How to set up regular updates of your NordVPN proxy for qBittorrent

You can use the qBittorrent Web API to update your VPN host recommended servers regularly. I’m using NordVPN because that’s the one I use and they specifically list recommended servers for P2P Servers using the SOCKS5 protocol on their website.

These instructions assume you have:

  • Installed HTTPie

    It’s a modern curl replacement with some nifty features. Most of which we won’t be using so you can achieve all of this stuff just as easily with curl.

  • Installed jq

    It’s a super lightweight JSON tool that allows simple parsing and output manipulation.

  • Installed and configured qBittorrent 4.1.x to run on your local machine and provide the WebUI functionality.

  • A NordVPN Account

  • Configured qBittorrent to use a VPN proxy server (this includes putting your credentials) into the config file.

Getting the server info

First we need to find out what the VPN provider recommends us to use. You can use the same server for a long time but you can get better performance by connecting to the recommended servers because those are (I guess) selected by utilization.

You will go to the Recommended Servers page. When you monitor the requests from the website while making settings you will find that for our desired settings (Germany, P2P, SOCKS5) a request like this is made:

$QUERY
https://nordvpn.com/wp-admin/admin-ajax.php\?action\=servers_recommendations\&filters\=\{"country_id":81,"servers_groups":\[15\],"servers_technologies":\[7\]\}

When you grab this with HTTPie/cURL you will get a long-ish JSON file with descriptions for the five fastest servers. We only care about the first one because that is the fastest.

Filter the output using jq to reduce the results to the raw hostname of the first entry.

http $QUERY | jq -r '.[0] | .hostname'

The result is something like de123.nordvpn.com that is the string we need to use to update the qBittorrent configuration.

Updating qBittorrent Settings

Replace the port 8112 with the port you configured for your WebUI. NOTE: :8112 is HTTPie shorthand notation for localhost:8112

Now that we know the hostname, it’s easy to regularly check for it with a cronjob and just update the configuration. To do so, you must authenticate against the API using your WebUI credentials. Those are configured in the WebUI and you should now which username/password you have there.

qBittorrent Web API uses cookies to authenticate. You need to retrieve a cookie for your user and pass that with the operations you wish to perform. For that we log in via a REST request and receive a cookie in return. After we’re done we’ll use that cookie to log out again.

Replace username:password with your credentials.

http :8112/api/v2/auth/login Referer:http://localhost:8112 -a 'username:password' -h

We can filter for the cookies string by using grep to filter for the right line containing (SessionID / SID) and then printing the second column with awk.

http :8112/api/v2/auth/login Referer:http://localhost:8112 -a 'username:password' -h  | grep SID | awk '{print $2}'

The result looks like:

SID=PAg8Sdt2FGtatFurptVXD8VGN913fNAq;

To verify which proxy is currently set you can run:

http :8112/api/v2/app/preferences 'Cookie:$COOKIE' | jq '.' | jq -r '.proxy_ip'

Now it’s time to update the configuration. For that we will POST a JSON payload to the API containing the new proxy hostname.

Replace $PROXY with the actual value returned from your query above. 
http -b -f POST :8112/api/v2/app/setPreferences 'Cookie:$COOKIE' \ 'json={"proxy_ip":"$PROXY"}'

That’s it. Your qBittorrent should now use the updated proxyserver.

You can put all this together in a shell script and add an * 2 * * * (every two hours) cronjob to keep the VPN proxy updated.

update-qbt-vpn.sh
#!/bin/bash
set -e

# Retrieve current recommended proxy from NordVPN website
PROXY=$(http https://nordvpn.com/wp-admin/admin-ajax.php\?action\=servers_recommendations\&filters\=\{"country_id":81,"servers_groups":\[15\],"servers_technologies":\[7\]\} | jq -r '.[0] | .hostname')
echo "The recommended proxy is: $PROXY"

# Retrieve login cookie for qBT WebUI
COOKIE=$(http :8112/api/v2/auth/login Referer:http://localhost:8112 -a 'username:password' -h --ignore-stdin | grep SID | awk '{print $2}')

# Get current Proxy
CURR_PROXY=$(http :8112/api/v2/app/preferences 'Cookie:$COOKIE' --ignore-stdin | jq '.' | jq -r '.proxy_ip')
echo "Configured proxy is: $CURR_PROXY"

if [[ $PROXY != $CURR_PROXY ]]
then
  # Write new Proxy
  http -b -f POST :8112/api/v2/app/setPreferences 'Cookie:$COOKIE' 'json={"proxy_ip":"'$PROXY'"}' --ignore-stdin
  echo "Updating configured proxy."
  http -b -f POST :8112/api/v2/torrents/pause 'Cookie:$COOKIE' 'hashes=all' --ignore-stdin
  echo "Pausing all torrent for 3 seconds"
  sleep 3s
  http -b -f POST :8112/api/v2/torrents/resume 'Cookie:$COOKIE' 'hashes=all' --ignore-stdin
  echo "Resumed all torrents"
else
  echo "Already using the recommended proxy."
fi

http -b POST :8112/api/v2/auth/logout Referer:http://localhost:8112 'Cookie:$COOKIE' --ignore-stdin

# Retrieve list of torrents
#http :8112/api/v2/torrents/info 'Cookie:$COOKIE'

# Get all preferences
#http :8112/api/v2/app/preferences 'Cookie:$COOKIE'