From 3f9ff57785cb230900ada3933faec2066368fcd8 Mon Sep 17 00:00:00 2001
From: Adam Wathan <adam.wathan@gmail.com>
Date: Fri, 11 Nov 2016 10:30:02 -0500
Subject: [PATCH] 2.9 - Handling Failed Charges

---
 app/Billing/FakePaymentGateway.php            |  3 +++
 app/Billing/PaymentFailedException.php        |  5 +++++
 .../Controllers/ConcertOrdersController.php   | 13 ++++++++----
 tests/features/PurchaseTicketsTest.php        | 21 ++++++++++++++-----
 tests/unit/Billing/FakePaymentGatewayTest.php | 14 +++++++++++++
 5 files changed, 47 insertions(+), 9 deletions(-)
 create mode 100644 app/Billing/PaymentFailedException.php

diff --git a/app/Billing/FakePaymentGateway.php b/app/Billing/FakePaymentGateway.php
index 5d62847..8f72e51 100644
--- a/app/Billing/FakePaymentGateway.php
+++ b/app/Billing/FakePaymentGateway.php
@@ -18,6 +18,9 @@ class FakePaymentGateway implements PaymentGateway
 
     public function charge($amount, $token)
     {
+        if ($token !== $this->getValidTestToken()) {
+            throw new PaymentFailedException;
+        }
         $this->charges[] = $amount;
     }
 
diff --git a/app/Billing/PaymentFailedException.php b/app/Billing/PaymentFailedException.php
new file mode 100644
index 0000000..efd1ae6
--- /dev/null
+++ b/app/Billing/PaymentFailedException.php
@@ -0,0 +1,5 @@
+<?php
+
+namespace App\Billing;
+
+class PaymentFailedException extends \RuntimeException {}
diff --git a/app/Http/Controllers/ConcertOrdersController.php b/app/Http/Controllers/ConcertOrdersController.php
index be60043..d7094b6 100644
--- a/app/Http/Controllers/ConcertOrdersController.php
+++ b/app/Http/Controllers/ConcertOrdersController.php
@@ -5,6 +5,7 @@ namespace App\Http\Controllers;
 use App\Concert;
 use Illuminate\Http\Request;
 use App\Billing\PaymentGateway;
+use App\Billing\PaymentFailedException;
 
 class ConcertOrdersController extends Controller
 {
@@ -23,10 +24,14 @@ class ConcertOrdersController extends Controller
             'payment_token' => ['required'],
         ]);
 
-        $concert = Concert::find($concertId);
-        $this->paymentGateway->charge(request('ticket_quantity') * $concert->ticket_price, request('payment_token'));
-        $order = $concert->orderTickets(request('email'), request('ticket_quantity'));
+        try {
+            $concert = Concert::find($concertId);
+            $this->paymentGateway->charge(request('ticket_quantity') * $concert->ticket_price, request('payment_token'));
+            $order = $concert->orderTickets(request('email'), request('ticket_quantity'));
 
-        return response()->json([], 201);
+            return response()->json([], 201);
+        } catch (PaymentFailedException $e) {
+            return response()->json([], 422);
+        }
     }
 }
diff --git a/tests/features/PurchaseTicketsTest.php b/tests/features/PurchaseTicketsTest.php
index 3edc82d..b1d6a84 100644
--- a/tests/features/PurchaseTicketsTest.php
+++ b/tests/features/PurchaseTicketsTest.php
@@ -32,26 +32,37 @@ class PurchaseTicketsTest extends TestCase
     /** @test */
     function customer_can_purchase_concert_tickets()
     {
-        // Arrange
         $concert = factory(Concert::class)->create(['ticket_price' => 3250]);
 
-        // Act
         $this->orderTickets($concert, [
             'email' => 'john@example.com',
             'ticket_quantity' => 3,
             'payment_token' => $this->paymentGateway->getValidTestToken(),
         ]);
 
-        // Assert
         $this->assertResponseStatus(201);
-
         $this->assertEquals(9750, $this->paymentGateway->totalCharges());
-
         $order = $concert->orders()->where('email', 'john@example.com')->first();
         $this->assertNotNull($order);
         $this->assertEquals(3, $order->tickets()->count());
     }
 
+    /** @test */
+    function an_order_is_not_created_if_payment_fails()
+    {
+        $concert = factory(Concert::class)->create(['ticket_price' => 3250]);
+
+        $this->orderTickets($concert, [
+            'email' => 'john@example.com',
+            'ticket_quantity' => 3,
+            'payment_token' => 'invalid-payment-token',
+        ]);
+
+        $this->assertResponseStatus(422);
+        $order = $concert->orders()->where('email', 'john@example.com')->first();
+        $this->assertNull($order);
+    }
+
     /** @test */
     function email_is_required_to_purchase_tickets()
     {
diff --git a/tests/unit/Billing/FakePaymentGatewayTest.php b/tests/unit/Billing/FakePaymentGatewayTest.php
index c1b0886..0e5e439 100644
--- a/tests/unit/Billing/FakePaymentGatewayTest.php
+++ b/tests/unit/Billing/FakePaymentGatewayTest.php
@@ -1,6 +1,7 @@
 <?php
 
 use App\Billing\FakePaymentGateway;
+use App\Billing\PaymentFailedException;
 use Illuminate\Foundation\Testing\WithoutMiddleware;
 use Illuminate\Foundation\Testing\DatabaseMigrations;
 use Illuminate\Foundation\Testing\DatabaseTransactions;
@@ -16,4 +17,17 @@ class FakePaymentGatewayTest extends TestCase
 
         $this->assertEquals(2500, $paymentGateway->totalCharges());
     }
+
+    /** @test */
+    function charges_with_an_invalid_payment_token_fail()
+    {
+        try {
+            $paymentGateway = new FakePaymentGateway;
+            $paymentGateway->charge(2500, 'invalid-payment-token');
+        } catch (PaymentFailedException $e) {
+            return;
+        }
+
+        $this->fail();
+    }
 }