Tech test

ClearBank.DeveloperTest.Tests/ClearBank.DeveloperTest.Tests.csproj

@@ -5,6 +5,18 @@
     <IsTestProject>true</IsTestProject>
   </PropertyGroup>
 
+  <ItemGroup>
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.0.0" />
+    <PackageReference Include="Moq" Version="4.20.72" />
+    <PackageReference Include="MSTest.TestAdapter" Version="3.11.0" />
+    <PackageReference Include="MSTest.TestFramework" Version="3.11.0" />
+    <PackageReference Include="xunit" Version="2.9.3" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="3.1.5">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
+  </ItemGroup>
+
   <ItemGroup>
     <ProjectReference Include="..\ClearBank.DeveloperTest\ClearBank.DeveloperTest.csproj" />
   </ItemGroup>

ClearBank.DeveloperTest.Tests/PaymentServiceTests.cs

@@ -0,0 +1,182 @@
+using ClearBank.DeveloperTest.Data;
+using ClearBank.DeveloperTest.Services;
+using ClearBank.DeveloperTest.Types;
+using Microsoft.Extensions.Logging;
+using Moq;
+using Xunit;
+
+namespace ClearBank.DeveloperTest.Tests
+{
+    public class PaymentServiceTests
+    {
+        private readonly Mock<IAccountDataStore> _accountDataStoreMock;
+
+        private readonly Mock<ILogger<PaymentService>> _loggerMock;
+
+        public PaymentServiceTests()
+        {
+            _accountDataStoreMock = new Mock<IAccountDataStore>();
+            _loggerMock = new Mock<ILogger<PaymentService>>();
+        }
+
+        //Define special condition accounts to be used in tests
+        private readonly Account _accountNoBacs = new Account
+        {
+            AccountNumber = "123456",
+            Balance = 500,
+            Status = AccountStatus.Live,
+            AllowedPaymentSchemes = AllowedPaymentSchemes.FasterPayments | AllowedPaymentSchemes.Chaps
+        };
+
+        private readonly Account _noBalanceFasterPaymentAccount = new Account
+        {
+            AccountNumber = "111222",
+            Balance = 0,
+            Status = AccountStatus.Live,
+            AllowedPaymentSchemes = AllowedPaymentSchemes.FasterPayments
+        };
+
+        private readonly Account _disabledChapsAccount = new Account
+        {
+            AccountNumber = "111222",
+            Balance = 500,
+            Status = AccountStatus.Disabled,
+            AllowedPaymentSchemes = AllowedPaymentSchemes.Chaps
+        };
+
+        [Fact]
+        public void MakePayment_ShouldReturnFalse_WhenAccountIsNull()
+        {
+            // Arrange
+            var paymentService = new PaymentService(_accountDataStoreMock.Object, _loggerMock.Object);
+            var request = new MakePaymentRequest
+            {
+                DebtorAccountNumber = "12345678",
+                Amount = 100,
+                PaymentScheme = PaymentScheme.Bacs
+            };
+            _accountDataStoreMock.Setup(x => x.GetAccount(request.DebtorAccountNumber)).Returns((Account)null);
+            // Act
+            var result = paymentService.MakePayment(request);
+            // Assert
+            Assert.False(result.Success);
+        }
+
+        [Fact]
+        public void MakeBacsPayment_ShouldReturnFalse_WhenAccountBacsPaymentSchemeIsDisallowed()
+        {
+            // Arrange
+            var paymentService = new PaymentService(_accountDataStoreMock.Object, _loggerMock.Object);
+            var request = new MakePaymentRequest
+            {
+                DebtorAccountNumber = "12345678",
+                Amount = 100,
+                PaymentScheme = PaymentScheme.Bacs
+            };
+            _accountDataStoreMock.Setup(x => x.GetAccount(request.DebtorAccountNumber)).Returns(_accountNoBacs);
+            // Act
+            var result = paymentService.MakePayment(request);
+            // Assert
+            Assert.False(result.Success);
+        }
+
+        [Fact]
+        public void MakeFasterPaymentsPayment_ShouldReturnFalse_WhenAccountHasZeroBalance()
+        {
+            // Arrange
+            var paymentService = new PaymentService(_accountDataStoreMock.Object, _loggerMock.Object);
+            var request = new MakePaymentRequest
+            {
+                DebtorAccountNumber = "12345678",
+                Amount = 100,
+                PaymentScheme = PaymentScheme.FasterPayments
