refac: add esm dist format, rewrite in typescript

.gitignore

@@ -1 +1,2 @@
+dist/
 node_modules/

index.ts

@@ -0,0 +1,64 @@
+// Imports
+
+import type * as http from 'http';
+import readCredentials from 'basic-auth';
+import serveStatic from 'serve-static';
+
+// Types
+
+interface Options {
+  directory?: string;
+  realm?: string;
+
+  onAuthFailed?: (res) => void;
+}
+
+type ValidatorFunction = (username: string, password: string) => boolean;
+
+// Variables
+
+const optionsDefaultValues: Options = {
+  directory: process.cwd(),
+  realm: 'default-realm',
+
+  onAuthFailed: res => res.write('401 Unauthorized') // by default send a basic error message
+};
+
+// Exports
+
+export default (url: string, validator: ValidatorFunction, optionsUserValues: Options = {}): http.RequestListener => {
+  // Check required parameters
+
+  if (typeof url !== 'string')
+    throw new Error('`url` is not a string');
+  if (typeof validator !== 'function')
+    throw new Error('`validator` is not a function');
+
+  // Make sure all options are initialized
+
+  const options = {
+    ...optionsDefaultValues,
+    ...optionsUserValues,
+  };
+
+  // Everything OK
+
+  const serve = serveStatic(options.directory);
+
+  return (req: http.IncomingMessage, res: http.ServerResponse) => {
+    if (req.url.startsWith(url)) { // if request URL requires authentication
+      const credentials = readCredentials(req);
+
+      if (!credentials || !validator(credentials.name, credentials.pass)) { // if credentials are missing / invalid
+        res.writeHead(401, { 'WWW-Authenticate': `Basic realm="${options.realm}"` });
+        options.onAuthFailed(res); // tell the user
+        return res.end(); // don't serve the requested file
+      }
+    }
+
+    serve(req, res, () => {
+      res.statusCode = 404;
+      res.end('404 Not Found');
+    });
+  };
+};

package.json

@@ -11,10 +11,21 @@
   ],
   "homepage": "https://github.com/flawyte/static-auth",
   "license": "MIT",
-  "main": "index.js",
   "repository": "github:flawyte/static-auth",
+
+  "main": "dist/static-auth.js",
+  "module": "dist/static-auth.esm.js",
+  "source": "index.ts",
+
+  "scripts": {
+    "build": "microbundle"
+  },
+
   "dependencies": {
     "basic-auth": "^2.0.1",
     "serve-static": "^1.14.1"
+  },
+  "devDependencies": {
+    "microbundle": "^0.12.0"
   }
 }