rollup-plugin-web-worker-loader
Version:
Rollup plugin to handle Web Workers
269 lines (249 loc) • 12.4 kB
JavaScript
const fs = require('fs');
const path = require('path');
const rollup = require('rollup');
const fixMapSources = require('./utils/fixMapSources');
const extractSource = require('./utils/extractSource');
const buildWorkerCode = require('./utils/buildWorkerCode');
module.exports = function workerLoaderPlugin(config = null) {
const targetPlatform = config && config.hasOwnProperty('targetPlatform') ? config.targetPlatform : 'browser';
const sourcemap = config && config.hasOwnProperty('sourcemap') ? config.sourcemap : false;
const loadPath = config && config.hasOwnProperty('loadPath') ? config.loadPath : '';
const preserveSource = config && config.hasOwnProperty('preserveSource') ? config.preserveSource : false;
const enableUnicode = config && config.hasOwnProperty('enableUnicodeSupport') ? config.enableUnicodeSupport : false;
const pattern = config && config.hasOwnProperty('pattern') ? config.pattern : /web-worker:(.+)/;
const skipPlugins = new Set(config && config.hasOwnProperty('skipPlugins') ? config.skipPlugins : [
'liveServer',
'serve',
'livereload',
]);
let inline = config && config.hasOwnProperty('inline') ? config.inline : true;
const forceInline = inline && config && config.hasOwnProperty('forceInline') ? config.forceInline : false;
const helperPattern = /^\0(?:[0-9]+::)?rollup-plugin-web-worker-loader::helper(?:::)?/;
const idMap = new Map();
const exclude = new Set();
let projectOptions = null;
let basePath = null;
let configuredFileName = null;
let forceInlineCounter = 0;
return {
name: 'rollup-plugin-web-worker-loader',
options(options) {
if (!projectOptions) {
projectOptions = Object.assign({}, options);
if (options.plugins && options.plugins.length) {
const plugins = [];
options.plugins.forEach(plugin => {
if (skipPlugins.has(plugin.name)) return;
plugins.push(plugin);
});
projectOptions.plugins = plugins;
const cwd = process.cwd();
if (typeof options.input === 'string') {
try {
const entry = require.resolve(options.input, { paths: [cwd] });
basePath = path.dirname(entry);
} catch (e) { /* EMPTY */ }
} else if (Array.isArray(options.input)) {
let componentCount = Number.MAX_SAFE_INTEGER;
let shortestPath = null;
for (let i = 0, n = options.input.length; i < n; ++i) {
try {
const entry = require.resolve(options.input[i], { paths: [cwd] });
const entryPath = path.dirname(entry);
const components = entryPath.split(path.sep);
if (components.length < componentCount) {
componentCount = components.length;
shortestPath = entryPath;
}
} catch (e) { /* EMPTY */ }
}
basePath = shortestPath;
} else {
const keys = Object.keys(options.input);
let componentCount = Number.MAX_SAFE_INTEGER;
let shortestPath = null;
for (let i = 0, n = keys.length; i < n; ++i) {
const input = options.input[keys[i]];
try {
const entry = require.resolve(input, { paths: [cwd] });
const entryPath = path.dirname(entry);
const components = entryPath.split(path.sep);
if (components.length < componentCount) {
componentCount = components.length;
shortestPath = entryPath;
}
} catch (e) { /* EMPTY */ }
}
basePath = shortestPath;
}
if (!basePath) {
basePath = '.';
}
}
}
return null;
},
resolveId(importee, importer) {
const match = importee.match(pattern);
if (importee.startsWith('\0rollup-plugin-web-worker-loader::helper')) {
if (forceInline) {
return `\0${forceInlineCounter++}::${importee.substr(1)}`;
}
return importee;
} else if (match && match.length) {
const name = match[match.length - 1];
if (!idMap.has(name)) {
let target = null;
if (importer) {
