from django.core.files.storage import Storage
import requests

class HTTPStorage(Storage):

    def __init__(self, protocol='https'):
        self.protocol = protocol

    def _open(self, name, mode='rb'):
        if mode != 'rb':
            raise IOError("Mode must be 'rb'")

        r = requests.get(self.url(name), stream=True)
        r.raise_for_status()

        return r.raw

    def _save(self, name, content):
        raise NotImplementedError("Unable to save to web locations")

    def url(self, name):
        return f"{self.protocol}:{name}"

    def exists(self, name):
        r = requests.head(self.url(name))
        return r.status_code == 200