Additions to domain/ and workspace/ chron-note packages

chron-note/cmd/chron-note/main.go

@@ -1,3 +1,81 @@
 package main
 
-func main() {}
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"git.michelsen.id/phill/chron/chron-note/internal/domain"
+	"git.michelsen.id/phill/chron/chron-note/internal/workspace"
+)
+
+func must(err error) {
+	if err != nil {
+		panic(err)
+	}
+}
+
+func main() {
+	root := "."
+
+	if len(os.Args) > 1 {
+		root = os.Args[1]
+	}
+
+	ws, err := workspace.Open(root)
+	must(err)
+
+	fmt.Println("Workspace directory:")
+	fmt.Println(ws.Dir)
+	fmt.Println()
+
+	fmt.Println("Creating objects...")
+
+	var ids []domain.ObjectID
+
+	for i := range 3 {
+		id, err := domain.NewObjectID()
+		must(err)
+
+		content := fmt.Sprintf("object %d\nid: %s\n", i, id.String())
+
+		must(ws.Write(id, []byte(content)))
+
+		ids = append(ids, id)
+
+		fmt.Printf("Created object %s\n", id)
+		fmt.Printf("Path: %s\n\n", ws.ObjectPath(id))
+	}
+
+	fmt.Println("Listing workspace objects:")
+	fmt.Println()
+
+	list, err := ws.ListObjectIDs()
+	must(err)
+
+	for _, id := range list {
+		fi, err := ws.Stat(id)
+		must(err)
+
+		fmt.Printf("Object: %s\n", id)
+		fmt.Printf("Size:   %d bytes\n", fi.Size())
+		fmt.Printf("Path:   %s\n", ws.ObjectPath(id))
+		fmt.Println()
+	}
+
+	fmt.Println("Reading objects back:")
+	fmt.Println()
+
+	for _, id := range ids {
+		data, err := ws.Read(id)
+		must(err)
+
+		fmt.Printf("Object %s contents:\n", id)
+		fmt.Println(string(data))
+		fmt.Println("---")
+	}
+
+	fmt.Println()
+	fmt.Println("Filesystem view:")
+	fmt.Println(filepath.Join(ws.Dir, "..."))
+}

chron-note/internal/domain/errors.go

@@ -1,2 +1,11 @@
 package domain
 
+import "errors"
+
+var (
+	ErrInvalidObjectID  = errors.New("invalid object id")
+	ErrInvalidBlobID    = errors.New("invalid blob id")
+	ErrUnknownEventType = errors.New("unknown event type")
+	ErrInvalidEvent     = errors.New("invalid event")
+	ErrDecode           = errors.New("decode error")
+)

