Fix oauth2 client basic http auth usage

Per RFC 6749 section 2.3.1 the client_id and client_secret need
to be encoded using "application/x-www-form-urlencoded" encoding
first before just being send to the server as is.

src/oauth2Client.test.ts

@@ -44,7 +44,7 @@ suite('oauth2client', () => {
 		let tokenErr: Error | undefined;
 		tokenHandler = async (req) => {
 			try {
-				equal(req.headers.authorization, 'Basic dXNlcjE6cGFzczE=');
+				equal(req.headers.authorization, 'Basic dXNlcjE6cGFzczElM0QlM0Q=');
 				equal(req.headers['content-type'], 'application/x-www-form-urlencoded');
 				const params = new URLSearchParams(req.body as string);
 				equal(params.get('grant_type'), 'client_credentials');
@@ -61,7 +61,7 @@ suite('oauth2client', () => {
 		const token = await getAccessToken(
 			`http://localhost:${PORT}`,
 			'user1',
-			'pass1',
+			'pass1==',
 			'tachyon.lobby',
 		);
 		if (tokenErr) throw tokenErr;

src/oauth2Client.ts

@@ -107,7 +107,9 @@ export async function getAccessToken(
 	}
 
 	// Now let's try to get a new access token
-	const basicToken = Buffer.from(`${clientId}:${clientSecret}`).toString('base64');
+	const basicToken = Buffer.from(
+		`${encodeURIComponent(clientId)}:${encodeURIComponent(clientSecret)}`,
+	).toString('base64');
 	const tokenParams = new URLSearchParams({
 		grant_type: 'client_credentials',
 	});

src/tachyonServer.fake.ts

@@ -153,7 +153,10 @@ export async function createTachyonServer(options?: TachyonServerOpts) {
 	await server.register(FastifyFormBody);
 	await server.register(FastifyBasicAuth, {
 		validate: async (username, password, _req, reply) => {
-			if (username !== opts.clientId || password !== opts.clientSecret) {
+			if (
+				decodeURIComponent(username) !== opts.clientId ||
+				decodeURIComponent(password) !== opts.clientSecret
+			) {
 				reply.status(401);
 				reply.header('www-authenticate', 'Basic realm="tachyon_oauth2"');
 				return new Oauth2Error('invalid_client');