Files
sanderling/internal/trace/writer.go
T
pj 72c4e4c4d3 feat(trace): JSONL writer for steps + meta + screenshots
Each WriteStep appends one JSON object per line so the trace can
be filtered with jq directly. Screenshots land under screenshots/
with zero-padded indexes. Writer is concurrency-safe; Close is
idempotent and a write after Close errors loudly rather than
silently dropping.
2026-04-17 23:43:45 +07:00

105 lines
2.7 KiB
Go

package trace
import (
"encoding/json"
"fmt"
"io"
"os"
"path/filepath"
"sync"
"time"
)
type Step struct {
Index int `json:"step"`
Timestamp time.Time `json:"timestamp"`
Screen string `json:"screen,omitempty"`
Snapshots map[string]json.RawMessage `json:"snapshots,omitempty"`
Action *Action `json:"action,omitempty"`
Violations []string `json:"violations,omitempty"`
}
type Action struct {
Kind string `json:"kind"`
X int `json:"x,omitempty"`
Y int `json:"y,omitempty"`
Text string `json:"text,omitempty"`
}
type Meta struct {
Seed int64 `json:"seed"`
SpecPath string `json:"spec_path"`
BundleSHA256 string `json:"bundle_sha256"`
Platform string `json:"platform"`
BundleID string `json:"bundle_id"`
StartedAt time.Time `json:"started_at"`
UatuVersion string `json:"uatu_version"`
}
type Writer struct {
directory string
mutex sync.Mutex
file io.WriteCloser
encoder *json.Encoder
}
// NewWriter ensures `directory` exists and opens trace.jsonl for append.
// meta.json is written separately via WriteMeta. Caller must Close.
func NewWriter(directory string) (*Writer, error) {
if err := os.MkdirAll(directory, 0o755); err != nil {
return nil, fmt.Errorf("mkdir: %w", err)
}
file, err := os.OpenFile(
filepath.Join(directory, "trace.jsonl"),
os.O_CREATE|os.O_WRONLY|os.O_APPEND,
0o644,
)
if err != nil {
return nil, fmt.Errorf("open trace.jsonl: %w", err)
}
encoder := json.NewEncoder(file)
return &Writer{directory: directory, file: file, encoder: encoder}, nil
}
func (w *Writer) Directory() string { return w.directory }
func (w *Writer) WriteMeta(meta Meta) error {
body, err := json.MarshalIndent(meta, "", " ")
if err != nil {
return fmt.Errorf("marshal meta: %w", err)
}
return os.WriteFile(filepath.Join(w.directory, "meta.json"), body, 0o644)
}
func (w *Writer) WriteStep(step Step) error {
w.mutex.Lock()
defer w.mutex.Unlock()
if w.file == nil {
return fmt.Errorf("trace: writer is closed")
}
return w.encoder.Encode(step)
}
func (w *Writer) WriteScreenshot(stepIndex int, png []byte) error {
if len(png) == 0 {
return nil
}
directory := filepath.Join(w.directory, "screenshots")
if err := os.MkdirAll(directory, 0o755); err != nil {
return fmt.Errorf("mkdir screenshots: %w", err)
}
path := filepath.Join(directory, fmt.Sprintf("step-%05d.png", stepIndex))
return os.WriteFile(path, png, 0o644)
}
func (w *Writer) Close() error {
w.mutex.Lock()
defer w.mutex.Unlock()
if w.file == nil {
return nil
}
err := w.file.Close()
w.file = nil
return err
}