Initialize narratio Go module and CLI scaffold

internal/artifacts/checksum.go

@@ -0,0 +1,24 @@
+package artifacts
+
+import (
+	"crypto/sha256"
+	"encoding/hex"
+	"io"
+	"os"
+)
+
+// SHA256File returns the SHA-256 hex digest of a file.
+func SHA256File(path string) (string, error) {
+	f, err := os.Open(path)
+	if err != nil {
+		return "", err
+	}
+	defer f.Close()
+
+	h := sha256.New()
+	if _, err := io.Copy(h, f); err != nil {
+		return "", err
+	}
+
+	return hex.EncodeToString(h.Sum(nil)), nil
+}

internal/artifacts/doc.go

@@ -0,0 +1,2 @@
+// Package artifacts defines artifact references and storage contracts.
+package artifacts

internal/artifacts/local.go

@@ -0,0 +1,31 @@
+package artifacts
+
+import (
+	"context"
+	"fmt"
+)
+
+// LocalStore is a placeholder local filesystem artifact store.
+type LocalStore struct {
+	RootDir string
+}
+
+// WriteLocal returns a not-yet-implemented error in the scaffold.
+func (s *LocalStore) WriteLocal(_ context.Context, _ Ref, _ []byte) error {
+	return fmt.Errorf("artifacts local write: not yet implemented")
+}
+
+// ReadLocal returns a not-yet-implemented error in the scaffold.
+func (s *LocalStore) ReadLocal(_ context.Context, _ Ref) ([]byte, error) {
+	return nil, fmt.Errorf("artifacts local read: not yet implemented")
+}
+
+// ExistsLocal returns a not-yet-implemented error in the scaffold.
+func (s *LocalStore) ExistsLocal(_ context.Context, _ Ref) (bool, error) {
+	return false, fmt.Errorf("artifacts local exists: not yet implemented")
+}
+
+// Upload returns a not-yet-implemented error in the scaffold.
+func (s *LocalStore) Upload(_ context.Context, _ Ref) (string, error) {
+	return "", fmt.Errorf("artifacts local upload: not yet implemented")
+}

internal/artifacts/paths.go

@@ -0,0 +1,8 @@
+package artifacts
+
+import "path/filepath"
+
+// SessionWorkDir returns the work directory for one session.
+func SessionWorkDir(rootDir, sessionID string) string {
+	return filepath.Join(rootDir, "work", sessionID)
+}

internal/artifacts/s3.go

@@ -0,0 +1,32 @@
+package artifacts
+
+import (
+	"context"
+	"fmt"
+)
+
+// S3Store is a placeholder S3-compatible artifact store.
+type S3Store struct {
+	Bucket string
+	Prefix string
+}
+
+// WriteLocal returns a not-yet-implemented error in the scaffold.
+func (s *S3Store) WriteLocal(_ context.Context, _ Ref, _ []byte) error {
+	return fmt.Errorf("artifacts s3 write local: not yet implemented")
+}
+
+// ReadLocal returns a not-yet-implemented error in the scaffold.
+func (s *S3Store) ReadLocal(_ context.Context, _ Ref) ([]byte, error) {
+	return nil, fmt.Errorf("artifacts s3 read local: not yet implemented")
+}
+
+// ExistsLocal returns a not-yet-implemented error in the scaffold.
+func (s *S3Store) ExistsLocal(_ context.Context, _ Ref) (bool, error) {
+	return false, fmt.Errorf("artifacts s3 exists local: not yet implemented")
+}
+
+// Upload returns a not-yet-implemented error in the scaffold.
+func (s *S3Store) Upload(_ context.Context, _ Ref) (string, error) {
+	return "", fmt.Errorf("artifacts s3 upload: not yet implemented")
+}

internal/artifacts/store.go

@@ -0,0 +1,19 @@
+package artifacts
+
+import "context"
+
+// Ref identifies a pipeline artifact and optional remote location.
+type Ref struct {
+	Kind      string
+	LocalPath string
+	RemoteKey string
+	Checksum  string
+}
+
+// Store is a placeholder artifact storage abstraction.
+type Store interface {
+	WriteLocal(ctx context.Context, ref Ref, data []byte) error
+	ReadLocal(ctx context.Context, ref Ref) ([]byte, error)
+	ExistsLocal(ctx context.Context, ref Ref) (bool, error)
+	Upload(ctx context.Context, ref Ref) (string, error)
+}