microsoft/qdk
Publicmirrored fromhttps://github.com/microsoft/qdkAvailable
source/npm/qsharp/src/workers/browser.ts
111lines · modecode
| 1 | // Copyright (c) Microsoft Corporation. |
| 2 | // Licensed under the MIT License. |
| 3 | |
| 4 | import * as wasm from "../../lib/web/qsc_wasm.js"; |
| 5 | import { log } from "../log.js"; |
| 6 | import { |
| 7 | IServiceEventMessage, |
| 8 | IServiceProxy, |
| 9 | RequestMessage, |
| 10 | ServiceMethods, |
| 11 | ServiceProtocol, |
| 12 | createProxyInternal, |
| 13 | initService, |
| 14 | } from "./common.js"; |
| 15 | |
| 16 | /** |
| 17 | * Creates an initializes a service, setting it up to receive requests. |
| 18 | * This function to be is used in the worker. |
| 19 | * |
| 20 | * @param serviceProtocol An object that describes the service: its constructor, methods and events |
| 21 | * @returns A message handler to be assigned to the `self.onmessage` handler in a web worker |
| 22 | */ |
| 23 | export function createWorker< |
| 24 | TService extends ServiceMethods<TService>, |
| 25 | TServiceEventMsg extends IServiceEventMessage, |
| 26 | >( |
| 27 | serviceProtocol: ServiceProtocol<TService, TServiceEventMsg>, |
| 28 | ): (e: MessageEvent) => void { |
| 29 | let invokeService: ((req: RequestMessage<TService>) => Promise<void>) | null = |
| 30 | null; |
| 31 | |
| 32 | // This export should be assigned to 'self.onmessage' in a WebWorker |
| 33 | return function messageHandler(e: MessageEvent) { |
| 34 | const data = e.data; |
| 35 | |
| 36 | if (!data.type || typeof data.type !== "string") { |
| 37 | log.error(`Unrecognized msg: ${data}`); |
| 38 | return; |
| 39 | } |
| 40 | |
| 41 | switch (data.type) { |
| 42 | case "init": |
| 43 | { |
| 44 | wasm.initSync({ module: data.wasmModule }); |
| 45 | |
| 46 | invokeService = initService<TService, TServiceEventMsg>( |
| 47 | self.postMessage.bind(self), |
| 48 | serviceProtocol, |
| 49 | wasm, |
| 50 | data.qscLogLevel, |
| 51 | ); |
| 52 | } |
| 53 | break; |
| 54 | default: |
| 55 | if (!invokeService) { |
| 56 | log.error( |
| 57 | `Received message before the service was initialized: %o`, |
| 58 | data, |
| 59 | ); |
| 60 | } else { |
| 61 | invokeService(data); |
| 62 | } |
| 63 | } |
| 64 | }; |
| 65 | } |
| 66 | |
| 67 | /** |
| 68 | * Creates and initializes a service in a web worker, and returns a proxy for the service |
| 69 | * to be used from the main thread. |
| 70 | * |
| 71 | * @param workerArg The service web worker or the URL of the web worker script. |
| 72 | * @param wasmModule The wasm module to initialize the service with |
| 73 | * @param serviceProtocol An object that describes the service: its constructor, methods and events |
| 74 | * @returns A proxy object that implements the service interface. |
| 75 | * This interface can now be used as if calling into the real service, |
| 76 | * and the calls will be proxied to the web worker. |
| 77 | */ |
| 78 | export function createProxy< |
| 79 | TService extends ServiceMethods<TService>, |
| 80 | TServiceEventMsg extends IServiceEventMessage, |
| 81 | >( |
| 82 | workerArg: string | Worker, |
| 83 | wasmModule: WebAssembly.Module, |
| 84 | serviceProtocol: ServiceProtocol<TService, TServiceEventMsg>, |
| 85 | ): TService & IServiceProxy { |
| 86 | // Create or use the WebWorker |
| 87 | const worker = |
| 88 | typeof workerArg === "string" ? new Worker(workerArg) : workerArg; |
| 89 | |
| 90 | // Send it the Wasm module to instantiate |
| 91 | worker.postMessage({ |
| 92 | type: "init", |
| 93 | wasmModule, |
| 94 | qscLogLevel: log.getLogLevel(), |
| 95 | }); |
| 96 | |
| 97 | // If you lose the 'this' binding, some environments have issues |
| 98 | const postMessage = worker.postMessage.bind(worker); |
| 99 | const onTerminate = () => worker.terminate(); |
| 100 | |
| 101 | // Create the proxy which will forward method calls to the worker |
| 102 | const proxy = createProxyInternal<TService, TServiceEventMsg>( |
| 103 | postMessage, |
| 104 | onTerminate, |
| 105 | serviceProtocol.methods, |
| 106 | ); |
| 107 | |
| 108 | // Let proxy handle response and event messages from the worker |
| 109 | worker.onmessage = (ev) => proxy.onMsgFromWorker(ev.data); |
| 110 | return proxy; |
| 111 | } |
| 112 | |