+            };
+            _accountDataStoreMock.Setup(x => x.GetAccount(request.DebtorAccountNumber)).Returns(_noBalanceFasterPaymentAccount);
+            // Act
+            var result = paymentService.MakePayment(request);
+            // Assert
+            Assert.False(result.Success);
+        }
+
+        [Fact]
+        public void MakeChapsPayment_ShouldReturnFalse_WhenAccountAccountStatusIsDisabled()
+        {
+            // Arrange
+            var paymentService = new PaymentService(_accountDataStoreMock.Object, _loggerMock.Object);
+            var request = new MakePaymentRequest
+            {
+                DebtorAccountNumber = "12345678",
+                Amount = 100,
+                PaymentScheme = PaymentScheme.Chaps
+            };
+            _accountDataStoreMock.Setup(x => x.GetAccount(request.DebtorAccountNumber)).Returns(_disabledChapsAccount);
+            // Act
+            var result = paymentService.MakePayment(request);
+            // Assert
+            Assert.False(result.Success);
+        }
+
+        [Theory]
+        [InlineData(PaymentScheme.Bacs, AllowedPaymentSchemes.Bacs)]
+        [InlineData(PaymentScheme.FasterPayments, AllowedPaymentSchemes.FasterPayments)]
+        [InlineData(PaymentScheme.Chaps, AllowedPaymentSchemes.Chaps)]
+        [InlineData(PaymentScheme.Bacs, AllowedPaymentSchemes.Bacs | AllowedPaymentSchemes.Chaps | AllowedPaymentSchemes.FasterPayments)]
+        [InlineData(PaymentScheme.Chaps, AllowedPaymentSchemes.Chaps | AllowedPaymentSchemes.FasterPayments)]
+        [InlineData(PaymentScheme.FasterPayments, AllowedPaymentSchemes.Bacs | AllowedPaymentSchemes.FasterPayments)]
+        public void MakePayment_ShouldReturnTrue_WhenAccountIsActive_AndHasCorrectPaymentScheme(PaymentScheme paymentScheme, AllowedPaymentSchemes allowedPaymentSchemes)
+        {
+            // Arrange
+            var paymentService = new PaymentService(_accountDataStoreMock.Object, _loggerMock.Object);
+
+            var account = new Account
+            {
+                AccountNumber = "12345678",
+                Balance = 500,
+                Status = AccountStatus.Live,
+                AllowedPaymentSchemes = allowedPaymentSchemes
+            };
+            var request = new MakePaymentRequest
+            {
+                DebtorAccountNumber = "12345678",
+                Amount = 100,
+                PaymentScheme = paymentScheme
+            };
+            _accountDataStoreMock.Setup(x => x.GetAccount(request.DebtorAccountNumber)).Returns(account);
+            // Act
+            var result = paymentService.MakePayment(request);
+            // Assert
+            Assert.True(result.Success);
+        }
+
+        [Theory]
+        [InlineData(PaymentScheme.Chaps, AllowedPaymentSchemes.Bacs)]
+        [InlineData(PaymentScheme.Bacs, AllowedPaymentSchemes.FasterPayments)]
+        [InlineData(PaymentScheme.FasterPayments, AllowedPaymentSchemes.Chaps)]
+        [InlineData(PaymentScheme.Bacs, AllowedPaymentSchemes.Chaps | AllowedPaymentSchemes.FasterPayments)]
+        [InlineData(PaymentScheme.Chaps, AllowedPaymentSchemes.Bacs | AllowedPaymentSchemes.FasterPayments)]
+        public void MakePayment_ShouldReturnFalse_WhenAccountIsActive_AndHasIncorrectPaymentScheme(PaymentScheme paymentScheme, AllowedPaymentSchemes allowedPaymentSchemes)
+        {
+            // Arrange
+            var paymentService = new PaymentService(_accountDataStoreMock.Object, _loggerMock.Object);
+
+            var account = new Account
+            {
+                AccountNumber = "12345678",
+                Balance = 500,
+                Status = AccountStatus.Live,
+                AllowedPaymentSchemes = allowedPaymentSchemes
+            };
+            var request = new MakePaymentRequest
+            {
+                DebtorAccountNumber = "12345678",
+                Amount = 100,
+                PaymentScheme = paymentScheme
+            };
+            _accountDataStoreMock.Setup(x => x.GetAccount(request.DebtorAccountNumber)).Returns(account);
+            // Act
+            var result = paymentService.MakePayment(request);
+            // Assert
+            Assert.False(result.Success);
+        }
+    }
+}

