Node.js Heroku上的svg2png-类型错误：错误参数

我对Heroku上的SVG2NG包有问题。它可以在我的本地机器（Windows）上运行，但我无法让它在免费dyno和付费dyno（嗜好和标准x1）上运行

其想法是从维基百科获取svg并将其作为png返回。我已经公开了两个端点：

• /-使用存储在单独文件中的代码
• /简单-相同的代码，但只是在回调中

浏览两个端点时，我会收到Heroku应用程序错误页面。这就是我在Heroku日志中看到的两个请求：

Bad argument TypeError: Bad argument
 at exports.spawn (child_process.js:378:9)
 at Object.execFile (/app/node_modules/pn/_promisify.js:35:27)
 at TypeError (native)
 at ChildProcess.spawn (internal/child_process.js:294:26)
 at Object.exports.execFile (child_process.js:143:15)
 at Promise.resolve.then (/app/node_modules/svg2png/lib/svg2png.js:13:33)
 at process._tickCallback (internal/process/next_tick.js:109:7)

你有什么想法吗

index.js

const svg2png = require('svg2png')
const axios = require('axios')
const express = require('express')
const bodyParser = require('body-parser')
const conv = require('./conv')

const svgUrl = 'https://upload.wikimedia.org/wikipedia/commons/0/02/SVG_logo.svg'

const app = express()

app.use(bodyParser.json({limit:'5mb'}))
app.use(bodyParser.urlencoded({extended:true,limit:'5mb'}))

app.get('/simple', function (req, res) {
    axios.get(svgUrl)
        .then(response => {
            return svg2png(response.data, { width: 150, height: 150 })
        })
        .then(pngFile => {
            var img = new Buffer(pngFile, 'base64')
            res.writeHead(200, {
                'Content-Type': 'image/png',
     'Content-Length': img.length
            })
            res.end(img)
        })
})

app.get('/', function (req, res) {
conv.send()    
        .then(pngFile => {
            var img = new Buffer(pngFile, 'base64')
            res.writeHead(200, {
                'Content-Type': 'image/png',
     'Content-Length': img.length
            })
            res.end(img)
        })
})

app.listen(process.env.PORT || 5000, function () {
    console.log('Application started')
})

const axios = require('axios')
const svg2png = require('svg2png')

module.exports = {
    send() {
        const self = this;
                self.width = 300;
        self.height = 300;

        const svgUrl = 'https://upload.wikimedia.org/wikipedia/commons/0/02/SVG_logo.svg'
        return new Promise((resolve, reject) => {
            axios.get(svgUrl)
            .then(response => 

            svg2png(response.data,
             { width: self.width, height: self.height })
            .then(img=>resolve(img))
            .catch(e => {
                console.log('Something went wrong during svg2png conversion.' + e)
                reject(e)
            }))
        });

    }
}

conv.js

const svg2png = require('svg2png')
const axios = require('axios')
const express = require('express')
const bodyParser = require('body-parser')
const conv = require('./conv')

const svgUrl = 'https://upload.wikimedia.org/wikipedia/commons/0/02/SVG_logo.svg'

const app = express()

app.use(bodyParser.json({limit:'5mb'}))
app.use(bodyParser.urlencoded({extended:true,limit:'5mb'}))

app.get('/simple', function (req, res) {
    axios.get(svgUrl)
        .then(response => {
            return svg2png(response.data, { width: 150, height: 150 })
        })
        .then(pngFile => {
            var img = new Buffer(pngFile, 'base64')
            res.writeHead(200, {
                'Content-Type': 'image/png',
     'Content-Length': img.length
            })
            res.end(img)
        })
})

app.get('/', function (req, res) {
conv.send()    
        .then(pngFile => {
            var img = new Buffer(pngFile, 'base64')
            res.writeHead(200, {
                'Content-Type': 'image/png',
     'Content-Length': img.length
            })
            res.end(img)
        })
})

app.listen(process.env.PORT || 5000, function () {
    console.log('Application started')
})

const axios = require('axios')
const svg2png = require('svg2png')

module.exports = {
    send() {
        const self = this;
                self.width = 300;
        self.height = 300;

        const svgUrl = 'https://upload.wikimedia.org/wikipedia/commons/0/02/SVG_logo.svg'
        return new Promise((resolve, reject) => {
            axios.get(svgUrl)
            .then(response => 

            svg2png(response.data,
             { width: self.width, height: self.height })
            .then(img=>resolve(img))
            .catch(e => {
                console.log('Something went wrong during svg2png conversion.' + e)
                reject(e)
            }))
        });

    }
}

---

Heroku日志是否有关于哪一行可能导致

类型错误的更多信息？这将使追踪问题所在变得更容易。@bouteillebleu，我已经更新了帖子，粘贴了完整的错误消息。当我使用catch（）方法进行日志记录时，我发现问题出在svg2png中（假设我正确地链接了promise方法…）。