Add a typescript linter.

web/.eslintrc.cjs

@@ -9,5 +9,14 @@ module.exports = {
     "@typescript-eslint/ban-ts-comment": "off",
     "@typescript-eslint/no-non-null-assertion": "off",
     "@typescript-eslint/no-explicit-any": "off",
+    "no-unused-vars": "off", // note you must disable the base rule as it can report incorrect errors
+    "@typescript-eslint/no-unused-vars": [
+      "warn", // or "error"
+      {
+        "argsIgnorePattern": "^_",
+        "varsIgnorePattern": "^_",
+        "caughtErrorsIgnorePattern": "^_"
+      }
+    ],
   }
 };

web/package.json

@@ -4,15 +4,19 @@
   "scripts": {
     "serve": "parcel serve --https --cert ../cert/localhost.crt --key ../cert/localhost.key --port 4444 --open",
     "build": "parcel build",
-    "check": "tsc --noEmit"
+    "check": "tsc --noEmit",
+	"lint": "eslint ."
   },
   "devDependencies": {
     "@parcel/transformer-inline-string": "2.8.3",
     "@parcel/validator-typescript": "^2.6.0",
     "@types/audioworklet": "^0.0.41",
     "@types/dom-webcodecs": "^0.1.6",
+    "@typescript-eslint/eslint-plugin": "^5.59.7",
+    "@typescript-eslint/parser": "^5.59.7",
+    "eslint": "^8.41.0",
     "parcel": "^2.8.0",
-    "typescript": ">=3.0.0"
+    "typescript": "^5.0.4"
   },
   "dependencies": {
     "mp4box": "^0.5.2"

web/src/broadcaster/encoder.ts

@@ -69,7 +69,7 @@ export class Encoder {
 			dts: frame.timestamp,
 		});
 
-		const stream = this.container.createSingleSampleMoof(sample);
+		const _stream = this.container.createSingleSampleMoof(sample);
 	}
 
 	onVideo(frame: EncodedVideoChunk, metadata?: EncodedVideoChunkMetadata) {
@@ -99,6 +99,6 @@ export class Encoder {
 			dts: frame.timestamp,
 		});
 
-		const stream = this.container.createSingleSampleMoof(sample);
+		const _stream = this.container.createSingleSampleMoof(sample);
 	}
 }

web/src/broadcaster/index.ts

@@ -1,4 +1,5 @@
 export default class Broadcaster {
 	constructor() {
+		// TODO
 	}
 }

web/src/index.ts

@@ -5,7 +5,7 @@ import Transport from "./transport"
 import fingerprintHex from 'bundle-text:../fingerprint.hex';
 
 // Convert the hex to binary.
-let fingerprint = [];
+const fingerprint = [];
 for (let c = 0; c < fingerprintHex.length - 1; c += 2) {
     fingerprint.push(parseInt(fingerprintHex.substring(c, c + 2), 16));
 }

web/src/mp4/init.ts

@@ -26,11 +26,11 @@ export class InitParser {
 
 	push(data: Uint8Array) {
 		// Make a copy of the atom because mp4box only accepts an ArrayBuffer unfortunately
-		let box = new Uint8Array(data.byteLength);
+		const box = new Uint8Array(data.byteLength);
 		box.set(data)
 
 		// and for some reason we need to modify the underlying ArrayBuffer with fileStart
-		let buffer = box.buffer as MP4.ArrayBuffer
+		const buffer = box.buffer as MP4.ArrayBuffer
 		buffer.fileStart = this.offset
 
 		// Parse the data

web/src/mp4/mp4box.d.ts

@@ -121,10 +121,10 @@ declare module "mp4box" {
         mapUint8Array(length: number): Uint8Array;
         readInt32Array(length: number, littleEndian: boolean): Int32Array;
         readInt16Array(length: number, littleEndian: boolean): Int16Array;
-        readInt8(length: number): Int8Array;
+        readInt8Array(length: number): Int8Array;
         readUint32Array(length: number, littleEndian: boolean): Uint32Array;
         readUint16Array(length: number, littleEndian: boolean): Uint16Array;
-        readUint8(length: number): Uint8Array;
+        readUint8Array(length: number): Uint8Array;
         readFloat64Array(length: number, littleEndian: boolean): Float64Array;
         readFloat32Array(length: number, littleEndian: boolean): Float32Array;
 

web/src/player/audio.ts

@@ -8,7 +8,7 @@ export default class Audio {
     render?: number; // non-zero if requestAnimationFrame has been called
     last?: number; // the timestamp of the last rendered frame, in microseconds
 
-    constructor(config: Message.Config) {
+    constructor(_config: Message.Config) {
         this.queue = []
     }
 
@@ -47,7 +47,7 @@ export default class Audio {
         }
 
         while (this.queue.length) {
-            let frame = this.queue[0];
+            const frame = this.queue[0];
             if (ring.size() + frame.numberOfFrames > ring.capacity) {
                 // Buffer is full
                 break

web/src/player/decoder.ts

@@ -16,8 +16,8 @@ export default class Decoder {
     }
 
     async receiveInit(msg: Message.Init) {
-        let stream = new Stream.Reader(msg.reader, msg.buffer);
-        while (1) {
+        const stream = new Stream.Reader(msg.reader, msg.buffer);
+        for (;;) {
             const data = await stream.read()
             if (!data) break
 
