React-router showing invalid hook call

Question

An invalid hook error occurred in my react app caused by react-router but I can't seem to detect where it's coming from. The full error reads as follows:

Error: Invalid hook call. Hooks can only be called inside of the body of a function component. This could happen for one of the following reasons:
1. You might have mismatching versions of React and the renderer (such as React DOM)
2. You might be breaking the Rules of Hooks
3. You might have more than one copy of React in the same app
See https://reactjs.org/link/invalid-hook-call for tips about how to debug and fix this problem.

I don't have a mismatch of React versions nor is the error caused (can't say for sure but I don't) by any of the reasons stated. I followed the react-router docs here . I know I'm messing up something but I don't know where.

Below are the necessary components, starting from the entry file.

index.js

import React from "react";
import ReactDOM from "react-dom";
import { BrowserRouter } from "react-router-dom";
import {
  ApolloProvider,
  ApolloClient,
  createHttpLink,
  InMemoryCache,
} from "@apollo/client";
import { setContext } from "@apollo/client/link/context";
import {AUTH_TOKEN} from "./constants";
import App from "./components/App";
import "./styles/index.css";

const httpLink = createHttpLink({ uri: "http://localhost:4000" });

const authLink = setContext((_, { headers }) => {
  const token = localStorage.getItem(AUTH_TOKEN);

  return {
    ...headers,
    authorization: token ? `Bearer ${token}` : "",
  };
});

/*Instantiates Apollo client and connect to GraphQL server.
This will take the server link and an instantiation of the cache funtionality*/
const client = new ApolloClient({
  link: authLink.concat(httpLink),
  cache: new InMemoryCache(),
});

ReactDOM.render(
  <BrowserRouter>
    <ApolloProvider client={client}>
      <React.StrictMode>
        <App />
      </React.StrictMode>
    </ApolloProvider>
  </BrowserRouter>,
  document.getElementById("root")
);

App.js

import React from "react";
import LinkList from "./LinkList";
import CreateLink from "./CreateLink";
import Header from "./Header";
import Login from './Login';
import { Routes, Route } from "react-router-dom";
import "../styles/App.css";

function App() {
  return (
    <div className="center w85">
      <Header />
      <div className="ph3 pv1 background-gray">
        <Routes>
          <Route path="/" element={<LinkList/>} />
          <Route path="/create" element={<CreateLink/>} />
          <Route path="/login" element={<Login/>} />
        </Routes>
      </div>
    </div>
  );
}

export default App;

Header.js

import React from "react";
import { useNavigate, Link } from "react-router-dom";
import { AUTH_TOKEN } from "../constants";

export default function Header() {
    const history = useNavigate();
    const authToken = localStorage.getItem(AUTH_TOKEN);

    return (
        <div className="flex pa1 justify-between nowrap orange">
            <div className="flex flex-fixed black">
                <div className="fw7 mr1">Hacker News</div>
                <Link to="/" className="ml1 no-underline black">
                    new
                </Link>
                <div className="ml1">|</div>
                <Link to="/top" className="ml1 no-underline black">
                    top
                </Link>
                <div className="ml1">|</div>
                <Link to="/search" className="ml1 no-underline black">
                    search
                </Link>
                {authToken && (
                    <div className="flex">
                        <div className="ml1">|</div>
                        <Link to="/create" className="ml1 no-underline black">
                            submit
                        </Link>
                    </div>
                )}
            </div>
            <div className="flex flex-fixed">
                {authToken ? (
                    <div
                        className="ml1 pointer black"
                        onClick={() => {
                            localStorage.removeItem(AUTH_TOKEN);
                            history.push(`/`);
                        }}
                    >
                        logout
                    </div>
                ) : (
                    <Link to="/login" className="ml1 no-underline black">
                        login
                    </Link>
                )}
            </div>
        </div>
    );
}

LinkList.js

import React from "react";
import { useQuery, gql } from "@apollo/client";
import Link from "./Link";

const LinkList = () => {

  const FEED_QUERY = gql`
    {
      feed {
        id
        links {
          id
          createdAt
          url
          description
        }
      }
    }
  `;

  const { loading, error, data } = useQuery(FEED_QUERY);

  if (loading) return <p style={{padding: 20, textAlign:"center"}}>Loading...</p>;

  if (error) console.log(error);

  return (
    <div>
      {data &&
        data.feed.links.map((link) => <Link key={link.id} link={link} />)}
    </div>
  );
};

export default LinkList;

