错误记录（12）：No 'Access-Control-Allow-Origin' header is present on the requested resource.

背景

使用Python微框架flask写接口时，请求某个方法需要返回一些json数据。本机没有任何问题，当需要前后端分离时，做内网穿透，其他机子请求这个接口会报错，错误提示：

Failed to load http://192.xxxx/api: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://192.xxxx' is therefore not allowed access.

报错代码：

@app.route('/show_person', methods=['GET', 'POST'])
def show_person():
    all_person_dict = person_dict.person()
    all_person_json = json.dumps(all_person_dict)
    resp = jsonify({'person': all_person_json})
    return resp

解决方法：

按照错误提示，需要在请求头加入：Access-Control-Allow-Origin

正确代码：

@app.route('/show_person', methods=['GET', 'POST'])
def show_person():
    all_person_dict = person_dict.person()
    all_person_json = json.dumps(all_person_dict)
    resp = jsonify({'person': all_person_json})
    resp.headers['Access-Control-Allow-Origin'] = '*'
    return resp