Add record segment duration to configuration and implement file rotation in recorder

config.yaml

@@ -1,2 +1,3 @@
 rtsp_url: "rtsp://10.10.10.104:8554/union"
 output_file: "output.wav"
+record_segment_duration: "30m"  # Duration for each recording segment

main.go

@@ -6,7 +6,10 @@ import (
 	"fmt"
 	"log/slog"
 	"os"
+	"path/filepath"
+	"strings"
 	"sync"
+	"time"
 
 	"github.com/bluenviron/gortsplib/v4"
 	"github.com/bluenviron/gortsplib/v4/pkg/base"
@@ -17,10 +20,11 @@ import (
 	"gopkg.in/yaml.v3"
 )
 
-// Config holds RTSP URL and output file path
+// Config holds RTSP URL, output file path, and rotation settings
 type Config struct {
-	RTSPURL    string `yaml:"rtsp_url"`
+	RTSPURL               string `yaml:"rtsp_url"`
-	OutputFile string `yaml:"output_file"`
+	OutputFile            string `yaml:"output_file"`
+	RecordSegmentDuration string `yaml:"record_segment_duration"` // Added
 }
 
 // Event represents lifecycle events (e.g., source ready, recording started)
@@ -44,17 +48,22 @@ type Data struct {
 	Pkt   *rtp.Packet
 }
 
-// Recorder saves packets to a file
+// Recorder saves packets to a file with rotation
 type Recorder struct {
-	name       string
+	name          string
-	path       *Path
+	path          *Path
-	file       *os.File
+	file          *os.File
-	writer     *bufio.Writer
+	writer        *bufio.Writer
-	isMuLaw    bool // true for μ-law, false for A-law
+	isMuLaw       bool // true for μ-law, false for A-law
-	dataChan   chan *Data
+	dataChan      chan *Data
-	terminate  chan struct{}
+	terminate     chan struct{}
-	sampleRate int
+	sampleRate    int
-	channels   int
+	channels      int
+	outputBase    string        // Base filename (without timestamp) // Added
+	segmentDur    time.Duration // Added
+	segmentStart  time.Time     // Added
+	totalDataSize uint32        // Added (moved from local variable)
+	fileMu        sync.Mutex    // Protects file operations // Added
 }
 
 // NewPath creates a stream hub
@@ -103,26 +112,38 @@ func (p *Path) SourceReady(audioMedia *description.Media, audioFormat format.For
 }
 
 // NewRecorder creates a recorder that subscribes to the path
-func NewRecorder(path *Path, outputFile string, isMuLaw bool) (*Recorder, error) {
+func NewRecorder(path *Path, outputFile string, isMuLaw bool, segmentDur time.Duration) (*Recorder, error) {
-	file, err := os.Create(outputFile)
+	// Initialize with a timestamped filename
+	fileName := formatFileName(outputFile, time.Now()) // Added
+	file, err := os.Create(fileName)                   // Modified
 	if err != nil {
-		return nil, fmt.Errorf("create file: %w", err)
+		return nil, fmt.Errorf("create file %s: %w", fileName, err) // Modified
 	}
 	r := &Recorder{
-		name:       "recorder",
+		name:         "recorder",
-		path:       path,
+		path:         path,
-		file:       file,
+		file:         file,
-		writer:     bufio.NewWriter(file),
+		writer:       bufio.NewWriter(file),
-		isMuLaw:    isMuLaw,
+		isMuLaw:      isMuLaw,
-		dataChan:   make(chan *Data, 100), // Buffered channel
+		dataChan:     make(chan *Data, 100), // Buffered channel
-		terminate:  make(chan struct{}),
+		terminate:    make(chan struct{}),
-		sampleRate: 8000, // Fixed for G.711
+		sampleRate:   8000,       // Fixed for G.711
-		channels:   1,    // Mono
+		channels:     1,          // Mono
+		outputBase:   outputFile, // Added
+		segmentDur:   segmentDur, // Added
+		segmentStart: time.Now(), // Added
 	}
 	path.AddReader(r.name, r.dataChan)
 	return r, nil
 }
 
+// formatFileName generates a timestamped filename (e.g., output_2025-08-19_10-24-00.wav)
+func formatFileName(baseName string, t time.Time) string {
+	ext := filepath.Ext(baseName)
+	name := strings.TrimSuffix(baseName, ext)
+	return fmt.Sprintf("%s_%s%s", name, t.Format("2006-01-02_15-04-05"), ext)
+}
+
 // writeWAVHeader writes a basic WAV header for PCM audio
 func (r *Recorder) writeWAVHeader(dataSize uint32) error {
 	header := make([]byte, 44)
@@ -143,6 +164,50 @@ func (r *Recorder) writeWAVHeader(dataSize uint32) error {
 	return err
 }
 
