HLS: Support low latency mode about 5s. v5.13.7

DEVELOPER.md

@@ -885,6 +885,8 @@ Platform, with token authentication:
 * `/terraform/v1/mgmt/secret/query` Query the api secret for OpenAPI.
 * `/terraform/v1/mgmt/hphls/update` HLS delivery in high performance mode.
 * `/terraform/v1/mgmt/hphls/query` Query HLS delivery in high performance mode.
+* `/terraform/v1/mgmt/hlsll/update` Setup HLS low latency mode.
+* `/terraform/v1/mgmt/hlsll/query` Query state of HLS low latency mode.
 * `/terraform/v1/mgmt/ssl` Config the system SSL config.
 * `/terraform/v1/mgmt/auto-self-signed-certificate` Create the self-signed certificate if no cert.
 * `/terraform/v1/mgmt/letsencrypt` Config the let's encrypt SSL.
@@ -1062,6 +1064,7 @@ The following are the update records for the SRS Stack server.
     * Fix bug: Remove HTTP port for SRS. v5.13.4
     * Refine API with Bearer token. v5.13.5
     * Switch to fluid max width. v5.13.6
+    * HLS: Support low latency mode about 5s. v5.13.7
 * v5.12
     * Refine local variable name conf to config. v5.12.1
     * Add forced exit on timeout for program termination. v5.12.1
@@ -1083,6 +1086,7 @@ The following are the update records for the SRS Stack server.
     * Transcript: Support clear the subtitle of segment in fixing queue. [v5.12.15](https://github.com/ossrs/srs-stack/releases/tag/v5.12.15)
     * VLive: Fix bug for url with query string. v5.12.16
     * Transcript: Check the base url for OpenAI. [v5.12.17](https://github.com/ossrs/srs-stack/releases/tag/v5.12.17)
+    * HLS: Support low latency mode about 5s. v5.12.18
 * v5.11
     * VLive: Decrease the latency for virtual live. v5.11.1
     * Live: Refine multiple language. v5.11.2

platform/containers/www/tools/player.html

@@ -13,43 +13,74 @@
   <video id="player" autoplay controls muted></video>
 </body>
 <script type="text/javascript" src="js/jquery-1.10.2.min.js"></script>
-<script type="text/javascript" src="js/flv-1.5.0.min.js"></script>
-<script type="text/javascript" src="js/hls-0.14.17.min.js"></script>
+<script type="text/javascript" src="js/mpegts-1.7.3.min.js"></script>
+<script type="text/javascript" src="js/hls-1.4.14.min.js"></script>
 <script type="text/javascript">
   $(function(){
     // See https://developer.mozilla.org/en-US/docs/Web/API/URLSearchParams
     const q = new URLSearchParams(location.search);
 
     const resource = q.get('url');
-    if (!resource) return alert(`没有指定URL`);
+    if (!resource) return alert(`No URL`);
 
-    if (resource.indexOf('.flv') > 0) {
-      if (!flvjs.isSupported()) return alert(`你的浏览器不支持HTTP-FLV`);
+    const video = document.getElementById('player');
+    if (resource.indexOf('.m3u8') > 0) {
+      if (!Hls.isSupported()) {
+        // See https://stackoverflow.com/a/12905122/17679565
+        if (document.createElement('video').canPlayType('application/vnd.apple.mpegURL')) {
+          console.log(`Play by native for ${resource}`);
+          $('#player').prop('src', resource);
+          return;
+        }
+        return alert(`HLS is not supported, url is ${resource}`);
+      }
 
-      const player = flvjs.createPlayer({type: 'flv', url: resource});
-      player.attachMediaElement(document.getElementById('player'));
-      player.load();
-      player.play();
-      console.log(`Play by flv.js for ${resource}`);
+      // See https://github.com/video-dev/hls.js/blob/master/docs/API.md#maxlivesyncplaybackrate
+      // See https://github.com/video-dev/hls.js/issues/3077#issuecomment-705152394
+      const player = new Hls({
+        enableWorker: true, // Improve performance and avoid lag/frame drops.
+        lowLatencyMode: true, // Enable Low-Latency HLS part playlist and segment loading.
+        liveSyncDurationCount: 0, // Start from the last segment.
+        liveMaxLatencyDurationCount: 4, // Maximum delay allowed from edge of live.
+        maxBufferLength: 5, // Maximum buffer length in seconds.
+        maxMaxBufferLength: 8, // The max Maximum buffer length in seconds.
+        maxLiveSyncPlaybackRate: 2, // Catch up if the latency is large.
+        liveDurationInfinity: true // Override current Media Source duration to Infinity for a live broadcast.
+      });
+      player.loadSource(resource);
+      player.attachMedia(video);
+      video.play();
+      console.log(`Play by hls.js for ${resource}`);
       return;
     }
 
