Visual graph for Drone pipelines

main.go

package main

import (
	"fmt"
	"log"
	"os"

	"github.com/drone/drone-yaml/yaml"
	"github.com/goccy/go-graphviz"
	"github.com/goccy/go-graphviz/cgraph"
	"github.com/namsral/flag"
)

var ()

func main() {
	filename := flag.String("filename", ".drone.yml", "path for the drone file to analyze")

	flag.Parse()

	f, err := os.Open(*filename)
	if err != nil {
		log.Fatal(err)
	}

	manifest, err := yaml.Parse(f)
	if err != nil {
		log.Fatal(err)
	}

	g := graphviz.New()
	graph, err := g.Graph()
	if err != nil {
		log.Fatal(err)
	}

	for _, ressource := range manifest.Resources {
		if ressource.GetKind() == yaml.KindPipeline {
			m := make(map[string]*cgraph.Node)
			pipeline := ressource.(*yaml.Pipeline)

			first := true
			for _, step := range pipeline.Steps {
				n, err := graph.CreateNode(step.Name)
				if err != nil {
					log.Fatal(err)
				}

				if first {
					_ = n.SetLabel(fmt.Sprintf("%s %s", pipeline.Name, step.Name))
					first = false
				}

				m[step.Name] = n
				for _, sdep := range step.DependsOn {
					pnode, ok := m[sdep]
					if !ok {
						log.Fatal("cant find step", sdep)
					}
					_, err := graph.CreateEdge(n.Name(), pnode, n)
					if err != nil {
						log.Fatal(err)
					}
				}
			}
		}

	}

	if err := g.RenderFilename(graph, graphviz.PNG, "graph.png"); err != nil {
		log.Fatal(err)
	}
}