chron-note/internal/domain/event.go

@@ -1 +1,137 @@
 package domain
+
+import (
+	"fmt"
+
+	"git.michelsen.id/phill/chron/chron-note/internal/util"
+)
+
+type EventType uint8
+
+const (
+	EventObjectUpsert EventType = 1
+	EventObjectDelete EventType = 2
+)
+
+const encodingVersion uint8 = 1
+
+type ObjectUpsert struct {
+	ObjectID ObjectID
+	Name     string
+	Tags     []string
+
+	HasBlob bool
+	Blob    BlobID
+}
+
+type ObjectDelete struct {
+	ObjectID ObjectID
+}
+
+type Event struct {
+	Type EventType
+
+	Upsert *ObjectUpsert
+	Delete *ObjectDelete
+}
+
+func EncodeEvent(e Event) ([]byte, error) {
+	enc := util.NewEncoder(nil)
+	enc.U8(encodingVersion)
+	enc.U8(uint8(e.Type))
+
+	switch e.Type {
+	case EventObjectUpsert:
+		if e.Upsert == nil {
+			return nil, ErrInvalidEvent
+		}
+		u := e.Upsert
+
+		var flags uint8
+		if u.HasBlob {
+			flags |= 0x01
+		}
+		enc.U8(flags)
+
+		enc.BytesFixed(u.ObjectID[:])
+		enc.String(u.Name)
+		enc.StringSlice(u.Tags)
+
+		if u.HasBlob {
+			enc.BytesFixed(u.Blob[:])
+		}
+
+	case EventObjectDelete:
+		if e.Delete == nil {
+			return nil, ErrInvalidEvent
+		}
+		enc.BytesFixed(e.Delete.ObjectID[:])
+
+	default:
+		return nil, ErrUnknownEventType
+	}
+
+	if err := enc.Err(); err != nil {
+		return nil, err
+	}
+	return enc.Bytes(), nil
+}
+
+func DecodeEvent(b []byte) (Event, error) {
+	dec := util.NewDecoder(b)
+
+	ver := dec.U8()
+	if dec.Err() != nil {
+		return Event{}, ErrDecode
+	}
+	if ver != encodingVersion {
+		return Event{}, fmt.Errorf("%w: unsupported encoding version %d", ErrDecode, ver)
+	}
+
+	typ := EventType(dec.U8())
+	if dec.Err() != nil {
+		return Event{}, ErrDecode
+	}
+
+	switch typ {
+	case EventObjectUpsert:
+		flags := dec.U8()
+		var objID ObjectID
+		copy(objID[:], dec.BytesFixed(len(objID)))
+
+		name := dec.String()
+		tags := dec.StringSlice()
+
+		hasBlob := (flags & 0x01) != 0
+		var blob BlobID
+		if hasBlob {
+			copy(blob[:], dec.BytesFixed(len(blob)))
+		}
+
+		if dec.Err() != nil {
+			return Event{}, ErrDecode
+		}
+
+		return Event{
+			Type: typ,
+			Upsert: &ObjectUpsert{
+				ObjectID: objID,
+				Name:     NormalizeName(name),
+				Tags:     NormalizeTags(tags),
+				HasBlob:  hasBlob,
+				Blob:     blob,
+			},
+		}, nil
+
+	case EventObjectDelete:
+		var objID ObjectID
+		copy(objID[:], dec.BytesFixed(len(objID)))
+		if dec.Err() != nil {
+			return Event{}, ErrDecode
+		}
+		return Event{Type: typ, Delete: &ObjectDelete{ObjectID: objID}}, nil
+
+	default:
+		return Event{}, ErrUnknownEventType
+	}
+}

chron-note/internal/domain/object.go

@@ -1 +1,74 @@
 package domain
+
+import (
+	"crypto/rand"
+	"encoding/hex"
+	"strings"
+)
+
+type ObjectID [16]byte
+type BlobID [32]byte
+
+func NewObjectID() (ObjectID, error) {
+	var id ObjectID
+	_, err := rand.Read(id[:])
+	return id, err
+}
+
+func ParseObjectID(s string) (ObjectID, error) {
+	s = strings.TrimSpace(s)
+	b, err := hex.DecodeString(s)
+	if err != nil || len(b) != len(ObjectID{}) {
+		return ObjectID{}, ErrInvalidObjectID
+	}
+	var id ObjectID
+	copy(id[:], b)
+	return id, nil
+}
+
+func (id ObjectID) String() string { return hex.EncodeToString(id[:]) }
+
+func ParseBlobID(s string) (BlobID, error) {
+	s = strings.TrimSpace(s)
+	b, err := hex.DecodeString(s)
+	if err != nil || len(b) != len(BlobID{}) {
+		return BlobID{}, ErrInvalidBlobID
+	}
+	var id BlobID
+	copy(id[:], b)
+	return id, nil
+}
+
+func (id BlobID) String() string { return hex.EncodeToString(id[:]) }
+
+type ObjectState struct {
+	ID      ObjectID
+	Name    string
+	Tags    []string
+	Blob    BlobID
+	HasBlob bool
+	Deleted bool
+}
+
+// Keep normalization here so all layers agree.
+func NormalizeName(s string) string {
+	s = strings.TrimSpace(s)
+	return s
+}
+
+func NormalizeTags(tags []string) []string {
+	out := make([]string, 0, len(tags))
+	seen := make(map[string]struct{}, len(tags))
+	for _, t := range tags {
+		t = strings.TrimSpace(strings.ToLower(t))
+		if t == "" {
+			continue
+		}
+		if _, ok := seen[t]; ok {
+			continue
+		}
+		seen[t] = struct{}{}
+		out = append(out, t)
+	}
+	return out
+}

