Neo4j server failed to start in openshift

Question

I want to create a social network in django framework in Openshift then I need at least a graph db (like Neo4j)and a relational db (like Mysql). I had trouble in add Neo4j to my project because openshift has not any cartridge for it. then I decide to install it with DIY, but I don't understand the functionality of start and stop files in .openshift/action hooks.Then I doing the following steps to install neo4j on server:

1.ssh to my account:

ssh 1238716...@something-prolife.rhcloud.com

2.go in a folder that have permission to write (I go to app-root/repo/ and mkdir test in it) and download the neo4j package from here. and extract it to the test folder that I created before :

tar -xvzf neo4j-community-1.9.4-unix.tar.gz

3.and finally run the neo4j file and start it:

neo4j-community-1.9.4/bin/neo4j start

but I see these logs and can't run the neo4j:

process [3898]... waiting for server to be ready............ Failed   
to start within 120 seconds.
Neo4j Server may have failed to start, please check the logs.

how can I run this database in openshift ? where I am wrong ? and where is the logs in please check the logs?

Answer 1

I've developed an openshift cartridge that fixes the permission issue in openshift. I had to change the class HostBoundSocketFactory and SimpleAppServer in neo4j just to bind without using the 0 port, but using an openshift available port.

You can check at: https://github.com/danielnatali/openshift-neo4j-cartridge

it's working for me.

Answer 2

There are 2 ways neo4j can run : embedded or standalone(exposed via a rest service).

Standalone is what you are trying to do. I think the right way to setup neo4j would be by writing a cartridge for openshift, and then add the cartridge to your gear. There has been some discussion about this, but it seems that nobody has taken the time to do this. Check https://www.openshift.com/forums/openshift/neo4j-cartridge. If you decide to write your own cartridge, i might assist. Here are the docs: https://www.openshift.com/developers/download-cartridges.

The other option is running in embedded mode, which i have used. You need to set up a Java EE application(because neo4j embedded mode libraries are available only with java), and put the neo4j libraries in your project. Then, you would expose some routes, check for parameters and run your neo4j queries inside the servlets.

Answer 3

I would also not place it in the app-root/repo but instead I would put it in app-root/data.

You also need to use the IP of the gear - I think the env. variable is something like OPENSHIFT_INTERAL_IP. 127.0.0.1 is not available for binding but I think the ports should be open.