Card: Remove try/catch from Approve Order Flow (#302)

* Rename ConfirmPaymentSourceResponse to ConfirmPaymentSourceResult.

* Remove throws from CardClient.approveOrder flow.

* Make if statement truthy.

* Clean up detekt errors.

* Remove coroutines exception handler from CardClient.approveOrder flow.

CardPayments/src/main/java/com/paypal/android/cardpayments/CardClient.kt

@@ -6,6 +6,7 @@ import android.net.Uri
 import android.util.Log
 import androidx.activity.ComponentActivity
 import com.paypal.android.cardpayments.api.CheckoutOrdersAPI
+import com.paypal.android.cardpayments.api.ConfirmPaymentSourceResult
 import com.paypal.android.corepayments.CoreConfig
 import com.paypal.android.corepayments.CoreCoroutineExceptionHandler
 import com.paypal.android.corepayments.PayPalSDKError
@@ -39,12 +40,6 @@ class CardClient internal constructor(
 
     private var approveOrderId: String? = null
 
-    // TODO: remove once try-catch is removed
-    private val approveOrderExceptionHandler = CoreCoroutineExceptionHandler { error ->
-        analytics.notifyApproveOrderUnknownError(null)
-        approveOrderListener?.onApproveOrderFailure(error)
-    }
-
     // TODO: remove once try-catch is removed
     private val vaultExceptionHandler = CoreCoroutineExceptionHandler { error ->
         analytics.notifyVaultUnknownError(null)
@@ -76,26 +71,28 @@ class CardClient internal constructor(
         approveOrderId = cardRequest.orderId
         analytics.notifyApproveOrderStarted(cardRequest.orderId)
 
-        CoroutineScope(dispatcher).launch(approveOrderExceptionHandler) {
-            // TODO: migrate away from throwing exceptions to result objects
-            try {
-                val response = checkoutOrdersAPI.confirmPaymentSource(cardRequest)
-                if (response.payerActionHref == null) {
-                    analytics.notifyApproveOrderSucceeded(response.orderId)
-                    val result =
-                        response.run { CardResult(orderId = orderId, status = status?.name) }
-                    approveOrderListener?.onApproveOrderSuccess(result)
-                } else {
-                    analytics.notifyApproveOrderAuthChallengeReceived(cardRequest.orderId)
-                    approveOrderListener?.onApproveOrderThreeDSecureWillLaunch()
+        CoroutineScope(dispatcher).launch {
+            when (val response = checkoutOrdersAPI.confirmPaymentSource(cardRequest)) {
+                is ConfirmPaymentSourceResult.Success -> {
+                    if (response.payerActionHref == null) {
+                        analytics.notifyApproveOrderSucceeded(response.orderId)
+                        val result =
+                            response.run { CardResult(orderId = orderId, status = status?.name) }
+                        approveOrderListener?.onApproveOrderSuccess(result)
+                    } else {
+                        analytics.notifyApproveOrderAuthChallengeReceived(cardRequest.orderId)
+                        approveOrderListener?.onApproveOrderThreeDSecureWillLaunch()
+
+                        val url = Uri.parse(response.payerActionHref)
+                        val authChallenge = CardAuthChallenge.ApproveOrder(url, cardRequest)
+                        approveOrderListener?.onApproveOrderAuthorizationRequired(authChallenge)
+                    }
+                }
 
-                    val url = Uri.parse(response.payerActionHref)
-                    val authChallenge = CardAuthChallenge.ApproveOrder(url, cardRequest)
-                    approveOrderListener?.onApproveOrderAuthorizationRequired(authChallenge)
+                is ConfirmPaymentSourceResult.Failure -> {
+                    analytics.notifyApproveOrderFailed(cardRequest.orderId)
+                    approveOrderListener?.onApproveOrderFailure(response.error)
                 }
-            } catch (error: PayPalSDKError) {
-                analytics.notifyApproveOrderFailed(cardRequest.orderId)
-                throw error
             }
         }
     }

CardPayments/src/main/java/com/paypal/android/cardpayments/CardResponseParser.kt

@@ -1,6 +1,6 @@
 package com.paypal.android.cardpayments
 
-import com.paypal.android.cardpayments.api.ConfirmPaymentSourceResponse
+import com.paypal.android.cardpayments.api.ConfirmPaymentSourceResult
 import com.paypal.android.cardpayments.model.PaymentSource
 import com.paypal.android.cardpayments.model.PurchaseUnit
 import com.paypal.android.corepayments.APIClientError
@@ -13,8 +13,7 @@ import org.json.JSONException
 
 internal class CardResponseParser {
 
-    @Throws(PayPalSDKError::class)
-    fun parseConfirmPaymentSourceResponse(httpResponse: HttpResponse): ConfirmPaymentSourceResponse =
+    fun parseConfirmPaymentSourceResponse(httpResponse: HttpResponse): ConfirmPaymentSourceResult =
         try {
             val bodyResponse = httpResponse.body!!
 