-    if (resource.indexOf('.m3u8') > 0) {
-      // See https://stackoverflow.com/a/12905122/17679565
-      if (document.createElement('video').canPlayType('application/vnd.apple.mpegURL')) {
-        console.log(`Play by native for ${resource}`);
-        $('#player').prop('src', resource);
-        return;
+    // Start play HTTP-FLV.
+    let isFlv = resource.indexOf('.flv') > 0;
+    // Compatible with NGINX-HTTP-FLV module, see https://github.com/winshining/nginx-http-flv-module and the stream
+    // url without .flv, such as:
+    //          http://localhost:8080/live?app=live&stream=livestream
+    isFlv = isFlv || resource && resource.indexOf('http') === 0;
+    if (isFlv) {
+      if (!mpegts.getFeatureList().mseLivePlayback) {
+        return alert(`HTTP-FLV is not supported, url is ${resource}`);
       }
 
-      const player = new Hls();
-      player.loadSource(resource);
-      player.attachMedia(document.getElementById('player'));
-      console.log(`Play by hls.js for ${resource}`);
+      // See https://github.com/xqq/mpegts.js/blob/master/src/config.js#L32
+      // See https://github.com/xqq/mpegts.js/blob/master/docs/api.md
+      const player = mpegts.createPlayer({
+        type: 'flv', url: resource,
+        isLive: true, enableStashBuffer: false, liveSync: true
+      });
+      player.attachMediaElement(video);
+      player.load();
+      player.play();
+      console.log(`Play by flv.js for ${resource}`);
       return;
     }
 
-    alert(`不支持的URL：${resource}`);
+    const msg = `Not supported URL ${resource}`;
+    console.error(msg);
+    alert(msg);
   });
 </script>
 </html>

platform/service.go

@@ -241,6 +241,8 @@ func handleHTTPService(ctx context.Context, handler *http.ServeMux) error {
 	handleMgmtBeianUpdate(ctx, handler)
 	handleMgmtNginxHlsUpdate(ctx, handler)
 	handleMgmtNginxHlsQuery(ctx, handler)
+	handleMgmtHlsLowLatencyUpdate(ctx, handler)
+	handleMgmtHlsLowLatencyQuery(ctx, handler)
 	handleMgmtAutoSelfSignedCertificate(ctx, handler)
 	handleMgmtSsl(ctx, handler)
 	handleMgmtLetsEncrypt(ctx, handler)
@@ -1078,6 +1080,84 @@ func handleMgmtNginxHlsQuery(ctx context.Context, handler *http.ServeMux) {
 	})
 }
 
