feat: paginate response of get-all-transactions api

src/Application/DTOs/PaginatedList.cs

@@ -0,0 +1,21 @@
+namespace Application.DTOs;
+
+public class PaginatedList<T>
+{
+    public List<T> Items { get; }
+    public int TotalCount { get; }
+    public int PageNumber { get; }
+    public int PageSize { get; }
+    public int TotalPages => (int)Math.Ceiling(TotalCount / (double)PageSize);
+
+    public PaginatedList(List<T> items, int count, int pageNumber, int pageSize)
+    {
+        Items = items;
+        TotalCount = count;
+        PageNumber = pageNumber;
+        PageSize = pageSize;
+    }
+
+    public bool HasPreviousPage => PageNumber > 1;
+    public bool HasNextPage => PageNumber < TotalPages;
+}

src/Application/Interfaces/Repositories/ITransactionRepository.cs

@@ -5,8 +5,9 @@ namespace Application.Interfaces.Repositories;
 public interface ITransactionRepository
 {
     Task CreateBulkAsync(List<Transaction> transactions);
-    Task<List<Transaction>> GetAllTransactions();
+    Task<List<Transaction>> GetAllTransactions(int skip, int take);
     Task<List<Transaction>> GetBySourceAccountId(long accountId);
     Task<List<Transaction>> GetByDestinationAccountId(long accountId);
     Task<List<long>> GetAllIdsAsync();
+    Task<int> CountAllTransactionsAsync();
 }

src/Application/Interfaces/Services/ITransactionService.cs

@@ -7,6 +7,6 @@ namespace Application.Interfaces.Services;
 public interface ITransactionService
 {
     Task<Result> AddTransactionsFromCsvAsync(string filePath);
-    Task<Result<List<Transaction>>> GetAllTransactionsAsync();
+    Task<Result<PaginatedList<Transaction>>> GetAllTransactionsAsync(int pageNumber, int pageSize);
     Task<Result<List<GetTransactionsByAccountIdResponse>>> GetTransactionsByAccountIdAsync(long accountId);
 }

src/Application/Services/DomainService/TransactionService.cs

@@ -39,16 +39,21 @@ public async Task<Result> AddTransactionsFromCsvAsync(string filePath)
         }
     }
 
-    public async Task<Result<List<Transaction>>> GetAllTransactionsAsync()
+    public async Task<Result<PaginatedList<Transaction>>> GetAllTransactionsAsync(int pageNumber, int pageSize)
     {
         try
         {
-            var transactions = await _transactionRepository.GetAllTransactions();
-            return Result<List<Transaction>>.Ok(transactions);
+            var skip = (pageNumber - 1) * pageSize;
+            var transactions = await _transactionRepository.GetAllTransactions(skip, pageSize);
+            var totalTransactions = await _transactionRepository.CountAllTransactionsAsync();
+
+            var paginatedTransactions = new PaginatedList<Transaction>(transactions, totalTransactions, pageNumber, pageSize);
+
+            return Result<PaginatedList<Transaction>>.Ok(paginatedTransactions);
         }
         catch (Exception ex)
         {
-            return Result<List<Transaction>>.Fail($"An error occurred: {ex.Message}");
+            return Result<PaginatedList<Transaction>>.Fail($"An error occurred: {ex.Message}");
         }
     }
 

src/Application/Services/SharedService/PaginatorService.cs

@@ -0,0 +1,16 @@
+using Application.DTOs;
+
+namespace Application.Services.SharedService;
+
+public static class PaginatorService
+{
+    public static PaginatedList<T> Paginate<T>(this IEnumerable<T> source, int pageNumber, int pageSize)
+    {
+        var sourceList = source as IList<T> ?? source.ToList();
+
+        var count = sourceList.Count;
+        var items = sourceList.Skip((pageNumber - 1) * pageSize).Take(pageSize).ToList();
+
+        return new PaginatedList<T>(items, count, pageNumber, pageSize);
+    }
+}

src/Infrastructure/Repositories/TransactionRepository.cs

@@ -19,9 +19,13 @@ public async Task CreateBulkAsync(List<Transaction> transactions)
         await _dbContext.SaveChangesAsync();
     }
 
-    public async Task<List<Transaction>> GetAllTransactions()
+    public async Task<List<Transaction>> GetAllTransactions(int skip, int take)
     {
-        return await _dbContext.Transactions.ToListAsync();
+        return await _dbContext.Transactions
+            .OrderBy(t => t.TransactionId)
+            .Skip(skip)
+            .Take(take)
+            .ToListAsync();
     }
 
     public Task<List<Transaction>> GetBySourceAccountId(long accountId)
@@ -44,4 +48,9 @@ public async Task<List<long>> GetAllIdsAsync()
             .Select(a => a.TransactionId)
             .ToListAsync();
     }
+
+    public async Task<int> CountAllTransactionsAsync()
+    {
+        return await _dbContext.Transactions.CountAsync();
+    }
 }

src/Web/Controllers/TransactionsController.cs

@@ -56,9 +56,9 @@ public async Task<IActionResult> UploadTransactions([FromForm] IFormFile file)
     [ProducesResponseType(400)]
     [ProducesResponseType(401)]
     [ProducesResponseType(403)]
-    public async Task<IActionResult> GetAllTransactions()
+    public async Task<IActionResult> GetAllTransactions(int pageNumber = 1, int pageSize = 30)
     {
-        var allTransactions = await _transactionService.GetAllTransactionsAsync();
+        var allTransactions = await _transactionService.GetAllTransactionsAsync(pageNumber, pageSize);
         if (!allTransactions.Succeed)
         {
             var errorResponse = Errors.New(nameof(GetAllTransactions), allTransactions.Message);

src/Web/Mappers/TransactionMapper.cs

@@ -1,3 +1,4 @@
+using Application.DTOs;
 using Domain.Entities;
 using Web.DTOs.Transaction;
 
@@ -17,10 +18,10 @@ public static TransactionDto ToTransactionDto(this Transaction transaction)
             Type = transaction.Type 
         };
     }
-
-    public static List<TransactionDto> ToGotAllTransactionsDto(this List<Transaction> transactions)
+    
+    public static PaginatedList<TransactionDto> ToGotAllTransactionsDto(this PaginatedList<Transaction> transactions)
     {
-        return transactions.Select(transaction => new TransactionDto
+        var dtoItems = transactions.Items.Select(transaction => new TransactionDto
         {
             TransactionId = transaction.TransactionId,
             SourceAccountId = transaction.SourceAccountId,
@@ -29,5 +30,8 @@ public static List<TransactionDto> ToGotAllTransactionsDto(this List<Transaction
             Date = transaction.Date,
             Type = transaction.Type
         }).ToList();
+
+        return new PaginatedList<TransactionDto>(dtoItems, transactions.TotalCount, transactions.PageNumber, transactions.PageSize);
     }
+
 }