(C#) HMRC Validate Fraud Prevention Headers

Demonstrates how to test (validate) HMRC fraud prevention headers.

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// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

Chilkat.Rest rest = new Chilkat.Rest();

bool success = rest.Connect("test-api.service.hmrc.gov.uk",443,true,true);
if (success == false) {
    Debug.WriteLine(rest.LastErrorText);
    return;
}

// Load the previously fetched access token.
Chilkat.JsonObject json = new Chilkat.JsonObject();
success = json.LoadFile("qa_data/tokens/hmrc.json");
string accessToken = json.StringOf("access_token");
Debug.WriteLine("Using access toke: " + accessToken);

Chilkat.StringBuilder sbAuthHeaderValue = new Chilkat.StringBuilder();
sbAuthHeaderValue.Append("Bearer ");
sbAuthHeaderValue.Append(accessToken);

rest.AddHeader("Accept","application/vnd.hmrc.1.0+json");
rest.AddHeader("Authorization",sbAuthHeaderValue.GetAsString());

// Add the fraud prevention headers.
// See https://developer.service.hmrc.gov.uk/api-documentation/docs/fraud-prevention
rest.AddHeader("gov-client-connection-method","DESKTOP_APP_DIRECT");

// This should be generated by an application and persistently stored on the device. The identifier should not expire.
rest.AddHeader("gov-client-device-id","beec798b-b366-47fa-b1f8-92cede14a1ce");

// See https://developer.service.hmrc.gov.uk/api-documentation/docs/fraud-prevention
rest.AddHeader("gov-client-user-ids","os=user123");

// Your local IP addresses (comma separated), such as addresses beginning with "192.168." or "172.16."
rest.AddHeader("gov-client-local-ips","172.16.16.23");
// You'll need to find a way to get your MAC address.  Chilkat does not yet provide this ability...
rest.AddHeader("gov-client-mac-addresses","7C%3AD3%3A0A%3A25%3ADA%3A1C");

rest.AddHeader("gov-client-timezone","UTC+00:00");

// You can probably just hard-code these so they're always the same with each request.
rest.AddHeader("gov-client-window-size","width=1256&height=800");
rest.AddHeader("gov-client-screens","width=1920&height=1080&scaling-factor=1&colour-depth=16");
rest.AddHeader("gov-client-user-agent","Windows/Server%202012 (Dell%20Inc./OptiPlex%20980)");
rest.AddHeader("gov-vendor-version","My%20Desktop%20Software=1.2.3.build4286");

string responseStr = rest.FullRequestNoBody("GET","/test/fraud-prevention-headers/validate");
if (rest.LastMethodSuccess == false) {
    Debug.WriteLine(rest.LastErrorText);
    return;
}

// If the status code is 200, then the fraud prevention headers were validated.
// The JSON response may include some warnings..
Debug.WriteLine("Response status code = " + Convert.ToString(rest.ResponseStatusCode));
Debug.WriteLine("Response JSON body: ");
Debug.WriteLine(responseStr);