Merge pull request #174 from Dash-Industry-Forum/patch

MPD Patch support

.vscode/settings.json

@@ -17,9 +17,11 @@
         "gots"
     ],
     "cSpell.words": [
+        "apos",
         "Atof",
         "autodetected",
         "autoplay",
+        "beevik",
         "caddyserver",
         "cbcs",
         "cenc",
@@ -39,6 +41,7 @@
         "emsg",
         "enca",
         "encv",
+        "etree",
         "Eyevinn",
         "genurl",
         "golangci",

.wwhrd.yml

@@ -3,6 +3,7 @@ denylist:
 allowlist:
   - Apache-2.0
   - MIT
+  - BSD-2-Clause
   - BSD-3-Clause
   - CC0-1.0
 

CHANGELOG.md

@@ -7,6 +7,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- MPD Patch functionality with new `/patch_ttl` URL configuration
+- nowDate query parameter as an alternative to nowMS for MPD and patch
+
 ### Fixed
 
 - Timed stpp subtitles EBU-TT-D linePadding

cmd/livesim2/app/configurl.go

@@ -101,6 +101,7 @@ type ResponseConfig struct {
 	TimeSubsDurMS                int               `json:"TimeSubsDurMS,omitempty"`
 	TimeSubsRegion               int               `json:"TimeSubsRegion,omitempty"`
 	Host                         string            `json:"Host,omitempty"`
+	PatchTTL                     int               `json:"Patch,omitempty"`
 	// DashIFECCP is DASH-IF Enhanced Clear Key Content Protection
 	DashIFECCP     string           `json:"ECCP,omitempty"`
 	SegStatusCodes []SegStatusCodes `json:"SegStatus,omitempty"`
@@ -375,6 +376,11 @@ cfgLoop:
 			cfg.Traffic = sc.ParseLossItvls(key, val)
 		case "eccp":
 			cfg.DashIFECCP = val
+		case "patch":
+			ttl := sc.Atoi(key, val)
+			if ttl > 0 {
+				cfg.PatchTTL = ttl
+			}
 		default:
 			contentStartIdx = i
 			break cfgLoop

cmd/livesim2/app/handler_livesim.go

@@ -38,17 +38,29 @@ func (s *Server) livesimHandlerFunc(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	var nowMS int // Set from query string or from wall-clock
 	q := r.URL.Query()
-	nowMSValue := q.Get("nowMS")
-	if nowMSValue != "" {
-		nowMS, err = strconv.Atoi(nowMSValue)
+	nowMS, err := getNowMS(q.Get("nowMS"))
+	if err != nil {
+		http.Error(w, "bad nowMS query", http.StatusBadRequest)
+		return
+	}
+
+	nowDate := q.Get("nowDate")
+	if nowDate != "" {
+		nowMS, err = getMSFromDate(nowDate)
+		if err != nil {
+			http.Error(w, "bad date query", http.StatusBadRequest)
+			return
+		}
+	}
+
+	publishTime := q.Get("publishTime")
+	if publishTime != "" {
+		nowMS, err = getMSFromDate(publishTime)
 		if err != nil {
-			http.Error(w, "bad nowMS query", http.StatusBadRequest)
+			http.Error(w, "bad publishTime query", http.StatusBadRequest)
 			return
 		}
-	} else {
-		nowMS = int(time.Now().UnixMilli())
 	}
 
 	cfg, err := processURLCfg(u.String(), nowMS)
@@ -144,6 +156,25 @@ func (s *Server) livesimHandlerFunc(w http.ResponseWriter, r *http.Request) {
 	}
 }
 
+// getNowMS returns value from query or local clock.
+func getNowMS(nowMSValue string) (nowMS int, err error) {
+	if nowMSValue != "" {
+		return strconv.Atoi(nowMSValue)
+	}
+	return int(time.Now().UnixMilli()), nil
+}
+
+// getMSFromDate returns a nowMS value based on date (+1ms).
+// The extra millisecond is there to ensure that the corresponding manifest
+// can be generated
+func getMSFromDate(publishTimeValue string) (nowMS int, err error) {
+	t, err := time.Parse(time.RFC3339, publishTimeValue)
+	if err != nil {
+		return -1, err
+	}
+	return int(t.UnixMilli()) + 1, nil
+}
+
 // extractPattern extracts the pattern number and return a modified segmentPart.
 func extractPattern(segmentPart string) (int, string) {
 	parts := strings.Split(segmentPart, "/")

