martlark/pg_dump

Postgres Docker image with pg_dump running as a cron task. Find the image here: https://hub.docker.com/repository/docker/martlark/pg_dump

Usage

Import a postgreSQL database into this container and mount a volume to the containers /dump folder. Backups will appear in this volume. Optionally set up cron job schedule (default is 0 1 * * * - runs every day at 1:00 am).

Environment Variables:

Variable	Alias	Required?	Default	Description
PGUSER	None	Optional	postgres	The user for accessing the database
POSTGRES_PASSWORD	PGPASSWORD	Optional	None	The password for accessing the database
POSTGRES_DB	PGDB	Optional	postgres	The name of the database
PGHOST	None	Optional	db/localhost	The hostname of the database. db is the default if RUN_DOUBLE, localhost otherwise
PGPORT	None	Optional	5432	The port for the database
CRON_SCHEDULE	None	Required	0 1 * * *	The cron schedule at which to run the pg_dump
RETAIN_COUNT	None	Optional	None	Optionally, a number to retain, delete older files
PREFIX	None	Optional	dump	Optionally, prefix for dump files
PGDUMP	None	Optional	/dump	Optionally, define a different location to dump your backups.
LOGFIFO	None	Optional	${PGDUMP}/cron.fifo	Location to write cron logs to.
PG_LOG	None	Optional	None	Optionally, set any value to view this env inside of the container
COMMAND	None	Optional	dump-cron	Options: dump dumps the database and exit, dump-cron creates a cron job and runs
RUN_DOUBLE	None	Optional	true	"true" does not enable the PostgreSQL database within this container, "false" does
POSTGRES_PASSWORD_FILE	None	Recomended	None	Location of the password file. Overrides POSTGRES_PASSWORD and PGPASSWORD

Optional Controls

By default, this container executes as the postgres user. Using a non-root user for your container is always a safer route and should be one of your first modifications. The POSTGRES_PASSWORD field can either be set via environment variable or via docker secrets. Again, for security reasons, it is always recommended to use docker secrets for security concerns. If using the docker secrets, set the POSTGRES_PASSWORD_FILE field, warning this overrides POSTGRES_PASSWORD and PGPASSWORD. An example secrets file can be found below in the docker-compose area. The default for PGHOST is dependant on if RUN_DOUBLE is set; if RUN_DOUBLE is "true" than "db" is the default, if RUN_DOUBLE is "false" than "localhost" is the default. PGPORT is the exposed port in the container, so it is recommended not to change this.

Docker Compose

Example of running with a single PostgreSQL container.

version: "3.9"
services:
   database:
     image: martlark/pg_dump:12.14
     container_name: postgres-backup
     volumes:
       - postgres-data:/data:rw
       - postgres-backup:/dump:rw
     environment:
       - PGDATA=/data     # Where the SQL DB will store itself & backups will dump
       - RETAIN_COUNT=1   # Keep this number of backups
       - RUN_DOUBLE=false # Run postgresDB as part of this container
       - POSTGRES_DB=postgres    # The name of the database to dump
       - CRON_SCHEDULE=0 3 * * * # Every day at 3am
       - POSTGRES_PASSWORD_FILE=/run/secrets/db_password # The password file
     restart: unless-stopped
     secrets:
       - db_password # Contains the PSQL password

volumes:
   postgres-data:
      external: true
   postgres-backup:
      external: true

secrets:
   db_password:
     file: db_password.txt

Secrets file:

PGPASSWORD=SumPassw0rdHere

Example of running with separate services.

version: "3.9"
services:
  database:
    image: postgres:12.14
    volumes:
      - ./persistent/data:/var/lib/postgresql/data
    environment:
      - POSTGRES_PASSWORD=SumPassw0rdHere
      - POSTGRES_DB=postgres
    restart: unless-stopped

  postgres-backup:
    image: martlark/pg_dump:12.14
    container_name: postgres-backup
    links:
      - database:db # Maps as "db"
    environment:
      - PGPASSWORD=SumPassw0rdHere
      - CRON_SCHEDULE=0 3 * * * # Every day at 3am
      - RETAIN_COUNT=1 # Keep this number of backups
    volumes:
      - ./persistent/data:/dump

Tagged versions

Versions available on docker hub are:

11.19 12.14 13.10 14.7 15.2``

latest is 15.2