import requests
import json


def get_wechat_token(appid, appsecret):
    """
    通过微信公众号的APPID和AppSecret获取access_token

    参数:
        appid (str): 公众号的APPID
        appsecret (str): 公众号的AppSecret

    返回:
        str: 成功时返回access_token
        None: 失败时返回None
    """
    if not appid or not appsecret:
        return None

    # 微信获取token的接口
    url = f"https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid={appid}&secret={appsecret}"

    try:
        # 发送GET请求
        response = requests.get(url, timeout=10)
        # 解析JSON响应
        result = json.loads(response.text)

        # 检查是否返回了错误信息
        if "errcode" in result and result["errcode"] != 0:
            return None

        # 返回获取到的token
        return result.get("access_token")

    except requests.exceptions.RequestException:
        return None
    except json.JSONDecodeError:
        return None