This oracle takes an IP address and returns the address's country code, along with a signature for Mina zkApps. (The country lookup uses ip-api.com, but there are many other Geo IP lookups available with different pricing schemes.)

Run the key generator script below to create a private/public key pair.

npm run keygen

Create a .env file with a PRIVATE_KEY= entry for the private key.

Start the server locally with

npm run dev

Once the server has started, you can check out the API using http://localhost:3000/ip/[IP-address], replacing [IP-address] with some IP address.

npm run test

The API is just a NodeJS + ExpressJS server. For convenience, you can deploy it on Digital Ocean using this link:

During deployment, make sure you properly set the environment variable PRIVATE_KEY in the hosting environment (i.e. Digital Ocean). For security, this production private key should be different from what's used locally and not be shared among developers.

An example call could be found at https://mina-geoip-oracle-9mbb8.ondigitalocean.app/ip/24.48.0.1.