squiggle/my-react-app/watcher.js
2020-02-05 21:09:27 +00:00

40 lines
1.6 KiB
JavaScript

// This is our simple, robust watcher. It hooks into the BuckleScript build
// system to listen for build events.
// See package.json's `start` script and `./node_modules/.bin/bsb --help`
// Btw, if you change this file and reload the page, your browser cache
// _might_ not pick up the new version. If you're in Chrome, do Force Reload.
var websocketReloader;
var LAST_SUCCESS_BUILD_STAMP = localStorage.getItem('LAST_SUCCESS_BUILD_STAMP') || 0;
// package.json's `start` script's `bsb -ws _` means it'll pipe build events
// through a websocket connection to a default port of 9999. This is
// configurable, e.g. `-ws 5000`
var webSocketPort = 9999;
function setUpWebSocket() {
if (websocketReloader == null || websocketReloader.readyState !== 1) {
try {
websocketReloader = new WebSocket(`ws://localhost:${webSocketPort}`);
websocketReloader.onmessage = (message) => {
var newData = JSON.parse(message.data).LAST_SUCCESS_BUILD_STAMP;
if (newData > LAST_SUCCESS_BUILD_STAMP) {
LAST_SUCCESS_BUILD_STAMP = newData;
localStorage.setItem('LAST_SUCCESS_BUILD_STAMP', LAST_SUCCESS_BUILD_STAMP);
// Refresh the page! This will naturally re-run everything,
// including our moduleserve which will re-resolve all the modules.
// No stable build!
location.reload(true);
}
}
} catch (exn) {
console.error("The watcher tried to connect to web socket, but failed. Here's the message:");
console.error(exn);
}
}
};
setUpWebSocket();
setInterval(setUpWebSocket, 2000);