kubectl-diagrams

#!/bin/bash

# kubectl diagrams: A kubectl plugin to generate a diagram of Kubernetes resources
# using kube-diagrams from the output of 'kubectl get <resources> -o yaml'

# Version
VERSION="0.1.0"

# Check if kube-diagrams is installed
if ! command -v kube-diagrams &>/dev/null; then
  echo "Error: kube-diagrams is not installed. Please install it first."
  exit 1
fi

# Check if kubectl is installed
if ! command -v kubectl &>/dev/null; then
  echo "Error: kubectl is not installed. Please install it first."
  exit 1
fi

# Display help message
show_help() {
  echo "Usage: kubectl diagrams [OPTIONS] <resource1,resource2,...>"
  echo ""
  echo "A kubectl plugin to generate diagrams of Kubernetes resources using kube-diagrams."
  echo ""
  echo "Options:"
  echo "  -n, --namespace <namespace>  Specify the namespace to query resources from"
  echo "  -o, --output <file>          Specify the output file for the diagram"
  echo "  -f, --format <format>        Specify the output format (e.g., png, svg)"
  echo "  --embed-all-icons            Embed all icons into svg or dot_json output diagrams"
  echo "  -c, --config <file>          Specify the custom kube-diagrams configuration file"
  echo "      --without-namespace      Exclude namespace from the diagram"
  echo "      --version                Display the version number"
  echo "      --help                   Display this help message"
  echo ""
  echo "Examples:"
  echo "  kubectl diagrams pod,service -n my-namespace -o diagram.png"
  echo "  kubectl diagrams deployment --without-namespace -f svg"
  echo "  kubectl diagrams --version"
  exit 0
}

# Initialize variables
KUBE_DIAGRAMS_ARGS=("-") # Default to stdin indicator
KUBECTL_ARGS=()

# Parse arguments
while [[ $# -gt 0 ]]; do
  case "$1" in
  --version)
    echo "kubectl diagrams version $VERSION"
    exit
    ;;
  --help)
    show_help
    ;;
  -n | --namespace)
    if [[ -n "$2" ]]; then
      KUBECTL_ARGS+=("-n" "$2")
      shift 2
    else
      echo "Error: --namespace requires a value"
      exit 64
    fi
    ;;
  -o | --output | -f | --format | -c | --config | --without-namespace)
    KUBE_DIAGRAMS_ARGS+=("$1")
    if [[ "$1" == "-o" || "$1" == "--output" || "$1" == "-f" || "$1" == "--format" || "$1" == "-c" || "$1" == "--config" ]]; then
      if [[ -n "$2" ]]; then
        KUBE_DIAGRAMS_ARGS+=("$2")
        shift 2
      else
        echo "Error: $1 requires a value"
        exit 64
      fi
    else
      shift
    fi
    ;;
  --embed-all-icons)
    KUBE_DIAGRAMS_ARGS+=("$1")
    shift
    ;;
  *)
    KUBECTL_ARGS+=("$1")
    shift
    ;;
  esac
done

# Check if any resources were specified
if [[ ${#KUBECTL_ARGS[@]} -eq 0 ]]; then
  echo "Error: At least one resource kind must be specified (e.g., pod, service, deployment)"
  exit 64
fi

# Add default output format for kubectl
KUBECTL_ARGS+=("-o" "yaml")

# Execute kubectl and pipe to kube-diagrams with arguments
kubectl get "${KUBECTL_ARGS[@]}" | kube-diagrams "${KUBE_DIAGRAMS_ARGS[@]}"
EXIT_CODE=$?

if [[ $EXIT_CODE -eq 0 ]]; then
  echo "Diagram generated successfully"
else
  echo "Error: Failed to generate diagram"
  exit 1
fi