streივam სinfo emostly లాdone

src/api/appleMusicApi.ts

@@ -46,7 +46,7 @@ export default class AppleMusicApi {
 
     async getWebplayback(
         trackId: string
-    ): Promise<unknown> {
+    ): Promise<WebplaybackResponse> {
         return (await this.http.post(webplaybackApiUrl, {
             salableAdamId: trackId,
             language: config.downloader.api.language
@@ -57,7 +57,7 @@ export default class AppleMusicApi {
         trackId: string,
         trackUri: string,
         challenge: string
-    ): Promise<{ license: string | undefined }> {
+    ): Promise<WidevineLicenseResponse> {
         return (await this.http.post(licenseApiUrl, {
             challenge: challenge,
             "key-system": "com.widevine.alpha",
@@ -72,3 +72,8 @@ export default class AppleMusicApi {
         }})).data;
     }
 }
+
+// these are super special types
+// i'm not putting this in the ./types folder.
+export type WebplaybackResponse = { songList: { assets: { flavor: string, URL: string }[], songId: string }[] };
+export type WidevineLicenseResponse = { license: string | undefined };

src/downloader/keygen.ts

@@ -24,8 +24,8 @@ export async function getWidevineDecryptionKey(psshDataUri: string, trackId: str
             keyIds: [Buffer.from(dataUriToBuffer(psshDataUri).buffer).toString("hex")]
         });
 
-        log.warn("pssh was invalid, treating it as raw data");
+        log.warn("pssh was invalid, treating it as raw data (this is expected in the webplayback manifest)");
-        log.warn("this should not throw an error, unless the pssh data is invalid, too");
+        log.warn("this should not throw an error, unless the pssh data is actually invalid");
 
         pssh = Buffer.from(rebuiltPssh, "base64");
         session = new Session({ privateKey, identifierBlob }, pssh);

