PayPal: Remove Checkout Listener Pattern (#307)

* Migrate PaypalWebCheckoutClient.start away from listener pattern.

* Update unit tests.

* Remove PayPalWebStatus events for Checkout.

* Clean up view model style.

* Update CHANGELOG.

* Add missing CardClient CHANGELOG bullets.

CHANGELOG.md

@@ -5,6 +5,8 @@
   * Fix issue that causes analytics version number to always be `null`
 * Breaking Changes
   * CardPayments
+    * Remove `CardClient.approveOrderListener` property
+    * Remove `CardClient.cardVaultListener` property
     * Remove `ApproveOrderListener` type
     * Add `CardApproveOrderCallback` interface
     * Convert `CardApproveOrderResult` to a sealed class
@@ -21,6 +23,10 @@
     * Add `CardFinishVaultResult` type
     * Add `CardVaultCallback` interface
     * Convert `CardVaultResult` to a sealed class
+  * PayPalWebPayments
+    * Remove `PayPalWebCheckoutClient.listener` property
+    * Add `PayPalWebCheckoutClient.finishStart(Intent, String)` method
+    * Add `PayPalWebCheckoutFinishStartResult` type
 
 ## 2.0.0-beta1 (2024-11-20)
 * Breaking Changes

Demo/src/main/java/com/paypal/android/ui/paypalweb/PayPalWebUiState.kt

@@ -2,14 +2,14 @@ package com.paypal.android.ui.paypalweb
 
 import com.paypal.android.api.model.Order
 import com.paypal.android.api.model.OrderIntent
+import com.paypal.android.paypalwebpayments.PayPalWebCheckoutFinishStartResult
 import com.paypal.android.paypalwebpayments.PayPalWebCheckoutFundingSource
-import com.paypal.android.paypalwebpayments.PayPalWebCheckoutResult
 import com.paypal.android.uishared.state.ActionState
 
 data class PayPalWebUiState(
     val intentOption: OrderIntent = OrderIntent.AUTHORIZE,
     val createOrderState: ActionState<Order, Exception> = ActionState.Idle,
-    val payPalWebCheckoutState: ActionState<PayPalWebCheckoutResult, Exception> = ActionState.Idle,
+    val payPalWebCheckoutState: ActionState<PayPalWebCheckoutFinishStartResult.Success, Exception> = ActionState.Idle,
     val completeOrderState: ActionState<Order, Exception> = ActionState.Idle,
     val fundingSource: PayPalWebCheckoutFundingSource = PayPalWebCheckoutFundingSource.PAYPAL
 ) {

Demo/src/main/java/com/paypal/android/ui/paypalweb/PayPalWebViewModel.kt

@@ -1,29 +1,26 @@
 package com.paypal.android.ui.paypalweb
 
-import android.annotation.SuppressLint
 import android.content.Context
 import android.util.Log
 import androidx.activity.ComponentActivity
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import com.paypal.android.api.model.Order
 import com.paypal.android.api.model.OrderIntent
+import com.paypal.android.api.services.SDKSampleServerResult
 import com.paypal.android.corepayments.CoreConfig
-import com.paypal.android.corepayments.PayPalSDKError
 import com.paypal.android.fraudprotection.PayPalDataCollector
+import com.paypal.android.fraudprotection.PayPalDataCollectorRequest
 import com.paypal.android.models.OrderRequest
+import com.paypal.android.paypalwebpayments.PayPalPresentAuthChallengeResult
 import com.paypal.android.paypalwebpayments.PayPalWebCheckoutClient
+import com.paypal.android.paypalwebpayments.PayPalWebCheckoutFinishStartResult
 import com.paypal.android.paypalwebpayments.PayPalWebCheckoutFundingSource
-import com.paypal.android.paypalwebpayments.PayPalWebCheckoutListener
 import com.paypal.android.paypalwebpayments.PayPalWebCheckoutRequest
-import com.paypal.android.paypalwebpayments.PayPalWebCheckoutResult
 import com.paypal.android.uishared.state.ActionState
 import com.paypal.android.usecase.CompleteOrderUseCase
 import com.paypal.android.usecase.CreateOrderUseCase
 import com.paypal.android.usecase.GetClientIdUseCase
-import com.paypal.android.api.services.SDKSampleServerResult
-import com.paypal.android.fraudprotection.PayPalDataCollectorRequest
-import com.paypal.android.paypalwebpayments.PayPalPresentAuthChallengeResult
 import dagger.hilt.android.lifecycle.HiltViewModel
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.asStateFlow
@@ -36,7 +33,7 @@ class PayPalWebViewModel @Inject constructor(
     val getClientIdUseCase: GetClientIdUseCase,
     val createOrderUseCase: CreateOrderUseCase,
     val completeOrderUseCase: CompleteOrderUseCase
-) : ViewModel(), PayPalWebCheckoutListener {
+) : ViewModel() {
 