@@ -29,14 +29,14 @@ export default class Decoder {
 
     async receiveSegment(msg: Message.Segment) {
 		// Wait for the init segment to be fully received and parsed
-		const info = await this.init.info
+		const init = await this.init.info
 		const input = MP4.New();
 
         input.onSamples = this.onSamples.bind(this);
-		input.onReady = (info: any) => {
+		input.onReady = (track: any) => {
             // Extract all of the tracks, because we don't know if it's audio or video.
-            for (let track of info.tracks) {
-                input.setExtractionOptions(track.id, track, { nbSamples: 1 });
+            for (const i of init.tracks) {
+                input.setExtractionOptions(track.id, i, { nbSamples: 1 });
             }
 
 			input.start();
@@ -45,7 +45,7 @@ export default class Decoder {
         // MP4box requires us to reparse the init segment unfortunately
         let offset = 0;
 
-        for (let raw of this.init.raw) {
+        for (const raw of this.init.raw) {
             raw.fileStart = offset
             offset = input.appendBuffer(raw)
         }
@@ -61,11 +61,11 @@ export default class Decoder {
 			const atom = await stream.bytes(size)
 
             // Make a copy of the atom because mp4box only accepts an ArrayBuffer unfortunately
-            let box = new Uint8Array(atom.byteLength);
+            const box = new Uint8Array(atom.byteLength);
             box.set(atom)
 
             // and for some reason we need to modify the underlying ArrayBuffer with offset
-            let buffer = box.buffer as MP4.ArrayBuffer
+            const buffer = box.buffer as MP4.ArrayBuffer
             buffer.fileStart = offset
 
             // Parse the data
@@ -79,7 +79,7 @@ export default class Decoder {
 
         if (!decoder) {
             // We need a sample to initalize the video decoder, because of mp4box limitations.
-            let sample = samples[0];
+            const sample = samples[0];
 
             if (isVideoTrack(track)) {
                 // Configure the decoder using the AVC box for H.264
@@ -124,7 +124,7 @@ export default class Decoder {
             this.decoders.set(track_id, decoder)
         }
 
-        for (let sample of samples) {
+        for (const sample of samples) {
             // Convert to microseconds
             const timestamp = 1000 * 1000 * sample.dts / sample.timescale
             const duration = 1000 * 1000 * sample.duration / sample.timescale

web/src/player/index.ts

@@ -45,7 +45,7 @@ export default class Player {
         return worker
     }
 
-    private async setupWorklet(config: Config): Promise<AudioWorkletNode> {
+    private async setupWorklet(_config: Config): Promise<AudioWorkletNode> {
         // Load the worklet source code.
         const url = new URL('worklet.ts', import.meta.url)
         await this.context.audioWorklet.addModule(url)

web/src/player/ring.ts

@@ -37,7 +37,7 @@ export class Ring {
         this.state = new Int32Array(buffer.state)
 
         this.channels = []
-        for (let channel of buffer.channels) {
+        for (const channel of buffer.channels) {
             this.channels.push(new Float32Array(channel))
         }
 
@@ -46,8 +46,8 @@ export class Ring {
 
     // Write samples for single audio frame, returning the total number written.
     write(frame: AudioData): number {
-        let readPos = Atomics.load(this.state, STATE.READ_POS)
-        let writePos = Atomics.load(this.state, STATE.WRITE_POS)
+        const readPos = Atomics.load(this.state, STATE.READ_POS)
+        const writePos = Atomics.load(this.state, STATE.WRITE_POS)
 
         const startPos = writePos
         let endPos = writePos + frame.numberOfFrames;
@@ -60,8 +60,8 @@ export class Ring {
             }
         }
 
-        let startIndex = startPos % this.capacity;
-        let endIndex = endPos % this.capacity;
+        const startIndex = startPos % this.capacity;
+        const endIndex = endPos % this.capacity;
 
         // Loop over each channel
         for (let i = 0; i < this.channels.length; i += 1) {
@@ -102,10 +102,10 @@ export class Ring {
     }
 
     read(dst: Float32Array[]): number {
-        let readPos = Atomics.load(this.state, STATE.READ_POS)
-        let writePos = Atomics.load(this.state, STATE.WRITE_POS)
+        const readPos = Atomics.load(this.state, STATE.READ_POS)
+        const writePos = Atomics.load(this.state, STATE.WRITE_POS)
 
-        let startPos = readPos;
+        const startPos = readPos;
         let endPos = startPos + dst[0].length;
 
         if (endPos > writePos) {
@@ -116,8 +116,8 @@ export class Ring {
             }
         }
 
-        let startIndex = startPos % this.capacity;
-        let endIndex = endPos % this.capacity;
+        const startIndex = startPos % this.capacity;
+        const endIndex = endPos % this.capacity;
 
