如何修复节点中的“无法读取未定义的属性‘修剪’”错误

Question

我正在使用 TypeScript 的 express 在 Firebase 云函数中实现一个简单的 WebAPI。我的代码如下。

import * as functions from 'firebase-functions';

import * as express from 'express';

const app = express()

app.post('/', (req, res) => {

    var resText: string = "NotEmpty"

    const text: string = req.body.text

    if (isEmpty(text)) {

        resText = "Empty"

    }

    console.log("text: ", text)

    console.log("resText: ", resText)

    res.send("Echo " + resText)

})

exports.api = functions.https.onRequest(app)

const isEmpty = (str: string): boolean => {

    console.log("str: ", str, "+++")

    const trimedStr = str.trim()

    const result = (trimedStr === null || trimedStr === "")

    console.log("result: ", result)

    return result

}

构建以将打字稿转换为 javascript 工作正常。但是，当我执行 POST 方法时，发生了以下错误。

>  TypeError: Cannot read property 'trim' of undefined

>      at isEmpty (/Users/kenny/Test/firebase_functions/functions/lib/index.js:22:27)

>      at app.post (/Users/kenny/Test/firebase_functions/functions/lib/index.js:9:9)

>      at Layer.handle [as handle_request] (/Users/kenny/Test/firebase_functions/functions/node_modules/expr

ess/lib/router/layer.js:95:5)

>      at next (/Users/kenny/Test/firebase_functions/functions/node_modules/express/lib/router/route.js:137:

13)

>      at Route.dispatch (/Users/kenny/Test/firebase_functions/functions/node_modules/express/lib/router/rou

te.js:112:3)

>      at Layer.handle [as handle_request] (/Users/kenny/Test/firebase_functions/functions/node_modules/expr

ess/lib/router/layer.js:95:5)

>      at /Users/kenny/Test/firebase_functions/functions/node_modules/express/lib/router/index.js:281:22

>      at Function.process_params (/Users/kenny/Test/firebase_functions/functions/node_modules/express/lib/r

outer/index.js:335:12)

>      at next (/Users/kenny/Test/firebase_functions/functions/node_modules/express/lib/router/index.js:275:

10)

>      at expressInit (/Users/kenny/Test/firebase_functions/functions/node_modules/express/lib/middleware/in

it.js:40:5)

我该如何解决这个错误？