chron-note/internal/index/index.go

@@ -1 +0,0 @@
-package index

chron-note/internal/index/registry.go

@@ -1 +0,0 @@
-package index

chron-note/internal/state/reduce.go

@@ -0,0 +1 @@
+package state

chron-note/internal/state/state.go

@@ -0,0 +1 @@
+package state

chron-note/internal/stores/cas/cas.go

@@ -0,0 +1,14 @@
+package cas
+
+import (
+	"context"
+
+	"git.michelsen.id/phill/chron/chron-note/internal/domain"
+)
+
+type Store interface {
+	Put(ctx context.Context, data []byte) (domain.BlobID, error) // id = blake3-256(data)
+	Get(ctx context.Context, id domain.BlobID) ([]byte, error)
+	Has(ctx context.Context, id domain.BlobID) (bool, error)
+	Remove(ctx context.Context, id domain.BlobID) error
+}

chron-note/internal/stores/cas/fs.go

@@ -0,0 +1,93 @@
+package cas
+
+import (
+	"context"
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"git.michelsen.id/phill/chron/chron-note/internal/domain"
+	"git.michelsen.id/phill/chron/chron-note/internal/util"
+)
+
+var ErrBlobNotFound = errors.New("blob not found")
+
+type FS struct {
+	root string
+}
+
+func NewFS(root string) *FS {
+	return &FS{root: root}
+}
+
+func (s *FS) Put(ctx context.Context, data []byte) (domain.BlobID, error) {
+	_ = ctx
+
+	sum := util.Hash256(data)
+	var id domain.BlobID
+	copy(id[:], sum[:])
+
+	p := s.pathFor(id)
+
+	// Fast path: already exists
+	if _, err := os.Stat(p); err == nil {
+		return id, nil
+	}
+
+	if err := os.MkdirAll(filepath.Dir(p), 0o755); err != nil {
+		return domain.BlobID{}, err
+	}
+
+	tmp := p + ".tmp"
+	if err := os.WriteFile(tmp, data, 0o644); err != nil {
+		return domain.BlobID{}, err
+	}
+	if err := os.Rename(tmp, p); err != nil {
+		_ = os.Remove(tmp)
+		// If another writer won the race, accept it.
+		if _, statErr := os.Stat(p); statErr == nil {
+			return id, nil
+		}
+		return domain.BlobID{}, err
+	}
+
+	return id, nil
+}
+
+func (s *FS) Get(ctx context.Context, id domain.BlobID) ([]byte, error) {
+	_ = ctx
+	p := s.pathFor(id)
+	b, err := os.ReadFile(p)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil, ErrBlobNotFound
+		}
+		return nil, err
+	}
+	return b, nil
+}
+
+func (s *FS) Has(ctx context.Context, id domain.BlobID) (bool, error) {
+	_ = ctx
+	p := s.pathFor(id)
+	_, err := os.Stat(p)
+	if err == nil {
+		return true, nil
+	}
+	if os.IsNotExist(err) {
+		return false, nil
+	}
+	return false, err
+}
+
+func (s *FS) pathFor(id domain.BlobID) string {
+	hexID := hex.EncodeToString(id[:])
+	if len(hexID) < 4 {
+		// should never happen
+		return filepath.Join(s.root, fmt.Sprintf("bad-%s", hexID))
+	}
+	// git-style fanout
+	return filepath.Join(s.root, hexID[:2], hexID[2:4], hexID)
+}

