Page Comparison

...

Please note, if the merchant’s 3DS Provider is Cardinal, Flow 3 C is irrelevant and can be disregarded.

Flow A: 3Ds complete

If the response contains ECI and CAVV values, the 3DS step is complete and the merchant can proceed to call the SALE api with these values.

...

https://netvalve.atlassian.net/wiki/spaces/ND/pages/54395064/V2+Step+4%3A+ACS+challenge+and+receive+challenge+result

V2 Step 5: 3DS Result API (Flows B, C)

https://netvalve.atlassian.net/wiki/spaces/ND/pages/54395121/V2+Step+6%3A+Add+3DS+fields+in+Sale+API

...

The Auth API response will indicate 2 possible flows - Flow A and Flow B described above. The response structure and properties are exactly the same as the initialization response.

See:

V2 Step 2: Create Device Data Collection Iframe and POST event listener(Flow C)

V2 Step 3: 3DS Auth API3DS Auth API (Flow C)

Example logic for flows

Here is a minimal example of the logic that would be used to determine which flow to begin:

// START 3DS Flow
const response = await initialize(); 
if (response.responseCode !== '3DS_1000') return handleError(response);
else if (response.threeDSProviderResponse.eci && response.threeDSProviderResponse.cavv) // Flow A - 3DS complete
    sale(response.threeDSProviderResponse);
else if (response.threeDSProviderResponse.status === 'ACS_REQUIRED') // Flow B - challenge required
    redirectToChallengePage(response);
else if (response.threeDSProviderResponse.status === 'INITIALIZED') // Flow C - device data collection required
    deviceDataCollection(response);