Uploader API Demo

Introduction

Write a program that provides an HTTP API to store and retrieve files. It should support the following features:

• Upload a new file
• Retrieve an uploaded file by name
• Delete an uploaded file by name
• Include a NixOS module to provide the API as a service
• If multiple files have similar contents, reuse the contents somehow to save space.

Requirement

• GHC 8.2.2
• Nix
• SQLite (for store file metadata)
• NixOps (for deployment)

Local Development

Run nix-build then run execute file

nix-build ./release.nix
./result/bin/file-api

Server will run at http://localhost:3000. If you want to use another port, set PORT environment

Use as module

Import /path/to/uploader-demo/fileapi.nix to configuration.nix file and enable service with options

  imports = [
    ...
    /path/to/uploader-demo/fileapi.nix
  ];


  services = {
    fileAPI = {
      enable = true;
      dbPath = "/tmp/fileapi/db";
      dbName = "file.db";
      uploadDirectory = "/tmp/fileapi/uploads";
      port = 3000;
    };
  };

Deployment

Use NixOps to deploy Support targets:

• NixOS machines: release-nixos.nix
• Virtualbox: release-vbox.nix
• AWS EC2: release-ec2.nix

nixops create ./release-configuration.nix ./release-vbox.nix -d fileapi
nixops deploy -d fileapi --option system "x86_64-linux"

Default directory for database and file storage is /tmp. Default port is 3000. You can change the config in release-configuration.nix file

Reuse similar content

Store file metadata in Database and content in hard disk. If file content is same, just insert a record with path uri point to absolute path in hard disk without writing file. It is same as a shortcut/link file

API Documentation

Upload File (can upload many files)

URL : /uploads/

Method : POST

Content-Type: multipart/form-data

Auth required : NO

Success Response

Code : 200 OK

Content example

[{
    "name": "file.jpg",
    "type": "image/jpeg",
    "size": 300000,
    "uri": "uploads/file.jpg",
    "isLink": 0 // 0: Physic file, 1: Shortcut file
}]

Direct Upload

URL : /upload-direct

Method : POST

Content-Type: image/jpeg (Depend on file's MIME type)

Auth required : NO

Success Response

Code : 200 OK

Content example

[{
    "name": "file.jpg",
    "type": "image/jpeg",
    "size": 300000,
    "uri": "uploads/file.jpg",
    "isLink": 0 // 0: Physic file, 1: Shortcut file
}]

Error Response

Condition : X-File-Name or Content-Type header is empty

Code : 400 BAD REQUEST

Content :

{
    "message": "X-File-Name is required"
}

GET file by name

URL : /uploads/:name

Method : GET

Auth required : NO

Success Response

Code : 200 OK

Content : File content

Error Response

Condition : File not found

Code : 404 NOT FOUND

Content :

{
    "message": "File not found"
}

DELETE file by name

URL : /uploads/:name{?force=1}

Method : DELETE

Query Parameter:

• name (string): File name
• force (string): Forced delete

Auth required : NO

Success Response

Code : 204 NO CONTENT

Error Response

Condition : File not found

Code : 404 NOT FOUND

Content :

{
    "message": "File not found"
}