     companion object {
         private val TAG = PayPalWebViewModel::class.qualifiedName
@@ -118,51 +115,35 @@ class PayPalWebViewModel @Inject constructor(
 
                 paypalClient =
                     PayPalWebCheckoutClient(activity, coreConfig, "com.paypal.android.demo")
-                paypalClient?.listener = this@PayPalWebViewModel
-
-                paypalClient?.start(activity, PayPalWebCheckoutRequest(orderId, fundingSource))?.let { startResult ->
-                    when (startResult) {
-                        is PayPalPresentAuthChallengeResult.Success -> {
-                            authState = startResult.authState
-                        }
-                        is PayPalPresentAuthChallengeResult.Failure -> {
-                            payPalWebCheckoutState = ActionState.Failure(startResult.error)
-                        }
+
+                val checkoutRequest = PayPalWebCheckoutRequest(orderId, fundingSource)
+                when (val startResult = paypalClient?.start(activity, checkoutRequest)) {
+                    is PayPalPresentAuthChallengeResult.Success ->
+                        authState = startResult.authState
+
+                    is PayPalPresentAuthChallengeResult.Failure ->
+                        payPalWebCheckoutState = ActionState.Failure(startResult.error)
+
+                    null -> {
+                        // do nothing
                     }
                 }
             }
         }
     }
 
-    @SuppressLint("SetTextI18n")
-    override fun onPayPalWebSuccess(result: PayPalWebCheckoutResult) {
-        Log.i(TAG, "Order Approved: ${result.orderId} && ${result.payerId}")
-        payPalWebCheckoutState = ActionState.Success(result)
-    }
-
-    @SuppressLint("SetTextI18n")
-    override fun onPayPalWebFailure(error: PayPalSDKError) {
-        Log.i(TAG, "Checkout Error: ${error.errorDescription}")
-        payPalWebCheckoutState = ActionState.Failure(error)
-    }
-
-    @SuppressLint("SetTextI18n")
-    override fun onPayPalWebCanceled() {
-        Log.i(TAG, "User cancelled")
-        val error = Exception("USER CANCELED")
-        payPalWebCheckoutState = ActionState.Failure(error)
-    }
-
     fun completeOrder(context: Context) {
         val orderId = createdOrder?.id
         if (orderId == null) {
             completeOrderState = ActionState.Failure(Exception("Create an order to continue."))
         } else {
             viewModelScope.launch {
                 completeOrderState = ActionState.Loading
-                val dataCollectorRequest = PayPalDataCollectorRequest(hasUserLocationConsent = false)
+                val dataCollectorRequest =
+                    PayPalDataCollectorRequest(hasUserLocationConsent = false)
                 val cmid = payPalDataCollector.collectDeviceData(context, dataCollectorRequest)
-                completeOrderState = completeOrderUseCase(orderId, intentOption, cmid).mapToActionState()
+                completeOrderState =
+                    completeOrderUseCase(orderId, intentOption, cmid).mapToActionState()
             }
         }
     }
@@ -173,6 +154,25 @@ class PayPalWebViewModel @Inject constructor(
     }
 
     fun handleBrowserSwitchResult(activity: ComponentActivity) {
-        authState?.let { paypalClient?.completeAuthChallenge(activity.intent, it) }
+        val result = authState?.let { paypalClient?.finishStart(activity.intent, it) }
+        when (result) {
+            is PayPalWebCheckoutFinishStartResult.Success -> {
+                payPalWebCheckoutState = ActionState.Success(result)
+            }
+
+            is PayPalWebCheckoutFinishStartResult.Canceled -> {
+                val error = Exception("USER CANCELED")
+                payPalWebCheckoutState = ActionState.Failure(error)
+            }
+
+            is PayPalWebCheckoutFinishStartResult.Failure -> {
+                Log.i(TAG, "Checkout Error: ${result.error.errorDescription}")
+                payPalWebCheckoutState = ActionState.Failure(result.error)
+            }
+
+            null, PayPalWebCheckoutFinishStartResult.NoResult -> {
+                // do nothing
+            }
+        }
     }
 }

PayPalWebPayments/src/main/java/com/paypal/android/paypalwebpayments/PayPalWebCheckoutClient.kt

@@ -30,11 +30,6 @@ class PayPalWebCheckoutClient internal constructor(
         PayPalWebLauncher(urlScheme, configuration),
     )
 
