carton/entrypoint/dev.js

96 lines
2.6 KiB
JavaScript

// Copyright 2020 Carton contributors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
import { SwiftRuntime } from "javascript-kit-swift";
import { WASI } from "@wasmer/wasi";
import { WasmFs } from "@wasmer/wasmfs";
import ReconnectingWebSocket from "reconnecting-websocket";
const swift = new SwiftRuntime();
// Instantiate a new WASI Instance
const wasmFs = new WasmFs();
const socket = new ReconnectingWebSocket(`ws://${location.host}/watcher`);
socket.addEventListener("message", (message) => {
if (message.data === "reload") {
location.reload();
}
});
// Output stdout and stderr to console
const originalWriteSync = wasmFs.fs.writeSync;
wasmFs.fs.writeSync = (fd, buffer, offset, length, position) => {
const text = new TextDecoder("utf-8").decode(buffer);
if (text !== "\n") {
switch (fd) {
case 1:
console.log(text);
break;
case 2:
console.error(text);
const prevLimit = Error.stackTraceLimit;
Error.stackTraceLimit = 1000
socket.send(
JSON.stringify({
kind: "stackTrace",
stackTrace: new Error().stack,
})
);
Error.stackTraceLimit = prevLimit;
break;
}
}
return originalWriteSync(fd, buffer, offset, length, position);
};
const wasi = new WASI({
args: [],
env: {},
bindings: {
...WASI.defaultBindings,
fs: wasmFs.fs,
},
});
const startWasiTask = async () => {
// Fetch our Wasm File
const response = await fetch("/main.wasm");
const responseArrayBuffer = await response.arrayBuffer();
// Instantiate the WebAssembly file
const wasmBytes = new Uint8Array(responseArrayBuffer).buffer;
const { instance } = await WebAssembly.instantiate(wasmBytes, {
wasi_snapshot_preview1: wasi.wasiImport,
javascript_kit: swift.importObjects(),
});
swift.setInstance(instance);
// Start the WebAssembly WASI instance
wasi.start(instance);
};
function handleError(e) {
console.error(e);
if (e instanceof WebAssembly.RuntimeError) {
console.log(e.stack);
}
}
try {
startWasiTask().catch(handleError);
} catch (e) {
handleError(e);
}