+func handleMgmtHlsLowLatencyUpdate(ctx context.Context, handler *http.ServeMux) {
+	ep := "/terraform/v1/mgmt/hlsll/update"
+	logger.Tf(ctx, "Handle %v", ep)
+	handler.HandleFunc(ep, func(w http.ResponseWriter, r *http.Request) {
+		if err := func() error {
+			var token string
+			var hlsLowLatency bool
+			if err := ParseBody(ctx, r.Body, &struct {
+				Token         *string `json:"token"`
+				HlsLowLatency *bool   `json:"hlsLowLatency"`
+			}{
+				Token: &token, HlsLowLatency: &hlsLowLatency,
+			}); err != nil {
+				return errors.Wrapf(err, "parse body")
+			}
+
+			apiSecret := os.Getenv("SRS_PLATFORM_SECRET")
+			if err := Authenticate(ctx, apiSecret, token, r.Header); err != nil {
+				return errors.Wrapf(err, "authenticate")
+			}
+
+			hlsLowLatencyValue := fmt.Sprintf("%v", hlsLowLatency)
+			if err := rdb.HSet(ctx, SRS_LL_HLS, "hlsLowLatency", hlsLowLatencyValue).Err(); err != nil && err != redis.Nil {
+				return errors.Wrapf(err, "hset %v hlsLowLatency %v", SRS_LL_HLS, hlsLowLatencyValue)
+			}
+
+			if err := srsGenerateConfig(ctx); err != nil {
+				return errors.Wrapf(err, "generate SRS config")
+			}
+
+			ohttp.WriteData(ctx, w, r, nil)
+			logger.Tf(ctx, "hls low latency update ok, enabled=%v, token=%vB", hlsLowLatency, len(token))
+			return nil
+		}(); err != nil {
+			ohttp.WriteError(ctx, w, r, err)
+		}
+	})
+}
+
+func handleMgmtHlsLowLatencyQuery(ctx context.Context, handler *http.ServeMux) {
+	ep := "/terraform/v1/mgmt/hlsll/query"
+	logger.Tf(ctx, "Handle %v", ep)
+	handler.HandleFunc(ep, func(w http.ResponseWriter, r *http.Request) {
+		if err := func() error {
+			var token string
+			if err := ParseBody(ctx, r.Body, &struct {
+				Token *string `json:"token"`
+			}{
+				Token: &token,
+			}); err != nil {
+				return errors.Wrapf(err, "parse body")
+			}
+
+			apiSecret := os.Getenv("SRS_PLATFORM_SECRET")
+			if err := Authenticate(ctx, apiSecret, token, r.Header); err != nil {
+				return errors.Wrapf(err, "authenticate")
+			}
+
+			var enabled bool
+			if v, err := rdb.HGet(ctx, SRS_LL_HLS, "hlsLowLatency").Result(); err != nil && err != redis.Nil {
+				return errors.Wrapf(err, "hget %v %v", SRS_LL_HLS, "hlsLowLatency")
+			} else {
+				enabled = v == "true"
+			}
+
+			ohttp.WriteData(ctx, w, r, &struct {
+				HlsLowLatency bool `json:"hlsLowLatency"`
+			}{
+				HlsLowLatency: enabled,
+			})
+			logger.Tf(ctx, "hls low latency query ok, enabled=%v, token=%vB", enabled, len(token))
+			return nil
+		}(); err != nil {
+			ohttp.WriteError(ctx, w, r, err)
+		}
+	})
+}
+
 func handleMgmtAutoSelfSignedCertificate(ctx context.Context, handler *http.ServeMux) {
 	ep := "/terraform/v1/mgmt/auto-self-signed-certificate"
 	logger.Tf(ctx, "Handle %v", ep)

platform/utils.go

@@ -253,6 +253,7 @@ const (
 	SRS_TENCENT_LH = "SRS_TENCENT_LH"
 	// For SRS stream status.
 	SRS_HP_HLS = "SRS_HP_HLS"
+	SRS_LL_HLS = "SRS_LL_HLS"
 	// For tencent cloud products.
 	SRS_TENCENT_CAM = "SRS_TENCENT_CAM"
 	SRS_TENCENT_COS = "SRS_TENCENT_COS"
@@ -464,15 +465,30 @@ func srsGenerateConfig(ctx context.Context) error {
 		"",
 		"hls {",
 		"    enabled on;",
-		"    hls_fragment 10;",
-		"    hls_window 60;",
+	}
+	if hlsLowLatency, err := rdb.HGet(ctx, SRS_LL_HLS, "hlsLowLatency").Result(); err != nil && err != redis.Nil {
+		return errors.Wrapf(err, "hget %v hls", SRS_LL_HLS)
+	} else {
+		if hlsLowLatency != "true" {
+			hlsConf = append(hlsConf, []string{
+				"    hls_fragment 10;",
+				"    hls_window 60;",
+			}...)
+		} else {
+			hlsConf = append(hlsConf, []string{
+				"    hls_fragment 2;",
+				"    hls_window 12;",
+			}...)
+		}
+	}
+	hlsConf = append(hlsConf, []string{
 		"    hls_aof_ratio 2.1;",
 		"    hls_path ./objs/nginx/html;",
 		"    hls_m3u8_file [app]/[stream].m3u8;",
 		"    hls_ts_file [app]/[stream]-[seq]-[timestamp].ts;",
 		"    hls_wait_keyframe on;",
 		"    hls_dispose 10;",
-	}
+	}...)
 	if noHlsCtx, err := rdb.HGet(ctx, SRS_HP_HLS, "noHlsCtx").Result(); err != nil && err != redis.Nil {
 		return errors.Wrapf(err, "hget %v hls", SRS_HP_HLS)
 	} else if noHlsCtx == "true" {