cmd/livesim2/app/handler_livesim_test.go

@@ -74,6 +74,18 @@ func TestParamToMPD(t *testing.T) {
 				`<dashif:Laurl xmlns:dashif="https://dashif.org/CPS" licenseType="EME-1.0">`,
 			},
 		},
+		{
+			desc:             "MPD with Patch",
+			mpd:              "testpic_6s/Manifest.mpd",
+			params:           "patch_60/",
+			wantedStatusCode: http.StatusOK,
+			wantedInMPD: []string{
+				`id="auto-patch-id"`, // id in MPD
+				`id="1"`,             // id in AdaptationSet
+				`id="2"`,             // id in AdaptationSet
+				`<PatchLocation ttl="60">/patch/livesim2/patch_60/testpic_6s/Manifest.mpp?publishTime=`, // PatchLocation
+			},
+		},
 	}
 
 	for _, tc := range testCases {

cmd/livesim2/app/handler_patch.go

@@ -0,0 +1,97 @@
+package app
+
+import (
+	"errors"
+	"log/slog"
+	"net/http"
+	"strconv"
+	"strings"
+
+	"github.com/Dash-Industry-Forum/livesim2/pkg/patch"
+)
+
+type rec struct {
+	body   []byte
+	status int
+}
+
+func (r *rec) Write(b []byte) (int, error) {
+	r.body = append(r.body, b...)
+	return len(b), nil
+}
+
+func (r *rec) WriteHeader(status int) {
+	r.status = status
+}
+
+func (r *rec) Header() http.Header {
+	return http.Header{}
+}
+
+// patchHandlerFunc returns an MPD patch
+func (s *Server) patchHandlerFunc(w http.ResponseWriter, r *http.Request) {
+	origQuery := r.URL.RawQuery
+	q := r.URL.Query()
+	publishTime := q.Get("publishTime")
+	if publishTime == "" {
+		slog.Warn("publishTime query is required, but not provided in patch request")
+		http.Error(w, "publishTime query is required", http.StatusBadRequest)
+	}
+	old := &rec{}
+	oldQuery := removeQuery(origQuery, "nowMS")
+	oldQuery = removeQuery(oldQuery, "nowDate")
+	mpdPath := mpdPathFromPatchPath(r.URL.Path)
+	r.URL.Path = mpdPath
+	r.URL.RawQuery = oldQuery
+	s.livesimHandlerFunc(old, r)
+
+	new := &rec{}
+	newQuery := removeQuery(origQuery, "publishTime")
+	r.URL.RawQuery = newQuery
+	s.livesimHandlerFunc(new, r)
+
+	doc, err := patch.MPDDiff(old.body, new.body)
+	switch {
+	case errors.Is(err, patch.ErrPatchSamePublishTime):
+		http.Error(w, err.Error(), http.StatusTooEarly)
+		return
+	case errors.Is(err, patch.ErrPatchTooLate):
+		http.Error(w, err.Error(), http.StatusGone)
+		return
+	case err != nil:
+		slog.Error("MPDDiff", "err", err)
+		http.Error(w, "MPDDiff", http.StatusInternalServerError)
+		return
+	}
+	doc.Indent(2)
+	b, err := doc.WriteToBytes()
+	if err != nil {
+		slog.Error("WriteToBytes", "err", err)
+		http.Error(w, "WriteToBytes", http.StatusInternalServerError)
+		return
+	}
+	w.Header().Set("Content-Type", "application/dash-patch+xml")
+	w.Header().Set("Content-Length", strconv.Itoa(len(b)))
+	_, err = w.Write(b)
+	if err != nil {
+		slog.Error("Write", "err", err)
+	}
+	w.WriteHeader(http.StatusOK)
+}
+
+func mpdPathFromPatchPath(patchPath string) string {
+	mpdPath := strings.Replace(patchPath, ".mpp", ".mpd", 1)
+	//TODO. Handle a possible set prefix before patch
+	return strings.TrimPrefix(mpdPath, "/patch")
+}
+
+func removeQuery(query, key string) string {
+	q := strings.Split(query, "&")
+	for i, kv := range q {
+		if strings.HasPrefix(kv, key+"=") {
+			q = append(q[:i], q[i+1:]...)
+			break
+		}
+	}
+	return strings.Join(q, "&")
+}

