Script to fetch linkerd-proxy logs and metrics for a set of Kubernetes pods with a common label value

dev-stats.sh

#!/usr/bin/env bash

print_summary() {
  local name="${0##*/}"
  printf "Collect proxy-logs and diagnostics\n\nUsage:\n %2s ${name} --namespace name [--selector \"key=value\"] [--o /output/path]\n\n"
  printf "Examples:\n"
  printf "%2s#Collect logs and diagnostics for all pods in 'test'\n%2s${name} --namespace test\n\n"
  printf "%2s#Collect logs and diagnostics for pods with 'app=test' label\n%2s${name} --namespace test --selector \"app=test\"\n\n"
  printf "%2s#Output files in a different path\n%2s${name} --namespace 'test' --o /path/to/files\n\n"
  printf "NOTE:\n%2s*%1sFiles will be named based on the pod and will include either a '.dg' or a '.log' extension\n%2s*%1sSelector supports only one k=v pair\n\n"
}

mk_opts() {
  export namespace=''
  export selector=''
  export path=''

  if [ $# -eq 0 ]; then
    print_summary "$0"
    exit 0
  fi

  while [ $# -ne 0 ]; do
    case $1 in
      -h|--help)
        print_summary "$0"
        exit 0
        ;;
      -n|--namespace)
        namespace="$2"
        if [ -z "$namespace" ]; then
          echo "Error: argument for --namespace not specified" >&2
          exit 64
        fi
        shift
        shift
        ;;
      -s|--selector)
        selector="$2"
        shift
        shift
        ;;
      -o|--output)
        path="$2"
        shift
        shift
        ;;
      *)
    esac
  done

  if [ -z "$namespace" ]; then
    echo 'Error: namespace argument required' >&2
    exit 64
  fi

  if [ -z "$path" ]; then
    path="$(dirname "$0")"
  fi
}

_kubectl_get_pods() {
  local ns=$1
  local select=$2
  echo $(kubectl get po -n $ns --selector $select -o jsonpath='{range .items[*]}{.metadata.name}{"\n"}{end}')
}

run() {
  d="$1"
  ns="$2"
  select="$3"
  echo "Fetching logs and dg for pods with label '$select' in namespace '$ns'"
  local count=0
  for name in $(_kubectl_get_pods "$ns" "$select"); do
    echo "Extracting logs for $name..."
    $(kubectl logs -n "$ns" "$name" linkerd-proxy > "$path/$name-$d.log")
    echo "Extracting diagnostics for $name..."
    $(linkerd dg proxy-metrics -n "$ns" "po/$name" > "$path/$name-$d.dg")
    ((count+=2))
  done
  echo "Saved $count files in $path"
  echo "Done"

}

mk_opts "$@"
date="$(date +'%H:%M:%S')"
run "$date" "$namespace" "$selector"