entrypoint.sh

#!/bin/bash
set -eo pipefail

# destination
: "${DESTINATION_KIND:?Please set the environment variable.}"
DESTINATION_KINDS=(s3 sftp)
if [[ ! " ${DESTINATION_KINDS[*]} " =~ " ${DESTINATION_KIND} " ]]; then
  printf "error: DESTINATION_KIND should be one of these: %s\n" "${DESTINATION_KINDS[*]}"
  exit 1
fi

# postgres
: "${POSTGRES_DB:?Please set the environment variable.}"
POSTGRES_HOST="${POSTGRES_HOST:-postgres}"
POSTGRES_PORT="${POSTGRES_PORT:-5432}"
POSTGRES_USER="${POSTGRES_USER:-postgres}"
POSTGRES_VERSION="${POSTGRES_VERSION:-18}"

POSTGRES_VERSIONS=(16 17 18)
if [[ ! " ${POSTGRES_VERSIONS[*]} " =~ " ${POSTGRES_VERSION} " ]]; then
  printf "error: POSTGRES_VERSION should be one of these: %s\n" "${POSTGRES_VERSIONS[*]}"
  exit 1
fi

# destination: s3
if [[ "${DESTINATION_KIND}" == "s3" ]]; then
  : "${S3_ACCESS_KEY_ID:?Please set the environment variable.}"
  : "${S3_REGION:?Please set the environment variable.}"
  : "${S3_SECRET_ACCESS_KEY:?Please set the environment variable.}"
  S3_PROVIDER="${S3_PROVIDER:-AWS}"
  S3_STORAGE_CLASS="${S3_STORAGE_CLASS:-STANDARD_IA}"
fi

# destination: sftp
if [[ "${DESTINATION_KIND}" == "sftp" ]]; then
  : "${SFTP_HOST:?Please set the environment variable.}"
  : "${SFTP_USER:?Please set the environment variable.}"
  SFTP_PORT="${SFTP_PORT:-22}"
  
  # Check if either password or private key is provided
  if [[ -z "${SFTP_PASSWORD}" && -z "${SFTP_PRIVATE_KEY}" ]]; then
    echo "error: Either SFTP_PASSWORD or SFTP_PRIVATE_KEY must be set for SFTP authentication"
    exit 1
  fi
  
  # Check that both are not provided
  if [[ -n "${SFTP_PASSWORD}" && -n "${SFTP_PRIVATE_KEY}" ]]; then
    echo "error: Only one of SFTP_PASSWORD or SFTP_PRIVATE_KEY should be set, not both"
    exit 1
  fi
fi

# logic starts here
BACKUP_FILE_NAME=$(date +"${POSTGRES_DB}-%F-%H_%M_%S.sql")

# dump command
DUMP_CMD=""
if [[ "${POSTGRES_PASSWORD}" != "" ]]; then
  DUMP_CMD+="PGPASSWORD=\"${POSTGRES_PASSWORD}\" "
fi
DUMP_CMD+="/usr/libexec/postgresql${POSTGRES_VERSION}/pg_dump "
DUMP_CMD+="--dbname=\"${POSTGRES_DB}\" "
DUMP_CMD+="--file \"${BACKUP_FILE_NAME}\" "
DUMP_CMD+="--format=c "
DUMP_CMD+="--host=\"${POSTGRES_HOST}\" "
DUMP_CMD+="--port=\"${POSTGRES_PORT}\" "
DUMP_CMD+="--username=\"${POSTGRES_USER}\" "

# upload command
UPLOAD_CMD="rclone copyto --config \"\" "
if [[ "${DESTINATION_KIND}" == "s3" ]]; then
  UPLOAD_CMD+="--s3-no-check-bucket "
fi
UPLOAD_CMD+="./${BACKUP_FILE_NAME} "
UPLOAD_CMD+="\""
if [[ "${DESTINATION_KIND}" == "s3" ]]; then
  UPLOAD_CMD+=":s3,access_key_id=${S3_ACCESS_KEY_ID},"
  UPLOAD_CMD+="provider=AWS,"
  UPLOAD_CMD+="region=${S3_REGION},"
  UPLOAD_CMD+="secret_access_key=${S3_SECRET_ACCESS_KEY},"
  UPLOAD_CMD+="storage_class=${S3_STORAGE_CLASS}"
  if [[ -n "${S3_ENDPOINT}" ]]; then
    UPLOAD_CMD+=",endpoint=${S3_ENDPOINT}"
  fi
  UPLOAD_CMD+=":${DESTINATION_PATH}/${BACKUP_FILE_NAME}"
elif [[ "${DESTINATION_KIND}" == "sftp" ]]; then
  UPLOAD_CMD+=":sftp,host=${SFTP_HOST},"
  if [[ -n "${SFTP_PASSWORD}" ]]; then
    # rclone requires passwords to be obscured using its own obscure command
    SFTP_PASSWORD_OBSCURED=$(echo "${SFTP_PASSWORD}" | rclone obscure -)
    UPLOAD_CMD+="pass=${SFTP_PASSWORD_OBSCURED},"
  elif [[ -n "${SFTP_PRIVATE_KEY}" ]]; then
    UPLOAD_CMD+="key_file=/tmp/sftp_private_key,"
  fi
  UPLOAD_CMD+="port=${SFTP_PORT},"
  UPLOAD_CMD+="user=${SFTP_USER}"
  UPLOAD_CMD+=":${DESTINATION_PATH}/${BACKUP_FILE_NAME}"
fi
UPLOAD_CMD+="\" "
UPLOAD_CMD+="--quiet"

# let's go
SECONDS=0

# create private key file if SFTP_PRIVATE_KEY is provided
if [[ "${DESTINATION_KIND}" == "sftp" && -n "${SFTP_PRIVATE_KEY}" ]]; then
  echo "${SFTP_PRIVATE_KEY}" | base64 -d > /tmp/sftp_private_key
  chmod 600 /tmp/sftp_private_key
fi

printf "Dumping the database..."
eval "${DUMP_CMD}"
printf " Done.\n"

printf "Uploading..."
eval "${UPLOAD_CMD}"
printf " Done.\n"

SECONDS_ON_COMPLETE="${SECONDS}"

if [[ -n "${WEBGAZER_HEARTBEAT_URL}" ]]; then
  printf "Sending heartbeat to WebGazer..."
  curl -Ssf -o /dev/null "${WEBGAZER_HEARTBEAT_URL}?seconds=${SECONDS_ON_COMPLETE}"
  printf " Done.\n"
fi

if [[ -n "${GATUS_EXTERNAL_ENDPOINT_TOKEN}" && -n "${GATUS_EXTERNAL_ENDPOINT_URL}" ]]; then
  printf "Sending heartbeat to Gatus..."
  curl \
    -X POST \
    -H "Authorization: Bearer ${GATUS_EXTERNAL_ENDPOINT_TOKEN}" \
    "${GATUS_EXTERNAL_ENDPOINT_URL}?success=true&duration=${SECONDS_ON_COMPLETE}s"
  printf " Done.\n"
fi

if [[ "${DESTINATION_KIND}" == "sftp" && -n "${SFTP_PRIVATE_KEY}" ]]; then
  rm -f /tmp/sftp_private_key
fi