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

pg_backup_s3:
  image: eeshugerman/postgres-backup-s3:13
  environment:
    SCHEDULE: '@weekly'
    PASSPHRASE: passphrase
    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
    BACKUP_KEEP_DAYS: 7 // Disabled by default.

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>

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