Always convert petName to image hash in loadCustomPetData

src/server/load-pet-data.js

@@ -0,0 +1,128 @@
+import fetch from "node-fetch";
+
+async function neopetsAmfphpCall(methodName, args) {
+  const url =
+    "https://www.neopets.com/amfphp/json.php/" +
+    encodeURIComponent(methodName) +
+    "/" +
+    args.map(encodeURIComponent).join("/");
+
+  const res = await fetch(url, {
+    headers: {
+      "X-Requested-With": "XMLHttpRequest",
+      "User-Agent": "impress-2020 (https://impress-2020.openneo.net/)",
+    },
+  });
+  if (!res.ok) {
+    throw new Error(
+      `[AMFPHP] HTTP request failed, got status ${res.status} ${res.statusText}`,
+    );
+  }
+
+  return res.json();
+}
+
+export async function loadPetMetaData(petName) {
+  return neopetsAmfphpCall("PetService.getPet", [petName]);
+}
+
+export async function loadCustomPetData(petName) {
+  // HACK: The json.php amfphp endpoint is known not to support string
+  // arguments with leading digits. (It aggressively parses them as ints lmao.)
+  // So, we work around it by converting the pet name to its image hash, then
+  // prepending "@", which is a special code that can *also* be used in the
+  // CustomPetService in place of name, to get a pet's appearance from its image
+  // hash.
+  const imageHash = await loadImageHashFromPetName(petName);
+  console.debug(
+    `[loadCustomPetData] Converted pet name ${petName} to @${imageHash}`,
+  );
+  petName = "@" + imageHash;
+
+  try {
+    return neopetsAmfphpCall("CustomPetService.getViewerData", [petName]);
+  } catch (error) {
+    // If Neopets.com fails to find valid customization data, we return null.
+    if (
+      error.code === "AMFPHP_RUNTIME_ERROR" &&
+      error.faultString === "Unable to find body artwork for this combination."
+    ) {
+      return null;
+    } else {
+      throw error;
+    }
+  }
+}
+
+const PETS_CP_URL_PATTERN =
+  /https?:\/\/pets\.neopets\.com\/cp\/([a-z0-9]+)\/[0-9]+\/[0-9]+\.png/;
+async function loadImageHashFromPetName(petName) {
+  const res = await fetch(`https://pets.neopets.com/cpn/${petName}/1/1.png`, {
+    redirect: "manual",
+  });
+  if (res.status !== 302) {
+    throw new Error(
+      `[loadImageHashFromPetName] expected /cpn/ URL to redirect with status ` +
+        `302, but instead got status ${res.status} ${res.statusText}`,
+    );
+  }
+
+  const newUrl = res.headers.get("location");
+  const newUrlMatch = newUrl.match(PETS_CP_URL_PATTERN);
+  if (newUrlMatch == null) {
+    throw new Error(
+      `[loadImageHashFromPetName] expected /cpn/ URL to redirect to a /cp/ ` +
+        `URL matching ${PETS_CP_URL_PATTERN}, but got ${newUrl}`,
+    );
+  }
+
+  return newUrlMatch[1];
+}
+
+export async function loadNCMallPreviewImageHash(basicImageHash, itemIds) {
+  const query = new URLSearchParams();
+  query.append("selPetsci", basicImageHash);
+  for (const itemId of itemIds) {
+    query.append("itemsList[]", itemId);
+  }
+
+  // When we get rate limited, subsequent requests to the *exact* same URL
+  // fail. For our use case, it makes sense to cache-bust that, I think!
+  query.append("dti-rand", Math.random());
+
+  const url = `http://ncmall.neopets.com/mall/ajax/petview/getPetData.php?${query}`;
+  const res = await fetch(url);
+  if (!res.ok) {
+    try {
+      console.error(
+        `[loadNCMallPreviewImageHash] ${res.status} ${res.statusText}:\n` +
+          (await res.text()),
+      );
+    } catch (error) {
+      console.error(
+        `[loadNCMallPreviewImageHash] could not load response text for ` +
+          `NC Mall preview failed request: ${error.message}`,
+      );
+    }
+    throw new Error(
+      `could not load NC Mall preview image hash: ${res.status} ${res.statusText}`,
+    );
+  }
+
+  const dataText = await res.text();
+  if (dataText.includes("trying to reload the page too quickly")) {
+    throw new Error(`hit the NC Mall rate limit`);
+  }
+  const data = JSON.parse(dataText);
+  if (data.success !== true) {
+    throw new Error(
+      `NC Mall preview returned non-success data: ${JSON.stringify(data)}`,
+    );
+  }
+  if (!data.newsci) {
+    throw new Error(
+      `NC Mall preview returned no newsci field: ${JSON.stringify(data)}`,
+    );
+  }
+  return data.newsci;
+}