Shell script to manage rqlite process

rqlite.sh

#!/bin/bash

if [ "${BASH_VERSINFO:-0}" -lt 4 ]
then
  echo "bash version: ${BASH_VERSION}"
  echo "Current bash version doesn't support associative arrays, require bash version >=4"
  exit 1
fi

hostname=$(hostname)
command="$1"
service_name="rqlited"
auth_client_json_file="$HOME/rqlite/auth/auth-clients.json"
data_path="$HOME/rqlite/data"
http_cert="$HOME/rqlite/cert/rqlite.pem"
http_key="$HOME/rqlite/cert/rqlite.key"
node_cert="$HOME/rqlite/cert/rqlite.pem"
node_key="$HOME/rqlite/cert/rqlite.key"
user_name="rqlite"
# URL encoded
pwd="<replace with url encoded password>"

# rqlite nodes in the cluster.
# Should replace server1, server2, server3 with the actual server hostname.
declare -a cluster=("https://$user_name:$pwd@server1:4001"
"https://$user_name:$pwd@server2:4001"
"https://$user_name:$pwd@server3:4001")

join_urls=""

# Build join urls
build_join_urls() {
    local self_node_url="https://$user_name:$pwd@$hostname:4001"
    # Remove self node url from cluster node urls.
    local cluster_exclude_self_node=( "${cluster[@]/$self_node_url}" )
    local temp=$(printf ",%s" "${cluster_exclude_self_node[@]}")
    join_urls=${temp:1}
}

# Start rqlite if it's not running.
start() {
  if [ -z "$1" ]
  then
    echo "process name is required."
    return
  fi
  without_join_urls=$2

  local process_name=$1
  local running_process_count
  running_process_count=$(ps -ef | grep "$process_name" | grep -v "grep" | wc -l)
  if [ "$running_process_count" -ne 0 ]
  then
    echo "$process_name is running, skip it."
    return
  fi

  if [ -z "$without_join_urls" ]
  then
    build_join_urls
    echo "Start rqlite with join urls: $join_urls"
    nohup ./rqlited -node-id "$hostname" -http-addr "$hostname:4001" -raft-addr "$hostname:4002" -auth "$auth_client_json_file" -http-cert "$http_cert" -http-key "$http_key" -node-encrypt -node-cert "$node_cert" -node-key "$node_key" -node-no-verify -join "$join_urls" "$data_path" &> rqlite.log &
  else
    # $without_join_urls value is not empty
    # Start rqlite without join urls.
    echo "Start rqlite without join urls, rqlite with run in standalone mode, it will not join to any cluster."
    nohup ./rqlited -node-id "$hostname" -http-addr "$hostname:4001" -raft-addr "$hostname:4002" -auth "$auth_client_json_file" -http-cert "$http_cert" -http-key "$http_key" -node-encrypt -node-cert "$node_cert" -node-key "$node_key" -node-no-verify "$data_path" &> rqlite.log &
  fi

  local pid=$(pgrep -f "$process_name")
  echo "$process_name started, pid: $pid"
}

# Stop rqlite.
stop() {
  if [ -z "$1" ]
  then
    echo "process name is required."
    return
  fi

  local process_name=$1
  local running_process_count
  running_process_count=$(ps -ef | grep "$process_name" | grep -v "grep" | wc -l)
  if [ "$running_process_count" -eq 0 ]
  then
    echo "$process_name is not running, skip it."
    return
  fi

  local pid=$(pgrep -f "$process_name")
  if [ -z "$pid" ]
  then
    echo "$process_name is not running."
    return
  else
    echo "Prepare to stop pid: $pid, process name:"
    ps -p "$pid" -o command h
    kill -9 "$pid"
    echo "Waiting pid: $pid to exit..."
    tail --pid="$pid" -f /dev/null
    echo "pid: $pid has been stopped successfully."
  fi
}

restart() {
  stop "$service_name"
  start "$service_name"
}

start_standalone() {
    start "$service_name" 1
}

case "$command" in
start)
  start "$service_name"
  ;;
start_standalone)
  start_standalone
  ;;  
restart)
  restart "$service_name"
  ;;
stop)
  stop "$service_name"
  ;;
*)
  cat << EOF

./cnesb.sh {COMMAND}
Manage rqlite service.

Usage:
  start                Start rqlite service.
  stop                 Stop rqlite service.
  restart              Restart rqlite service.
  start_standalone     Start with standalone mode, it will not join to any cluster.

EOF
  exit 1
  ;;
esac