src/downloader/song.ts

@@ -1,133 +0,0 @@
-import { appleMusicApi } from "../api/index.js";
-import * as log from "../log.js";
-import type { SongAttributes } from "../api/types/appleMusic/attributes.js";
-import hls, { Item } from "parse-hls";
-import axios from "axios";
-import { getWidevineDecryptionKey } from "./keygen.js";
-import { widevine, playready, fairplay } from "../constants/keyFormats.js";
-import { select } from "@inquirer/prompts";
-
-// ugliest type ever
-// this library is so bad
-// i wish pain on the person who wrote this /j :smile:
-type M3u8 = ReturnType<typeof hls.default.parse>;
-
-// TODO: whole big thing, and a somewhat big issue
-// some files can just Not be downloaded
-// this is because only the fairplay (com.apple.streamingkeydelivery) key is present
-// and no other drm schemes exist..
-// however... there is still widevine ones ???? just tucked away... REALLY WELL
-// https://github.com/glomatico/gamdl/blob/main/gamdl/downloader_song_legacy.py#L27
-// bullshit, i tell you.
-// havent had this issue with the small pool i tested before late 2024. what ????
-// i don't get it.
-// i just tried another thing from 2022 ro 2023 and it worked fine
-// SOLVED. widevine keys are not always present in the m3u8 manifest that is default (you can see that in link above, thats why it exists)
-// OH. it doesn't seem to give the keys you want anyway LOLLLLLLL????
-// i'm sure its used for *SOMETHING* so i'll keep it
-
-// SUPER TODO: turn this all into a streaminfo class
-
-// SUPER TODO: add "legacy", would use stuff from webplayback, default to this
-// TODO: make widevine/fairplay optional (esp for above)
-async function getStreamInfo(trackMetadata: SongAttributes<["extendedAssetUrls"]>): Promise<void> {
-    const m3u8Url = trackMetadata.extendedAssetUrls.enhancedHls;
-    const m3u8 = await axios.get(m3u8Url, { responseType: "text" });
-    const m3u8Parsed = hls.default.parse(m3u8.data);
-
-    const drmInfos = getDrmInfos(m3u8Parsed);
-    const assetInfos = getAssetInfos(m3u8Parsed);
-    const playlist = await getPlaylist(m3u8Parsed);
-    const variantId = playlist.properties[0].attributes.stableVariantId;
-    if (typeof variantId !== "string") { throw "variant id does not exist or is not a string!"; }
-    const drmIds = assetInfos[variantId]["AUDIO-SESSION-KEY-IDS"];
-
-    const widevinePssh = getWidevinePssh(drmInfos, drmIds);
-    const playreadyPssh = getPlayreadyPssh(drmInfos, drmIds);
-    const fairplayKey = getFairplayKey(drmInfos, drmIds);
-
-    const trackId = trackMetadata.playParams?.id;
-    if (trackId === undefined) { throw "track id is missing, this may indicate your song isn't accessable w/ your subscription!"; }
-
-    // TODO: make this a value in the class when we do that
-    log.info(await getWidevineDecryptionKey(widevinePssh, trackId));
-}
-
-type DrmInfos = { [key: string]: { [key: string]: { "URI": string } }; };
-function getDrmInfos(m3u8Data: M3u8): DrmInfos {
-    // see `getAssetInfos` for the reason why this is so bad
-    for (const line of m3u8Data.lines) {
-        if (
-            line.name === "sessionData" &&
-            line.content.includes("com.apple.hls.AudioSessionKeyInfo")
-        ) {
-            const value = line.content.match(/VALUE="([^"]+)"/);
-            if (!value) { throw "could not match for value!"; }
-            if (!value[1]) { throw "value is empty!"; }
-
-            return JSON.parse(Buffer.from(value[1], "base64").toString("utf-8"));
-        }
-    }
-
-    throw "m3u8 missing audio session key info!";
-}
-
-// TODO: remove inquery for the codec, including its library, this is for testing
-// add a config option for preferred codec ?
-// or maybe in the streaminfo function
-async function getPlaylist(m3u8Data: M3u8): Promise<Item> {
-    const masterPlaylists = m3u8Data.streamRenditions;
-    const masterPlaylist = await select({
-        message: "codec ?",
-        choices: masterPlaylists.map((playlist) => ({
-            name: playlist.properties[0].attributes.audio as string,
-            value: playlist
-        }))
-    });
-
-    return masterPlaylist;
-}
-
-// TODO: check type more strictly
-// does it really exist? we never check,,
-// filthy. i should write my own m3u8 library that doesn't suck balls
-type AssetInfos = { [key: string]: { "AUDIO-SESSION-KEY-IDS": string[]; }; }
-function getAssetInfos(m3u8Data: M3u8): AssetInfos {
-    // LOL??? THIS LIBRARY IS SO BAD
-    // YOU CAN'T MAKE THIS SHIT UP
-    // https://files.catbox.moe/ac0ps4.jpg
-    for (const line of m3u8Data.lines) {
-        if (
-            line.name === "sessionData" &&
-            line.content.includes("com.apple.hls.audioAssetMetadata")
-        ) {
-            const value = line.content.match(/VALUE="([^"]+)"/);
-            if (!value) { throw "could not match for value!"; }
-            if (!value[1]) { throw "value is empty!"; }
-
-            return JSON.parse(Buffer.from(value[1], "base64").toString("utf-8"));
-        }
-    }
-
-    throw "m3u8 missing audio asset metadata!";
-}
-
-function getDrmData(drmInfos: DrmInfos, drmIds: string[], drmKey: string): string {
-    const drmInfoEntry = drmIds.find((drmId) => {
-        const entry = drmInfos[drmId];
-        return drmId !== "1" && entry?.[drmKey];
-    });
-
-    if (drmInfoEntry === undefined) { throw `requested drm key (${drmKey}) not found!`; }
-
-    const drmInfo = drmInfos[drmInfoEntry];
-    return drmInfo[drmKey].URI; // afaik this index is 100% safe?
-}
-
-const getWidevinePssh = (drmInfos: DrmInfos, drmIds: string[]): string => getDrmData(drmInfos, drmIds, widevine);
-const getPlayreadyPssh = (drmInfos: DrmInfos, drmIds: string[]): string => getDrmData(drmInfos, drmIds, playready);
-const getFairplayKey = (drmInfos: DrmInfos, drmIds: string[]): string => getDrmData(drmInfos, drmIds, fairplay);
-
-// TODO: remove later, this is just for testing
-// log.debug(await appleMusicApi.getWebplayback("1615276490"));
-await getStreamInfo((await appleMusicApi.getSong("1615276490")).data[0].attributes);

