leklund / heroku_db_env Goto Github PK

• Overwrite Heroku's auto generated database configuration

Add the gem to your gemfile

gem 'heroku_db_env'

Add your custom database configuation or overrides to the heroku_database.yml file. The format is identical to database.yml. The gem will also look for any environment variables in the format [env]_DATABASE_URL and merge the resulting connection hash into the database configuation.

Lets assume that you are running in your production environment and your DATABASE_URL is set to

postgres://user:pass@hostname/db_prod

Heroku's auto-generated database.yml is actually an ERB script which will transform the DATABASE_URL environment variable to the following connection config when the file is read

production:
  adapter: postgres
  database: db_prod
  username: user
  password: pass
  host: hostname

Now lets say, for whatever reason, you are unhappy with the auto generated database configuration. You can overwrite it by providing a heroku_database.yml file in your config directory and/or by specifying environment specific DATABASE_URL env vars.

In your heroku_database.yml

production:
  pool: 10

reporting:
  pool: 5
  schema_search_path: reporting_schema

And your REPORTING_DATABASE_URL is set to

postgres://user:[email protected]/db_reporting

The final database configuration should look like

production:
  adapter: postgres
  database: db_prod
  username: user
  password: pass
  host: hostname
  pool: 10
reporting:
  adapter: postgres
  database: db_reporting
  username: user
  password: pass
  host: reporting.hostname
  pool: 5
  schema_search_path: reporting_schema

Run a db rake task against any configured database to test the setup

heroku run rake db:migrate RAILS_ENV=reporting