I cannot download a zip file (using `send_file`) when using nginx as a proxy.

```
def download
  send_file file_path, filename: "file.zip"
end

```

Running without nginx (webrick only) it works fine but with the nginx proxy it opens this in the browser:[![enter image description here](https://i.stack.imgur.com/S5Wdf.png)](https://i.stack.imgur.com/S5Wdf.png)

Nginx proxy config:

```
server {
    server_name mydomain.com;

    location / {
        proxy_pass http://localhost:3001;
        proxy_set_header Host $host;
        auth_basic "Restricted";
        auth_basic_user_file /etc/nginx/keys/app.htpasswd;
    }
}

```

Edit:
-----

Reloading the page results in the document being downloaded, so I looked at the request headers for each request. They should both be the same, but they are not.

### Opened in browser

![Failed](https://i.stack.imgur.com/kzArp.png)

### Successfully downloaded

![Successful](https://i.stack.imgur.com/Y1pMF.png)

The only difference is that the first one I clicked a link (opening link in new tab downloads and opens the file) and I refreshed the page on the second one.

Edit 2:
-------

I tried it again with webrick and it is doing the same thing.