init

rpcChecker.ts

@@ -0,0 +1,75 @@
+import axios from "axios";
+import mainnet from "chain-registry/mainnet";
+import testnet from "chain-registry/testnet";
+import fs from "fs";
+import path from "path";
+
+export type RpcResult = {
+  chain: string;
+  url: string;
+  latency: number | null;
+  status: "OK" | "ERROR" | "FAIL";
+  message?: string;
+};
+
+export type RpcCache = Record<string, RpcResult[]>;
+
+const CACHE_FILE = path.join(__dirname, "cache.json");
+
+function saveCacheToFile(cache: RpcCache) {
+  fs.writeFileSync(CACHE_FILE, JSON.stringify(cache, null, 2), "utf-8");
+}
+
+async function checkRpcLatency(chain: string, url: string): Promise<RpcResult> {
+  const start = Date.now();
+  try {
+    const response = await axios.get(`${url}/status`, { timeout: 5000 });
+    const latency = Date.now() - start;
+    if (response.status === 200) {
+      return { chain, url, latency, status: "OK" };
+    } else {
+      return {
+        chain,
+        url,
+        latency,
+        status: "ERROR",
+        message: `Status code ${response.status}`,
+      };
+    }
+  } catch (error: any) {
+    return { chain, url, latency: null, status: "FAIL", message: error.message };
+  }
+}
+
+export async function generateRpcCache(updateCallback?: (chain: string, result: RpcResult[]) => void): Promise<RpcCache> {
+  const results: RpcCache = {};
+
+  const chains = [...mainnet.chains, ...testnet.chains];
+
+  for (const chain of chains) {
+    const chainName = chain.chainName;
+    const rpcs = chain.apis?.rpc?.map((rpc) => rpc.address) || [];
+    
+    const chainResults: RpcResult[] = [];
+
+    for (const url of rpcs) {
+      const res = await checkRpcLatency(chainName, url);
+      chainResults.push(res);
+    }
+
+    chainResults.sort((a, b) => {
+      if (a.latency === null) return 1;
+      if (b.latency === null) return -1;
+      return a.latency - b.latency;
+    });
+
+    results[chainName] = chainResults;
+
+    if (updateCallback) {
+      updateCallback(chainName, chainResults);
+    }
+    saveCacheToFile(results);
+  }
+
+  return results;
+}