const folder = path.dirname(importer);
const paths = require.resolve.paths(importer);
paths.push(folder);
target = require.resolve(name, {paths});
} else if (path.isAbsolute(name)) {
target = name;
}
if (target) {
const prefixed = `\0rollup-plugin-worker-loader::module:${forceInline ? `:${forceInlineCounter++}:` : ''}${name}`;
if (!idMap.has(prefixed)) {
const inputOptions = Object.assign({}, projectOptions, {
input: target,
});
idMap.set(prefixed, {
workerID: `web-worker-${idMap.size}.js`,
chunk: null,
inputOptions,
target,
});
}
if (idMap.has(prefixed)) {
return prefixed;
}
return target;
}
}
}
return null;
},
load(id) {
return new Promise((resolve, reject) => {
const helperMatch = helperPattern.exec(id);
if (helperMatch) {
const helperParts = id.substr(helperMatch[0].length).split('::');
const helperPath = path.resolve(__dirname, 'helper', ...helperParts) + '.js';
fs.readFile(helperPath, 'utf8', (err, data) => {
if (err) {
reject(err);
}
resolve(data);
});
} else if (idMap.has(id) && !exclude.has(id)) {
if (!inline) {
/* inline requires rollup version 1.9.2 or higher */
const version = this.meta.rollupVersion.split('.');
if (version.length !== 3) {
this.warn('Unknown rollup version');
inline = true;
} else {
const major = parseInt(version[0], 10);
const minor = parseInt(version[1], 10);
const patch = parseInt(version[2], 10);
if (
isNaN(major) ||
isNaN(minor) ||
isNaN(patch) ||
major < 1 ||
(major === 1 && minor < 9) ||
(major === 1 && minor === 9 && patch < 2)
) {
this.warn(`Rollup version 1.9.2 or higher is required for emitting a worker file (current version:${this.meta.rollupVersion}). See https://github.com/rollup/rollup/issues/2801`);
inline = true;
}
}
}
const {inputOptions, workerID, target} = idMap.get(id);
exclude.add(id);
exclude.add(target);
rollup.rollup(inputOptions).then(bundle => {
exclude.delete(id);
exclude.delete(target);
bundle.generate({format: 'es', name: id, sourcemap: true}).then(result => {
const output = result.output;
let chunk = null;
for (const ch of output) {
if (!ch.isAsset) {
chunk = ch;
break;
}
}
if (chunk !== null) {
/* add dependencies to watch list */
const deps = Object.keys(chunk.modules);
for (const dep of deps) {
this.addWatchFile(dep);
}
let map = null;
let source;
if (inline) {
source = extractSource(chunk.code, chunk.exports, preserveSource);
map = null;
if (sourcemap) {
map = fixMapSources(chunk, basePath);
}
} else {
source = path.posix.join(loadPath, workerID);
chunk.fileName = workerID;
idMap.get(id).chunk = chunk;
}
resolve({
code: buildWorkerCode(source, map, {
inline,
preserveSource,
enableUnicode,
targetPlatform,
}),
});
} else {
resolve(null);
}
}).catch(reject);
}).catch(reason => {
exclude.delete(id);
exclude.delete(target);
reject(reason);
});
} else {
resolve(null);
}
});
},
transform(code, id) {
if (idMap.has(id) && !exclude.has(id)) {
const {inputOptions} = idMap.get(id);
return { code, map: `{"version":3,"file":"${path.basename(inputOptions.input)}","sources":[],"sourcesContent":[],"names":[],"mappings":""}` };
}
return null;
},
outputOptions(options) {
if (!inline && options.file && !options.dir) {
configuredFileName = path.basename(options.file);
return Object.assign({}, options, {
file: null,
dir: path.dirname(options.file),
});
}
return null;
},
generateBundle(options, bundle, isWrite) {
if (!inline && isWrite) {
if (configuredFileName && Object.keys(bundle).length === 1) {
bundle[Object.keys(bundle)[0]].fileName = configuredFileName;
}
for (const worker of idMap) {
if (worker[1].chunk && !bundle[worker[1].workerID]) {
bundle[worker[1].workerID] = worker[1].chunk;
}
}
}
},
};
};