push-to-dokku/services.go

package main

import (
	"bytes"
	"fmt"
	"github.com/bitfield/script"
	"log"
	"os"
	"text/template"
)

type Services struct {
	cfg config
}

func NewServices(cfg config) *Services {
	return &Services{cfg: cfg}
}

func (s *Services) AddPrivateKey() error {
	log.Println("Adding private key")

	if err := runCmd(`mkdir -p $HOME/.ssh`); err != nil {
		return err
	}

	if err := writeFile(`${HOME}/.ssh/id_rsa`, s.cfg.PrivateKey, 0400); err != nil {
		return err
	}

	if err := runCmd(`chmod 700 $HOME/.ssh`); err != nil {
		return err
	}

	return nil
}

func (s *Services) ConfigureSSH() error {
	log.Println("Configuring SSH")

	var bfr bytes.Buffer
	if err := sshConfigTemplate.Execute(&bfr, struct {
		Cfg  config
		Home string
	}{
		Cfg:  s.cfg,
		Home: os.Getenv("HOME"),
	}); err != nil {
		return err
	}

	if err := writeFile(`${HOME}/.ssh/config`, bfr.String(), 0400); err != nil {
		return err
	}

	return nil
}

func (s *Services) PushRepository() error {
	sshUrl := fmt.Sprintf(`dokku@%v`, s.cfg.HostName)
	remoteUrl := fmt.Sprintf(`ssh://%v:22/%v`, sshUrl, s.cfg.AppName)

	log.Println("Testing Dokku SSH connection")
	if err := runCmd(fmt.Sprintf(`ssh %v version`, sshUrl)); err != nil {
		return err
	}

	log.Println("SSH connection good. Pushing repository")
	if err := runCmd(fmt.Sprintf(`git remote add dokku '%v'`, remoteUrl)); err != nil {
		return err
	}

	if err := runCmd(`git push dokku main`); err != nil {
		return err
	}

	return nil
}

func runCmd(cmd string) error {
	fullCmd := os.ExpandEnv(cmd)
	log.Printf(" .. [exec] %v", fullCmd)
	return script.Exec(fullCmd).Error()
}

func writeFile(path string, content string, mode os.FileMode) error {
	fullPath := os.ExpandEnv(path)
	log.Printf(" .. [file] %v", fullPath)

	return os.WriteFile(fullPath, []byte(content), mode)
}

var (
	sshConfigTemplate = template.Must(template.New("ssh-config").Parse(`
Host *
  StrictHostKeyChecking no

Host {{.Cfg.Host}}
  HostName {{.Cfg.Host}}
  User dokku
  IdentityFile {{.Home}}/.ssh/id_rsa
`))
)