prep-docker

#!/usr/bin/env bash

show_help() {
  cat <<'EOF'

prep-docker

Usage:
 prep-docker [options] <env-file> <out-dir>

Creates a Dockerfile file and a docker-compose.yml file that can be used to
build and run a container hosting an iRODS resource server configured to be
part of the CyVerse Data Store.

Parameters:
 <env-file>  the file providing the required environment variables, see below
 <out-dir>   the directory where the docker files will be written: defaults to
             current working directory

Options:
 -h, --help  show help and exit

Environment Variables:
 IRODS_CLERVER_USER  (optional) the name of the rodsadmin user representing the
                     resource server within the zone: default 'ipc_admin'
 IRODS_HOST_UID      (optional) the UID of the hosting server to run iRODS as
                     instead of the default user defined in the container
 IRODS_LOG_DIR       (optional) the absolute path on the server hosting the
                     container where iRODS will write its logs: default
                     '<home>/log' where <home> is the home directory of the user
                     starting the docker container
 IRODS_RES_SERVER    the FQDN or address used by the IES and other resource
                     servers to communicate with this one
 IRODS_RES_VAULT     (optional) the host directory where the container will
                     mount the vault: default '<home>/vault', where <home> is
                     the home directory of the user starting the dock
                     container
 IRODS_STORAGE_RES   the name of the storage resource that will be served
EOF
}

set -o errexit -o nounset -o pipefail

main() {
  local opts
  if ! opts=$(getopt --name prep-docker --options h --longoptions help -- "$@")
  then
    show_help >&2
    return 1
  fi

  eval set -- "$opts"

  while true
  do
    case "$1" in
      -h|--help)
        show_help
        return 0
        ;;
      --)
       shift
       break
       ;;
      *)
        show_help >&2
        return 1
        ;;
    esac
  done

  if [ "$#" -lt 1 ]
  then
    printf 'An environment file is required.\n' >&2
    show_help >&2
    return 1
  fi

  local envFile="$1"

  local outDir=.

  if [ "$#" -ge 2 ]
  then
    outDir="$2"

    if [ ! -e "$outDir" ]
    then
      mkdir --parents "$outDir"
    fi
  fi

  build "$envFile" "$outDir"
}

build() {
  local envFile="$1"
  local outDir="$2"

  # shellcheck disable=SC1090
  . "$envFile"
  check_env IRODS_STORAGE_RES
  check_env IRODS_RES_SERVER

  local defaultRes="$IRODS_STORAGE_RES"Res
  local hostVault="${IRODS_RES_VAULT:-\$HOME/vault}"
  local hostLog="${IRODS_LOG_DIR:-\$HOME/log}"
  local user="${IRODS_CLERVER_USER:-ipc_admin}"

  printf 'FROM cyverse/ds-irods-rs-onbuild:latest\n' > "$outDir"/Dockerfile
  mk_compose_file "$defaultRes" "$user" "$hostLog" "$hostVault" > "$outDir"/docker-compose.yml
}

#
# Checks for the existence of an environment variable. If the variable doesn't
# exist, it writes a message to standard error and returns 1.
#
# Parameter:
#  var  the environment variable to check
#
check_env() {
  local var="$1"

  if [ -z "${!var}" ]
  then
    printf 'The environment variable %s is not set.\n' "$var" >&2
    show_help >&2
    return 1
  fi
}

#
# Generate a script for starting a container from the newly build image.
#
# Parameters:
#  defaultRes  the name of the coordinating resource the server will use by
#              default
#  user        the name of the rodsadmin user the server will authenticate as
#  hostLog     the host directory where teh container will mount
#              /var/lib/irods/log
#  hostVault   the host directory where the container will mount its vault
#
mk_compose_file() {
  local defaultRes="$1"
  local user="$2"
  local hostLog="$3"
  local hostVault="$4"

  cat <<EOF
---
services:
  cyverse-rs:
    build:
      args:
        IRODS_CLERVER_USER: $user
        IRODS_DEFAULT_RES: $defaultRes
        IRODS_HOST_UID: $IRODS_HOST_UID
        IRODS_RES_SERVER: $IRODS_RES_SERVER
        IRODS_STORAGE_RES: $IRODS_STORAGE_RES
      context: .
    env_file: cyverse-secrets.env
    hostname: rs
    ports:
      - "1247:1247/tcp"
      - "1248:1248/tcp"
      - "20000-20009:20000-20009/tcp"
      - "20000-20009:20000-20009/udp"
    restart: on-failure
    sysctls:
      - net.ipv4.tcp_keepalive_time=120
    tmpfs: /var/lib/irods/log/proc:uid=$IRODS_HOST_UID
    tty: true
    volumes:
      - $hostVault:/irods_vault/$IRODS_STORAGE_RES
      - $hostLog:/var/lib/irods/log
      - /etc/timezone:/etc/timezone:ro
      - /etc/localtime:/etc/localtime:ro
EOF
}

main "$@"