script for running pg_dump against a container

docker_pg_dump.sh

#!/bin/bash
#docker_pg_dump.sh

# Thanks to StackOverflow answer by Forth
# https://stackoverflow.com/questions/24718706/backup-restore-a-dockerized-postgresql-database/29913462#29913462

HELP_MSG="
docker_pg_dump:
  Call pg_dump on RUNNING docker container.

  NOTE: Docker Must be installed & the postgres container must be running.
  container & user are required arguments.

ARGUMENTS:
  --container | -c
    Running container to exec against.

  --user | -u
    Postgres user to use with pg_dump.

  --gzip | -z
  Zip results with gzip. (Default=False)

EXAMPLE:
  docker_pg_dump.sh -c some-container-name -u postgres
"

while [ $# -gt 0 ]; do
  case "$1" in
    --container*|-c*)
      if [[ "$1" != *=* ]]; then shift; fi # Value is next arg if no `=`
      CONTAINER="${1#*=}"
      ;;
    --user*|-u*)
      if [[ "$1" != *=* ]]; then shift; fi
      USER="${1#*=}"
      ;;
    --gzip*|-z*)
      if [[ "$1" != *=* ]]; then shift; fi
      # GZIP="${1#*=}"
      GZIP=true
      ;;
    --help|-h)
      echo "$HELP_MSG" # Flag argument
      exit 0
      ;;
    *)
      >&2 printf "Error: Invalid argument\n"
      exit 1
      ;;
  esac
  shift
done

# not fool proof, we're checking variables instead of arguments
if [[ -z ${CONTAINER} || -z ${USER} ]]
then
  echo "ERROR: Missing Arguments. Please review help with --help | -h"
  exit 1
fi


# here's the money
if [[ $GZIP = true ]]
then
  docker exec -t $CONTAINER pg_dumpall -c -U $USER | gzip > dump_`date +%d-%m-%Y"_"%H_%M_%S`.gz
else
  docker exec -t $CONTAINER pg_dumpall -c -U $USER > dump_`date +%d-%m-%Y"_"%H_%M_%S`.sql
fi


# restore - update later
# cat your_dump.sql | docker exec -i your-db-container psql -U postgres