test/api_test.go

@@ -425,6 +425,96 @@ func TestApi_SetupHpHLSWithHlsCtx(t *testing.T) {
 	}
 }
 
+func TestApi_SetupHlsLowLatencyEnable(t *testing.T) {
+	ctx, cancel := context.WithTimeout(logger.WithContext(context.Background()), time.Duration(*srsTimeout)*time.Millisecond)
+	defer cancel()
+
+	var r0 error
+	defer func(ctx context.Context) {
+		if err := filterTestError(ctx.Err(), r0); err != nil {
+			t.Errorf("Fail for err %+v", err)
+		} else {
+			logger.Tf(ctx, "test done")
+		}
+	}(ctx)
+
+	type Data struct {
+		HlsLowLatency bool `json:"hlsLowLatency"`
+	}
+
+	if true {
+		initData := Data{}
+		if err := NewApi().WithAuth(ctx, "/terraform/v1/mgmt/hlsll/query", nil, &initData); err != nil {
+			r0 = err
+			return
+		}
+		defer func() {
+			if err := NewApi().WithAuth(ctx, "/terraform/v1/mgmt/hlsll/update", &initData, nil); err != nil {
+				logger.Tf(ctx, "restore hlsll config failed %+v", err)
+			}
+		}()
+	}
+
+	hlsLowLatency := Data{HlsLowLatency: true}
+	if err := NewApi().WithAuth(ctx, "/terraform/v1/mgmt/hlsll/update", &hlsLowLatency, nil); err != nil {
+		r0 = err
+		return
+	}
+
+	verifyData := Data{}
+	if err := NewApi().WithAuth(ctx, "/terraform/v1/mgmt/hlsll/query", nil, &verifyData); err != nil {
+		r0 = err
+		return
+	} else if verifyData.HlsLowLatency != true {
+		r0 = errors.Errorf("invalid response %+v", verifyData)
+	}
+}
+
+func TestApi_SetupHlsLowLatencyDisable(t *testing.T) {
+	ctx, cancel := context.WithTimeout(logger.WithContext(context.Background()), time.Duration(*srsTimeout)*time.Millisecond)
+	defer cancel()
+
+	var r0 error
+	defer func(ctx context.Context) {
+		if err := filterTestError(ctx.Err(), r0); err != nil {
+			t.Errorf("Fail for err %+v", err)
+		} else {
+			logger.Tf(ctx, "test done")
+		}
+	}(ctx)
+
+	type Data struct {
+		HlsLowLatency bool `json:"hlsLowLatency"`
+	}
+
+	if true {
+		initData := Data{}
+		if err := NewApi().WithAuth(ctx, "/terraform/v1/mgmt/hlsll/query", nil, &initData); err != nil {
+			r0 = err
+			return
+		}
+		defer func() {
+			if err := NewApi().WithAuth(ctx, "/terraform/v1/mgmt/hlsll/update", &initData, nil); err != nil {
+				logger.Tf(ctx, "restore hlsll config failed %+v", err)
+			}
+		}()
+	}
+
+	hlsLowLatency := Data{HlsLowLatency: false}
+	if err := NewApi().WithAuth(ctx, "/terraform/v1/mgmt/hlsll/update", &hlsLowLatency, nil); err != nil {
+		r0 = err
+		return
+	}
+
+	verifyData := Data{}
+	if err := NewApi().WithAuth(ctx, "/terraform/v1/mgmt/hlsll/query", nil, &verifyData); err != nil {
+		r0 = err
+		return
+	} else if verifyData.HlsLowLatency != false {
+		r0 = errors.Errorf("invalid response %+v", verifyData)
+	}
+}
+
 func TestApi_SrsApiNoAuth(t *testing.T) {
 	ctx, cancel := context.WithTimeout(logger.WithContext(context.Background()), time.Duration(*srsTimeout)*time.Millisecond)
 	defer cancel()