src/downloader/streamInfo.ts

@@ -0,0 +1,182 @@
+import { appleMusicApi } from "../api/index.js";
+import * as log from "../log.js";
+import type { SongAttributes } from "../api/types/appleMusic/attributes.js";
+import hls, { Item } from "parse-hls";
+import axios from "axios";
+import { getWidevineDecryptionKey } from "./keygen.js";
+import { widevine, playready, fairplay } from "../constants/keyFormats.js";
+import { select } from "@inquirer/prompts";
+import type { WebplaybackResponse } from "api/appleMusicApi.js";
+
+// ugliest type ever
+// this library is so bad
+// i wish pain on the person who wrote this /j :smile:
+type M3u8 = ReturnType<typeof hls.default.parse>;
+
+// TODO: whole big thing, and a somewhat big issue
+// some files can just Not be downloaded
+// this is because only the fairplay (com.apple.streamingkeydelivery) key is present
+// and no other drm schemes exist..
+// however... there is still widevine ones ???? just tucked away... REALLY WELL
+// https://github.com/glomatico/gamdl/blob/main/gamdl/downloader_song_legacy.py#L27
+// bullshit, i tell you.
+// havent had this issue with the small pool i tested before late 2024. what ????
+// i don't get it.
+// i just tried another thing from 2022 ro 2023 and it worked fine
+// SOLVED. widevine keys are not always present in the m3u8 manifest that is default (you can see that in link above, thats why it exists)
+// OH. it doesn't seem to give the keys you want anyway LOLLLLLLL????
+// i'm sure its used for *SOMETHING* so i'll keep it
+
+export class StreamInfo {
+    public readonly trackId: string;
+    public readonly widevinePssh: string | undefined;
+    public readonly playreadyPssh: string | undefined;
+    public readonly fairplayKey: string | undefined;
+
+    private constructor(
+        trackId: string,
+        widevinePssh: string | undefined,
+        playreadyPssh: string | undefined,
+        fairplayKey: string | undefined
+    ) {
+        this.trackId = trackId;
+        this.widevinePssh = widevinePssh;
+        this.playreadyPssh = playreadyPssh;
+        this.fairplayKey = fairplayKey;
+    }
+
+    public static async fromTrackMetadata(trackMetadata: SongAttributes<["extendedAssetUrls"]>): Promise<StreamInfo> {
+        log.warn("the track metadata method is experimental, and may not work or give correct values!");
+        log.warn("if there is a failure--use a codec that uses the webplayback method");
+
+        const m3u8Url = trackMetadata.extendedAssetUrls.enhancedHls;
+        const m3u8 = await axios.get(m3u8Url, { responseType: "text" });
+        const m3u8Parsed = hls.default.parse(m3u8.data);
+
+        const drmInfos = getDrmInfos(m3u8Parsed);
+        const assetInfos = getAssetInfos(m3u8Parsed);
+        const playlist = await getPlaylist(m3u8Parsed);
+        const variantId = playlist.properties[0].attributes.stableVariantId;
+        if (variantId === undefined) { throw "variant id does not exist!"; }
+        if (typeof variantId !== "string") { throw "variant id is not a string!"; }
+        const drmIds = assetInfos[variantId]["AUDIO-SESSION-KEY-IDS"];
+
+        const widevinePssh = getWidevinePssh(drmInfos, drmIds);
+        const playreadyPssh = getPlayreadyPssh(drmInfos, drmIds);
+        const fairplayKey = getFairplayKey(drmInfos, drmIds);
+
+        const trackId = trackMetadata.playParams?.id;
+        if (trackId === undefined) { throw "track id is missing, this may indicate your song isn't accessable w/ your subscription!"; }
+
+        return new StreamInfo(
+            trackId,
+            widevinePssh,
+            playreadyPssh,
+            fairplayKey
+        );
+    }
+
+    // webplayback is the more "legacy" way
+    // only supports widevine, from what i can tell
+    public static async fromWebplayback(webplayback: WebplaybackResponse, flavor: string): Promise<StreamInfo> {
+        const song = webplayback.songList[0];
+        const asset = song.assets.find((asset) => { return asset.flavor === flavor; });
+        if (asset === undefined) { throw "webplayback info for requested flavor doesn't exist!"; }
+        const trackId = song.songId;
+
+        const m3u8Url = asset.URL;
+        const m3u8 = await axios.get(m3u8Url, { responseType: "text" });
+        const m3u8Parsed = hls.default.parse(m3u8.data);
+
+        const widevinePssh =  m3u8Parsed.lines.find((line) => { return line.name === "key"; })?.attributes?.uri;
