backup.sh

#! /bin/sh

# shellcheck disable=SC3040  # expecting 'pipefail' derrictive is availabe in the shell
# shellcheck disable=SC2086  # POSTGRES_HOST_OPTS and AWS_ARGS should be splitted by spaces intentionally

set -e
set -o pipefail

if [ "${S3_ACCESS_KEY_ID}" = "**None**" ]; then
  echo "You need to set the S3_ACCESS_KEY_ID environment variable."
  exit 1
fi

if [ "${S3_SECRET_ACCESS_KEY}" = "**None**" ]; then
  echo "You need to set the S3_SECRET_ACCESS_KEY environment variable."
  exit 1
fi

if [ "${S3_BUCKET}" = "**None**" ]; then
  echo "You need to set the S3_BUCKET environment variable."
  exit 1
fi

if [ "${POSTGRES_DATABASE}" = "**None**" ]; then
  echo "You need to set the POSTGRES_DATABASE environment variable."
  exit 1
fi

if [ "${POSTGRES_HOST}" = "**None**" ]; then
  if [ -n "${POSTGRES_PORT_5432_TCP_ADDR}" ]; then
    POSTGRES_HOST="${POSTGRES_PORT_5432_TCP_ADDR}"
    POSTGRES_PORT="${POSTGRES_PORT_5432_TCP_PORT}"
  else
    echo "You need to set the POSTGRES_HOST environment variable."
    exit 1
  fi
fi

if [ "${POSTGRES_USER}" = "**None**" ]; then
  echo "You need to set the POSTGRES_USER environment variable."
  exit 1
fi

if [ "${POSTGRES_PASSWORD}" = "**None**" ]; then
  echo "You need to set the POSTGRES_PASSWORD environment variable or link to a container named POSTGRES."
  exit 1
fi

if [ "${S3_ENDPOINT}" = "**None**" ]; then
  AWS_ARGS=""
else
  AWS_ARGS="--endpoint-url ${S3_ENDPOINT}"
fi

# env vars needed for aws tools
export AWS_ACCESS_KEY_ID="${S3_ACCESS_KEY_ID}"
export AWS_SECRET_ACCESS_KEY="${S3_SECRET_ACCESS_KEY}"
export AWS_DEFAULT_REGION="${S3_REGION}"

export PGPASSWORD="${POSTGRES_PASSWORD}"
POSTGRES_HOST_OPTS="-h ${POSTGRES_HOST} -p ${POSTGRES_PORT} -U ${POSTGRES_USER} ${POSTGRES_EXTRA_OPTS}"

echo "Creating dump of ${POSTGRES_DATABASE} database from ${POSTGRES_HOST}..."

pg_dump -Fc ${POSTGRES_HOST_OPTS} "${POSTGRES_DATABASE}" > db.dump

echo "Uploading dump to ${S3_BUCKET}"

aws ${AWS_ARGS} s3 cp db.dump "s3://${S3_BUCKET}/${S3_PREFIX}/${POSTGRES_DATABASE}_$(date +"%Y-%m-%dT%H:%M:%SZ").dump" || exit 2

echo "DB backup uploaded successfully"

rm db.dump

if [ ! "${SUCCESS_WEBHOOK}" = "**None**" ]; then
    echo "Notifying ${SUCCESS_WEBHOOK}"
    curl -m 10 --retry 5 "${SUCCESS_WEBHOOK}"
fi