hcl-simple-example-2.go

package main

import (
	"fmt"
	"os"

	"github.com/hashicorp/hcl/v2"
	"github.com/hashicorp/hcl/v2/gohcl"
	"github.com/hashicorp/hcl/v2/hclsimple"
)

var (
	exampleHCL = `
		task "first_task" {
			step "mkdir" "build_dir" {
				path = "./build/"
			}
			step "exec" "list_build_dir" {
				command = "ls ./build/"
			}
		}
	`
)

func main() {
	config := &Config{}
	err := hclsimple.Decode("example.hcl", []byte(exampleHCL), nil, config)
	if err != nil {
		fmt.Println(err)
		os.Exit(1)
	}
	for _, task := range config.Tasks {
		fmt.Printf("Task: %s\n", task.Name)
		for _, step := range task.Steps {
			fmt.Printf("    Step: %s %s\n", step.Type, step.Name)

			var runner Runner

			switch step.Type {
			case "mkdir":
				runner = &MkdirStep{}
			case "exec":
				runner = &ExecStep{}
			default:
				fmt.Printf("Unknown step type %q\n", step.Type)
				os.Exit(1)
			}

			diags := gohcl.DecodeBody(step.Remain, nil, runner)
			if diags.HasErrors() {
				fmt.Println(diags)
				os.Exit(1)
			}
			err = runner.Run()
			if err != nil {
				fmt.Println(err)
				os.Exit(1)
			}
		}
	}
}

type Config struct {
	Tasks []*Task `hcl:"task,block"`
}
type Task struct {
	Name  string  `hcl:"name,label"`
	Steps []*Step `hcl:"step,block"`
}

type Step struct {
	Type   string   `hcl:"type,label"`
	Name   string   `hcl:"name,label"`
	Remain hcl.Body `hcl:",remain"`
}

type ExecStep struct {
	Command string `hcl:"command"`
}

func (s *ExecStep) Run() error {
	return nil
}

type MkdirStep struct {
	Path string `hcl:"path"`
}

func (s *MkdirStep) Run() error {
	return nil
}

type Runner interface {
	Run() error
}