@@ -24,7 +23,7 @@ internal class CardResponseParser {
 
             // this section is for 3DS
             val payerActionHref = json.getLinkHref("payer-action")
-            ConfirmPaymentSourceResponse(
+            ConfirmPaymentSourceResult.Success(
                 id,
                 OrderStatus.valueOf(status),
                 payerActionHref,
@@ -33,7 +32,8 @@ internal class CardResponseParser {
             )
         } catch (ignored: JSONException) {
             val correlationId = httpResponse.headers["Paypal-Debug-Id"]
-            throw APIClientError.dataParsingError(correlationId)
+            val error = APIClientError.dataParsingError(correlationId)
+            ConfirmPaymentSourceResult.Failure(error)
         }
 
     fun parseError(httpResponse: HttpResponse): PayPalSDKError? {

CardPayments/src/main/java/com/paypal/android/cardpayments/api/CheckoutOrdersAPI.kt

@@ -13,15 +13,15 @@ internal class CheckoutOrdersAPI(
 ) {
     constructor(coreConfig: CoreConfig) : this(RestClient(coreConfig))
 
-    suspend fun confirmPaymentSource(cardRequest: CardRequest): ConfirmPaymentSourceResponse {
+    suspend fun confirmPaymentSource(cardRequest: CardRequest): ConfirmPaymentSourceResult {
         val apiRequest = requestFactory.createConfirmPaymentSourceRequest(cardRequest)
         val httpResponse = restClient.send(apiRequest)
 
         val error = responseParser.parseError(httpResponse)
-        if (error != null) {
-            throw error
+        return if (error == null) {
+            responseParser.parseConfirmPaymentSourceResponse(httpResponse)
         } else {
-            return responseParser.parseConfirmPaymentSourceResponse(httpResponse)
+            ConfirmPaymentSourceResult.Failure(error)
         }
     }
 }

CardPayments/src/main/java/com/paypal/android/cardpayments/api/ConfirmPaymentSourceResult.kt

@@ -0,0 +1,19 @@
+package com.paypal.android.cardpayments.api
+
+import com.paypal.android.cardpayments.model.PaymentSource
+import com.paypal.android.cardpayments.model.PurchaseUnit
+import com.paypal.android.corepayments.OrderStatus
+import com.paypal.android.corepayments.PayPalSDKError
+
+internal sealed class ConfirmPaymentSourceResult {
+
+    data class Success(
+        val orderId: String,
+        val status: OrderStatus? = null,
+        val payerActionHref: String? = null,
+        val paymentSource: PaymentSource? = null,
+        val purchaseUnits: List<PurchaseUnit>? = null
+    ) : ConfirmPaymentSourceResult()
+
+    data class Failure(val error: PayPalSDKError) : ConfirmPaymentSourceResult()
+}

CardPayments/src/test/java/com/paypal/android/cardpayments/CardClientUnitTest.kt

@@ -7,7 +7,7 @@ import androidx.fragment.app.FragmentActivity
 import androidx.lifecycle.Lifecycle
 import androidx.test.core.app.ApplicationProvider
 import com.paypal.android.cardpayments.api.CheckoutOrdersAPI
-import com.paypal.android.cardpayments.api.ConfirmPaymentSourceResponse
+import com.paypal.android.cardpayments.api.ConfirmPaymentSourceResult
 import com.paypal.android.corepayments.OrderStatus
 import com.paypal.android.corepayments.PayPalSDKError
 import io.mockk.Called
@@ -58,8 +58,8 @@ class CardClientUnitTest {
     private val paymentMethodTokensAPI = mockk<DataVaultPaymentMethodTokensAPI>(relaxed = true)
 
     private val cardAnalytics = mockk<CardAnalytics>(relaxed = true)
-    private val confirmPaymentSourceResponse =
-        ConfirmPaymentSourceResponse(orderId, OrderStatus.APPROVED)
+    private val confirmPaymentSourceResult =
+        ConfirmPaymentSourceResult.Success(orderId, OrderStatus.APPROVED)
 
     private val activity = mockk<FragmentActivity>(relaxed = true)
 
