feat(runner): allow user to include terraform & terragrunt binaries in runner image

cmd/runner/start.go

@@ -20,5 +20,6 @@ func buildRunnerStartCmd(app *burrito.App) *cobra.Command {
 	}
 
 	cmd.Flags().StringVar(&app.Config.Runner.SSHKnownHostsConfigMapName, "ssh-known-hosts-cm-name", "burrito-ssh-known-hosts", "configmap name to get known hosts file from")
+	cmd.Flags().StringVar(&app.Config.Runner.RunnerBinaryPath, "runner-binary-path", "/runner/bin", "binary path where the runner can expect to find terraform or terragrunt binaries")
 	return cmd
 }

go.sum

@@ -85,6 +85,7 @@ github.com/cyphar/filepath-securejoin v0.2.4/go.mod h1:aPGpWjXOXUn2NCNjFvBE6aRxG
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/dgrijalva/jwt-go v3.2.0+incompatible/go.mod h1:E3ru+11k8xSBh+hMPgOLZmtrrCbhqsmaPHjLKYnJCaQ=
 github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f h1:lO4WD4F/rVNCu3HqELle0jiPLLBs70cWOduZpkS1E78=
 github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f/go.mod h1:cuUVRXasLTGF7a8hSLbxyZXjz+1KgoB3wDUb6vlszIc=
 github.com/elazarl/goproxy v0.0.0-20230808193330-2592e75ae04a h1:mATvB/9r/3gvcejNsXKSkQ6lcIaNec2nyfOdlTBR2lU=
@@ -280,6 +281,8 @@ github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
+github.com/labstack/echo v3.3.10+incompatible h1:pGRcYk231ExFAyoAjAfD85kQzRJCRI8bbnE7CX5OEgg=
+github.com/labstack/echo v3.3.10+incompatible/go.mod h1:0INS7j/VjnFxD4E2wkz67b8cVwCLbBmJyDaka6Cmk1s=
 github.com/labstack/echo/v4 v4.11.2 h1:T+cTLQxWCDfqDEoydYm5kCobjmHwOwcv4OJAPHilmdE=
 github.com/labstack/echo/v4 v4.11.2/go.mod h1:UcGuQ8V6ZNRmSweBIJkPvGfwCMIlFmiqrPqiEBfPYws=
 github.com/labstack/echo/v4 v4.11.4 h1:vDZmA+qNeh1pd/cCkEicDMrjtrnMGQ1QFI9gWN1zGq8=

internal/burrito/config/config.go

@@ -79,6 +79,7 @@ type RunnerConfig struct {
 	Layer                      Layer            `mapstructure:"layer"`
 	Repository                 RepositoryConfig `mapstructure:"repository"`
 	SSHKnownHostsConfigMapName string           `mapstructure:"sshKnownHostsConfigMapName"`
+	RunnerBinaryPath           string           `mapstructure:"runnerBinaryPath"`
 }
 
 type Layer struct {

internal/runner/runner.go

@@ -146,7 +146,7 @@ func newK8SClient() (client.Client, error) {
 
 func (r *Runner) install() error {
 	terraformVersion := configv1alpha1.GetTerraformVersion(r.repository, r.layer)
-	terraformExec := terraform.NewTerraform(terraformVersion, PlanArtifact)
+	terraformExec := terraform.NewTerraform(terraformVersion, PlanArtifact, r.config.Runner.RunnerBinaryPath)
 	terraformRuntime := "terraform"
 	if configv1alpha1.GetTerragruntEnabled(r.repository, r.layer) {
 		terraformRuntime = "terragrunt"
@@ -157,7 +157,7 @@ func (r *Runner) install() error {
 		r.exec = terraformExec
 	case "terragrunt":
 		log.Infof("using terragrunt")
-		r.exec = terragrunt.NewTerragrunt(terraformExec, configv1alpha1.GetTerragruntVersion(r.repository, r.layer), PlanArtifact)
+		r.exec = terragrunt.NewTerragrunt(terraformExec, configv1alpha1.GetTerragruntVersion(r.repository, r.layer), PlanArtifact, r.config.Runner.RunnerBinaryPath)
 	}
 	err := r.exec.Install()
 	if err != nil {

internal/runner/terraform/terraform.go

@@ -8,8 +8,11 @@ import (
 	"os"
 
 	"github.com/hashicorp/go-version"
+	install "github.com/hashicorp/hc-install"
+	"github.com/hashicorp/hc-install/fs"
 	"github.com/hashicorp/hc-install/product"
 	"github.com/hashicorp/hc-install/releases"
+	"github.com/hashicorp/hc-install/src"
 	"github.com/hashicorp/terraform-exec/tfexec"
 )
 
@@ -18,12 +21,14 @@ type Terraform struct {
 	version          string
 	ExecPath         string
 	planArtifactPath string
+	runnerBinaryPath string
 }
 
-func NewTerraform(version, planArtifactPath string) *Terraform {
+func NewTerraform(version, planArtifactPath string, runnerBinaryPath string) *Terraform {
 	return &Terraform{
 		version:          version,
 		planArtifactPath: planArtifactPath,
+		runnerBinaryPath: runnerBinaryPath,
 	}
 }
 
