Refactor exception handling

Author: Ahmad El Lahib

src/CourseLibrary/CourseLibrary.API/Brokers/Caches/CacheBroker.Categories.cs

@@ -7,9 +7,9 @@ public partial class CacheBroker
 {
     private const string CategoriesCacheKey = "CategoriesCacheKey";
 
-    public List<Category> GetCachedCategories()
+    public List<Category>? GetCachedCategories()
     {
-        return GetCache<List<Category>>(CategoriesCacheKey);
+        return GetCache<List<Category>?>(CategoriesCacheKey);
     }
 
     public void SetCachedCategories(List<Category> categoriesList)

src/CourseLibrary/CourseLibrary.API/Brokers/Caches/ICacheBroker.Categories.cs

@@ -4,7 +4,7 @@ namespace CourseLibrary.API.Brokers.Caches;
 
 public partial interface ICacheBroker
 {
-    List<Category> GetCachedCategories();
+    List<Category>? GetCachedCategories();
     void SetCachedCategories(List<Category> categoriesList);
     void ClearCachedCategories();
 }

src/CourseLibrary/CourseLibrary.API/Brokers/Loggings/ILoggingBroker.cs

@@ -10,9 +10,9 @@ public interface ILoggingBroker<T> where T : class
 
     void LogInformation(string message, params object?[] args);
 
-    void LogWarning(string message);
+    void LogWarning(string message, params object?[] args);
 
-    void LogError(Exception exception);
+    void LogError(Exception exception, string instance);
 
-    void LogCritical(Exception exception);
+    void LogCritical(string instance, Exception exception);
 }

src/CourseLibrary/CourseLibrary.API/Brokers/Loggings/LoggingBroker.cs

@@ -21,12 +21,12 @@ public void LogTrace(string message) =>
     public void LogInformation(string message, params object?[] args) =>
         _logger.LogInformation(message, args);
 
-    public void LogWarning(string message) =>
-        _logger.LogWarning(message);
+    public void LogWarning(string message, params object?[] args) =>
+        _logger.LogWarning(message, args);
 
-    public void LogError(Exception exception)
+    public void LogError(Exception exception, string instance)
     {
-        StringBuilder sb = new($"{exception.Message}{Environment.NewLine}");
+        StringBuilder sb = new($"{instance} {exception.Message}{Environment.NewLine}");
 
         if (exception.InnerException != null)
         {
@@ -36,29 +36,14 @@ public void LogError(Exception exception)
             {
                 sb.AppendLine(exception.InnerException.InnerException.Message);
             }
-
-            foreach (object? key in exception.InnerException.Data.Keys)
-            {
-                string keyMessage = $"   {key}: ";
-                sb.AppendLine(keyMessage);
-
-                List<string>? list = exception.InnerException.Data[key] as List<string>;
-                if (list is not null)
-
-                    for (int i = 0; i < list.Count; i++)
-                    {
-                        string? value = list[i];
-                        sb.AppendLine($"        {value}");
-                    }
-            }
         }
 
         _logger.LogError(sb.ToString(), exception);
     }
 
-    public void LogCritical(Exception exception)
+    public void LogCritical(string instance, Exception exception)
     {
-        StringBuilder sb = new($"{exception.Message}");
+        StringBuilder sb = new($"{instance} {exception.Message}{Environment.NewLine}");
 
         if (exception.InnerException != null)
         {
@@ -70,6 +55,8 @@ public void LogCritical(Exception exception)
             }
         }
 
+        sb.Append($"{Environment.NewLine}StackTrace: {exception.StackTrace}");
+
         _logger.LogCritical(exception, sb.ToString());
     }
 }

