chore: simplify ext -> content type mapping code (#1368)

www/routes/raw.ts

@@ -2,9 +2,20 @@ import { RouteConfig } from "$fresh/server.ts";
 import { MultiHandler } from "$fresh/server.ts";
 import { parse } from "$std/semver/mod.ts";
 import VERSIONS from "../../versions.json" assert { type: "json" };
+import { extname } from "$std/path/mod.ts";
 
 const BASE_URL = "https://raw.githubusercontent.com/denoland/fresh/";
 
+const contentTypes = new Map([
+ [".html", "text/plain"],
+ [".ts", "application/typescript"],
+ [".js", "application/javascript"],
+ [".tsx", "text/tsx"],
+ [".jsx", "text/jsx"],
+ [".json", "application/json"],
+ [".wasm", "application/wasm"],
+]);
+
 export const handler: MultiHandler = {
  async GET(req, ctx) {
  const accept = req.headers.get("Accept");
@@ -37,23 +48,11 @@ export const handler: MultiHandler = {
  return response;
  }
 
- if (isHTML) {
- response.headers.set("Content-Type", "text/plain");
- } else if (path.endsWith(".ts")) {
- response.headers.set("Content-Type", "application/typescript");
- } else if (path.endsWith(".js")) {
- response.headers.set("Content-Type", "application/javascript");
- } else if (path.endsWith(".tsx")) {
- response.headers.set("Content-Type", "text/tsx");
- } else if (path.endsWith(".jsx")) {
- response.headers.set("Content-Type", "text/jsx");
- } else if (path.endsWith(".json")) {
- response.headers.set("Content-Type", "application/json");
- } else if (path.endsWith(".wasm")) {
- response.headers.set("Content-Type", "application/wasm");
- } else {
- response.headers.set("Content-Type", "text/plain");
- }
+ const value = isHTML
+ ? "text/plain"
+ : contentTypes.get(extname(path)) ?? "text/plain";
+ response.headers.set("Content-Type", value);
+
  return response;
  },
 };