Public API: Clean up the server proxy.

e3ndr · Sep 21, 2023 · d0ad40d · d0ad40d
1 parent 4d4da10
commit d0ad40d
Showing 1 changed file with 25 additions and 8 deletions.
diff --git a/public-api/src/routes/server-proxy.mjs b/public-api/src/routes/server-proxy.mjs
@@ -1,17 +1,30 @@
 import { JsonResponse } from "./index.mjs";
 
+async function isValidAthenaServer(url) {
+    const response = await (await fetch(`${url.protocol}${url.hostname}/.well-known/x-athena`)).text();
+    return response.trim() == "yes";
+}
+
+function isAcceptableToProxy(response) {
+    const contentType = (response.headers.get("Content-Type") || "").split(";")[0];
+    if (!["text/plain", "application/json"].includes(contentType)) {
+        throw "You may only use this proxy to make non-media requests.";
+    }
+}
+
 export default (/** @type {import("itty-router").RouterType<import("itty-router").Route, any[]} */router) => {
 
     router.get("/server-proxy", async (request) => {
-        const searchParams = new URL(request.url).searchParams;
+        const url = new URL(new URL(request.url).searchParams.get("url"));
 
-        const url = new URL(searchParams.get("url"));
+        console.debug("Proxying request:", url);
 
         try {
             switch (url.protocol) {
                 case "http":
                 case "https": {
-                    if ((await (await fetch(`${url.protocol}${url.hostname}/.well-known/x-athena`)).text()).trim() != "yes") {
+                    if (!isValidAthenaServer(url)) {
+                        console.debug("Not a valid Athena server.");
                         return new JsonResponse({
                             data: null,
                             error: `The server url "${url.protocol}${url.hostname}" does not appear to be an Athena server.`,
@@ -22,23 +35,27 @@ export default (/** @type {import("itty-router").RouterType<import("itty-router"
                     const response = await fetch(url, {
                         headers: new Headers({
                             ...Object.fromEntries(request.headers.entries()),
-                            "X-Athena-Proxy-Limits": "NO_STREAMING"
+                            "X-Athena-Proxy": "used"
                         })
                     });
 
-                    const contentType = (response.headers.get("Content-Type") || "").split(";")[0];
-                    if (!["text/plain", "application/json"].includes(contentType)) {
+                    try {
+                        isAcceptableToProxy(response);
+                    } catch (message) {
+                        console.debug("Unacceptable to proxy:", message);
                         return new JsonResponse({
                             data: null,
-                            error: `You may only use this proxy to make non-media requests.`,
+                            error: message,
                             rel: null,
                         }, { status: 400 });
                     }
 
+                    console.debug("Success!");
                     return response;
                 }
 
                 default:
+                    console.debug("Invalid protocol.");
                     return new JsonResponse({
                         data: null,
                         error: `Unknown or unsupported protocol "${url.protocol}"`,
@@ -49,7 +66,7 @@ export default (/** @type {import("itty-router").RouterType<import("itty-router"
             console.error("Internal error:", e.toString(), e.stack);
             return new JsonResponse({
                 data: null,
-                error: `An internal error occurred whilst satisfying your request.`,
+                error: "An internal error occurred whilst satisfying your request.",
                 rel: null,
             }, { status: 500 });
         }