ClearBank.DeveloperTest/ClearBank.DeveloperTest.csproj

@@ -1,11 +1,13 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk.Web">
 
   <PropertyGroup>
     <TargetFramework>net8.0</TargetFramework>
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="System.Configuration.ConfigurationManager" Version="8.0.0" />
+    <PackageReference Include="Swashbuckle.AspNetCore" Version="6.6.2" />
   </ItemGroup>
 
-</Project>
+</Project>

ClearBank.DeveloperTest/Controllers/PaymentServiceController.cs

@@ -0,0 +1,24 @@
+using ClearBank.DeveloperTest.Services;
+using ClearBank.DeveloperTest.Types;
+using Microsoft.AspNetCore.Mvc;
+using System.Threading.Tasks;
+
+namespace ClearBank.DeveloperTest.Controllers
+{
+    [ApiController]
+    [Route("[controller]")]
+    public class PaymentServiceController : ControllerBase
+    {
+        private readonly IPaymentService _paymentService;
+        public PaymentServiceController(IPaymentService paymentService)
+        {
+            _paymentService = paymentService;
+        }
+
+        [HttpPost]
+        public MakePaymentResult Post(MakePaymentRequest request)
+        {
+            return _paymentService.MakePayment(request);
+        }
+    }
+}

ClearBank.DeveloperTest/Data/AccountDataStore.cs

@@ -2,8 +2,13 @@
 
 namespace ClearBank.DeveloperTest.Data
 {
-    public class AccountDataStore
+    public class AccountDataStore : IAccountDataStore
     {
+        public AccountDataStore()
+        {
+            // I'd add here the database context, or the account service provided its an external service
+        }
+
         public Account GetAccount(string accountNumber)
         {
             // Access database to retrieve account, code removed for brevity 

ClearBank.DeveloperTest/Data/BackupAccountDataStore.cs

@@ -2,8 +2,13 @@
 
 namespace ClearBank.DeveloperTest.Data
 {
-    public class BackupAccountDataStore
+    public class BackupAccountDataStore : IAccountDataStore
     {
+        public BackupAccountDataStore()
+        {
+            // I'd add here the backup database context if needed, or the backup account service provided its an external service
+        }
+
         public Account GetAccount(string accountNumber)
         {
             // Access backup data base to retrieve account, code removed for brevity 

ClearBank.DeveloperTest/Data/IAccountDataStore.cs

@@ -0,0 +1,11 @@
+using ClearBank.DeveloperTest.Types;
+
+namespace ClearBank.DeveloperTest.Data
+{
+    public interface IAccountDataStore
+    {
+        Account GetAccount(string accountNumber);
+
+        void UpdateAccount(Account account);
+    }
+}

ClearBank.DeveloperTest/Program.cs

@@ -0,0 +1,42 @@
+using ClearBank.DeveloperTest.Services;
+using ClearBank.DeveloperTest.Data;
+using ClearBank.DeveloperTest.Types;
+
+var builder = WebApplication.CreateBuilder(args);
+
+// Add services to the container.
+
+builder.Services.AddControllers();
+// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
+builder.Services.AddEndpointsApiExplorer();
+builder.Services.AddSwaggerGen();
+builder.Services.AddLogging();
+
+bool useBackupDataStore = (bool)builder.Configuration.GetValue(typeof(bool), "UseBackupDataStore");
+if (useBackupDataStore)
+{
+    builder.Services.AddSingleton<IAccountDataStore, BackupAccountDataStore>();
+}
+else
+{
+    builder.Services.AddSingleton<IAccountDataStore, AccountDataStore>();
+}
+
+builder.Services.AddScoped<IPaymentService, PaymentService>();
+
+var app = builder.Build();
+
+// Configure the HTTP request pipeline.
+if (app.Environment.IsDevelopment())
+{
+    app.UseSwagger();
+    app.UseSwaggerUI();
+}
+
+app.UseHttpsRedirection();
+
+app.UseAuthorization();
+
+app.MapControllers();
+
+app.Run();