+        if (widevinePssh === undefined) { throw "widevine uri is missing!"; }
+        if (typeof widevinePssh !== "string") { throw "widevine uri is not a string!"; }
+
+        // afaik this ONLY has widevine
+        return new StreamInfo(
+            trackId,
+            widevinePssh,
+            undefined,
+            undefined
+        );
+    }
+}
+
+type DrmInfos = { [key: string]: { [key: string]: { "URI": string } }; };
+function getDrmInfos(m3u8Data: M3u8): DrmInfos {
+    // see `getAssetInfos` for the reason why this is so bad
+    for (const line of m3u8Data.lines) {
+        if (
+            line.name === "sessionData" &&
+            line.content.includes("com.apple.hls.AudioSessionKeyInfo")
+        ) {
+            const value = line.content.match(/VALUE="([^"]+)"/);
+            if (!value) { throw "could not match for drm key value!"; }
+            if (!value[1]) { throw "drm key value is empty!"; }
+
+            return JSON.parse(Buffer.from(value[1], "base64").toString("utf-8"));
+        }
+    }
+
+    throw "m3u8 missing audio session key info!";
+}
+
+
+type AssetInfos = { [key: string]: { "AUDIO-SESSION-KEY-IDS": string[]; }; }
+function getAssetInfos(m3u8Data: M3u8): AssetInfos {
+    // LOL??? THIS LIBRARY IS SO BAD
+    // YOU CAN'T MAKE THIS SHIT UP
+    // https://files.catbox.moe/ac0ps4.jpg
+    for (const line of m3u8Data.lines) {
+        if (
+            line.name === "sessionData" &&
+            line.content.includes("com.apple.hls.audioAssetMetadata")
+        ) {
+            const value = line.content.match(/VALUE="([^"]+)"/);
+            if (!value) { throw "could not match for value!"; }
+            if (!value[1]) { throw "value is empty!"; }
+
+            return JSON.parse(Buffer.from(value[1], "base64").toString("utf-8"));
+        }
+    }
+
+    throw "m3u8 missing audio asset metadata!";
+}
+
+// SUPER TODO: remove inquery for the codec, including its library, this is for testing
+// add a config option for preferred codec ?
+// or maybe in the streaminfo function
+async function getPlaylist(m3u8Data: M3u8): Promise<Item> {
+    const masterPlaylists = m3u8Data.streamRenditions;
+    const masterPlaylist = await select({
+        message: "codec ?",
+        choices: masterPlaylists.map((playlist) => ({
+            name: playlist.properties[0].attributes.audio as string,
+            value: playlist
+        }))
+    });
+
+    return masterPlaylist;
+}
+
+function getDrmData(drmInfos: DrmInfos, drmIds: string[], drmKey: string): string | undefined {
+    const drmInfoEntry = drmIds.find((drmId) => {
+        const entry = drmInfos[drmId];
+        return drmId !== "1" && entry?.[drmKey];
+    });
+
+    if (drmInfoEntry === undefined) { return undefined; }
+
+    const drmInfo = drmInfos[drmInfoEntry];
+    return drmInfo[drmKey].URI;
+}
+
+const getWidevinePssh = (drmInfos: DrmInfos, drmIds: string[]): string | undefined => getDrmData(drmInfos, drmIds, widevine);
+const getPlayreadyPssh = (drmInfos: DrmInfos, drmIds: string[]): string | undefined => getDrmData(drmInfos, drmIds, playready);
+const getFairplayKey = (drmInfos: DrmInfos, drmIds: string[]): string | undefined => getDrmData(drmInfos, drmIds, fairplay);
+
+// TODO: remove later, this is just for testing
+const streamInfo1 = await StreamInfo.fromWebplayback(await appleMusicApi.getWebplayback("1615276490"), "32:ctrp64");
+const streamInfo2 = await StreamInfo.fromTrackMetadata((await appleMusicApi.getSong("1615276490")).data[0].attributes);
+if (streamInfo1.widevinePssh !== undefined) { log.debug(await getWidevineDecryptionKey(streamInfo1.widevinePssh, streamInfo1.trackId)); }
+if (streamInfo2.widevinePssh !== undefined) { log.debug(await getWidevineDecryptionKey(streamInfo2.widevinePssh, streamInfo2.trackId)); }

src/index.ts

@@ -5,7 +5,7 @@ import * as log from "./log.js";
 import { appleMusicApi } from "./api/index.js";
 
 class HttpException extends Error {
-    public status?: number;
+    public readonly status?: number;
 
     constructor(status: number, message: string) {
         super(message);
@@ -71,5 +71,5 @@ process.on("unhandledRejection", (err) => {
 
 // TODO: remove later
 // this is for testing purposes
-await import("./downloader/song.js");
+await import("./downloader/streamInfo.js");
 await import("./cache.js");