initTime remove

superstreamerapp · Nov 14, 2024 · 0a3655d · 0a3655d
1 parent 0af1ac9
commit 0a3655d
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Showing 5 changed files with 50 additions and 35 deletions.
diff --git a/packages/stitcher/src/interstitials.ts b/packages/stitcher/src/interstitials.ts
@@ -1,4 +1,5 @@
 import { DateTime } from "luxon";
+import { assert } from "shared/assert";
 import { env } from "./env";
 import { resolveUri, toAssetProtocol } from "./lib/url";
 import { fetchMasterPlaylistDuration } from "./playlist";
@@ -22,18 +23,20 @@ interface InterstitialAsset {
 }
 
 export function getStaticDateRanges(session: Session) {
+  assert(session.startTime, "No startTime in session");
+
   const group: Record<string, InterstitialType[]> = {};
 
   if (session.vmapResponse) {
     for (const adBreak of session.vmapResponse.adBreaks) {
-      const dateTime = session.initTime.plus({ seconds: adBreak.timeOffset });
+      const dateTime = session.startTime.plus({ seconds: adBreak.timeOffset });
       groupTimeOffset(group, dateTime, "ad");
     }
   }
 
   if (session.interstitials) {
     for (const interstitial of session.interstitials) {
-      const dateTime = session.initTime.plus({
+      const dateTime = session.startTime.plus({
         seconds: interstitial.timeOffset,
       });
       groupTimeOffset(group, dateTime, interstitial.type);
@@ -80,13 +83,15 @@ function groupTimeOffset(
 }
 
 export async function getAssets(session: Session, lookupDate: DateTime) {
+  assert(session.startTime, "No startTime in session");
+
   const assets: InterstitialAsset[] = [];
 
   if (session.vmapResponse) {
     await formatStaticAdBreaks(
       assets,
       session.vmapResponse,
-      session.initTime,
+      session.startTime,
       lookupDate,
     );
   }
@@ -95,7 +100,7 @@ export async function getAssets(session: Session, lookupDate: DateTime) {
     await formatStaticInterstitials(
       assets,
       session.interstitials,
-      session.initTime,
+      session.startTime,
       lookupDate,
     );
   }

diff --git a/packages/stitcher/src/lib/url.ts b/packages/stitcher/src/lib/url.ts
@@ -1,6 +1,7 @@
 import * as path from "path";
 import { env } from "../env";
 import type { Filter } from "../filters";
+import type { Session } from "../session";
 
 const uuidRegex = /^[a-z,0-9,-]{36,36}$/;
 
@@ -69,13 +70,13 @@ export function buildProxyUrl(
   url: string,
   params?: {
     filter?: Filter;
-    sessionId?: string;
+    session?: Session;
     params?: Record<string, string>;
   },
 ) {
   return buildUrl(`${env.PUBLIC_STITCHER_ENDPOINT}/out/${file}`, {
     url,
-    sessionId: params?.sessionId,
+    sid: params?.session?.id,
 
     // Filter query params.
     "filter.resolution": params?.filter?.resolution,

diff --git a/packages/stitcher/src/playlist.ts b/packages/stitcher/src/playlist.ts
@@ -1,4 +1,5 @@
 import { DateTime } from "luxon";
+import { assert } from "shared/assert";
 import { filterMasterPlaylist } from "./filters";
 import { getAssets, getStaticDateRanges } from "./interstitials";
 import { buildProxyUrl, joinUrl, resolveUri } from "./lib/url";
@@ -23,7 +24,7 @@ export async function formatMasterPlaylist(
 
   for (const variant of master.variants) {
     variant.uri = buildProxyUrl("playlist.m3u8", joinUrl(url, variant.uri), {
-      sessionId: session.id,
+      session,
       params: {
         type: "video",
       },
@@ -46,7 +47,7 @@ export async function formatMasterPlaylist(
       "playlist.m3u8",
       joinUrl(url, rendition.uri),
       {
-        sessionId: session.id,
+        session,
         params: {
           type,
         },
@@ -62,12 +63,15 @@ export async function formatMediaPlaylist(
   type: "video" | "audio" | "text",
   url: string,
 ) {
+  assert(session.startTime, "No startTime in session");
+
   const media = await fetchMediaPlaylist(url);
 
   if (type === "video" && media.endlist && media.segments[0]) {
     // When we have an endlist, the playlist is static. We can check whether we need
     // to add dateRanges.
-    media.segments[0].programDateTime = session.initTime;
+
+    media.segments[0].programDateTime = session.startTime;
     media.dateRanges = getStaticDateRanges(session);
   }
 

diff --git a/packages/stitcher/src/routes/session.ts b/packages/stitcher/src/routes/session.ts
@@ -16,12 +16,12 @@ export const session = new Elysia()
   .post(
     "/session",
     async ({ body }) => {
-      const sessionId = await createSession(body);
+      const session = await createSession(body);
 
       const masterUrl = resolveUri(body.uri);
 
       const url = buildProxyUrl("master.m3u8", masterUrl, {
-        sessionId,
+        session,
         filter: body.filter,
       });
 
