implement cat script

cc-tweaked/host.ts

@@ -1,38 +1,30 @@
 #!/bin/env -S deno run --allow-read --allow-net
 
 async function main() {
-	const [program_path] = Deno.args;
-	if (program_path === undefined) fail_with("Usage: host.ts <program_path>");
 	const port = 1728;
-	const server = Deno.listen({ port });
-	console.log("listening on port", port);
-	for await (const connection of server) handle(connection, program_path);
+	const server = Deno.serve({ port }, (request) => handle(request));
+	await server.finished;
 }
 
-async function handle(connection: Deno.TcpConn, program_path: string) {
-	console.log("serving");
-	const file = await try_else(
-		() => Deno.open(program_path, { read: true }),
-		() => fail_with("Program at", program_path, "does not exists"),
-	);
-	await try_(() => file.readable.pipeTo(connection.writable));
+async function handle(request: Request) {
+	const script = await open_requested_script(request);
+	if (script instanceof Response) return script;
+	console.log("Serving", script.path);
+	return new Response(script.content.readable);
 }
 
-function fail_with(...message: string[]) {
-	console.error(...message);
-	return Deno.exit(1);
-}
-
-async function try_else<T>(operation: () => T | Promise<T>, on_error: (error: unknown) => T | Promise<T>) {
+async function open_requested_script(request: Request) {
+	const requested_path = new URL(request.url).pathname.slice(1);
+	const invalid = () => new Response("Invalid script.", { status: 400 });
+	if (requested_path.includes("/")) return invalid();
+	if (requested_path.includes(".")) return invalid();
 	try {
-		return await operation();
-	} catch (error) {
-		return await on_error(error);
+		const path = "./scripts/" + requested_path + ".lua";
+		const content = await Deno.open(path, { read: true });
+		return { path, content };
+	} catch (_) {
+		return new Response("Unknown script.", { status: 400 });
 	}
 }
 
-async function try_<T>(operation: () => T | Promise<T>) {
-	return await try_else(operation, () => null);
-}
-
 if (import.meta.main) await main();

cc-tweaked/scripts/cat.lua

@@ -1,8 +1,17 @@
-local arg1, arg2, arg3 = ...
+local path = ...
 
 local function main()
-    print("arg1", arg1, "arg2", arg2, "arg3", arg3)
-    local file = fs.open()
+    if path == nil then
+        print("Usage: cat <path>")
+        return
+    end
+    local file = fs.open(path, "r")
+    if file == nil then
+        print("No such file:", path)
+        return
+    end
+    local content = file.readAll()
+    print(content)
 end
 
 main()