How to write file response?

[Bobby19]

Hi guys, i found an example with file upload. But i have no idea how to implement file download.

I want to check some request in my app.lua script and if user has enough rights answer with binary data. These files might be very big, around 100Mb.

Thank you.

[leafo]

responses served from lapis are buffered in memory before being sent the client, so serving large files in lapis isn't a good idea since each request would take that much memory. Where are you serving the file from? Is it on your local disk?

I recommend letting nginx serve the file, and you can use Lua to restrict access to that endpoint. You can create a new location in your nginx config and then use one of the _by_lua directives.

[Bobby19]

Yep, these files are on my local disk. /data/www/file_storage/

Yes, i think it is a good idea to let nginx serving these files. I am going to write something like:

      content_by_lua '
        local my_module = require("my_module")
        local full_file_path = my_module.get_file_path(username, file_guid) --get_file_path will check the username and find file in db.
      ';

And then, i need somehow ask nginx to use this file as response. I know that this question is not about lapis, at all. But, could you share a link which describes such technic? And, i don't want to make these file links static in order to avoid unauthorized downloads. Please. I am newbie, so i can spend a few days searching for such manual :)

Thank you!