调用Google Apps Script POST请求报错：CORS及doGet未找到问题排查

报错情况 #

1. Expo Web应用控制台报错：

Access to fetch at 'https://script.google.com/macros/s/_MyScriptID/exec' from origin 'http://localhost:8081' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.

2. 直接访问该Google Apps Script链接时，页面提示：

Script function not found: doGet

个人判断 #

我认为CORS策略并非问题根源，因为之前使用Google Apps Script Web应用时，只要脚本出错就会出现相同的CORS拦截报错。

相关代码 #

Expo Web的POST请求代码 #

const res = await fetch(process.env.EXPO_PUBLIC_SHEETSURL, {
    method: "POST",
    headers: {
      "Content-Type": "application/json",
    },
    
    body: JSON.stringify({
      'firstname': firstname,
      'lastname': lastname,
    })
    
  })
  
  const output = await res.text()
  console.log(output)

Google Apps Script代码 #

function doPost(e) {
  return ContentService.createTextOutput("Hello World!")
}

内容的提问来源于stack exchange，提问作者Brian Buslon