cmd/livesim2/app/handler_patch_test.go

@@ -0,0 +1,113 @@
+package app
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/Dash-Industry-Forum/livesim2/pkg/logging"
+	"github.com/stretchr/testify/require"
+)
+
+var wantedPatchSegTimelineTime = `<?xml version="1.0" encoding="UTF-8"?>
+<Patch xmlns="urn:mpeg:dash:schema:mpd-patch:2020" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="urn:mpeg:dash:schema:mpd-patch:2020 DASH-MPD-PATCH.xsd" mpdId="base" originalPublishTime="2024-04-02T15:50:56Z" publishTime="2024-04-02T15:52:40Z">
+  <replace sel="/MPD/@publishTime">2024-04-02T15:52:40Z</replace>
+  <replace sel="/MPD/PatchLocation[1]">
+    <PatchLocation ttl="60">/patch/livesim2/patch_60/segtimeline_1/testpic_2s/Manifest.mpp?publishTime=2024-04-02T15%3A52%3A40Z</PatchLocation>
+  </replace>
+  <remove sel="/MPD/Period[@id=&apos;P0&apos;]/AdaptationSet[@id=&apos;1&apos;]/SegmentTemplate/SegmentTimeline/S[1]"/>
+  <add sel="/MPD/Period[@id=&apos;P0&apos;]/AdaptationSet[@id=&apos;1&apos;]/SegmentTemplate/SegmentTimeline" pos="prepend">
+    <S t="82179508704256" d="96256" r="1"/>
+  </add>
+  <remove sel="/MPD/Period[@id=&apos;P0&apos;]/AdaptationSet[@id=&apos;2&apos;]/SegmentTemplate/SegmentTimeline/S[1]"/>
+  <add sel="/MPD/Period[@id=&apos;P0&apos;]/AdaptationSet[@id=&apos;2&apos;]/SegmentTemplate/SegmentTimeline" pos="prepend">
+    <S t="154086578820000" d="180000" r="30"/>
+  </add>
+</Patch>
+`
+
+var wantedPatchSegTimelineNumberWithAddAtEnd = `<?xml version="1.0" encoding="UTF-8"?>
+<Patch xmlns="urn:mpeg:dash:schema:mpd-patch:2020" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="urn:mpeg:dash:schema:mpd-patch:2020 DASH-MPD-PATCH.xsd" mpdId="base" originalPublishTime="2024-04-16T07:34:38Z" publishTime="2024-04-16T07:34:56Z">
+  <replace sel="/MPD/@publishTime">2024-04-16T07:34:56Z</replace>
+  <replace sel="/MPD/PatchLocation[1]">
+    <PatchLocation ttl="60">/patch/livesim2/patch_60/segtimelinenr_1/testpic_2s/Manifest.mpp?publishTime=2024-04-16T07%3A34%3A56Z</PatchLocation>
+  </replace>
+  <replace sel="/MPD/Period[@id=&apos;P0&apos;]/AdaptationSet[@id=&apos;1&apos;]/SegmentTemplate/@startNumber">856626417</replace>
+  <remove sel="/MPD/Period[@id=&apos;P0&apos;]/AdaptationSet[@id=&apos;1&apos;]/SegmentTemplate/SegmentTimeline/S[1]"/>
+  <add sel="/MPD/Period[@id=&apos;P0&apos;]/AdaptationSet[@id=&apos;1&apos;]/SegmentTemplate/SegmentTimeline" pos="prepend">
+    <S t="82236136032256" d="96256" r="1"/>
+  </add>
+  <add sel="/MPD/Period[@id=&apos;P0&apos;]/AdaptationSet[@id=&apos;1&apos;]/SegmentTemplate/SegmentTimeline/S[15]" pos="after">
+    <S d="95232"/>
+  </add>
+  <replace sel="/MPD/Period[@id=&apos;P0&apos;]/AdaptationSet[@id=&apos;2&apos;]/SegmentTemplate/@startNumber">856626417</replace>
+  <remove sel="/MPD/Period[@id=&apos;P0&apos;]/AdaptationSet[@id=&apos;2&apos;]/SegmentTemplate/SegmentTimeline/S[1]"/>
+  <add sel="/MPD/Period[@id=&apos;P0&apos;]/AdaptationSet[@id=&apos;2&apos;]/SegmentTemplate/SegmentTimeline" pos="prepend">
+    <S t="154192755060000" d="180000" r="30"/>
+  </add>
+</Patch>
+`
+
+func TestPatchHandler(t *testing.T) {
+	cfg := ServerConfig{
+		VodRoot:   "testdata/assets",
+		TimeoutS:  0,
+		LogFormat: logging.LogDiscard,
+	}
+	err := logging.InitSlog(cfg.LogLevel, cfg.LogFormat)
+	require.NoError(t, err)
+	server, err := SetupServer(context.Background(), &cfg)
+	require.NoError(t, err)
+	ts := httptest.NewServer(server.Router)
+	defer ts.Close()
+	testCases := []struct {
+		desc              string
+		url               string
+		wantedStatusCode  int
+		wantedContentType string
+		wantedBody        string
+	}{
+		{
+			desc:              "segTimeline no update yet",
+			url:               "/patch/livesim2/patch_60/segtimeline_1/testpic_2s/Manifest.mpp?publishTime=2024-04-16T07:34:38Z&nowDate=2024-04-16T07:34:39Z",
+			wantedStatusCode:  http.StatusTooEarly,
+			wantedContentType: "text/plain; charset=utf-8",
+			wantedBody:        "",
+		},
+		{
+			desc:              "segTimeline too late",
+			url:               "/patch/livesim2/patch_60/segtimeline_1/testpic_2s/Manifest.mpp?publishTime=2024-04-16T07:34:38Z&nowDate=2024-04-16T07:44:39Z",
+			wantedStatusCode:  http.StatusGone,
+			wantedContentType: "text/plain; charset=utf-8",
+			wantedBody:        "",
+		},
+		{
+			desc:              "segTimeline",
+			url:               "/patch/livesim2/patch_60/segtimeline_1/testpic_2s/Manifest.mpp?publishTime=2024-04-02T15:50:56Z&nowMS=1712073160000",
+			wantedStatusCode:  http.StatusOK,
+			wantedContentType: "application/dash-patch+xml",
+			wantedBody:        wantedPatchSegTimelineTime,
+		},
+		{
+			desc:              "segTimeline with Number",
+			url:               "/patch/livesim2/patch_60/segtimelinenr_1/testpic_2s/Manifest.mpp?publishTime=2024-04-16T07:34:38Z&nowDate=2024-04-16T07:34:57Z",
+			wantedStatusCode:  http.StatusOK,
+			wantedContentType: "application/dash-patch+xml",
+			wantedBody:        wantedPatchSegTimelineNumberWithAddAtEnd,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.desc, func(t *testing.T) {
+			resp, body := testFullRequest(t, ts, "GET", tc.url, nil)
+			require.Equal(t, tc.wantedStatusCode, resp.StatusCode)
+			require.Equal(t, tc.wantedContentType, resp.Header.Get("Content-Type"))
+			if tc.wantedStatusCode != http.StatusOK {
+				return
+			}
+			bodyStr := string(body)
+			require.Equal(t, tc.wantedBody, bodyStr)
+		})
+	}
+}

