public void Initialize()
{
using (CustomersContext context = new CustomersContext())
{
context.Database.CreateIfNotExists();
}
}
public void Cleanup()
{
using (CustomersContext context = new CustomersContext())
{
if (context.Database.Exists())
{
context.Database.Delete();
}
}
}
public void InvalidCustomerIsNotAddedToDb()
{
// Add invalid customer to DB.
Customer customer = TestHelpers.GetSampleCustomer();
customer.Name = TestHelpers.STRING_LONGER_THAN_50_CHARS;
DataProxy dataProxy = new DataProxy();
DateTime? result = dataProxy.AddCustomer(customer).Result;
// Connect to CustomersContext to check if it exists in the DB.
using (CustomersContext context = new CustomersContext())
{
bool exists = context.CustomerDbs.Any(c => c.Id == customer.Id);
Assert.IsFalse(exists);
}
}
/// <summary>
/// Retries the customers data from the database.
/// </summary>
/// <returns>Collection of the customers.</returns>
public async Task<List<Customer>> GetCustomers()
{
try
{
using (CustomersContext context = new CustomersContext())
{
List<CustomerDb> customersDb = await context.CustomerDbs.ToListAsync();
List<Customer> customers = customersDb
.Select(cdb =>
{
Customer c = new Customer()
{
Id = cdb.Id,
AddressLineOne = cdb.AddressLineOne,
Category = cdb.Category,
Country = cdb.Country,
DateOfBirth = cdb.DateOfBirth,
Gender = cdb.Gender,
HouseNumber = cdb.HouseNumber,
Name = cdb.Name,
State = cdb.State,
};
return c;
}
).ToList();
return customers;
}
}
catch (InvalidCastException e)
{
DbLog.LogException(e, "DataProxy.cs");
throw;
}
catch (InvalidOperationException e)
{
DbLog.LogException(e, "DataProxy.cs");
throw;
}
}
/// <summary>
/// Adds the customer to the database.
/// </summary>
/// <param name="customer">The customer to be added.</param>
/// <param name="cancellationToken">Cancellation token to cancel save.</param>
/// <returns>If successful returns datetime of the add operation, otherwise null.</returns>
public async Task<Nullable<DateTime>> AddCustomer(Customer customer, CancellationToken cancellationToken = new CancellationToken())
{
try
{
if (customer == null)
{
throw new ArgumentNullException("Null Customer cannot be added");
}
if (!customer.IsValid)
{
return null;
}
using (CustomersContext context = new CustomersContext())
{
CustomerDb customerDb = new CustomerDb()
{
AddressLineOne = customer.AddressLineOne,
Category = customer.Category,
Country = customer.Country,
DateOfBirth = customer.DateOfBirth,
Gender = customer.Gender,
HouseNumber = customer.HouseNumber,
Name = customer.Name,
State = customer.State
};
context.CustomerDbs.Add(customerDb);
await context.SaveChangesAsync(cancellationToken);
if (!cancellationToken.IsCancellationRequested)
{
// The Id is created by the database so before
// logging modification history entry update the customer with the new Id.
customer.Id = customerDb.Id;
await EnterModificationHistory(context, customer, ModificationType.Add);
this.lastDataBaseModificationTime = DateTime.Now;
return this.lastDataBaseModificationTime;
}
return null;
}
}
catch (InvalidOperationException e)
{
DbLog.LogException(e, "DataProxy.cs");
throw;
}
catch (NullReferenceException e)
{
DbLog.LogException(e, "DataProxy.cs");
throw;
}
catch (OperationCanceledException)
{
throw;
}
catch (Exception)
{
// Cancelletion exception can be wrapped in several other exceptions.
// Instead of unwrapping it check if cancellation requested.
if (cancellationToken.IsCancellationRequested)
{
throw new OperationCanceledException();
}
throw;
}
}
/// <summary>
/// Enteres a modification history entry based on the submitted customer and the modification type.
/// </summary>
/// <param name="context">The context in which the modification entry will be performed.</param>
/// <param name="customer">The customer object that has been modified. Original details are saved in the history table.</param>
/// <param name="modificationType">The modofication type: Add, Remove, Update, Other</param>
/// <returns></returns>
private async Task EnterModificationHistory(CustomersContext context, Customer customer, ModificationType modificationType)
{
CustomerDbHistory customerHistory = new CustomerDbHistory()
{
// log modification type
ModificationType = modificationType,
// and customer details so it's easier to reproduce changes
Id = customer.Id,
AddressLineOne = customer.AddressLineOne,
Category = customer.Category,
Country = customer.Country,
DateOfBirth = customer.DateOfBirth,
Gender = customer.Gender,
HouseNumber = customer.HouseNumber,
Name = customer.Name,
State = customer.State,
ChangedOn = DateTime.Now.ToString("MM/dd/yyyy hh:mm:ss.fff tt")
};
try
{
context.CustomerDbHistories.Add(customerHistory);
await context.SaveChangesAsync();
}
catch (Exception e)
{
DbLog.LogException(e, "DataProxy.cs");
}
}
/// <summary>
/// Crates the modification history of all changes in the database.
/// Order by modification time, in descending order.
