Create database backup from within Heroku Bash

Question

I want to periodically archive database dumps to my own AWS account in S3 and eventually in glacier. Is there a way to dump a postgresql database to the dynos filesystem from within the dyno (from where I then can send the file to AWS)? psql and pg_dump don't seem to be available on the dyno and I don't know how to run pgbackups from within a dyno.

Answer 1

The best I could come up with now is using the pgbackups addon (which I had been using) and then daily pulling the latest backup from s3 and uploading it back up to my bucket. A PGBACKUPS_URL env variable is exposed by Heroku if this addon is enabled. The rest would go something like this:

    # boto and requests are required, aws access credentials are in the settings file 

    url = settings.PGBACKUPS_URL + "/latest_backup"
    dumpfile = "./db_dump"

    # get latest backup info
    r = requests.get(url)
    dump_url = r.json()["public_url"]
    dump_timestamp = r.json()["finished_at"].replace("/", "-")
    dump_name = "db_dumps/" + dump_timestamp

    # write dump to file
    r = requests.get(dump_url, stream=True)
    if r.status_code == 200:
        with open(dumpfile, 'wb') as f:
            for chunk in r.iter_content():
                f.write(chunk)

    conn = S3Connection(settings.AWS_ACCESS_KEY_ID, settings.AWS_SECRET_ACCESS_KEY)
    bucket = conn.get_bucket(settings.AWS_DB_DUMPS_BUCKET)
    key = bucket.new_key(dump_name)
    key.set_contents_from_filename(dumpfile)

I have yet to find out, wether a backup can be triggered somehow via the PGBACKUPS_URL.

Answer 2

Create a separate heroku app to do the backups, which uses the pgbackups-archive gem and then set up a heroku scheduler to run the pgbackups-archive gem periodically on your DATABASE_URL (you will need to import that environment variable from your other app), as described here.

Disclaimer: this nominally requires you to use some ruby, but works in conjunction with any heroku cedar app using heroku postgres (including django apps).