Initial commit!

.editorconfig

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+root = true
+
+[*]
+indent_style = tab
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true
+
+[{package.json,.*rc,*.yml}]
+indent_style = space
+indent_size = 2
+
+[*.md]
+trim_trailing_whitespace = false

.gitignore

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+node_modules
+dist
+build
+.DS_Store
+package-lock.json

README.md

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+<p align="center">
+  <img src="https://i.imgur.com/JLAwk0S.png" width="300" height="300" alt="workerize-loader">
+  <br>
+  <a href="https://www.npmjs.org/package/workerize"><img src="https://img.shields.io/npm/v/workerize.svg?style=flat" alt="npm"></a> <a href="https://travis-ci.org/developit/workerize"><img src="https://travis-ci.org/developit/workerize.svg?branch=master" alt="travis"></a>
+</p>
+
+# Workerize
+
+**NOTE:** If you're using Webpack, try [workerize-loader](https://github.com/developit/workerize-loader).
+
+> Moves a module into a Web Worker, automatically reflecting exported functions as asynchronous proxies.
+
+- Bundles a tiny, purpose-built RPC implementation into your app
+- If exported module methods are already async, signature is unchanged
+- Supports synchronous and asynchronous worker functions
+- Works beautifully with async/await
+
+
+## Install
+
+```sh
+npm install --save workerize
+```
+
+
+### Usage
+
+**worker.js**:
+
+```js
+let worker = workerize(`
+	export function add(a, b) {
+		// block for half a second to demonstrate asynchronicity
+		let start = Date.now();
+		while (Date.now()-start < 250);
+		return a + b;
+	}
+`);
+
+(async () => {
+	console.log('3 + 9 = ', await worker.add(3, 9));
+	console.log('1 + 2 = ', await worker.add(1, 2));
+})();
+```
+
+### License
+
+[MIT License](LICENSE.md) © [Jason Miller](https://jasonformat.com)

package.json

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+{
+  "name": "workerize",
+  "version": "0.1.0",
+  "description": "Run a module into a Web Worker.",
+  "main": "dist/workerize.js",
+  "module": "src/index.js",
+  "scripts": {
+    "build": "microbundle",
+    "prepublishOnly": "npm run build",
+    "test": "echo \"Error: no test specified\" && exit 0"
+  },
+  "keywords": [],
+  "author": "Jason Miller <jason@developit.ca> (http://jasonformat.com)",
+  "license": "ISC",
+  "devDependencies": {
+    "microbundle": "^0.2.4"
+  }
+}

src/index.js

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+
+/** TODO:
+ *	- pooling (+ load balancing by tracking # of open calls)
+ *  - queueing (worth it? sortof free via postMessage already)
+ *
+ *	@example
+ *	let worker = workerize(`
+ *		export function add(a, b) {
+ *			// block for half a second to demonstrate asynchronicity
+ *			let start = Date.now();
+ *			while (Date.now()-start < 250);
+ *			return a + b;
+ *		}
+ *	`);
+ *	(async () => {
+ *		console.log('3 + 9 = ', await worker.add(3, 9));
+ *		console.log('1 + 2 = ', await worker.add(1, 2));
+ *	})();
+ */
+
+
+export default function workerize(code) {
+	let exports = {};
+	let exportsObjName = `__EXPORTS_${Math.random().toString().substring(2)}__`;
+	if (typeof code==='function') code = `(${toCode(code)})(${exportsObjName})`;
+	code = toCjs(code, exportsObjName, exports);
+	code += `\n(${toCode(setup)})(self, ${exportsObjName}, {})`;
+	let blob = new Blob([code], {
+			type: 'application/javascript'
+		}),
+		url = URL.createObjectURL(blob),
+		worker = new Worker(url),
+		counter = 0,
+		callbacks = {};
+	worker.kill = signal => {
+		worker.postMessage({ type: 'KILL', signal });
+		setTimeout(worker.terminate);
+	};
+	let term = worker.terminate;
+	worker.terminate = () => {
+		URL.revokeObjectURL(url);
+		worker.terminate();
+	};
+	worker.rpcMethods = {};
+	function setup(ctx, rpcMethods, callbacks) {
+		/*
+		ctx.expose = (methods, replace) => {
+			if (typeof methods==='string') {
+				rpcMethods[methods] = replace;
+			}
+			else {
+				if (replace===true) rpcMethods = {};
+				Object.assign(rpcMethods, methods);
+			}
+		};
+		*/
+		ctx.addEventListener('message', ({ data }) => {
+			if (data.type==='RPC') {
+				let id = data.id;
+				if (id!=null) {
+					if (data.method) {
+						let method = rpcMethods[data.method];
+						if (method==null) {
+							ctx.postMessage({ type: 'RPC', id, error: 'NO_SUCH_METHOD' });
+						}
+						else {
+							Promise.resolve()
+								.then( () => method.apply(null, data.params) )
+								.then( result => { ctx.postMessage({ type: 'RPC', id, result }); })
+								.catch( error => { ctx.postMessage({ type: 'RPC', id, error }); });
+						}
+					}
+					else {
+						let callback = callbacks[id];
+						if (callback==null) throw Error(`Unknown callback ${id}`);
+						delete callbacks[id];
+						if (data.error) callback.reject(Error(data.error));
+						else callback.resolve(data.result);
+					}
+				}
+			}
+		});
+	}
+	setup(worker, worker.rpcMethods, callbacks);
+	worker.call = (method, params) => new Promise( (resolve, reject) => {
+		let id = `rpc${++counter}`;
+		callbacks[id] = { method, resolve, reject };
+		worker.postMessage({ type: 'RPC', id, method, params });
+	});
+	for (let i in exports) {
+		if (exports.hasOwnProperty(i) && !(i in worker)) {
+			worker[i] = (...args) => worker.call(i, args);
+		}
+	}
+	return worker;
+}
+
+function toCode(func) {
+	return Function.prototype.toString.call(func);
+}
+
+function toCjs(code, exportsObjName, exports) {
+	exportsObjName = exportsObjName || 'exports';
+	exports = exports || {};
+	code = code.replace(/^(\s*)export\s+default\s+/m, (s, before) => {
+		exports.default = true;
+		return `${before}${exportsObjName}.default = `;
+	});
+	code = code.replace(/^(\s*)export\s+(function|const|let|var)(\s+)([a-zA-Z$_][a-zA-Z0-9$_]*)/m, (s, before, type, ws, name) => {
+		exports[name] = true;
+		return `${before}${exportsObjName}.${name} = ${type}${ws}${name}`;
+	});
+	return `var ${exportsObjName} = {};\n${code}\n${exportsObjName};`;
+}