/// </summary>
/// <returns>String containing description of all modifications in csv format.</returns>
public async Task<string> GetModificationHistory()
{
try
{
using (CustomersContext context = new CustomersContext())
{
StringBuilder modificationHistory = new StringBuilder();
// Pass empty item to the method to get headers.
modificationHistory.AppendLine(CustomerHistoryToCsvHeaders(new CustomerDbHistory()));
List<CustomerDbHistory> customers = await (context.CustomerDbHistories.OrderByDescending(ch => ch.ChangedOn)).ToListAsync();
foreach (CustomerDbHistory entry in customers)
{
modificationHistory.AppendLine(CustomerHistoryToCsv(entry));
}
return modificationHistory.ToString();
}
}
catch (InvalidOperationException e)
{
DbLog.LogException(e, "DataProxy.cs");
throw;
}
catch (ArgumentNullException e)
{
DbLog.LogException(e, "DataProxy.cs");
throw;
}
}
/// <summary>
/// Removes the customer from the database.
/// </summary>
/// <param name="customer">The customer to be removed.</param>
/// <returns>If successful returns datetime of the remove operation, otherwise null.</returns>
public async Task<Nullable<DateTime>> RemoveCustomer(Customer customer)
{
try
{
if (customer == null)
{
throw new ArgumentNullException("Null Customer cannot be updated.");
}
using (CustomersContext context = new CustomersContext())
{
CustomerDb customerDb = context.CustomerDbs.FirstOrDefault(c => c.Id == customer.Id);
if (customerDb == null)
{
return null;
}
context.CustomerDbs.Remove(customerDb);
await context.SaveChangesAsync();
await EnterModificationHistory(context, customer, ModificationType.Remove);
this.lastDataBaseModificationTime = DateTime.Now;
return this.lastDataBaseModificationTime;
}
}
catch (InvalidOperationException e)
{
DbLog.LogException(e, "DataProxy.cs");
throw;
}
catch (NullReferenceException e)
{
DbLog.LogException(e, "DataProxy.cs");
throw;
}
}
/// <summary>
/// Updates the customer in the database
/// </summary>
/// <param name="customer">The customer to be updated.</param>
/// <param name="cancellationToken">Cancellation token to cancel save.</param>
/// <returns>If successful returns datetime of the update operation, otherwise null.</returns>
public async Task<Nullable<DateTime>> UpdateCustomer(Customer customer, CancellationToken cancellationToken = new CancellationToken())
{
try
{
if (customer == null)
{
throw new ArgumentNullException("Null Customer cannot be updated.");
}
if (!customer.IsValid)
{
return null;
}
using (CustomersContext context = new CustomersContext())
{
CustomerDb customerDb = context.CustomerDbs.Find(customer.Id);
if (customerDb == null)
{
return null;
}
customerDb.AddressLineOne = customer.AddressLineOne;
customerDb.Category = customer.Category;
customerDb.Country = customer.Country;
customerDb.DateOfBirth = customer.DateOfBirth;
customerDb.Gender = customer.Gender;
customerDb.HouseNumber = customer.HouseNumber;
customerDb.Name = customer.Name;
customerDb.State = customer.State;
await context.SaveChangesAsync(cancellationToken);
if (!cancellationToken.IsCancellationRequested)
{
await EnterModificationHistory(context, customer, ModificationType.Update);
this.lastDataBaseModificationTime = DateTime.Now;
return this.lastDataBaseModificationTime;
}
return null;
}
}
catch (InvalidOperationException e)
{
DbLog.LogException(e, "DataProxy.cs");
throw;
}
catch (NullReferenceException e)
{
DbLog.LogException(e, "DataProxy.cs");
throw;
}
catch (OperationCanceledException)
{
throw;
}
catch (Exception)
{
// Cancelletion exception can be wrapped in several other exceptions.
// Instead of unwrapping it check if cancellation requested.
if (cancellationToken.IsCancellationRequested)
{
throw new OperationCanceledException();
}
throw;
}
}
public void ValidCustomerIsSuccessfullyAddedToDb2()
{
// Add customer to DB.
Customer customer = TestHelpers.GetSampleCustomer();
DataProxy dataProxy = new DataProxy();
DateTime? result = dataProxy.AddCustomer(customer).Result;
// Connect to CustomersContext to check if it exists in the DB.
using (CustomersContext context = new CustomersContext())
{
bool exists = context.CustomerDbs.Any(c => c.Id == customer.Id);
Assert.IsTrue(exists);
}
}
public void UpdatingExistingUserWithValidDataIsSuccessful()
{
Customer customer = TestHelpers.GetSampleCustomer();
DataProxy dataProxy = new DataProxy();
DateTime? result = dataProxy.AddCustomer(customer).Result;
customer.Name = "New Name";
DateTime? updateResult = dataProxy.UpdateCustomer(customer).Result;
Assert.IsNotNull(updateResult);
// Check database if the user with id has specified name
using (CustomersContext context = new CustomersContext())
{
bool existsWithUpdatedName = context.CustomerDbs
.Any(c => c.Id == customer.Id && c.Name == customer.Name);
Assert.IsTrue(existsWithUpdatedName);
}
}
public void UpdatingExistingUserWithInvalidDataFails()
{
Customer customer = TestHelpers.GetSampleCustomer();
DataProxy dataProxy = new DataProxy();
DateTime? result = dataProxy.AddCustomer(customer).Result;
customer.Name = TestHelpers.STRING_LONGER_THAN_50_CHARS;
DateTime? updateResult = dataProxy.UpdateCustomer(customer).Result;
Assert.IsNull(updateResult);
// Check database if the user with id has specified name
using (CustomersContext context = new CustomersContext())
{
bool existsWithUpdatedName = context.CustomerDbs
.Any(c => c.Id == customer.Id && c.Name == customer.Name);
Assert.IsFalse(existsWithUpdatedName);
}
}