+// rotateFile closes the current file and opens a new one
+func (r *Recorder) rotateFile() error {
+	r.fileMu.Lock()
+	defer r.fileMu.Unlock()
+
+	// Flush and close current file
+	if err := r.writer.Flush(); err != nil {
+		return fmt.Errorf("flush file: %w", err)
+	}
+	if _, err := r.file.Seek(4, 0); err != nil {
+		return fmt.Errorf("seek file: %w", err)
+	}
+	var buf [4]byte
+	binary.LittleEndian.PutUint32(buf[:], 36+r.totalDataSize)
+	r.file.Write(buf[:])
+	if _, err := r.file.Seek(40, 0); err != nil {
+		return fmt.Errorf("seek file: %w", err)
+	}
+	binary.LittleEndian.PutUint32(buf[:], r.totalDataSize)
+	r.file.Write(buf[:])
+	if err := r.file.Close(); err != nil {
+		return fmt.Errorf("close file: %w", err)
+	}
+
+	// Open new file
+	fileName := formatFileName(r.outputBase, time.Now())
+	file, err := os.Create(fileName)
+	if err != nil {
+		return fmt.Errorf("create new file %s: %w", fileName, err)
+	}
+	r.file = file
+	r.writer = bufio.NewWriter(file)
+	r.totalDataSize = 0
+	r.segmentStart = time.Now()
+
+	// Write new WAV header
+	if err := r.writeWAVHeader(0); err != nil {
+		return fmt.Errorf("write new header: %w", err)
+	}
+	slog.Info("Rotated to new file", "filename", fileName)
+	r.path.eventChan <- Event{Type: "segment_complete", Data: fileName}
+	return nil
+}
+
 // muLawToPCM converts μ-law samples to 16-bit PCM
 func muLawToPCM(sample byte) int16 {
 	const muLawBias = 33
@@ -193,7 +258,7 @@ func (r *Recorder) Start() {
 	if err := r.writeWAVHeader(0); err != nil {
 		slog.Error("Write header error", "error", err)
 	}
-	var totalDataSize uint32
+	r.totalDataSize = 0 // Moved from local variable to struct field
 
 	go func() {
 		defer r.file.Close()
@@ -202,6 +267,13 @@ func (r *Recorder) Start() {
 			select {
 			case data := <-r.dataChan:
 				if data.Media.Type == "audio" {
+					// Check for rotation
+					if time.Since(r.segmentStart) >= r.segmentDur { // Added
+						if err := r.rotateFile(); err != nil {
+							slog.Error("File rotation error", "error", err)
+						}
+					}
+
 					// Unmarshal G.711 payload
 					var samples []byte
 					var err error
@@ -219,6 +291,7 @@ func (r *Recorder) Start() {
 						continue
 					}
 					// Convert to 16-bit PCM and write
+					r.fileMu.Lock() // Added
 					for _, sample := range samples {
 						var pcmSample int16
 						if r.isMuLaw {
@@ -232,11 +305,13 @@ func (r *Recorder) Start() {
 						if err != nil {
 							slog.Error("Write error", "error", err)
 						}
-						totalDataSize += 2
+						r.totalDataSize += 2
 					}
+					r.fileMu.Unlock() // Added
 				}
 			case <-r.terminate:
-				// Update WAV header with actual data size
+				// Update WAV header with final data size
+				r.fileMu.Lock() // Added
 				if err := r.writer.Flush(); err != nil {
 					slog.Error("Flush error", "error", err)
 				}
@@ -245,14 +320,15 @@ func (r *Recorder) Start() {
 					return
 				}
 				var buf [4]byte
-				binary.LittleEndian.PutUint32(buf[:], 36+totalDataSize)
+				binary.LittleEndian.PutUint32(buf[:], 36+r.totalDataSize)
 				r.file.Write(buf[:])
 				if _, err := r.file.Seek(40, 0); err != nil {
 					slog.Error("Seek error", "error", err)
 					return
 				}
-				binary.LittleEndian.PutUint32(buf[:], totalDataSize)
+				binary.LittleEndian.PutUint32(buf[:], r.totalDataSize)
 				r.file.Write(buf[:])
+				r.fileMu.Unlock() // Added
 				return
 			}
 		}
@@ -285,6 +361,16 @@ func main() {
 		os.Exit(1)
 	}
 
+	segmentDur := 5 * time.Minute
+	if conf.RecordSegmentDuration != "" {
+		dur, err := time.ParseDuration(conf.RecordSegmentDuration)
+		if err != nil {
+			slog.Error("Invalid record_segment_duration", "value", conf.RecordSegmentDuration, "error", err)
+			os.Exit(1)
+		}
+		segmentDur = dur
+	}
+
 	// Step 2: Set up event bus
 	eventChan := make(chan Event, 10)
 	go func() {
@@ -343,7 +429,7 @@ func main() {
 
 	// Step 5: Set up recorder (choose μ-law or A-law based on format)
 	isMuLaw := audioFormat.MULaw
-	recorder, err := NewRecorder(path, conf.OutputFile, isMuLaw)
+	recorder, err := NewRecorder(path, conf.OutputFile, isMuLaw, segmentDur) // Modified: added segmentDur
 	if err != nil {
 		slog.Error("Create recorder", "error", err)
 		os.Exit(1)