solr 4.x is not supported by
this module yet.

For small websites, using the example application, located in $SOLR/example/,
usually suffices. In any case, you can use it for developing andd testing. The
following instructions will assume you are using the example application,
otherwise you should be able to substitute the corresponding paths.

Before starting the Solr server you will have to make sure it uses the proper
configuration files. These are located in the solr-conf/ directory in this
module, in a sub-directory according to the Solr version you are using. Copy all
the files from that directory into Solr's configuration directory
($SOLR/example/solr/conf/ in case of the example application), after backing up
all files that would be overwritten.
You can then start Solr. For the example application, go to $SOLR/example/ and
issue the following command (assuming Java is correctly installed):

java -jar start.jar

Afterwards, go to [5] in your web browser to ensure Solr is running correctly.

[5] http://localhost:8983/solr/admin/

You can then enable this module and create a new server, using the "Solr search"
service class. Enter the hostname, port and path corresponding to your Solr
server in the appropriate fields. The default values already correspond to the
example application, so you won't have to change the values if you use that.
If you are using HTTP Authentication to protect your Solr server you also have
to provide the appropriate user and password here.