@@ -87,9 +87,9 @@ export const session = new Elysia()
   .get(
     "/out/master.m3u8",
     async ({ set, query }) => {
-      const session = await getSession(query.sessionId);
+      const session = await getSession(query.sid);
 
-      await formatSessionByMasterRequest(query.sessionId, session);
+      await formatSessionByMasterRequest(session);
 
       const filter = extractFilterFromQuery(query);
 
@@ -105,15 +105,15 @@ export const session = new Elysia()
       },
       query: t.Object({
         url: t.String(),
-        sessionId: t.String(),
+        sid: t.String(),
         "filter.resolution": t.Optional(t.String()),
       }),
     },
   )
   .get(
     "/out/playlist.m3u8",
     async ({ set, query }) => {
-      const session = await getSession(query.sessionId);
+      const session = await getSession(query.sid);
 
       const playlist = await formatMediaPlaylist(
         session,
@@ -136,7 +136,7 @@ export const session = new Elysia()
           t.Literal("text"),
         ]),
         url: t.String(),
-        sessionId: t.String(),
+        sid: t.String(),
       }),
     },
   )

diff --git a/packages/stitcher/src/session.ts b/packages/stitcher/src/session.ts
@@ -8,7 +8,8 @@ import type { VmapResponse } from "./vmap";
 
 export interface Session {
   id: string;
-  initTime: DateTime;
+  startTime?: DateTime;
+  expiry: number;
   vmap?: {
     url: string;
   };
@@ -25,14 +26,15 @@ export async function createSession(params: {
     uri: string;
     type?: InterstitialType;
   }[];
+  expiry?: number;
 }) {
   const id = randomUUID();
 
-  const initTime = DateTime.now();
   const session: Session = {
     id,
-    initTime,
     vmap: params.vmap,
+    // A session is valid for 3 hours by default.
+    expiry: params.expiry ?? 60 * 60 * 3,
   };
 
   if (params.interstitials?.length) {
@@ -45,10 +47,11 @@ export async function createSession(params: {
     });
   }
 
-  const ttl = 3600;
-  await kv.set(`session:${id}`, serializeSession(session), ttl);
+  // We'll initially store the session for 10 minutes, if it's not been consumed
+  // within the timeframe, it's gone.
+  await kv.set(`session:${id}`, serializeSession(session), 60 * 10);
 
-  return id;
+  return session;
 }
 
 export async function getSession(id: string) {
@@ -59,30 +62,32 @@ export async function getSession(id: string) {
   return deserializeSession(id, data);
 }
 
-export async function formatSessionByMasterRequest(
-  id: string,
-  session: Session,
-) {
-  let updateSession = false;
+export async function formatSessionByMasterRequest(session: Session) {
+  // Check if we have a startTime, if so, the master playlist has been requested
+  // before and we no longer need it.
+  if (session.startTime) {
+    return;
+  }
+
+  session.startTime = DateTime.now();
 
   if (session.vmap) {
     session.vmapResponse = await fetchVmap(session.vmap.url);
     delete session.vmap;
-
-    updateSession = true;
   }
 
-  if (updateSession) {
-    const ttl = 3600;
-    await kv.set(`session:${id}`, serializeSession(session), ttl);
-  }
+  await kv.set(
+    `session:${session.id}`,
+    serializeSession(session),
+    session.expiry,
+  );
 }
 
 function serializeSession(session: Session) {
   const copy = {
     ...session,
     id: undefined,
-    initTime: session.initTime.toISO(),
+    startTime: session.startTime?.toISO(),
   };
   return JSON.stringify(copy);
 }
@@ -92,7 +97,7 @@ function deserializeSession(id: string, value: string): Session {
   const session = {
     ...copy,
     id,
-    initTime: DateTime.fromISO(copy.initTime),
+    startTime: copy.startTime ? DateTime.fromISO(copy.startTime) : undefined,
   };
   return session;
 }