CreateLink.js

import React, { useState } from "react";
import { useMutation, gql } from "@apollo/client";
import { useNavigate } from "react-router-dom";

export default function CreateLink() {
    const [formState, setFormState] = useState({ description: "", url: "" });

    const history = useNavigate();

    const CREATE_LINK_MUTATION = gql`
        mutation PostMutation($url: String!, $description: String!) {
            post(url: $url, description: $description) {
                id
                createdAt
                url
                description
            }
        }
    `;

    const [createLink] = useMutation(CREATE_LINK_MUTATION, {
        variables: {
            description: formState.description,
            url: formState.url,
        },
        onCompleted: () => history.push("/")
    });

    return (
        <div>
            <form
                onSubmit={(e) => {
                    e.preventDefault();
                    createLink();
                }}
            >
                <div className="flex flex-column mt3">
                    <input
                        type="text"
                        className="mt2"
                        placeholder="A description for the link"
                        onChange={(e) =>
                            setFormState({
                                ...formState,
                                description: e.target.value,
                            })
                        }
                        value={formState.description}
                    />
                    <input
                        className="mb2"
                        value={formState.url}
                        onChange={(e) =>
                            setFormState({
                                ...formState,
                                url: e.target.value,
                            })
                        }
                        type="text"
                        placeholder="The URL for the link"
                    />
                </div>
                <button type="submit">Submit</button>
            </form>
        </div>
    );
}

Login.js

import React, { useState } from "react";
import { useNavigate } from "react-router-dom";
import { gql, useMutation } from "@apollo/client";
import { AUTH_TOKEN } from '../constants';

export default function Login() {
    let history = useNavigate();

    const [formState, setFormState] = useState({
        login: true,
        email: "",
        password: "",
        name: "",
    });

    const SIGNUP_MUTATION = gql`
        mutation SignupMutation(
            $email: string
            $password: string
            $name: string
        ) {
            signup(email: $email, password: $password, name: $name) {
                token
                user {
                    name
                    email
                }
            }
        }
    `;

    const [signup] = useMutation(SIGNUP_MUTATION, {
        variables: {
            email: formState.email,
            password: formState.password,
            name: formState.password,
        },
        onCompleted: ({ signup }) => {
            localStorage.setItem(AUTH_TOKEN, signup.token);
            history.push("/create");
        },
    });

    const LOGIN_MUTATION = gql`
        mutation LoginMutation($email: string, $password: string) {
            login(email: $email, password: $password) {
                token
            }
        }
    `;

    const [login] = useMutation(LOGIN_MUTATION, {
        variables: {
            email: formState.email,
            password: formState.password,
        },
        onCompleted: ({ login }) => {
            localStorage.setItem(AUTH_TOKEN, signup.token);
            history.push("/");
        },
    });

    return (
        <div>
            <h4 className="mv3">{formState.login ? "Login" : "Sign Up"}</h4>
            <div className="flex flex-column">
                {!formState.login && (
                    <input
                        value={formState.name}
                        onChange={(e) =>
                            setFormState({
                                ...formState,
                                name: e.target.value,
                            })
                        }
                        type="text"
                        placeholder="Your name"
                    />
                )}
                <input
                    value={formState.email}
                    onChange={(e) =>
                        setFormState({
                            ...formState,
                            email: e.target.value,
                        })
                    }
                    type="text"
                    placeholder="Your email address"
                />
                <input
                    value={formState.password}
                    onChange={(e) =>
                        setFormState({
                            ...formState,
                            password: e.target.value,
                        })
                    }
                    type="password"
                    placeholder="Choose a safe password"
                />
            </div>
            <div className="flex mt3">
                <button
                    className="pointer mr2 button"
                    onClick={() => (formState.login ? login : signup)}
                >
                    {formState.login ? "login" : "create account"}
                </button>
                <button
                    className="pointer button"
                    onClick={(e) =>
                        setFormState({
                            ...formState,
                            login: !formState.login,
                        })
                    }
                >
                    {formState.login
                        ? "need to create an account?"
                        : "already have an account?"}
                </button>
            </div>
        </div>
    );
}

Installed version of React according to packages in project:

react-apollo-integration@0.1.0 c:\projects\react-apollo-integration\frontend
+-- @apollo/client@3.4.17
| `-- react@17.0.2 deduped
+-- @testing-library/react@11.2.7
| +-- react-dom@17.0.2 deduped
| `-- react@17.0.2 deduped
+-- react-dom@17.0.2
| `-- react@17.0.2 deduped
+-- react-scripts@4.0.3
| `-- react@17.0.2 deduped
`-- react@17.0.2

Answer 1

It looks like you are missing the router and a switch.

 import React from "react"; import LinkList from "./LinkList"; import CreateLink from "./CreateLink"; import Header from "./Header"; import Login from './Login'; import { BrowserRouter as Router, Route, Switch } from "react-router-dom"; import "../styles/App.css"; function App() { return ( <div className="center w85"> <Header /> <div className="ph3 pv1 background-gray"> <Router> <Switch> <Route path="/" element={<LinkList/>} /> <Route path="/create" element={<CreateLink/>} /> <Route path="/login" element={<Login/>} /> </Switch> </Router> </div> </div> ); } export default App;

Answer 2

I found out what I did wrong. I installed the react-router package outside the project's directory. My bad!

Answer 3

I deleted the npm modules and the Json file but it keeps installing back whenever I install react-router-dom which makes keep saying invalid hook...