Containers and Service auto registration through Consul for openVZ CT (via ovz action scripts)

vps.mount

#!/bin/bash 

set -eo pipefail

CONSUL_EP="IP:PORT"

main() {

  # Exit when required files are not present
  [[ -f /etc/vz/vz.conf ]] || exit 1
  [[ -f $VE_CONFFILE ]] || exit 1

  # Source the CT conf file
  . $VE_CONFFILE

  # Register CT in consul (Exept for consul server itself : ns1)
  [[ "${HOSTNAME}" == "ns1" ]] \
  || curl --noproxy "*" -sS ${CONSUL_EP}/v1/catalog/register \
     -d '{
          "Node": "'${HOSTNAME}'",
          "Address": "'${IP_ADDRESS}'",
          "Check": {
            "Node": "'${HOSTNAME}'",
            "Name": "'${HOSTNAME}' status",
            "Status": "passing"
          }
        }' \
     > /dev/null

  # Services should be stored in "description" field with the following format : 
  #   vzctl set ${VEID} --description '{
  #     "services": [
  #        {
  #          "name": "graphite",
  #          "port": "2300",
  #          "tags": [
  #            "tag1"
  #          ]
  #        },
  #        {
  #          "name": "service1"
  #        },
  #        {
  #          "name": "service2"
  #        }
  #      ],
  #     "tags": [],
  #     "description": ""
  #   }'

  # Get list of services for this CT
  SERVICES=$(/usr/sbin/vzlist ${VEID} -o description -H | jq -cr ".services[]" 2>/dev/null)

  # Register Services in consul
  for SERVICE in $SERVICES; do

    echo "Adding ${SERVICE} to service discovery"

    # Detect description format

    # Must be one of :
    #   - {"services": [{"name":"graphite","port":"2300","tags":["tag1"]}] }
    #   - {"services": ["service:port#tag","service","service:port","service#tag"] }

    local DETAILED_FORMAT=$(echo "${SERVICE}" | jq . 2>&1>/dev/null && echo "true" || echo "false")

    [[ "${DETAILED_FORMAT}" == "true" ]] && {

      local NAME="$(echo "${SERVICE}" | jq -r '.name // 0')"
      local PORT="$(echo "${SERVICE}" | jq -r '.port // 0')"
      local TAGS="$(echo "${SERVICE}" | jq -r '.tags // []')"

      local PAYLOAD='{
             "Service": "'"${NAME}"'",
             "Tags": '"${TAGS}"',
             "Port": '"${PORT}"'
           }'

    } || {

      local NAME_PORT="${SERVICE%%#*}"
      local NAME="${NAME_PORT%%:*}"
      local PORT="${NAME_PORT##*:}"
      local TAG="${SERVICE##*#}"

      [[ "${PORT}" == "${NAME_PORT}" ]] && PORT=0
      [[ "${TAG}" == "${NAME_PORT}" ]] && TAG=""

      local PAYLOAD='{
             "Service": "'"${NAME}"'",
             "Port": '"${PORT}"',
             "Tags": ["'"${TAG}"'"]
           }'

    }

    curl --noproxy "*" -sS ${CONSUL_EP}/v1/catalog/register -d '{
      "Node": "'${HOSTNAME}'",
      "Address": "'${IP_ADDRESS}'",
      "Service": '"${PAYLOAD}"'
    }' \
    > /dev/null

  done

}

main &
disown
exit 0