@@ -32,11 +37,23 @@ func (t *Terraform) Install() error {
 	if err != nil {
 		return err
 	}
-	installer := &releases.ExactVersion{
+	i := install.NewInstaller()
+	version := version.Must(terraformVersion, nil)
+	fs := fs.ExactVersion{
 		Product: product.Terraform,
-		Version: version.Must(terraformVersion, nil),
+		Version: version,
+		ExtraPaths: []string{
+			t.runnerBinaryPath,
+		},
 	}
-	execPath, err := installer.Install(context.Background())
+	releases := releases.ExactVersion{
+		Product: product.Terraform,
+		Version: version,
+	}
+	execPath, err := i.Ensure(context.Background(), []src.Source{
+		&fs,
+		&releases,
+	})
 	if err != nil {
 		return err
 	}

internal/runner/terragrunt/terragrunt.go

@@ -1,6 +1,7 @@
 package terragrunt
 
 import (
+	"crypto/sha256"
 	"errors"
 	"fmt"
 	"io"
@@ -9,12 +10,10 @@ import (
 	"os/exec"
 	"path/filepath"
 	"runtime"
+	"strings"
 
 	"github.com/padok-team/burrito/internal/runner/terraform"
-)
-
-const (
-	BinWorkDir = "/runner/bin"
+	log "github.com/sirupsen/logrus"
 )
 
 type Terragrunt struct {
@@ -23,13 +22,15 @@ type Terragrunt struct {
 	version          string
 	workingDir       string
 	terraform        *terraform.Terraform
+	runnerBinaryPath string
 }
 
-func NewTerragrunt(terraformExec *terraform.Terraform, terragruntVersion, planArtifactPath string) *Terragrunt {
+func NewTerragrunt(terraformExec *terraform.Terraform, terragruntVersion, planArtifactPath string, runnerBinaryPath string) *Terragrunt {
 	return &Terragrunt{
 		version:          terragruntVersion,
 		terraform:        terraformExec,
 		planArtifactPath: planArtifactPath,
+		runnerBinaryPath: runnerBinaryPath,
 	}
 }
 
@@ -43,7 +44,8 @@ func (t *Terragrunt) Install() error {
 	if err != nil {
 		return err
 	}
-	path, err := downloadTerragrunt(t.version)
+
+	path, err := ensureTerragrunt(t.version, t.runnerBinaryPath)
 	if err != nil {
 		return err
 	}
@@ -115,7 +117,94 @@ func (t *Terragrunt) Show(mode string) ([]byte, error) {
 	return output, nil
 }
 
-func downloadTerragrunt(version string) (string, error) {
+func ensureTerragrunt(version string, runnerBinaryPath string) (string, error) {
+	files, err := os.ReadDir(runnerBinaryPath)
+	if err != nil {
+		return "", err
+	}
+
+	trustedHash, err := getTerragruntSHA256(version)
+	if err != nil {
+		return "", err
+	}
+
+	for _, file := range files {
+		if !file.IsDir() {
+			runnerBinaryFullPath := filepath.Join(runnerBinaryPath, file.Name())
+			hash, err := calculateFileSHA256(runnerBinaryFullPath)
+			if err != nil {
+				return "", err
+			}
+
+			if hash == trustedHash {
+				err = os.Chmod(runnerBinaryFullPath, 0755)
+				if err != nil {
+					return "", err
+				}
+				log.Infof("Terragrunt binary found at %s, using it", runnerBinaryFullPath)
+				return filepath.Abs(runnerBinaryFullPath)
+			}
+
+		}
+	}
+
+	log.Infof("Terragrunt binary not found, downloading it... (Consider packaging binaries within your runner image to mitigate eventual network expenses)")
+	path, err := downloadTerragrunt(version, runnerBinaryPath)
+	log.Infof("Downloaded terragrunt binaries to %s", path)
+	if err != nil {
+		return "", err
+	}
+
+	return path, nil
+}
+
+func calculateFileSHA256(filename string) (string, error) {
+	file, err := os.Open(filename)
+	if err != nil {
+		return "", err
+	}
+	defer file.Close()
+
+	hash := sha256.New()
+
+	if _, err := io.Copy(hash, file); err != nil {
+		return "", err
+	}
+
+	return fmt.Sprintf("%x", hash.Sum(nil)), nil
+}
+
+func getTerragruntSHA256(version string) (string, error) {
+	cpuArch := runtime.GOARCH
+	response, err := http.Get(fmt.Sprintf("https://github.com/gruntwork-io/terragrunt/releases/download/v%s/SHA256SUMS", version))
+	if err != nil {
+		return "", err
+	}
+	defer response.Body.Close()
+
+	body, err := io.ReadAll(response.Body)
+	if err != nil {
+		return "", err
+	}
+
+	lines := strings.Split(string(body), "\n")
+	for _, line := range lines {
+		parts := strings.Fields(line)
+		if len(parts) != 2 {
+			continue
+		}
+		sha := parts[0]
+		filename := parts[1]
+
+		if strings.Contains(filename, fmt.Sprintf("linux_%s", cpuArch)) {
+			return sha, nil
+		}
+	}
+
+	return "", errors.New("could not find a hash for this architecture in SHA256SUMS file")
+}
+
+func downloadTerragrunt(version string, runnerBinaryPath string) (string, error) {
 	cpuArch := runtime.GOARCH
 
 	url := fmt.Sprintf("https://github.com/gruntwork-io/terragrunt/releases/download/v%s/terragrunt_linux_%s", version, cpuArch)
@@ -126,7 +215,7 @@ func downloadTerragrunt(version string) (string, error) {
 	}
 	defer response.Body.Close()
 
-	filename := fmt.Sprintf("%s/terragrunt_%s", BinWorkDir, cpuArch)
+	filename := fmt.Sprintf("%s/terragrunt_%s", runnerBinaryPath, cpuArch)
 	file, err := os.Create(filename)
 	if err != nil {
 		return "", err