问题
I have a node.js app on heroku and I sometimes need to write files to heroku. Do you know how to see those files? Should I delete them after I am finished using them? I do not want to use memory for no reason.
回答1:
Heroku (and other container based platforms) are different from traditional servers that you might be used to. It's worth bearing in mind that the Heroku filesystem is ephemeral - that means that any changes to the filesystem whilst the dyno is running only last until that dyno is shut down or restarted. Each dyno boots with a clean copy of the filesystem from the most recent deploy.
If you really needed to check a file on a running dyno (let's say to debug an issue with a file upload) it is possible to login using Heroku Exec https://devcenter.heroku.com/articles/exec
That said, you really shouldn't be using the filesystem for anything other than temporary files. Instead you should aim to use external services for persistent storage as described here: https://12factor.net/
For example, if you are handling file uploads you could try storing these on a service like Amazon S3.
来源：https://stackoverflow.com/questions/51775662/how-to-see-the-files-that-were-written-to-disk-from-node-js-app-hosted-on-heroku