Heroku Review Apps: copy DB to review app

I ran into this same issue and here is how I solved it.

1. Set up the database url you want to copy from as an environment variable on the base app for the pipeline. In my case this is STAGING_DATABASE_URL. The url format is postgresql://username:password@host:port/db_name.

2. In your app.json file make sure to copy that variable over.

3. In your app.json provision a new database which will set the DATABASE_URL environment variable.

4. Use the following script to copy over the database pg_dump $STAGING_DATABASE_URL | psql $DATABASE_URL

Here is my app.json file for reference:

{
  "name": "app-name",
  "scripts": {
    "postdeploy": "pg_dump $STAGING_DATABASE_URL | psql $DATABASE_URL && bundle exec rake db:migrate"
  },
  "env": {
    "STAGING_DATABASE_URL": {
      "required": true
    },
    "HEROKU_APP_NAME": {
      "required": true
    }
  },
  "formation": {
    "web": {
      "quantity": 1,
      "size": "hobby"
    },
    "resque": {
      "quantity": 1,
      "size": "hobby"
    },
    "scheduler": {
      "quantity": 1,
      "size": "hobby"
    }
  },
  "addons": [
    "heroku-postgresql:hobby-basic",
    "papertrail",
    "rediscloud"
  ],
  "buildpacks": [
    {
      "url": "heroku/ruby"
    }
  ]
}