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type RpcRequest = {  methodName: string;  params: unknown[];};
function isRpcRequest(obj: unknown): obj is RpcRequest {  return (typeof obj === "object" && obj !== null && "methodName" in obj &&    "params" in obj);}
async function doProcess<  T extends { [key: string]: (...args: unknown[]) => unknown },>(  funcs: T,  request: Request,) {  const reqJson = await request.json();
  if (!isRpcRequest(reqJson)) throw new Error();  if (!Object.keys(funcs).find((k) => k === reqJson.methodName)) {    throw new Error();  }
  return await funcs[reqJson.methodName].apply(null, reqJson.params);}
async function makeResponse(result: unknown): Promise<Response> {  return await Response.json(    {      result,    },  );}
export async function serverFunc<  T extends { [key: string]: (...args: any[]) => unknown },>(  funcs: T,  request: Request,  opts?: {    middleware: (      request: Request,      next: () => Promise<Response>,    ) => Promise<Response>;  },): Promise<Response> {  if (opts?.middleware) {    return await opts.middleware(request.clone(), async () => {      return makeResponse(await doProcess(funcs, request.clone()));    });  }
  return makeResponse(await doProcess(funcs, request.clone()));}