SPA構成の通信がステートレスかどうかがわからない

import { client } from "./client";
import Cookies from "js-cookie";

// サインアップ
export const signUp = (params) => {
 return client.post("/auth", params);
};

// サインイン
export const signIn = (params) => {
 return client.post("/auth/sign_in", params);
};

// サインアウト
export const signOut = () => {
 return client.delete("/auth/sign_out", {
  headers: {
   "access-token": Cookies.get("_access_token"),
   client: Cookies.get("_client"),
   uid: Cookies.get("_uid"),
  },
 });
};

// Cookieに必要なデータセットがあるかを確認。揃っていればrailsに投げてcurrentUserがいるかを検索。
export const getCurrentUser = () => {
 if (
  !Cookies.get("_access_token") ||
  !Cookies.get("_client") ||
  !Cookies.get("_uid")
 )
  return console.log("ログイン中のユーザーはいません。");
 return (
  client.get("/auth/sessions", {
   headers: {
    "access-token": Cookies.get("_access_token"),
    "client": Cookies.get("_client"),
    "uid": Cookies.get("_uid"),
   },
  })
 )
};

import { createContext, useEffect, useState } from "react";
import { BrowserRouter, Switch, Route, Redirect } from "react-router-dom";
import { getCurrentUser } from "./api/auth";
import { Home } from "./components/Home";
import { SignIn } from "./components/SignIn";
import { SignUp } from "./components/SignUp";
import { Top } from "./components/Top";

export const AuthContext = createContext();

function App() {
  const [loading, setLoading] = useState(true);
  const [isSignedIn, setIsSignedIn] = useState(false);
  const [currentUser, setCurrentUser] = useState();

  // Cookieからログイン中ユーザーを取得、結果をハンドリング
  const handleGetCurrentUser = async () => {
    try {
      const res = await getCurrentUser();
      if (res?.status === 200) {
        setIsSignedIn(true);
        setCurrentUser(res?.data.currentUser);
        console.log(res?.data.currentUser);
      } else {
        console.log("no current user");
      }
    } catch (e) {
      console.log(e);
    }
    setLoading(false);
  };

  useEffect(() => {
    handleGetCurrentUser();
  }, [setCurrentUser]);

  const Private = ({ children }) => {
    if (!loading) {
      if (isSignedIn) {
        return children;
      } else {
        return <Redirect to="/signin" />;
      }
    } else {
      return <></>;
    }
  };
  return (
    <AuthContext.Provider
      value={{
        loading,
        setLoading,
        isSignedIn,
        setIsSignedIn,
        currentUser,
        setCurrentUser,
      }}
    >
      <BrowserRouter>
        <Switch>
          <Route exact path="/top">
            <Top />
          </Route>
          <Route exact path="/signin">
            <SignIn />
          </Route>
          <Private>
            <Route exact path="/">
              <Home />
            </Route>
          </Private>
        </Switch>
      </BrowserRouter>
    </AuthContext.Provider>
  );
}

export default App;

class Api::V1::Auth::SessionsController < ApplicationController

 def index
     if current_api_v1_user
         render json: {status:200, current_user: current_api_v1_user }
     else
         render json: {status: 500, message: "ユーザーが存在しません"}
     end
 end
end