heroku node js create folder issue - node.js

Question

I have express app which works fine on localhost, but when I deploy it to heroku it doesn't create any folders, although all other functionality works fine
in order to specify the path to the file i use nodejs path and save it to mongoDB
How it looks on Localhost:5000 after uploading file inside project:
MongoDB file path field:
C:\Users\inbec\OneDrive\New folder\Documents\Code\servers\CooperateFront-back\files/60f063de9e95e729f05dfcfb/60f0642b9e95e729f05dfd02/60f064369e95e729f05dfd07/Screenshot_3.png
How it looks with Heroku:
Heroku CLI: heroku run bash -a cooperatefront-back
~/files $ cd 60f063de9e95e729f05dfcfb
bash: cd: 60f063de9e95e729f05dfcfb: No such file or directory
In Browser:
Cannot GET
/app/files/60f063de9e95e729f05dfcfb/60f05fe09d17a600223700d7/60f05fe59d17a600223700db/Screenshot_1.png
MongoDB file path field: /app/files/60f063de9e95e729f05dfcfb/60f05fe09d17a600223700d7/60f05fe59d17a600223700db/Screenshot_1.png
index.js
app.use(filePathMiddleWare(path.resolve(__dirname, "files")))
app.use(fileUpload({}))
app.use("/files",express.static("files"))
filepath-middleware:
function filePath(path) {
return function (req, res, next) {
req.filePath = path
next()
}
}
module.exports = filePath
FileService:
class FileService {
createDor(req,file) {
console.log(req.filePath, "filePath")
const filePath = `${req.filePath}\\${file.user}\\${file.path}`
return new Promise(((resolve, reject) => {
try {
if (!fs.existsSync(file)) {
fs.mkdirSync(filePath)
return resolve({message: "File was created"})
} else {
return reject({message: "File already exists"})
}
} catch (e) {
console.log(e)
return reject({message: "File error"})
}
}))
}
}

Answer 1

Found ussue:
no need to specify the /app folder to get file
{myHerokuSite}/files/60f06d3f41e750002225c04a/60f06d4641e750002225c051/60f06d4c41e750002225c055/photo_2021-02-22_09-33-17.jpg
and just in case changed \\ to /
const filePath = ${req.filePath}\\${file.user}\\${file.path} =>
${req.filePath}/${file.user}/${file.path}

Answer 2

I know you have already answerd your own question here but just be aware that Heroku is essentially a CASS service (container as a service)
This means ephemeral storage is not persistent. Each time you restart, redeploy all items will be lost.
A better approach would be do use an object store like S3. This will allow you to store the images on a persistent volume that will allow your application to keep working even with restarts as the code runs on the container and dynamic / user create assets will be stored in the object store and shared across all running instances.