         // Loop over each channel
         for (let i = 0; i < dst.length; i += 1) {
@@ -147,8 +147,8 @@ export class Ring {
 
     size() {
         // TODO is this thread safe?
-        let readPos = Atomics.load(this.state, STATE.READ_POS)
-        let writePos = Atomics.load(this.state, STATE.WRITE_POS)
+        const readPos = Atomics.load(this.state, STATE.READ_POS)
+        const writePos = Atomics.load(this.state, STATE.WRITE_POS)
 
         return writePos - readPos
     }

web/src/player/video.ts

@@ -89,7 +89,7 @@ export default class Video {
         frame.close()
     }
 
-    play(play: Message.Play) {
+    play(_play: Message.Play) {
         // Queue up to render the next frame.
         if (!this.render) {
             this.render = self.requestAnimationFrame(this.draw.bind(this))

web/src/player/worklet.ts

@@ -10,7 +10,7 @@ class Renderer extends AudioWorkletProcessor {
     ring?: Ring;
     base: number;
 
-    constructor(params: AudioWorkletNodeOptions) {
+    constructor(_params: AudioWorkletNodeOptions) {
         // The super constructor call is required.
         super();
 
@@ -29,7 +29,7 @@ class Renderer extends AudioWorkletProcessor {
     }
 
     // Inputs and outputs in groups of 128 samples.
-    process(inputs: Float32Array[][], outputs: Float32Array[][], parameters: Record<string, Float32Array>): boolean {
+    process(inputs: Float32Array[][], outputs: Float32Array[][], _parameters: Record<string, Float32Array>): boolean {
         if (!this.ring) {
             // Paused
             return true

web/src/stream/reader.ts

@@ -28,7 +28,7 @@ export default class Reader {
 	async readAll(): Promise<Uint8Array> {
 		const r = this.reader.getReader()
 
-		while (1) {
+		for (;;) {
 			const result = await r.read()
 			if (result.done) {
 				break
@@ -164,18 +164,22 @@ export default class Reader {
 		const size = (first & 0xc0) >> 6
 
 		switch (size) {
-		case 0:
-			const v0 = await this.uint8()
-			return BigInt(v0) & 0x3fn
-		case 1:
-			const v1 = await this.uint16()
-			return BigInt(v1) & 0x3fffn
-		case 2:
-			const v2 = await this.uint32()
-			return BigInt(v2) & 0x3fffffffn
-		case 3:
-			const v3 = await this.uint64()
-			return v3 & 0x3fffffffffffffffn
+		case 0: {
+			const v = await this.uint8()
+			return BigInt(v) & 0x3fn
+		}
+		case 1: {
+			const v = await this.uint16()
+			return BigInt(v) & 0x3fffn
+		}
+		case 2: {
+			const v = await this.uint32()
+			return BigInt(v) & 0x3fffffffn
+		}
+		case 3: {
+			const v = await this.uint64()
+			return v & 0x3fffffffffffffffn
+		}
 		default:
 			throw "impossible"
 		}
@@ -183,7 +187,7 @@ export default class Reader {
 
 	async done(): Promise<boolean> {
 		try {
-			const peek = await this.peek(1)
+			await this.peek(1)
 			return false
 		} catch (err) {
 			return true // Assume EOF

web/src/transport/index.ts

@@ -29,7 +29,7 @@ export default class Transport {
 
 	// Helper function to make creating a promise easier
 	private async connect(config: Config): Promise<WebTransport> {
-		let options: WebTransportOptions = {};
+		const options: WebTransportOptions = {};
 		if (config.fingerprint) {
 			options.serverCertificateHashes = [ config.fingerprint ]
 		}

web/src/transport/message.ts

@@ -1,5 +1,6 @@
-export interface Init {}
-export interface Segment {}
+// TODO fill in required fields
+export type Init = any
+export type Segment = any
 
 export interface Debug {
 	max_bitrate: number

web/src/transport/webtransport.d.ts

@@ -29,7 +29,7 @@ interface WebTransport {
     readonly incomingUnidirectionalStreams: ReadableStream;
 }
 
-declare var WebTransport: {
+declare const WebTransport: {
     prototype: WebTransport;
     new(url: string, options?: WebTransportOptions): WebTransport;
 };
@@ -71,7 +71,7 @@ interface WebTransportError extends DOMException {
     readonly streamErrorCode: number;
 }
 
-declare var WebTransportError: {
+declare const WebTransportError: {
     prototype: WebTransportError;
     new(init?: WebTransportErrorInit): WebTransportError;
 };

web/src/util/deferred.ts

@@ -5,8 +5,8 @@ export default class Deferred<T> {
 
     constructor() {
         // Set initial values so TS stops being annoying.
-        this.resolve = (value: T | PromiseLike<T>) => {};
-        this.reject = (value: T | PromiseLike<T>) => {};
+        this.resolve = (_value: T | PromiseLike<T>) => { /* noop */ };
+        this.reject = (_value: T | PromiseLike<T>) => { /* noop */ };
 
         this.promise = new Promise((resolve, reject) => {
             this.resolve = resolve