Rahal's Blog

In this example we are going to learn how to start tomcat on system startup.

1. Add following shell script to /etc/init.d/tomcat

### BEGIN INIT INFO
# Provides:        solr
# Required-Start: $network
# Required-Stop:   $network
# Default-Start:   2 3 4 5
# Default-Stop:    0 1 6
# Short-Description: Start/Stop solr server
### END INIT INFO

PATH=/sbin:/bin:/usr/sbin:/usr/bin

start() {
   sh /opt/apache-tomcat-8.0.36/bin/startup.sh
}

stop() {
    sh /opt/apache-tomcat-8.0.36/bin/shutdown.sh
}

case $1 in
start|stop) $1;;
restart) stop; start;;
*) echo "Run as $0 <start|stop|restart>"; exit 1;;
esac

2. Make the script executable

 sudo chmod +x /etc/init.d/tomcat

3. List all the service and find your service in the list

service --status-all

The services that have a [+] - (service name) will start on boot. The ones with [-] - (service name) will not start on boot.

4. Starting a server

service tomcat start

5. Add service to automatic startup

sudo update-rc.d tomcat defaults

5. Remove service from automatic startup

sudo update-rc.d -f tomcat remove

 rm /etc/rc*/*tomcat

6. Ubuntu startup log can be found in following location

/var/log/boot.log

References:

https://wiki.debian.org/LSBInitScripts
http://www.jcgonzalez.com/linux-java-service-wrapper-example

Overview

This article explain how solr can be configured to fetch data from neo4j database.

Install "movie" sample database in neo4j (3.0.1)

Click "Favourite" icon (star mark)
Click on "Movie Graph" under "Example Graphs"
Run the automatically generated query ":play movie-graph"
Follow the instruction and create the database

Configuring Solr (6.0.0)

Create a core

You would need to create a core in order to be able to index and search.
To create a core use following command
solr create -c <name>
i.e. solr create -c Movie -d basic_configs

Note that new folder will create as /solr-6.0.0/server/solr/Movie . And solr interface would look like below.

Import solr-dataimporthandler jars

Add following entry to /solr-6.0.0/server/solr/Movie/conf/solrconfig.xml

<lib dir="${solr.install.dir:../../../..}/dist/" regex="solr-dataimporthandler-.*\.jar" />

Configure dataImportHandler as a requestHandler

Add following entry to /solr-6.0.0/server/solr/Movie/conf/solrconfig.xml

<requestHandler name="/dataimport" class="org.apache.solr.handler.dataimport.DataImportHandler">
    <lst name="defaults">
      <str name="config">db-data-config.xml</str>
    </lst>
</requestHandler>

Note: db-data-config.xml is responsible for data import handler configurations.

db-data-config.xml configurations

Create db-data-config.xml in /solr-6.0.0/server/solr/Movie/conf/ and add following content

Modify the managed-schema file

Add following fields to the /solr-6.0.0/server/solr/Movie/conf/managed-schema

    <uniqueKey>Title</uniqueKey>
    <field name="Tagline" type="string" indexed="true" stored="true"/>
    <field name="Title" type="string" indexed="true" stored="true"/>
    <field name="Released" type="string" indexed="true" stored="true"/>

Remove below two line segments

<field name="id" type="string" indexed="true" stored="true" required="true" multiValued="false" />

<uniqueKey>id</uniqueKey>

Add Neo4j JDBC and dependencies

Get neo4j jdbc and it's dependencies using following maven config.

<dependencies>
     <dependency>
            <groupId>org.neo4j</groupId>
              <artifactId>neo4j-jdbc</artifactId>
              <version>2.0.0-M06</version>
      </dependency>
</dependencies>

<repositories>
        <repository>
          <id>neo4j-public</id>
          <url>http://m2.neo4j.org/content/groups/public</url>
        </repository>
    </repositories>

You can find required dependencies using eclipse IDE and by creating a maven project using above maven config.

So following are the required jars.

httpclient-4.3.2.jar
httpcore-4.3.1.jar
httpmime-4.3.jar
jackson-core-asl-1.9.12.jar
jackson-mapper-asl-1.9.12.jar
neo4j-cypher-dsl-1.9.RC2.jar
neo4j-jdbc-2.0.0-M06.jar
org.restlet-2.2.2.jar
org.restlet.ext.httpclient-2.2.2.jar

Importing the data

Use solr interface to import data as follows