A bash script for kubectl port-foward, copy of https://github.com/johanhaleby/kubetail

kube-port-foward

#!/bin/bash

readonly PROGNAME=$(basename $0)

default_since="10s"
default_namespace="default"
default_line_buffered=""
default_colored_output="pod"

line_buffered="${default_line_buffered}"
colored_output="${default_colored_output}"

pod="${1}"
container=""
selector=""
since="${default_since}"

usage="${PROGNAME} [-h] [-c] [-n] [-t] [-l] [-s] -- kubectl port-foward

where:
-h, --help       	 Show this help text
-c, --container  	 The name of the container to tail in the pod (if multiple containers are defined in the pod). Default is none
-t, --context    	 The k8s context. ex. int1-context. Relies on ~/.kube/config for the contexts.
-l, --selector   	 Label selector. If used the pod name is ignored.
-n, --namespace  	 The Kubernetes namespace where the pods are located (defaults to "default")

examples:
${PROGNAME} my-pod-v1
${PROGNAME} my-pod-v1 -c my-container
${PROGNAME} my-pod-v1 -t int1-context -c my-container
${PROGNAME} -l service=my-service
${PROGNAME} --selector service=my-service --since 10m"

if [ $# -eq 0 ]; then
  echo "$usage"
  exit 1
fi

if [ "$#" -ne 0 ]; then
  while [ "$#" -gt 0 ]
  do
    case "$1" in
      -h|--help)
        echo "$usage"
        exit 0
        ;;
      -c|--container)
        container="$2"
        ;;
      -t|--context)
        context="$2"
        ;;
      -l|--selector)
        selector="--selector $2"
        pod=""
        ;;
      -n|--namespace)
        if [ -z "$2" ]; then
          namespace="${default_namespace}"
        else
          namespace="$2"
        fi
        ;;
      -b|--line-buffered)
        if [ "$2" = "true" ]; then
          line_buffered="| grep - --line-buffered"
        fi
        ;;
      -k|--colored-output)
        if [ -z "$2" ]; then
          colored_output="${default_colored_output}"
        else
          colored_output="$2"
        fi
        ;;
      --)
        break
        ;;
      -*)
        echo "Invalid option '$1'. Use --help to see the valid options" >&2
        exit 1
        ;;
        # an option argument, continue
        *)  ;;
      esac
      shift
    done
  fi

  # Join function that supports a multi-character seperator (copied from http://stackoverflow.com/a/23673883/398441)
  function join() {
    # $1 is return variable name
    # $2 is sep
    # $3... are the elements to join
    local retname=$1 sep=$2 ret=$3
    shift 3 || shift $(($#))
    printf -v "$retname" "%s" "$ret${@/#/$sep}"
  }

  # Get all pods matching the input and put them in an array. If no input then all pods are matched.
  matching_pods=(`kubectl get pods --context=${context} --no-headers ${selector} --namespace=${namespace} | grep "${pod}" | sed 's/ .*//'`)
  matching_pods_size=${#matching_pods[@]}

  if [ ${matching_pods_size} -eq 0 ]; then
    echo "No pods exists that matches ${pod}"
    exit 1
  else
    echo "Pod found ${#matching_pods[@]} ..."
  fi

  color_end=$(tput sgr0)

  # Wrap all pod names in the "kubectl logs <name> -f" command
  pod_commands=()
  for i in ${!matching_pods[@]};
  do
    pod=${matching_pods[$i]}

    # pod_commands+=("kubectl --context=${context} logs ${pod} ${container} -f --since=${since} --namespace=${namespace} | while read line; do echo \"$colored_line\"; done");
    pod_commands+=("kubectl --context=${context} port-forward ${pod} ${container} --namespace=${namespace} 8080:80");
  done

  # Join all log commands into one string seperated by " & "
  join command_to_tail " & " "${pod_commands[@]}"

  # Aggreate all logs and print to stdout
  CMD="cat <( eval "${command_to_tail}" ) $line_buffered"
  eval "$CMD"