Silent Revalidation

PrepareInfo attributes

Attribute	Type	Required	Description
externalUserId	String	✅	User identifier in your system. Automatically hashed with SHA-256 before transmission, never sent in plain text.

Starting a Silent Revalidation

Step 1 — Implement initializeSDK

Create a new UnicoSDK class/object, with a static initializeSDK method that returns the UnicoSDK instance, receiving the context and a UnicoSDKConfig with your sdkKey, bundleId, and environment. Keep the returned instance — it is needed later to call startSilentValidation from Java.

Call it on app launch

UnicoSDK.initializeSDK must be called as early as possible on app launch (e.g., Application.onCreate). Calling it later reduces background processing time and increases the chance of inconclusive authentication responses.

Kotlin

UnicoSDK.initializeSDK(
    context,
    UnicoSDKConfig(
        sdkKey = "your_sdk_key",
        bundleId = "your_bundle_id",
        environment = Environment.UAT
    )
)

Java

UnicoSDK sdk = UnicoSDK.initializeSDK(
    context,
    new UnicoSDKConfig("your_sdk_key", "your_bundle_id", Environment.UAT)
);

Step 2 — Implement startSilentValidation

After initializeSDK, associate the collection already in progress with the identified user by calling startSilentValidation with a PrepareInfo containing the externalUserId.

Kotlin

val prepareInfo = PrepareInfo(
    externalUserId = "external_user_id"
)

UnicoSDK.startSilentValidation(prepareInfo)
    .onSuccess { result -> /* ... */ }
    .onFailure { error -> /* ... */ }

Java

Java requires a Kotlin bridge

startSilentValidation is a Kotlin suspend function — Java can't call it directly. Use the bridge below to make the connection.

interface SilentAuthCallback {
    fun onSuccess(success: Boolean)
    fun onFailure(message: String?)
}

object SilentAuthBridge {

    @JvmStatic
    fun startSilentValidation(
        owner: LifecycleOwner,
        sdk: UnicoSDK,
        externalUserId: String,
        callback: SilentAuthCallback
    ) {
        owner.lifecycleScope.launch {
            val result = sdk.startSilentValidation(PrepareInfo(externalUserId, null))
            result.onSuccess { callback.onSuccess(it.success) }
                .onFailure { callback.onFailure(it.message) }
        }
    }
}

SilentAuthBridge.startSilentValidation(this, sdk, externalUserId, new SilentAuthCallback() {
    @Override
    public void onSuccess(boolean success) {
        /* ... */
    }

    @Override
    public void onFailure(String message) {
        /* ... */
    }
});

If the validation happens at the start of the flow, for example at login, wait for the onSuccess callback before moving on to Step 3.

Step 3 — Create the process and authenticate

With validation in progress, create the verification process to complete the authentication. See API Reference ▸ API ▸ Create Process.

Include the same externalUserId sent in the PrepareInfo from Step 2 in the request body — this is what allows the backend to correlate the process creation with the validation already in progress.

curl -X POST https://api.id.unico.app/processes/v1 \
  -H "Authorization: Bearer $TOKEN" \
  -H "APIKEY: $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "subject": {
      "duiType": 1,
      "code": "12345678909",
      "name": "Luke Skywalker",
      "gender": "M",
      "birthDate": "2000-05-20",
      "email": "[email protected]",
      "phone": "5519725570707"
    },
    "useCase": "Onboarding",
    "externalUserId": "external_user_id",
    "imageBase64": "/9j/4AAQSkZJR..."
  }'

The response includes the silentAuth.result field with the authentication result:

{
    "id": "80371b2a-3ac7-432e-866d-57fe37896ac6",
    "status": 3,
    "silentAuth": {
        "result": "yes"
    }
}

Field	Type	Description
silentAuth.result	string	yes or no — see possible values below.

silentAuth.result — possible values

Value	Meaning
yes	Authentication approved, user recognized with sufficient confidence, no additional capture needed.
no	Insufficient data to approve silently. Authenticating via biometrics (selfie) or another alternative method is recommended.