Does objection.js automatically send a 200 response?

Question

I was using mongodb and I migrated to objection and knex for some reasons, And my issue comes from this login code (back server) :

  User.query()
    .where("email", "=", req.body.email)
    .then((user) => {
      if (user.length == 0) {
        return res.json("Incorrect Email.").sendStatus(401); // If the email is not already recorded
      }

I get this error message : Error [ERR_HTTP_HEADERS_SENT]: Cannot set headers after they are sent to the client And the response I get from the front side is 200. So I think objection.js automatically sends a 200 response, even if the email is incorrect. Anyone facing the same issue ?

EDIT : The front fetch code :

  async function handleSubmit(e) {
    e.preventDefault();

    await fetch(`https://localhost:8443/api/auth/login`, {
      method: "POST",
      mode: "cors",
      credentials: "include",
      headers: {
        Accept: "application/json",
        "Content-Type": "application/json",
      },
      body: JSON.stringify({ email, password }),
    }).then((response) =>
      response
        .json()
        .then(({ data }) => {
          console.log(response);
          switch (response.status) {
            case 200:
              localStorage.setItem("xsrfToken", JSON.stringify(data.xsrfToken));
              const roles = data.roles;
              const _id = data._id;
              const accessToken = data.accessToken;
              setAuth({ _id, email, password, roles, accessToken });
              setEmail("");
              setPassword("");
              // Remove the console.log before deployment
              console.log(data);
              navigate(from, { replace: true });
              break;
            case 401:
              setErrMsg("Your Email or your password is wrong.");
              errRef.current.focus();
              // Remove the console.log before deployment
              console.log(data);
              break;
            case 500:
              setErrMsg("500");
              console.log(data);
              break;
            default:
          }
        })
        .catch((error) => {
          errRef.current.focus();
          console.log(error);
        })
    );
  }

Answer 1

I solved the problem by doing: res.status(401).json("Incorrect Email."); Instead of : res.json("Incorrect Email.").sendStatus(401); And I can't explain why this code worked very well before objection.js.

If anyone can explain it...