Openshift provides us a lot of environment variables, we should use them whenever possible, so that we don't have to hard code anything in our code.

The following two env variables can helps us connect to mongodb easily

• OPENSHIFT_APP_NAME the name of your current app, for instance foo
• OPENSHIFT_MONGODB_DB_URL the full address of mongodb server, which looks like mongodb://admin:abcdefg@127.1.2.3:27017/

The complete connection string will be

OPENSHIFT_MONGODB_DB_URL + OPENSHIFT_APP_NAME

=> mongodb://admin:abcdefg@127.1.2.3:27017/foo

Pass the connection string to your mongodb client, and you should be able to use mongodb on Openshift!