chron-note/internal/util/encoding.go

@@ -1 +1,133 @@
 package util
+
+import (
+	"encoding/binary"
+	"errors"
+)
+
+var ErrDecode = errors.New("decode")
+
+type Encoder struct {
+	b   []byte
+	err error
+}
+
+func NewEncoder(dst []byte) *Encoder { return &Encoder{b: dst} }
+func (e *Encoder) Bytes() []byte     { return e.b }
+func (e *Encoder) Err() error        { return e.err }
+
+func (e *Encoder) U8(v uint8) {
+	if e.err != nil {
+		return
+	}
+	e.b = append(e.b, v)
+}
+
+func (e *Encoder) U32(v uint32) {
+	if e.err != nil {
+		return
+	}
+	var tmp [4]byte
+	binary.LittleEndian.PutUint32(tmp[:], v)
+	e.b = append(e.b, tmp[:]...)
+}
+
+func (e *Encoder) BytesFixed(p []byte) {
+	if e.err != nil {
+		return
+	}
+	e.b = append(e.b, p...)
+}
+
+func (e *Encoder) BytesLen(p []byte) {
+	if e.err != nil {
+		return
+	}
+	e.U32(uint32(len(p)))
+	e.b = append(e.b, p...)
+}
+
+func (e *Encoder) String(s string) {
+	e.BytesLen([]byte(s))
+}
+
+func (e *Encoder) StringSlice(ss []string) {
+	if e.err != nil {
+		return
+	}
+	e.U32(uint32(len(ss)))
+	for _, s := range ss {
+		e.String(s)
+	}
+}
+
+type Decoder struct {
+	b   []byte
+	off int
+	err error
+}
+
+func NewDecoder(src []byte) *Decoder { return &Decoder{b: src} }
+func (d *Decoder) Err() error        { return d.err }
+
+func (d *Decoder) need(n int) bool {
+	if d.err != nil {
+		return false
+	}
+	if n < 0 || d.off+n > len(d.b) {
+		d.err = ErrDecode
+		return false
+	}
+	return true
+}
+
+func (d *Decoder) U8() uint8 {
+	if !d.need(1) {
+		return 0
+	}
+	v := d.b[d.off]
+	d.off++
+	return v
+}
+
+func (d *Decoder) U32() uint32 {
+	if !d.need(4) {
+		return 0
+	}
+	v := binary.LittleEndian.Uint32(d.b[d.off : d.off+4])
+	d.off += 4
+	return v
+}
+
+func (d *Decoder) BytesFixed(n int) []byte {
+	if !d.need(n) {
+		return nil
+	}
+	out := d.b[d.off : d.off+n]
+	d.off += n
+	return out
+}
+
+func (d *Decoder) BytesLen() []byte {
+	n := int(d.U32())
+	return d.BytesFixed(n)
+}
+
+func (d *Decoder) String() string {
+	return string(d.BytesLen())
+}
+
+func (d *Decoder) StringSlice() []string {
+	n := int(d.U32())
+	if d.Err() != nil {
+		return nil
+	}
+	out := make([]string, 0, n)
+	for range n {
+		out = append(out, d.String())
+		if d.Err() != nil {
+			return nil
+		}
+	}
+	return out
+}

chron-note/internal/util/hash.go

@@ -1 +1,8 @@
 package util
+
+import "lukechampine.com/blake3"
+
+func Hash256(b []byte) [32]byte {
+	h := blake3.Sum256(b)
+	return h
+}

chron-note/internal/workspace/io.go

@@ -0,0 +1,69 @@
+package workspace
+
+import (
+	"fmt"
+	"os"
+
+	"git.michelsen.id/phill/chron/chron-note/internal/domain"
+)
+
+func (ws *Workspace) Exists(id domain.ObjectID) (bool, error) {
+	_, err := os.Stat(ws.ObjectPath(id))
+	if err == nil {
+		return true, nil
+	}
+	if os.IsNotExist(err) {
+		return false, nil
+	}
+	return false, fmt.Errorf("stat object %s: %w", id.String(), err)
+}
+
+func (ws *Workspace) Read(id domain.ObjectID) ([]byte, error) {
+	b, err := os.ReadFile(ws.ObjectPath(id))
+	if err != nil {
+		return nil, fmt.Errorf("read object %s: %w", id.String(), err)
+	}
+	return b, nil
+}
+
+func (ws *Workspace) Write(id domain.ObjectID, b []byte) error {
+	if err := os.MkdirAll(ws.Dir, 0o755); err != nil {
+		return fmt.Errorf("mkdir workspace dir: %w", err)
+	}
+
+	dst := ws.ObjectPath(id)
+
+	f, err := os.CreateTemp(ws.Dir, id.String()+".*.tmp")
+	if err != nil {
+		return fmt.Errorf("create temp for object %s: %w", id.String(), err)
+	}
+	tmp := f.Name()
+
+	// Best-effort cleanup on failure.
+	defer func() { _ = os.Remove(tmp) }()
+
+	if _, err := f.Write(b); err != nil {
+		_ = f.Close()
+		return fmt.Errorf("write temp for object %s: %w", id.String(), err)
+	}
+	if err := f.Close(); err != nil {
+		return fmt.Errorf("close temp for object %s: %w", id.String(), err)
+	}
+
+	if err := os.Rename(tmp, dst); err != nil {
+		return fmt.Errorf("rename temp for object %s: %w", id.String(), err)
+	}
+
+	// Rename succeeded; prevent deferred cleanup.
+	_ = os.Remove(tmp)
+	return nil
+}
+
+func (ws *Workspace) Delete(id domain.ObjectID) error {
+	p := ws.ObjectPath(id)
+	err := os.Remove(p)
+	if err == nil || os.IsNotExist(err) {
+		return nil
+	}
+	return fmt.Errorf("delete object %s: %w", id.String(), err)
+}