@@ -90,7 +90,7 @@ class CardClientUnitTest {
     fun `approve order notifies listener of confirm payment source success`() = runTest {
         val sut = createCardClient(testScheduler)
 
-        coEvery { checkoutOrdersAPI.confirmPaymentSource(cardRequest) } returns confirmPaymentSourceResponse
+        coEvery { checkoutOrdersAPI.confirmPaymentSource(cardRequest) } returns confirmPaymentSourceResult
 
         sut.approveOrder(cardRequest)
         advanceUntilIdle()
@@ -109,7 +109,9 @@ class CardClientUnitTest {
         val sut = createCardClient(testScheduler)
 
         val error = PayPalSDKError(0, "mock_error_message")
-        coEvery { checkoutOrdersAPI.confirmPaymentSource(cardRequest) } throws error
+        coEvery {
+            checkoutOrdersAPI.confirmPaymentSource(cardRequest)
+        } returns ConfirmPaymentSourceResult.Failure(error)
 
         sut.approveOrder(cardRequest)
         advanceUntilIdle()
@@ -124,7 +126,7 @@ class CardClientUnitTest {
     @Test
     fun `approveOrder() notifies listener when authorization is required`() = runTest {
         val threeDSecureAuthChallengeResponse =
-            ConfirmPaymentSourceResponse(orderId, OrderStatus.APPROVED, "/payer/action/href")
+            ConfirmPaymentSourceResult.Success(orderId, OrderStatus.APPROVED, "/payer/action/href")
 
         coEvery { checkoutOrdersAPI.confirmPaymentSource(cardRequest) } returns threeDSecureAuthChallengeResponse
 

CardPayments/src/test/java/com/paypal/android/cardpayments/CheckoutOrdersAPIUnitTest.kt

@@ -1,11 +1,11 @@
 package com.paypal.android.cardpayments
 
 import com.paypal.android.cardpayments.api.CheckoutOrdersAPI
+import com.paypal.android.cardpayments.api.ConfirmPaymentSourceResult
 import com.paypal.android.corepayments.APIRequest
 import com.paypal.android.corepayments.HttpMethod
 import com.paypal.android.corepayments.HttpResponse
 import com.paypal.android.corepayments.OrderStatus
-import com.paypal.android.corepayments.PayPalSDKError
 import com.paypal.android.corepayments.PaymentsJSON
 import com.paypal.android.corepayments.RestClient
 import io.mockk.coEvery
@@ -103,7 +103,7 @@ class CheckoutOrdersAPIUnitTest {
         val httpResponse = HttpResponse(200, headers, successBody)
         coEvery { restClient.send(apiRequest) } returns httpResponse
 
-        val result = sut.confirmPaymentSource(cardRequest)
+        val result = sut.confirmPaymentSource(cardRequest) as ConfirmPaymentSourceResult.Success
 
         assertEquals("test-order-id", result.orderId)
         assertEquals(OrderStatus.APPROVED, result.status)
@@ -114,17 +114,11 @@ class CheckoutOrdersAPIUnitTest {
         val httpResponse = HttpResponse(404, headers, errorBody)
         coEvery { restClient.send(apiRequest) } returns httpResponse
 
-        lateinit var capturedError: PayPalSDKError
-        try {
-            sut.confirmPaymentSource(cardRequest)
-        } catch (e: PayPalSDKError) {
-            capturedError = e
-        }
-
+        val result = sut.confirmPaymentSource(cardRequest) as ConfirmPaymentSourceResult.Failure
         assertEquals(
             "The specified resource does not exist. -> [Issue: INVALID_RESOURCE_ID.\n" +
                     "Error description: Specified resource ID does not exist.]",
-            capturedError.errorDescription
+            result.error.errorDescription
         )
     }
 
@@ -135,16 +129,10 @@ class CheckoutOrdersAPIUnitTest {
             val httpResponse = HttpResponse(-1, headers, errorBody)
             coEvery { restClient.send(apiRequest) } returns httpResponse
 
-            lateinit var capturedError: PayPalSDKError
-            try {
-                sut.confirmPaymentSource(cardRequest)
-            } catch (e: PayPalSDKError) {
-                capturedError = e
-            }
-
+            val result = sut.confirmPaymentSource(cardRequest) as ConfirmPaymentSourceResult.Failure
             assertEquals(
                 "An unknown error occurred. Contact developer.paypal.com/support.",
-                capturedError.errorDescription
+                result.error.errorDescription
             )
         }
 
