private RestRequest getRestRequest(String datanode) throws Exception {
    String[] parts = datanode.split(":");
    JSONObject data = new JSONObject();
    data.put(MockRestRequest.REST_METHOD_KEY, RestMethod.GET.name());
    data.put(MockRestRequest.URI_KEY,
        Operations.GET_PEERS + "?" + GetPeersHandler.NAME_QUERY_PARAM + "=" + parts[0] + "&"
            + GetPeersHandler.PORT_QUERY_PARAM + "=" + parts[1]);
    return new MockRestRequest(data, null);
  }
Get a {@link RestRequest} that requests for the peers of the given {@code datanode}
@param datanode the name of the datanode (host:port) whose peers are required.
@return a {@link RestRequest} that requests for the peers of the given {@code datanode}
@throws Exception
ambry-frontend/src/test/java/com/github/ambry/frontend/GetPeersHandlerTest.java