chron-note/internal/workspace/list.go

@@ -0,0 +1,46 @@
+package workspace
+
+import (
+	"fmt"
+	"io/fs"
+	"os"
+
+	"git.michelsen.id/phill/chron/chron-note/internal/domain"
+)
+
+func (ws *Workspace) ListObjectIDs() ([]domain.ObjectID, error) {
+	entries, err := os.ReadDir(ws.Dir)
+	if err != nil {
+		return nil, fmt.Errorf("readdir workspace dir: %w", err)
+	}
+
+	out := make([]domain.ObjectID, 0, len(entries))
+	for _, e := range entries {
+		if e.IsDir() {
+			continue
+		}
+		info, err := e.Info()
+		if err != nil {
+			return nil, fmt.Errorf("stat workspace entry: %w", err)
+		}
+		if !info.Mode().IsRegular() {
+			continue
+		}
+
+		id, err := domain.ParseObjectID(e.Name())
+		if err != nil {
+			continue
+		}
+		out = append(out, id)
+	}
+
+	return out, nil
+}
+
+func (ws *Workspace) Stat(id domain.ObjectID) (fs.FileInfo, error) {
+	fi, err := os.Stat(ws.ObjectPath(id))
+	if err != nil {
+		return nil, fmt.Errorf("stat object %s: %w", id.String(), err)
+	}
+	return fi, nil
+}

chron-note/internal/workspace/snapshot.go

@@ -0,0 +1,52 @@
+package workspace
+
+import (
+	"context"
+	"fmt"
+	"os"
+
+	"git.michelsen.id/phill/chron/chron-note/internal/domain"
+)
+
+type SnapshotObject struct {
+	ID    domain.ObjectID
+	Size  int64
+	ModNS int64
+}
+
+func (ws *Workspace) Snapshot(ctx context.Context) ([]SnapshotObject, error) {
+	entries, err := os.ReadDir(ws.Dir)
+	if err != nil {
+		return nil, fmt.Errorf("readdir workspace dir: %w", err)
+	}
+
+	out := make([]SnapshotObject, 0, len(entries))
+	for _, e := range entries {
+		if ctx.Err() != nil {
+			return nil, ctx.Err()
+		}
+		if e.IsDir() {
+			continue
+		}
+		info, err := e.Info()
+		if err != nil {
+			return nil, fmt.Errorf("stat workspace entry: %w", err)
+		}
+		if !info.Mode().IsRegular() {
+			continue
+		}
+
+		id, err := domain.ParseObjectID(e.Name())
+		if err != nil {
+			continue
+		}
+
+		out = append(out, SnapshotObject{
+			ID:    id,
+			Size:  info.Size(),
+			ModNS: info.ModTime().UnixNano(),
+		})
+	}
+
+	return out, nil
+}

chron-note/internal/workspace/workspace.go

@@ -0,0 +1,32 @@
+package workspace
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"git.michelsen.id/phill/chron/chron-note/internal/domain"
+)
+
+type Workspace struct {
+	Root string
+	Dir  string
+}
+
+func Open(root string) (*Workspace, error) {
+	root = filepath.Clean(root)
+	dir := filepath.Join(root, ".chron", "workspace")
+
+	if err := os.MkdirAll(dir, 0o755); err != nil {
+		return nil, fmt.Errorf("mkdir workspace dir: %w", err)
+	}
+
+	return &Workspace{
+		Root: root,
+		Dir:  dir,
+	}, nil
+}
+
+func (ws *Workspace) ObjectPath(id domain.ObjectID) string {
+	return filepath.Join(ws.Dir, id.String())
+}