@@ -155,16 +143,10 @@ class CheckoutOrdersAPIUnitTest {
             val httpResponse = HttpResponse(-10, headers, emptyErrorBody)
             coEvery { restClient.send(apiRequest) } returns httpResponse
 
-            lateinit var capturedError: PayPalSDKError
-            try {
-                sut.confirmPaymentSource(cardRequest)
-            } catch (e: PayPalSDKError) {
-                capturedError = e
-            }
-
+            val result = sut.confirmPaymentSource(cardRequest) as ConfirmPaymentSourceResult.Failure
             assertEquals(
                 "An error occurred due to missing HTTP response data. Contact developer.paypal.com/support.",
-                capturedError.errorDescription
+                result.error.errorDescription
             )
         }
 
@@ -177,16 +159,10 @@ class CheckoutOrdersAPIUnitTest {
             coEvery { restClient.send(apiRequest) } returns httpResponse
             every { paymentsJSON.getString(any()) } throws parsingException
 
-            lateinit var capturedError: PayPalSDKError
-            try {
-                sut.confirmPaymentSource(cardRequest)
-            } catch (e: PayPalSDKError) {
-                capturedError = e
-            }
-
+            val result = sut.confirmPaymentSource(cardRequest) as ConfirmPaymentSourceResult.Failure
             assertEquals(
                 "An error occurred parsing HTTP response data. Contact developer.paypal.com/support.",
-                capturedError.errorDescription
+                result.error.errorDescription
             )
         }
 
@@ -196,16 +172,10 @@ class CheckoutOrdersAPIUnitTest {
         val httpResponse = HttpResponse(-2, headers, errorBody)
         coEvery { restClient.send(apiRequest) } returns httpResponse
 
-        lateinit var capturedError: PayPalSDKError
-        try {
-            sut.confirmPaymentSource(cardRequest)
-        } catch (e: PayPalSDKError) {
-            capturedError = e
-        }
-
+        val result = sut.confirmPaymentSource(cardRequest) as ConfirmPaymentSourceResult.Failure
         assertEquals(
             "An error occurred due to an invalid HTTP response. Contact developer.paypal.com/support.",
-            capturedError.errorDescription
+            result.error.errorDescription
         )
     }
 
@@ -215,48 +185,29 @@ class CheckoutOrdersAPIUnitTest {
         val httpResponse = HttpResponse(-3, headers, errorBody)
         coEvery { restClient.send(apiRequest) } returns httpResponse
 
-        lateinit var capturedError: PayPalSDKError
-        try {
-            sut.confirmPaymentSource(cardRequest)
-        } catch (e: PayPalSDKError) {
-            capturedError = e
-        }
-
+        val result = sut.confirmPaymentSource(cardRequest) as ConfirmPaymentSourceResult.Failure
         assertEquals(
             "A server error occurred. Contact developer.paypal.com/support.",
-            capturedError.errorDescription
+            result.error.errorDescription
         )
     }
 
     @Test
     fun `when confirmPaymentSource fails to parse response, correlation ID is set in Error`() =
         runTest {
-            coEvery { restClient.send(apiRequest) } returns HttpResponse(
-                200,
-                headers,
-                unexpectedBody
-            )
+            coEvery {
+                restClient.send(apiRequest)
+            } returns HttpResponse(200, headers, unexpectedBody)
 
-            lateinit var capturedError: PayPalSDKError
-            try {
-                sut.confirmPaymentSource(cardRequest)
-            } catch (e: PayPalSDKError) {
-                capturedError = e
-            }
-            assertEquals(correlationId, capturedError.correlationId)
+            val result = sut.confirmPaymentSource(cardRequest) as ConfirmPaymentSourceResult.Failure
+            assertEquals(correlationId, result.error.correlationId)
         }
 
     @Test
     fun `when confirmPaymentSource is errors, correlation ID is set in Error`() = runTest {
         coEvery { restClient.send(apiRequest) } returns HttpResponse(400, headers, errorBody)
 
-        lateinit var capturedError: PayPalSDKError
-        try {
-            sut.confirmPaymentSource(cardRequest)
-        } catch (e: PayPalSDKError) {
-            capturedError = e
-        }
-
-        assertEquals(correlationId, capturedError.correlationId)
+        val result = sut.confirmPaymentSource(cardRequest) as ConfirmPaymentSourceResult.Failure
+        assertEquals(correlationId, result.error.correlationId)
     }
 }