services:
  postgres:
    image: postgres:13
    environment:
      POSTGRES_USER: user
      POSTGRES_PASSWORD: password

  backup:
    image: eeshugerman/postgres-backup-s3:13
    environment:
      SCHEDULE: '@weekly'     # optional
      BACKUP_KEEP_DAYS: 7     # optional
      PASSPHRASE: passphrase  # optional
      S3_REGION: region
      S3_ACCESS_KEY_ID: key
      S3_SECRET_ACCESS_KEY: secret
      S3_BUCKET: my-bucket
      S3_PREFIX: backup
      POSTGRES_HOST: postgres
      POSTGRES_DATABASE: dbname
      POSTGRES_USER: user
      POSTGRES_PASSWORD: password

Images are tagged by the major PostgreSQL version they support: 10, 11, 12, 13, or 14.
The SCHEDULE variable determines backup frequency. See go-cron schedules documentation here. Omit to run the backup immediately and then exit.
If PASSPHRASE is provided, the backup will be encrypted using GPG.
Run docker exec <container name> sh backup.sh to trigger a backup ad-hoc
Use BACKUP_KEEP_DAYS to set time for how long you want to keep backup.

Restore

WARNING: DATA LOSS! All database objects will be dropped and re-created.

... from latest backup

docker exec <container name> sh restore.sh

NOTE: If your bucket has more than a 1000 files, the latest may not be restored -- only one S3 ls command is used

... from specific backup

docker exec <container name> sh restore.sh <timestamp>

Development

Build the image locally

ALPINE_VERSION determines Postgres version compatibility. See build-and-push-images.yml for the latest mapping.

docker build --build-arg ALPINE_VERSION=3.14

Run a simple test environment with Docker Compose

cp template.env .env
# fill out your secrets/params in .env
docker compose up -d

Acknowledgements

This project is a fork and re-structuring of @schickling's postgres-backup-s3 and postgres-restore-s3.

Fork goals

dedicated repository
automated builds
support multiple PostgreSQL versions
backup and restore with one image
support encrypted (password-protected) backups
option to restore from specific backup by timestamp
auto-removal old backups

Other changes

uses pg_dump's custom format (see docs)
doesn't use Python 2
backup blobs and all schemas by default
drop and re-create all database objects on restore
some env vars renamed or removed
filter backups on S3 by database name