*refactor handling of requests and responses

*Ensure consensus query args are handled correctly

src/index.ts

@@ -1,22 +1,29 @@
 import type { Plugin, PluginAPI } from "@lumeweb/interface-relay";
 import fetch, { Request, RequestInit } from "node-fetch";
 
+import { URL } from "url";
+
 const EXECUTION_RPC_URL =
   "https://g.w.lavanet.xyz:443/gateway/eth/rpc-http/f195d68175eb091ec1f71d00f8952b85";
 
 const CONSENSUS_RPC_URL = "https://www.lightclientdata.org";
 
 async function doFetch(url: string, request: RequestInit) {
-  sanitizeRequestArgs(request);
+  sanitizeRequestArgs(url, request);
 
-  let req = new Request(url, request);
+  let req = new Request(url, {
+    ...request,
+    headers: {
+      "Content-Type": "application/json",
+    },
+  });
 
   const resp = await fetch(req);
 
   return (await resp.json()) as any;
 }
 
-function sanitizeRequestArgs(request: RequestInit) {
+function sanitizeRequestArgs(url: string, request: RequestInit) {
   if (!request || typeof request !== "object") {
     throw Error("invalid request");
   }
@@ -40,20 +47,38 @@ function sanitizeRequestArgs(request: RequestInit) {
   });
 }
 
+interface ConsensusRequest extends RequestInit {
+  path: string;
+}
+interface ExecutionRequest {
+  method: string;
+  params: string;
+}
+
 const plugin: Plugin = {
   name: "eth",
   async plugin(api: PluginAPI): Promise<void> {
-    api.registerMethod("execution_request", {
-      cacheable: false,
-      async handler(request: RequestInit): Promise<object> {
-        return doFetch(EXECUTION_RPC_URL, request);
-      },
-    });
-
     api.registerMethod("consensus_request", {
       cacheable: false,
-      async handler(request: RequestInit): Promise<object> {
+      async handler(request: ConsensusRequest): Promise<object> {
-        return doFetch(CONSENSUS_RPC_URL, request);
+        const consensusUrl = new URL(CONSENSUS_RPC_URL);
+
+        let dummyUrl = new URL(
+          `http://dummy/${request.path.replace(/^\/+/, "")}`
+        );
+        consensusUrl.pathname = dummyUrl.pathname;
+        consensusUrl.search = dummyUrl.search;
+
+        return doFetch(consensusUrl.toString(), request);
+      },
+    });
+    api.registerMethod("execution_request", {
+      cacheable: false,
+      async handler(request: ExecutionRequest): Promise<object> {
+        return doFetch(EXECUTION_RPC_URL, {
+          method: "POST",
+          body: JSON.stringify(request),
+        });
       },
     });
   },