Restructure packages

frontend/sync-client/src/utils/data-structures/fix-sized-cache.ts

@@ -1,6 +1,6 @@
 // Implements an in-memory fixed-size cache for document contents,
 
-import type { VaultUpdateId } from "../persistence/database";
+import type { VaultUpdateId } from "../../persistence/database";
 
 // Doubly-linked list node for O(1) LRU operations
 class LRUNode {

frontend/sync-client/src/utils/data-structures/locks.test.ts

@@ -1,7 +1,7 @@
 import { describe, it, beforeEach } from "node:test";
 import assert from "node:assert";
-import { Logger } from "../tracing/logger";
-import type { RelativePath } from "../persistence/database";
+import { Logger } from "../../tracing/logger";
+import type { RelativePath } from "../../persistence/database";
 import { Locks } from "./locks";
 
 describe("withLock", () => {

frontend/sync-client/src/utils/data-structures/locks.ts

@@ -1,4 +1,4 @@
-import type { Logger } from "../tracing/logger";
+import type { Logger } from "../../tracing/logger";
 
 /**
  * Manages exclusive locks on items to prevent concurrent modifications.

frontend/sync-client/src/utils/debugging/log-to-console.ts

@@ -0,0 +1,24 @@
+import type { SyncClient } from "../../sync-client";
+import type { LogLine } from "../../tracing/logger";
+import { LogLevel } from "../../tracing/logger";
+
+export function logToConsole(client: SyncClient): void {
+	client.logger.addOnMessageListener((logLine: LogLine) => {
+		const formatted = `${logLine.timestamp.toISOString()} ${logLine.level} ${logLine.message}`;
+
+		switch (logLine.level) {
+			case LogLevel.ERROR:
+				console.error(formatted);
+				break;
+			case LogLevel.WARNING:
+				console.warn(formatted);
+				break;
+			case LogLevel.INFO:
+				console.info(formatted);
+				break;
+			case LogLevel.DEBUG:
+				console.debug(formatted);
+				break;
+		}
+	});
+}

frontend/sync-client/src/utils/debugging/slow-fetch-factory.ts

@@ -0,0 +1,20 @@
+import { sleep } from "../sleep";
+
+export const slowFetchFactory =
+	(jitterScaleInSeconds: number) =>
+	async (
+		input: string | URL | globalThis.Request,
+		init?: RequestInit
+	): Promise<Response> => {
+		if (jitterScaleInSeconds > 0) {
+			await sleep(((Math.random() * jitterScaleInSeconds) / 2) * 1000);
+		}
+
+		const response = await fetch(input, init);
+
+		if (jitterScaleInSeconds > 0) {
+			await sleep(((Math.random() * jitterScaleInSeconds) / 2) * 1000);
+		}
+
+		return response;
+	};

frontend/sync-client/src/utils/debugging/slow-web-socket-factory.ts

@@ -0,0 +1,80 @@
+import { sleep } from "../sleep";
+import { Locks } from "../data-structures/locks";
+import type { Logger } from "../../tracing/logger";
+
+export function slowWebSocketFactory(
+	jitterScaleInSeconds: number,
+	logger: Logger
+): typeof WebSocket {
+	return class FlakyWebSocket extends WebSocket {
+		private static readonly RECEIVE_KEY = "websocket-receive";
+		private static readonly SEND_KEY = "websocket-send";
+
+		private readonly locks = new Locks(logger);
+
+		public set onopen(callback: (event: Event) => void) {
+			super.onopen = async (event: Event): Promise<void> => {
+				if (jitterScaleInSeconds > 0) {
+					await sleep(Math.random() * jitterScaleInSeconds * 1000);
+				}
+
+				callback(event);
+			};
+		}
+
+		public set onmessage(callback: (event: MessageEvent) => void) {
+			super.onmessage = async (event: MessageEvent): Promise<void> => {
+				await this.locks.withLock(
+					FlakyWebSocket.RECEIVE_KEY,
+					async () => {
+						if (jitterScaleInSeconds > 0) {
+							await sleep(
+								Math.random() * jitterScaleInSeconds * 1000
+							);
+						}
+
+						callback(event);
+					}
+				);
+			};
+		}
+
+		public set onclose(callback: (event: CloseEvent) => void) {
+			super.onclose = async (event: CloseEvent): Promise<void> => {
+				if (jitterScaleInSeconds > 0) {
+					await sleep(Math.random() * jitterScaleInSeconds * 1000);
+				}
+				callback(event);
+			};
+		}
+
+		public set onerror(callback: (event: Event) => void) {
+			super.onerror = async (event: Event): Promise<void> => {
+				if (jitterScaleInSeconds > 0) {
+					await sleep(Math.random() * jitterScaleInSeconds * 1000);
+				}
+				callback(event);
+			};
+		}
+
+		public send(
+			data: string | ArrayBufferLike | Blob | ArrayBufferView
+		): void {
+			this.waitingSend(data).catch((error: unknown) => {
+				logger.error(`Error sending WebSocket message: ${error}`);
+			});
+		}
+
+		private async waitingSend(
+			data: string | ArrayBufferLike | Blob | ArrayBufferView
+		): Promise<void> {
+			// maintain message order
+			await this.locks.withLock(FlakyWebSocket.SEND_KEY, async () => {
+				if (jitterScaleInSeconds > 0) {
+					await sleep(Math.random() * jitterScaleInSeconds * 1000);
+				}
+				super.send(data);
+			});
+		}
+	} as unknown as typeof WebSocket;
+}

frontend/sync-client/src/utils/deserialize.ts

@@ -1,5 +0,0 @@
-import { base64ToBytes } from "byte-base64";
-
-export function deserialize(data: string): Uint8Array {
-	return base64ToBytes(data);
-}

frontend/sync-client/src/utils/is-equal-bytes.test.ts

@@ -1,29 +0,0 @@
-import { describe, it } from "node:test";
-import assert from "node:assert";
-import { isEqualBytes } from "./is-equal-bytes";
-
-describe("isEqualBytes", () => {
-	it("should return true for equal byte arrays", () => {
-		const bytes1 = new Uint8Array([1, 2, 3, 4]);
-		const bytes2 = new Uint8Array([1, 2, 3, 4]);
-		assert.strictEqual(isEqualBytes(bytes1, bytes2), true);
-	});
-
-	it("should return false for byte arrays of different lengths", () => {
-		const bytes1 = new Uint8Array([1, 2, 3, 4]);
-		const bytes2 = new Uint8Array([1, 2, 3]);
-		assert.strictEqual(isEqualBytes(bytes1, bytes2), false);
-	});
-
-	it("should return true for empty byte arrays", () => {
-		const bytes1 = new Uint8Array([]);
-		const bytes2 = new Uint8Array([]);
-		assert.strictEqual(isEqualBytes(bytes1, bytes2), true);
-	});
-
-	it("should return false for byte arrays with same length but different content", () => {
-		const bytes1 = new Uint8Array([1, 2, 3, 4]);
-		const bytes2 = new Uint8Array([4, 3, 2, 1]);
-		assert.strictEqual(isEqualBytes(bytes1, bytes2), false);
-	});
-});

frontend/sync-client/src/utils/is-equal-bytes.ts

@@ -1,13 +0,0 @@
-export function isEqualBytes(bytes1: Uint8Array, bytes2: Uint8Array): boolean {
-	if (bytes1.length !== bytes2.length) {
-		return false;
-	}
-
-	for (let i = 0; i < bytes1.length; i++) {
-		if (bytes1[i] !== bytes2[i]) {
-			return false;
-		}
-	}
-
-	return true;
-}