Doradus on OpenShift

This is a Red Hat OpenShift prototype that demonstrates how to deploy and use Doradus (https://github.com/dell-oss/Doradus) deployed in one gear that connects to Cluster of Cassandra nodes on other gears on the same OpenShift broker.

Running on OpenShift

Create an OpenShift account at https://www.openshift.com

Set up the OpenShift Environment (https://developers.openshift.com/en/getting-started-client-tools.html)

Set up a cluster of 2 Cassandra nodes (using https://github.com/dell-oss/cassandra-instance) and note down the IP of 1 Cassandra node to use for CASSANDRA_NODE_IP below.

Create Doradus instance

rhc app create doradus diy

Check if the private IP of 1st cassandra instance can be reached from Doradus enviroment

ssh <to the gear of doradus>
curl http://<CASSANDRA_NODE_IP>:19042

(expect to see the message other than “curl: (7) couldn't connect to host”)
if you get that message, then you need to retry the step “Create Doradus instance” until Openshift gives you the environment that can connect to 1 of Cassandra nodes.

Config CQL cassandra node as part of the cluster above for Doradus

cd doradus

rhc env set CASSANDRA_NODE_IP=<CASSANDRA_NODE_IP> CASSANDRA_NODE_PORT=19042 DORADUS_STORAGE_SERVICE=com.dell.doradus.service.spider.SpiderService

Check the environment variables are set

rhc env-list

Add this upstream repo

git remote add upstream https://github.com/TraDuong1/doradus-cassandracluster-openshift
git pull -s recursive -X theirs upstream master

Then push the repo upstream

git push

Test

Doradus APIs
============

Invoke this URL to list all applications under Doradus
http://doradus-$yournamespace.$youropenshiftserver/_applications

For the first time, you should expect to see empty list.

Using Rest Client, post this XML schema to create a new application and its tables 
in Doradus via the URL above

 <application name="MyApplication"> 
        <key>Test123</key> 
        <options> 
            <option name="StorageService">SpiderService</option> 
        </options> 
        <tables> 
            <table name="Movies"> 
                <fields> 
                    <field name="Name" type="text"/> 
                    <field name="ReleaseDate" type="timestamp"/> 
                    <field name="Cancelled" type="boolean"/> 
                    <field name="Director" type="text"/> 
                    <field name="Leads" type="text" collection="true"/> 
                    <field name="Budget" type="integer"/> 
                </fields> 
            </table> 
        </tables> 
    </application>

Invoke the URL http://doradus-$yournamespace.$youropenshiftserver/_applications again to see the Doradus the application and its data.

Read more about REST APIs on the Doradus website.


Doradus High-availability
=========================

Bring down 1 of cassandra nodes

rhc app stop -a <cassandra_server1> 
or 
rhc app stop -a <cassandra_server2>

Verify http://doradus-$yournamespace.$youropenshiftserver/_applications still works


Restart the server

rhc app start -a <cassandra_server1>
or 
rhc app start -a <cassandra_server2>

Verify http://doradus-$yournamespace.$youropenshiftserver/_applications works