Notes

• Typescript is used.
• The solution uses in-memory storage for files and rate limit information (but it has the proper abstraction, so adding persistent storage should be trivial), as a consequence restarting the app will lose the data.
• It does not handle any error, it might become an issue if any of the add/delete operation fails in actual storage and file records.
• It does not restrict concurrent request from the same ip address that exceeds the daily limit for uploads and downloads.
• The garbage collector process is suboptimal, in real life it is supposed to be a separate process.
• There are few more configuration values apart from requirements which reads from environment variables or fallbacks to default value which can be changed in ./src/config.ts file. It is important to change the bucket name when using the GCP as storage provider.
• A postman collection ./file-server-api.postman_collection.json has been also added which needs to be imported in postman, Only the file needs to be selected in upload, rest of the requests are automated.
• AWS S3 and Azure Blob support has been also added.
• Open-API added the ui can be accessed in /.