我是新来使用JavaScript的人，但是我正在尝试将input字符串作为json发布到需要使用用户名和密码作为标题或基本auth传递的外部api。我想输入我的用户名和密码，该用户名和密码从表单和onSumbit传递到标题，然后单击JSON发布到api端点。下面的当前代码对我来说根本不起作用。

import React from "react";

const host = "https://some-instance.net";
const APIend = host + "rest/api/issue";

function signIn(username,password,body) {
  const options = {
    method: "post",headers: new Headers({ username,password }),input: '{"fields": {"project":{"key": "TEST"},"summary": "REST ye merry gentlemen.","description": "Creating of an issue using project keys and issue type names using the REST API","issuetype": {"name": "Bug"}}}}'
  };
  options.body = JSON.stringify(body);

  fetch(APIend,options)
    .then(response => response.json())
    .then(data => console.log(data));
}

class Jissue extends React.Component {
  render() {
    return (
      <div classname="container">
        <h1>login to create issue</h1>
        <form onSubmit={signIn.post}>
          <input id="username" type="text" placeholder="username" />
          <input id="password" type="password" placeholder="password" />
          <button type="submit" classname="button">
            <span>Submit</span>
          </button>
        </form>
      </div>
    );
  }
}
export default Jissue;