Solr and WordPress (instructions/howto)

This is for Tomcat5.5 (on Debian Lenny), WordPress 3.1 and Solr 3.4. The intention is to use the solr-for-wordpress plugin (see github ).

Lenny does include a Solr package (v1.2) which is somewhat outdated (and not supported by the upstream solr-for-wordpress wordpress plugin, hence we can’t use it).

Install Tomcat (and Java)

apt-get install sun-java6-jre

Edit /etc/profile and set a JAVA_HOME – so add in something like :

# Setup Jave environment 6
export PATH=$PATH:/usr/lib/jvm/java-6-sun/bin
export JAVA_HOME=/usr/lib/jvm/java-6-sun
export JRE_HOME=/usr/lib/jvm/java-6-sun/jre

And then do :

. /etc/profile
So those settings are set / present within your environment (or logout and back in).

Next, install Tomcat :

apt-get install tomcat5.5
and then
apt-get install tomcat5.5-admin

Configure Tomcat

Edit /etc/tomcat5.5/tomcat-users.xml and define your own user; for the -admin apps you’ll need to give the user a role of admin and manager.

e.g.

<?xml version='1.0' encoding='utf-8'?>
<tomcat-users>
  <role rolename="manager"/>
  <role rolename="tomcat"/>
  <role rolename="admin"/>
  <role rolename="role1"/>
  <user username="palepurple" password="letmein" roles="admin,manager,tomcat"/>
</tomcat-users>

And then restart Tomcat. You should now be able to visit http://yourserver:8180/admin and see a login screen.

In my case, I also edited /etc/tomcat5.5/server.xml to disable the AJP connector on port 8009 and also to tell the remaining connector (port 8180) to listen only on 127.0.0.1. To connect to the admin interface, I just use SSH port forwarding from my desktop – this is just to improve security.

Finally, it seems necessary to grant permission for Java to log to /var/log/tomcat5.5… .a dirty way of achieving this is to edit :

/etc/java-6-sun/security/java.policy

and add in (near the top)

grant {
	permission java.security.AllPermission;
};

(Yes, I know this is a bit like doing chmod -R 777 on a filesystem or something; but in my case Solr is running only on localhost, so I think it’s an acceptable fix; I’m sure Google can provide more eloquent fixes.).

 

Installing Solr

Download; unpack and install .war file :

cd /root
wget http://www.apache.org/dist/lucene/solr/3.4.0/apache-solr-3.4.0.tgz
tar -zxf apache-solr-3.4.0.tgz
cp apache-solr-3.4.0/dist/apache-solr-3.4.0.war /var/lib/tomcat5.5/webapps

If you now restart Solr, you’ll find some log files and stuff of use in /var/log/tomcat5.5 – looking in the catalina log file there you’ll see it moaning about not finding solrconfig.xml and so on. To fix this –

cp -a apache-solr-3.4.0/example/solr /var/lib/tomcat5.5/

And edit /etc/default/tomcat55 to contain :

export JAVA_OPTS="$JAVA_OPTS -Dsolr.solr.home=/var/lib/tomcat5.5/solr"

This tells Solr where to find it’s configuration and so on.

Then edit :

/var/lib/tomcat5.5/solr/conf/solrconfig.xml and fix the file paths to the various .jar files included – so in my case (you might want to copy them out of the apache-solr-3.4.0 dir and into /var/lib/tomcat5.5/solr/lib perhaps) – part of the solrconfig.xml is below :

  <lib dir="/var/lib/tomcat5.5/apache-solr-3.4.0/contrib/extraction/lib" />
  <!-- When a regex is specified in addition to a directory, only the
       files in that directory which completely match the regex
       (anchored on both ends) will be included.
    -->
  <lib dir="/var/lib/tomcat5.5/apache-solr-3.4.0/dist/" regex="apache-solr-cell-\d.*\.jar" />
  <lib dir="/var/lib/tomcat5.5/apache-solr-3.4.0/dist/" regex="apache-solr-clustering-\d.*\.jar" />
  <lib dir="/var/lib/tomcat5.5/apache-solr-3.4.0/dist/" regex="apache-solr-dataimporthandler-\d.*\.jar" />

  <!-- If a dir option (with or without a regex) is used and nothing
       is found that matches, it will be ignored
    -->
  <lib dir="/var/lib/tomcat5.5/apache-solr-3.4.0/contrib/clustering/lib/" />

Next create the data directory for solr to use :

mkdir /var/lib/tomcat5.5/solr/data
chown tomcat55 /var/lib/tomcat5.5/solr/data

And restart tomcat.

At this point you should be able to visit :

http://localhost:8180/apache-solr-3.4.0/admin/

If it fails, check out /var/log/tomcat5.5/*catalina.log* or /var/log/daemon.log

WordPress stuff

cd /path/to/wordpress/wp-content/plugins

git clone https://github.com/mattweber/solr-for-wordpress.git

cp solr-for-wordpress/schema.xml /var/lib/tomcat5.5/solr/conf/

<<restart tomcat again; /etc/init.d/tomcat5.5. restart >>

Now you just need to enable the plugin from within wordpress and tell wordpress to index your posts and you’re off.

  1.  Enable plugin
  2. Goto settings -> solr options -> select single server; tell it to use localhost, port 8180 and under the path ‘/apache-solr-3.4.0’
  3.  Perform the ‘server ping’ check; and then tell WordPress you want to index your pages/posts etc as you see fit.

3 comments

  1. In the plugin readme, Matt seems to tell the user to move the schema.xml to the examples folder and overwrite the existing schema. Wasn’t sure which way was best.

  2. Hi, I am trying to integrate solr search in wordpress but not for site wide search or posts search, but search and display results from a CSV/json/XML file. I created a wordpress form where on submit makes a Ajax call to Solr to fetch the results.

    This is not happening. Could you please help me with this.

    Thank you

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