block-by-country

Block by Client Country

This sample illustrates how you could block clients from accessing a particular resource by maintaining an Country blocklist.

For demonstration purposes, the blocklist could be accessed using the /admin/blocked-countries endpoints.

The route / uses the blockByCountry middleware to validate incoming requests against the blocklist.

Behind the covers, ip-api.com is used to lookup the country using the IP address of the client.

Caution: This sample does not work when running on your local machine because ip-api.com does not respond to calls with a client IP address of 127.0.0.1.

Deploy to FWF and Run the Spin App

Once you've cloned the repository and moved to the ./samples/block-by-country, install the dependencies, build and run the app:

spin build
spin aka deploy

The spin aka deploy command will print the application URL to stdout. Store the URL in a variable called APP_URL:

export APP_URL=<YOUR_APP_URL>

Accessing the protected route

Send a GET request to the / route, which will show the data if your IP is not blocked:

curl -iX GET $APP_URL

HTTP/1.1 200 OK
content-type: application/json
content-length: 86
date: Fri, 24 Jan 2025 13:02:50 GMT

{"message":"If you can read this, you've successfully passed the blocking mechanism."}

Block your own Country

To block your own country, send a POST request to /admin/blocked-countries

curl -iX POST $APP_URL/admin/blocked-countries

HTTP/1.1 200 OK
content-type: application/json
content-length: 58
date: Fri, 24 Jan 2025 13:01:21 GMT

{"message":"Your Country (Germany) is already on the blocklist"}

Try to access the protected route again

Again, send a GET request to /, this time you should see the request being blocked with a 401:

curl -iX GET $APP_URL

HTTP/1.1 401 Unauthorized
content-length: 25
content-type: text/plain;charset=UTF-8
date: Fri, 24 Jan 2025 12:59:50 GMT

Sorry, your Country (Germany) is blocked

Retrieve the Country blocklist

To get the list of blocked countries send a GET request to /admin/blocked-countries

curl -iX GET $APP_URL/admin/blocked-countries

HTTP/1.1 200 OK
content-type: application/json
content-length: 13
date: Fri, 24 Jan 2025 13:02:02 GMT

["Germany"]

Clear the country blocklist

To clear the country blocklist, send a DELETE request to /admin/blocked-countries

curl -iX DELETE $APP_URL/admin/blocked-countries

HTTP/1.1 204 No Content
date: Fri, 24 Jan 2025 13:02:26 GMT