-    /**
-     * Sets a listener to receive notifications when a PayPal Checkout event occurs.
-     */
-    var listener: PayPalWebCheckoutListener? = null
-
     /**
      * Sets a listener to receive notifications when a Paypal Vault event occurs.
      */
@@ -54,7 +49,6 @@ class PayPalWebCheckoutClient internal constructor(
         when (result) {
             is PayPalPresentAuthChallengeResult.Failure -> {
                 analytics.notifyCheckoutAuthChallengeFailed(request.orderId)
-                listener?.onPayPalWebFailure(result.error)
             }
 
             is PayPalPresentAuthChallengeResult.Success ->
@@ -86,44 +80,54 @@ class PayPalWebCheckoutClient internal constructor(
         return result
     }
 
-    fun completeAuthChallenge(intent: Intent, authState: String): PayPalWebStatus {
-        val status = payPalWebLauncher.completeAuthRequest(intent, authState)
-        when (status) {
-            is PayPalWebStatus.CheckoutSuccess -> {
-                analytics.notifyCheckoutAuthChallengeSucceeded(status.result.orderId)
-                listener?.onPayPalWebSuccess(status.result)
+    fun finishStart(intent: Intent, authState: String): PayPalWebCheckoutFinishStartResult {
+        val result = payPalWebLauncher.completeCheckoutAuthRequest(intent, authState)
+        when (result) {
+            is PayPalWebCheckoutFinishStartResult.Success -> {
+                analytics.notifyCheckoutAuthChallengeSucceeded(result.orderId)
+            }
+
+            is PayPalWebCheckoutFinishStartResult.Canceled -> {
+                analytics.notifyCheckoutAuthChallengeCanceled(result.orderId)
             }
 
-            is PayPalWebStatus.CheckoutError -> {
-                analytics.notifyCheckoutAuthChallengeFailed(status.orderId)
-                listener?.onPayPalWebFailure(status.error)
+            is PayPalWebCheckoutFinishStartResult.Failure -> {
+                analytics.notifyCheckoutAuthChallengeFailed(result.orderId)
             }
 
-            is PayPalWebStatus.CheckoutCanceled -> {
-                analytics.notifyCheckoutAuthChallengeCanceled(status.orderId)
-                listener?.onPayPalWebCanceled()
+            PayPalWebCheckoutFinishStartResult.NoResult -> {
+                // no analytics tracking required at the moment
             }
+        }
+        return result
+    }
 
+    fun completeAuthChallenge(intent: Intent, authState: String): PayPalWebStatus {
+        val status = payPalWebLauncher.completeAuthRequest(intent, authState)
+        when (status) {
             is PayPalWebStatus.VaultSuccess -> {
                 // TODO: see if we can get setup token id from somewhere
                 analytics.notifyVaultAuthChallengeSucceeded(null)
                 vaultListener?.onPayPalWebVaultSuccess(status.result)
             }
+
             is PayPalWebStatus.VaultError -> {
                 // TODO: see if we can get setup token id from somewhere
                 analytics.notifyVaultAuthChallengeFailed(null)
                 vaultListener?.onPayPalWebVaultFailure(status.error)
             }
+
             PayPalWebStatus.VaultCanceled -> {
                 // TODO: see if we can get setup token id from somewhere
                 analytics.notifyVaultAuthChallengeCanceled(null)
                 vaultListener?.onPayPalWebVaultCanceled()
             }
+
             is PayPalWebStatus.UnknownError -> {
                 Log.d("PayPalSDK", "An unknown error occurred: ${status.error.message}")
             }
 
-            PayPalWebStatus.NoResult -> {
+            else -> {
                 // ignore
             }
         }
@@ -135,6 +139,5 @@ class PayPalWebCheckoutClient internal constructor(
      */
     fun removeObservers() {
         vaultListener = null
-        listener = null
     }
 }

PayPalWebPayments/src/main/java/com/paypal/android/paypalwebpayments/PayPalWebCheckoutFinishStartResult.kt

@@ -0,0 +1,10 @@
+package com.paypal.android.paypalwebpayments
+
+import com.paypal.android.corepayments.PayPalSDKError
+
+sealed class PayPalWebCheckoutFinishStartResult {
+    class Success(val orderId: String?, val payerId: String?) : PayPalWebCheckoutFinishStartResult()
+    class Failure(val error: PayPalSDKError, val orderId: String?) : PayPalWebCheckoutFinishStartResult()
+    class Canceled(val orderId: String?) : PayPalWebCheckoutFinishStartResult()
+    data object NoResult : PayPalWebCheckoutFinishStartResult()
+}

PayPalWebPayments/src/main/java/com/paypal/android/paypalwebpayments/PayPalWebLauncher.kt

@@ -10,6 +10,7 @@ import com.braintreepayments.api.BrowserSwitchStartResult
 import com.paypal.android.corepayments.BrowserSwitchRequestCodes
 import com.paypal.android.corepayments.CoreConfig
 import com.paypal.android.corepayments.Environment
+import com.paypal.android.corepayments.PayPalSDKError
 import com.paypal.android.paypalwebpayments.errors.PayPalWebCheckoutError
 import org.json.JSONObject
 
