A Script to Query a consul cluster then output a summary of services instances and a CSV files containing services names and service instance IDs

consul_instance_count.sh

#! /bin/bash
################################
# Requirements: curl, jq
################################

## avoid the last trailling forward slash /

usage="$(basename "$0") [-a consul_http_address] [-t acl_token] [-e IS_ENTERPRISE] [-l LIST_INSTACES]
where 
    -a Consul HTTP(s) Address.
    -t Consul ACL token with permissions to read nodes and services across DCs(if applicable).
    -e If the target is an enterprise Consul, look over namespaces and count services across namespaces.
    -l If provided, list all service instances found into a csv file.
"

while getopts :a:t:e:l:h: flag
do
  case "$flag" in
    a) ADDRESS=$OPTARG;;
    t) ACL_TOKEN=$OPTARG;;
    e) IS_ENTERPRISE=$OPTARG;;
    l) LIST_INSTANCES=$OPTARG;;
    h) echo "$usage"
       exit
       ;;
    :) printf "missing argument for -%s\n" "$OPTARG" >&2
       echo "$usage" >&2
       exit 1
       ;;
  esac
done

IS_ENTERPRISE=${IS_ENTERPRISE:-false}
LIST_INSTANCES=${LIST_INSTANCES:-false}

echo "Is Enterprise: $IS_ENTERPRISE"
echo "List instances: $LIST_INSTANCES"

if $LIST_INSTANCES;then
 SERVICES_LIST_FILE_TABLE="services_list_tabled_$(date +"%Y.%m.%d").txt"
 SERVICES_LIST_FILE_CSV="services_list_tabled_$(date +"%Y.%m.%d").csv"        
 echo "Service, ID" >> $SERVICES_LIST_FILE_CSV
fi

if [ ! "$ADDRESS" ] ; then
  echo "Argument -a must be provided"
  echo "$usage" >&2; exit 1
fi

if [ "$ACL_TOKEN" = "" ]
then
    HEADER=""
else 
    HEADER="X-Consul-Token: $ACL_TOKEN"
fi

total_service_instances=0
total_nodes=0
DCS=$(curl -ks \
    -H "$HEADER" \
    $ADDRESS/v1/catalog/datacenters | jq -r '[ .[] ]| join (" ")' )

for DC in $DCS; do
    echo "--------------------------------"
    echo "Countin Services in dc $DC"
    
    NODES=$(curl -ks \
    -H "$HEADER" \
    $ADDRESS/v1/catalog/nodes?dc=$DC | jq -r '[ .[].Node ]| join (" ")' )


    for node in $NODES; do
        if [[ $node =~ .*consul-server.* ]]; then
            continue
        fi
        total_nodes=$(($total_nodes+1))
        if $IS_ENTERPRISE;then
            query="ns=*&dc=$DC"
        else 
            query="dc=$DC"
        fi
        echo "Getting services from $node"
        if $LIST_INSTANCES;then
            # echo "Getting services from $node" >> $SERVICES_LIST_FILE_TABLE
            curl -s "$CONSUL_HTTP_ADDR/v1/catalog/node-services/$node?$query" | jq -r '.Services[] | select(.Service | contains("consul") | not) | "\(.Service)\t\(.ID)"' | column -t >> $SERVICES_LIST_FILE_TABLE
            ########
            curl -s "$CONSUL_HTTP_ADDR/v1/catalog/node-services/$node?$query" | jq -r '.Services[]| select(.Service | contains("consul") | not)| [.Service, .ID]| @csv' >> $SERVICES_LIST_FILE_CSV
            ########
        fi
            service_instances=$(curl -ks \
            -H "$HEADER" \
            $ADDRESS/v1/catalog/node-services/$node?$query | jq  'try (.Services | map(select(.ID | contains("consul") | not) ) ) catch 0 | length')
        
        echo " - found $service_instances"
        total_service_instances=$(($total_service_instances+$service_instances))
    done
done


echo "--------------------------------"
echo "Total service instances found: $total_service_instances"
echo "Total number of nodes: $total_nodes"
echo ""