Firebase云函数引发“无法处理请求”错误

Question

我将以下云功能部署到Firebase，但是当用Postman测试请求时，我收到Error: could not handle the request错误。

 exports.createMemes = functions.https.onRequest((req, res) => {
        const newMeme = {
            body: req.body.body,
            userHandle: req.body.userHandle,
            createdAt: admin.firestore.Timestamp.fromDate(new Date())
        };

        admin.firestore()
            .collection('memer')
            .add(newMeme)
            .then((doc) => {
                res.json({ message: `document ${doc.id} created succesfully`});
                return null;
            }) 
            .catch((err) => {
                res.status().json({ error: 'something went wrong'});
                console.error(err);
            });
    });