Parse MongoDB connection string in bash

mongo-url.sh

#!/usr/bin/env bash

set -e
# Usage: parse_mongo_url URL
# It sets the following variables:
# MONGO_HOST
# MONGO_PORT
# MONGO_DATABASE
# MONGO_USER
# MONGO_PASSWORD
function parse_mongo_url {
  local MONGO_URL="$1"

  local AUTH
  local HOST_PORT
  local PROTO
  local URL

  PROTO="$(echo ${MONGO_URL} | grep :// | sed -e's,^\(.*://\).*,\1,g')"
  URL="${MONGO_URL/${PROTO}/}"

  AUTH="$(echo ${URL} | grep @ | rev | cut -d@ -f2- | rev)"
  if [ -n ${AUTH} ]; then
    URL="$(echo ${URL} | rev | cut -d@ -f1 | rev)"
  fi

  MONGO_PASSWORD="$(echo ${AUTH} | grep : | cut -d: -f2-)"
  if [ -n "${MONGO_PASSWORD}" ]; then
    MONGO_USER="$(echo ${AUTH} | grep : | cut -d: -f1)"
  else
    MONGO_USER=${AUTH}
  fi

  HOST_PORT="$(echo ${URL} | cut -d/ -f1)"
  MONGO_PORT="$(echo ${HOST_PORT} | grep : | cut -d: -f2)"
  if [ -n "${MONGO_PORT}" ]; then
    MONGO_HOST="$(echo ${HOST_PORT} | grep : | cut -d: -f1)"
  else
    MONGO_PORT=27017
    MONGO_HOST="${HOST_PORT}"
  fi

  MONGO_DATABASE="$(echo ${URL} | grep / | cut -d/ -f2-)"
}

mongo-url.test.sh

#!/usr/bin/env bash

set -e

function check_eq {
  local EXPECTED=$1
  local ACTUAL=$2
  local PREFIX=$3

  if [ "${EXPECTED}" != "${ACTUAL}" ]; then
      echo "${PREFIX}Check error. Expected: [${EXPECTED}], Actual: [${ACTUAL}]"
      exit 2
  fi
}

function check_mongo_url {
  local MONGO_URL=$1

  local TEST_USER=$2
  local TEST_PASSWORD=$3
  local TEST_HOST=$4
  local TEST_PORT=$5
  local TEST_DATABASE=$6

  local ERROR_PREFIX=" ✗ parse_mongo_url ${MONGO_URL}"

  parse_mongo_url ${MONGO_URL}

  check_eq "${TEST_USER}"     "${MONGO_USER}"     "${ERROR_PREFIX} "
  check_eq "${TEST_PASSWORD}" "${MONGO_PASSWORD}" "${ERROR_PREFIX} "
  check_eq "${TEST_HOST}"     "${MONGO_HOST}"     "${ERROR_PREFIX} "
  check_eq "${TEST_PORT}"     "${MONGO_PORT}"     "${ERROR_PREFIX} "
  check_eq "${TEST_DATABASE}" "${MONGO_DATABASE}" "${ERROR_PREFIX} "

  echo " ✓ parse_mongo_url ${MONGO_URL}"
}

source mongo-url.sh

check_mongo_url "" "" "" "" "27017" ""
check_mongo_url "mongo" "" "" "mongo" "27017" ""
check_mongo_url "mongodb://mongo" "" "" "mongo" "27017" ""
check_mongo_url "mongodb://mongo:27018/" "" "" "mongo" "27018" ""
check_mongo_url "mongodb://user@mongo" "user" "" "mongo" "27017" ""
check_mongo_url "mongodb://user:pa:@ss@mongo" "user" "pa:@ss" "mongo" "27017" ""
check_mongo_url "mongodb://user@mongo/db" "user" "" "mongo" "27017" "db"

echo "All tests passed"

usage.sh

#!/usr/bin/env bash

source mongo-url.sh

parse_mongo_url "mongodb://user:password@myhost.com/database

echo "Host: ${MONGO_HOST}"
echo "Port: ${MONGO_PORT}"
echo "User: ${MONGO_USER}"
echo "Password: ${MONGO_PASSWORD}"
echo "Database: ${MONGO_HOST}"