@@ -106,6 +107,25 @@ internal class PayPalWebLauncher(
             .build()
     }
 
+    fun completeCheckoutAuthRequest(
+        intent: Intent,
+        authState: String
+    ): PayPalWebCheckoutFinishStartResult {
+        return when (val finalResult = browserSwitchClient.completeRequest(intent, authState)) {
+            is BrowserSwitchFinalResult.Success -> parseWebCheckoutSuccessResult(finalResult)
+            is BrowserSwitchFinalResult.Failure -> {
+                // TODO: remove error codes and error description from project; the built in
+                // Throwable type already has a message property and error codes are only required
+                // for iOS Error protocol conformance
+                val message = "Browser switch failed"
+                val browserSwitchError = PayPalSDKError(0, message, reason = finalResult.error)
+                PayPalWebCheckoutFinishStartResult.Failure(browserSwitchError, null)
+            }
+
+            BrowserSwitchFinalResult.NoResult -> PayPalWebCheckoutFinishStartResult.NoResult
+        }
+    }
+
     fun completeAuthRequest(intent: Intent, authState: String): PayPalWebStatus {
         return when (val finalResult = browserSwitchClient.completeRequest(intent, authState)) {
             is BrowserSwitchFinalResult.Success -> parseBrowserSwitchSuccessResult(finalResult)
@@ -116,25 +136,31 @@ internal class PayPalWebLauncher(
 
     private fun parseBrowserSwitchSuccessResult(result: BrowserSwitchFinalResult.Success) =
         when (result.requestCode) {
-            BrowserSwitchRequestCodes.PAYPAL_CHECKOUT -> parseWebCheckoutSuccessResult(result)
             BrowserSwitchRequestCodes.PAYPAL_VAULT -> parseVaultSuccessResult(result)
             else -> PayPalWebStatus.NoResult
         }
 
-    private fun parseWebCheckoutSuccessResult(finalResult: BrowserSwitchFinalResult.Success): PayPalWebStatus {
+    private fun parseWebCheckoutSuccessResult(
+        finalResult: BrowserSwitchFinalResult.Success
+    ): PayPalWebCheckoutFinishStartResult {
         val deepLinkUrl = finalResult.returnUrl
         val metadata = finalResult.requestMetadata
-
-        return if (metadata == null) {
-            PayPalWebStatus.CheckoutError(PayPalWebCheckoutError.unknownError, null)
-        } else {
-            val payerId = deepLinkUrl.getQueryParameter("PayerID")
-            val orderId = metadata.optString(METADATA_KEY_ORDER_ID)
-            if (orderId.isNullOrBlank() || payerId.isNullOrBlank()) {
-                PayPalWebStatus.CheckoutError(PayPalWebCheckoutError.malformedResultError, orderId)
+        return if (finalResult.requestCode == BrowserSwitchRequestCodes.PAYPAL_CHECKOUT) {
+            if (metadata == null) {
+                val unknownError = PayPalWebCheckoutError.unknownError
+                PayPalWebCheckoutFinishStartResult.Failure(unknownError, null)
             } else {
-                PayPalWebStatus.CheckoutSuccess(PayPalWebCheckoutResult(orderId, payerId))
+                val payerId = deepLinkUrl.getQueryParameter("PayerID")
+                val orderId = metadata.optString(METADATA_KEY_ORDER_ID)
+                if (orderId.isNullOrBlank() || payerId.isNullOrBlank()) {
+                    val malformedResultError = PayPalWebCheckoutError.malformedResultError
+                    PayPalWebCheckoutFinishStartResult.Failure(malformedResultError, orderId)
+                } else {
+                    PayPalWebCheckoutFinishStartResult.Success(orderId, payerId)
+                }
             }
+        } else {
+            PayPalWebCheckoutFinishStartResult.NoResult
         }
     }
 

PayPalWebPayments/src/main/java/com/paypal/android/paypalwebpayments/PayPalWebStatus.kt

@@ -4,10 +4,6 @@ import com.paypal.android.corepayments.PayPalSDKError
 
 sealed class PayPalWebStatus {
 
-    class CheckoutError(val error: PayPalSDKError, val orderId: String?) : PayPalWebStatus()
-    class CheckoutSuccess(val result: PayPalWebCheckoutResult) : PayPalWebStatus()
-    class CheckoutCanceled(val orderId: String?) : PayPalWebStatus()
-
     class VaultError(val error: PayPalSDKError) : PayPalWebStatus()
     class VaultSuccess(val result: PayPalWebVaultResult) : PayPalWebStatus()
     data object VaultCanceled : PayPalWebStatus()