init

internal/build/builder.go

@@ -0,0 +1,72 @@
+package build
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+
+	"code.vulpine.solutions/sam/vlp/internal/packages"
+)
+
+type Builder struct {
+	Name         string
+	Version      string
+	Dependencies []packages.Dependency
+
+	SourceFetcher Fetcher
+	Commands      []BuildCommand
+	Binaries      []string
+
+	TempDir string
+}
+
+type BuildCommand struct {
+	Command string
+	Args    []string
+}
+
+func New(name, version string) (*Builder, error) {
+	b := &Builder{
+		Name:    name,
+		Version: version,
+	}
+
+	tmp, err := tmpDir(name, version)
+	if err != nil {
+		return nil, err
+	}
+
+	b.TempDir = tmp
+	return b, nil
+}
+
+func (b *Builder) Build() error {
+	for i, cmd := range b.Commands {
+		exitCode, out := execCommand(cmd.Command, cmd.Args...)
+		if exitCode != 0 {
+			return fmt.Errorf("command %d returned exit code %d: %v", i, exitCode, string(out))
+		}
+	}
+	return nil
+}
+
+func tmpDir(name, version string) (string, error) {
+	tmp, err := os.MkdirTemp(os.TempDir(), "vlp-build-"+name+"-"+version+"_")
+	if err != nil {
+		return "", fmt.Errorf("creating temp dir: %w", err)
+	}
+	return tmp, nil
+}
+
+func execCommand(bin string, args ...string) (int, []byte) {
+	err := exec.Command(bin, args...).Run()
+	if err != nil {
+		eErr, ok := err.(*exec.ExitError)
+		if ok {
+			return eErr.ExitCode(), eErr.Stderr
+		}
+
+		return 1, nil
+	}
+	return 0, nil
+}

internal/build/fetcher.go

@@ -0,0 +1,51 @@
+package build
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+)
+
+type Fetcher interface {
+	Fetch(tempDir string) error
+}
+
+type BlankFetcher struct{}
+
+func (BlankFetcher) Fetch(tempDir string) error {
+	return fmt.Errorf("no sources were configured")
+}
+
+var _ Fetcher = (*GitFetcher)(nil)
+
+type GitFetcher struct {
+	Repository, Ref string
+}
+
+func (g GitFetcher) Fetch(tempDir string) error {
+
+	repoDir := filepath.Join(tempDir, "repo")
+	exitCode, out := execCommand("git", "clone", "--depth=1", g.Repository, repoDir)
+	if exitCode != 0 {
+		return fmt.Errorf("git clone returned %d, output: %v", exitCode, string(out))
+	}
+
+	err := os.Chdir(repoDir)
+	if err != nil {
+		return fmt.Errorf("changing to repository directory: %w", err)
+	}
+
+	if g.Ref != "" {
+		exitCode, out = execCommand("git", "fetch", "--depth=1", "origin", g.Ref)
+		if exitCode != 0 {
+			return fmt.Errorf("fetch clone returned %d, output: %v", exitCode, string(out))
+		}
+
+		exitCode, out = execCommand("git", "checkout", g.Ref)
+		if exitCode != 0 {
+			return fmt.Errorf("git checkout returned %d, output: %v", exitCode, string(out))
+		}
+	}
+
+	return nil
+}

internal/build/tarball.go

@@ -0,0 +1,68 @@
+package build
+
+import (
+	"archive/tar"
+	"bytes"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"runtime"
+)
+
+func (b *Builder) GenerateTarball() error {
+	buf := new(bytes.Buffer)
+
+	tarW := tar.NewWriter(buf)
+
+	err := tarW.WriteHeader(&tar.Header{
+		Name: "bin/",
+		Mode: int64(os.ModeDir) | 0o755,
+	})
+	if err != nil {
+		return fmt.Errorf("writing bin directory: %w", err)
+	}
+
+	for _, bin := range b.Binaries {
+		base := filepath.Base(bin)
+
+		binB, err := os.ReadFile(bin)
+		if err != nil {
+			return fmt.Errorf("reading binary %v: %w", bin, err)
+		}
+
+		err = tarW.WriteHeader(&tar.Header{
+			Name: filepath.Join("bin", base),
+			Size: int64(len(binB)),
+			Mode: 0o755,
+		})
+		if err != nil {
+			return fmt.Errorf("writing header for binary %v: %w", bin, err)
+		}
+
+		_, err = tarW.Write(binB)
+		if err != nil {
+			return fmt.Errorf("writing binary %v: %w", bin, err)
+		}
+	}
+
+	err = tarW.Close()
+	if err != nil {
+		return fmt.Errorf("writing tar footer: %w", err)
+	}
+
+	f, err := os.Create(filepath.Join(b.TempDir, fmt.Sprintf("%v-%v-%v.tar", b.Name, b.Version, runtime.GOARCH)))
+	if err != nil {
+		return fmt.Errorf("creating tarball: %w", err)
+	}
+	defer f.Close()
+
+	_, err = io.Copy(f, buf)
+	if err != nil {
+		return fmt.Errorf("writing to tarball: %w", err)
+	}
+
+	fmt.Println("wrote tarball at", f.Name())
+
+	return nil
+}