OpenDiachronicMaps/geotiffGesture/geotiffJS/scripts/serialize-workers.cjs

104 lines
2.7 KiB
JavaScript

/* eslint-disable import/no-commonjs */
/* eslint-disable import/no-extraneous-dependencies */
const path = require('path');
const { babel } = require('@rollup/plugin-babel');
const resolve = require('@rollup/plugin-node-resolve').nodeResolve;
const common = require('@rollup/plugin-commonjs');
const rollup = require('rollup');
const { terser } = require('rollup-plugin-terser');
const fse = require('fs-extra');
async function build(input, { minify = true } = {}) {
const plugins = [
{
name: 'remove export let create',
transform(code, id) {
if (id !== input) {
return null;
}
return code.replace('export let create;', '');
},
},
common(),
resolve(),
babel({
babelHelpers: 'runtime',
presets: [
[
'@babel/preset-env',
{
modules: false,
targets: 'last 2 versions, not dead',
},
],
],
plugins: ['@babel/plugin-transform-runtime'],
}),
];
if (minify) {
plugins.push(terser());
}
plugins.push({
name: 'serialize worker and export create function',
renderChunk(code) {
return `
import Worker from 'web-worker';
export function create() {
const source = ${JSON.stringify(code)};
return new Worker(typeof Buffer !== 'undefined'
? 'data:application/javascript;base64,' + Buffer.from(source, 'binary').toString('base64')
: URL.createObjectURL(new Blob([source], {type: 'application/javascript'})));
}
`;
},
});
const bundle = await rollup.rollup({
input,
plugins,
inlineDynamicImports: true,
});
const { output } = await bundle.generate({ format: 'es' });
if (output.length !== 1) {
throw new Error(`Unexpected output length: ${output.length}`);
}
const chunk = output[0];
if (chunk.isAsset) {
throw new Error('Expected a chunk, got an asset');
}
return chunk;
}
exports.build = build;
/**
* Creates modules with inlined versions of the worker sources. These modules
* export a `create` function for creating a worker.
*/
async function main() {
const inputDir = path.join(__dirname, '../src/worker');
const outputDir = path.join(__dirname, '../dist-module/worker');
await fse.ensureDir(outputDir);
const entries = await fse.readdir(inputDir);
for (const entry of entries) {
if (entry.endsWith('.js')) {
const chunk = await build(path.join(inputDir, entry));
await fse.writeFile(path.join(outputDir, entry), chunk.code);
}
}
}
if (require.main === module) {
main().catch((err) => {
process.stderr.write(`${err.stack}\n`);
process.exit(1);
});
}