Heroku Review Apps: copy DB to review app - postgresql

Question

Trying to fully automate Heroku's Review Apps (beta) for an app. Heroku wants us to use db/seeds.rb to seed the recently spun up instance's DB.
We don't have a db/seeds.rb with this app. We'd like to set up a script to copy the existing DB from the current parent (staging) and use that as the DB for the new app under review.
This I can do manually:
heroku pg:copy myapp::DATABASE_URL DATABASE_URL --app myapp-pr-1384 --confirm myapp-pr-1384
But I can't get figure out how to get the app name that Heroku creates into the postdeploy script.
Anyone tried this and know how it might be automated?

Answer 1

I ran into this same issue and here is how I solved it.
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.
In your app.json file make sure to copy that variable over.
In your app.json provision a new database which will set the DATABASE_URL environment variable.
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"
}
]
}

Answer 2

An alternative is to share the database between review apps. You can inherit DATABASE_URL in your app.json file.
PS: This is enough for my case which is a small team, keep in mind that maybe is not enough for yours. And, I keep my production and test (or staging, or dev, whatever you called it) data separated.

Answer 3

Alternatively:
Another solution using pg_restore, thanks to
https://gist.github.com/Kalagan/1adf39ffa15ae7a125d02e86ede04b6f
{
"scripts": {
"postdeploy": "pg_dump -Fc $DATABASE_URL_TO_COPY | pg_restore --clean --no-owner -n public -d $DATABASE_URL && bundle exec rails db:migrate"
}
}

Answer 4

I ran into problem after problem trying to get this to work. This postdeploy script finally worked for me:
pg_dump -cOx $STAGING_DATABASE_URL | psql $DATABASE_URL && bundle exec rails db:migrate

Answer 5

I see && bundle exec rails db:migrate as part of the postdeploy step in a lot of these responses.
Should that actually just be bundle exec rails db:migrate in the release section of app.json?