cmd/livesim2/app/handler_urlgen.go

@@ -122,6 +122,7 @@ type urlGenData struct {
 	StartRel                    string   // sets timeline start (and availabilityStartTime) relative to now (in seconds). Normally negative value.
 	StopRel                     string   // sets stop-time for time-limited event relative to now (in seconds)
 	Scte35Var                   string   // SCTE-35 insertion variant
+	PatchTTL                    string   // MPD Patch TTL  inv value in seconds (> 0 to be valid))
 	StatusCodes                 string   // comma-separated list of response code patterns to return
 	Traffic                     string   // comma-separated list of up/down/slow/hang intervals for one or more BaseURLs in MPD
 	Errors                      []string // error messages to display due to bad configuration
@@ -273,6 +274,16 @@ func createURL(r *http.Request, aInfo assetsInfo) urlGenData {
 			sb.WriteString(fmt.Sprintf("ltgt_%d/", lt))
 		}
 	}
+	if ptl := q.Get("patch-ttl"); ptl != "" {
+		patchTTL, err := strconv.Atoi(ptl)
+		if err != nil {
+			panic("bad patch-ttl")
+		}
+		if patchTTL > 0 {
+			data.PatchTTL = ptl
+			sb.WriteString(fmt.Sprintf("patch_%s/", ptl))
+		}
+	}
 	start := q.Get("start")
 	if start != "" {
 		data.Start = start