NodeJS/Express - Cannot Read All Req.Headers

Question

Building a simple ToDo app with ReactJs frontend and NodeJs/Express backend. I configured my frontend to include userId as a request header:

export default function authHeader() {
    const user = JSON.parse(localStorage.getItem('user'));
  
    if (user && user.accessToken) {
      // return { Authorization: 'Bearer ' + user.accessToken }; // for Spring Boot back-end
      return {
          'x-access-token': user.accessToken,
          'userid': user.id
      };       // for Node.js Express back-end
    } else {
      return {};
    }
  }

This header is included with the Axios request:

// List all Group Members
listMembers() {
    return http.get(`/group`, { headers: authHeader() });
}

Consequently, I can see the headers in the request:

Part of my auth middleware references the access token:

verifyToken = (req, res, next) => {
  let token = req.headers["x-access-token"];

  if (!token) {
    return res.status(403).send({
      message: "No token provided!"
    });
  }

  jwt.verify(token, config.secret, (err, decoded) => {
    if (err) {
      return res.status(401).send({
        message: "Unauthorized!"
      });
    }
    req.userId = decoded.id;
    next();
  });
};

The req.headers lines near the top is able to pull the token from header "x-access-token" with no problem. HOWEVER - for debug purposes, I have tried to pull the header userId value instead using let token = req.headers["userid"]; but this simply comes back as undefined in my debug tools. Why can it pull x-access token header but not userId? My eventual goal is to refer to the req.header userId value in backend SQL queries, this is just a test.

Answer 1

It ended being a capitalization error somewhere in pipeline. @Sardar's comment was on the money, make sure everything is spelled correctly and matches case.