snowpack
Version:
The ESM-powered frontend build tool. Fast, lightweight, unbundled.
82 lines (81 loc) • 3.81 kB
JavaScript
;
var __importDefault = (this && this.__importDefault) || function (mod) {
return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.startHmrEngine = void 0;
const path_1 = __importDefault(require("path"));
const signal_exit_1 = __importDefault(require("signal-exit"));
const hmr_server_engine_1 = require("../hmr-server-engine");
const util_1 = require("../util");
function startHmrEngine(inMemoryBuildCache, server, serverPort, config) {
const { hmrDelay } = config.devOptions;
const hmrPort = config.devOptions.hmrPort || serverPort;
const hmrEngine = new hmr_server_engine_1.EsmHmrEngine({ server, port: hmrPort, delay: hmrDelay });
signal_exit_1.default(() => {
hmrEngine.disconnectAllClients();
});
// Live Reload + File System Watching
function updateOrBubble(url, visited) {
if (visited.has(url)) {
return;
}
const node = hmrEngine.getEntry(url);
const isBubbled = visited.size > 0;
if (node && node.isHmrEnabled) {
hmrEngine.broadcastMessage({ type: 'update', url, bubbled: isBubbled });
}
visited.add(url);
if (node && node.isHmrAccepted) {
// Found a boundary, no bubbling needed
}
else if (node && node.dependents.size > 0) {
node.dependents.forEach((dep) => {
hmrEngine.markEntryForReplacement(node, true);
updateOrBubble(dep, visited);
});
}
else {
// We've reached the top, trigger a full page refresh
hmrEngine.broadcastMessage({ type: 'reload' });
}
}
function handleHmrUpdate(fileLoc, originalUrl) {
// CSS files may be loaded directly in the client (not via JS import / .proxy.js)
// so send an "update" event to live update if thats the case.
if (util_1.hasExtension(originalUrl, '.css') && !util_1.hasExtension(originalUrl, '.module.css')) {
hmrEngine.broadcastMessage({ type: 'update', url: originalUrl, bubbled: false });
}
// Append ".proxy.js" to Non-JS files to match their registered URL in the
// client app.
let updatedUrl = originalUrl;
if (!util_1.hasExtension(updatedUrl, '.js')) {
updatedUrl += '.proxy.js';
}
// Check if a virtual file exists in the resource cache (ex: CSS from a
// Svelte file) If it does, mark it for HMR replacement but DONT trigger a
// separate HMR update event. This is because a virtual resource doesn't
// actually exist on disk, so we need the main resource (the JS) to load
// first. Only after that happens will the CSS exist.
const virtualCssFileUrl = updatedUrl.replace(/.js$/, '.css');
const virtualNode = virtualCssFileUrl.includes(path_1.default.basename(fileLoc)) &&
hmrEngine.getEntry(`${virtualCssFileUrl}.proxy.js`);
if (virtualNode) {
hmrEngine.markEntryForReplacement(virtualNode, true);
}
// If the changed file exists on the page, trigger a new HMR update.
if (hmrEngine.getEntry(updatedUrl)) {
updateOrBubble(updatedUrl, new Set());
return;
}
// Otherwise, reload the page if the file exists in our hot cache (which
// means that the file likely exists on the current page, but is not
// supported by HMR (HTML, image, etc)).
if (inMemoryBuildCache.has(util_1.getCacheKey(fileLoc, { isSSR: false, mode: config.mode }))) {
hmrEngine.broadcastMessage({ type: 'reload' });
return;
}
}
return { hmrEngine, handleHmrUpdate };
}
exports.startHmrEngine = startHmrEngine;