src/CourseLibrary/CourseLibrary.API/Controllers/V1/AuthorsController.cs

@@ -1,7 +1,6 @@
 using CourseLibrary.API.Contracts.Authors;
 using CourseLibrary.API.Filters;
 using CourseLibrary.API.Models.Authors;
-using CourseLibrary.API.Models.Exceptions;
 using CourseLibrary.API.Pagination;
 using CourseLibrary.API.Services.V1.Authors;
 using Microsoft.AspNetCore.Mvc;
@@ -31,16 +30,9 @@ public AuthorsController(IAuthorOrchestrationService authorOrchestrationService)
     [ProducesResponseType(typeof(string), StatusCodes.Status500InternalServerError)]
     public async ValueTask<IActionResult> GetAuthorAsync([FromRoute] Guid authorId, [FromServices] IOptions<ApiBehaviorOptions> apiBehaviorOptions, CancellationToken cancellationToken)
     {
-        try
-        {
-            Author author = await _authorOrchestrationService.RetrieveAuthorByIdAsync(authorId, cancellationToken);
+        Author author = await _authorOrchestrationService.RetrieveAuthorByIdAsync(authorId, cancellationToken);
 
-            return Ok((AuthorDto)author);
-        }
-        catch (Exception exception)
-        {
-            return HandleException(exception, apiBehaviorOptions, ControllerContext);
-        }
+        return Ok((AuthorDto)author);
     }
 
     [HttpPost]
@@ -52,16 +44,9 @@ public async ValueTask<IActionResult> GetAuthorAsync([FromRoute] Guid authorId,
     [ProducesResponseType(typeof(string), StatusCodes.Status500InternalServerError)]
     public async Task<IActionResult> PostAuthorAsync([FromBody] AuthorForCreation authorForCreation, [FromServices] IOptions<ApiBehaviorOptions> apiBehaviorOptions, CancellationToken cancellationToken)
     {
-        try
-        {
-            Author addedAuthor = await _authorOrchestrationService.CreateAuthorAsync((Author)authorForCreation, cancellationToken);
+        Author addedAuthor = await _authorOrchestrationService.CreateAuthorAsync((Author)authorForCreation, cancellationToken);
 
-            return CreatedAtRoute(nameof(GetAuthorAsync), new { authorId = addedAuthor.Id }, (AuthorCreatedDto)addedAuthor);
-        }
-        catch (Exception exception)
-        {
-            return HandleException(exception, apiBehaviorOptions, ControllerContext);
-        }
+        return CreatedAtRoute(nameof(GetAuthorAsync), new { authorId = addedAuthor.Id }, (AuthorCreatedDto)addedAuthor);
     }
 
     [HttpPatch("{authorId}")]
@@ -73,18 +58,11 @@ public async Task<IActionResult> PostAuthorAsync([FromBody] AuthorForCreation au
     [ProducesResponseType(typeof(string), StatusCodes.Status500InternalServerError)]
     public async Task<IActionResult> PatchAuthorAsync([FromRoute] Guid authorId, [FromBody] AuthorForUpdate authorForUpdate, [FromServices] IOptions<ApiBehaviorOptions> apiBehaviorOptions, CancellationToken cancellationToken)
     {
-        try
-        {
-            Author author = (Author)authorForUpdate;
-            author.Id = authorId;
-            Author storageAuthor = await _authorOrchestrationService.ModifyAuthorAsync(author, cancellationToken);
+        Author author = (Author)authorForUpdate;
+        author.Id = authorId;
+        Author storageAuthor = await _authorOrchestrationService.ModifyAuthorAsync(author, cancellationToken);
 
-            return Ok((AuthorUpdatedDto)storageAuthor);
-        }
-        catch (Exception exception)
-        {
-            return HandleException(exception, apiBehaviorOptions, ControllerContext);
-        }
+        return Ok((AuthorUpdatedDto)storageAuthor);
     }
 
     [HttpDelete("{authorId}")]
@@ -95,16 +73,9 @@ public async Task<IActionResult> PatchAuthorAsync([FromRoute] Guid authorId, [Fr
     [ProducesResponseType(typeof(string), StatusCodes.Status500InternalServerError)]
     public async Task<IActionResult> DeleteAuthorAsync(Guid authorId, [FromServices] IOptions<ApiBehaviorOptions> apiBehaviorOptions, CancellationToken cancellationToken)
     {
-        try
-        {
-            await _authorOrchestrationService.RemoveAuthorByIdAsync(authorId, cancellationToken);
+        await _authorOrchestrationService.RemoveAuthorByIdAsync(authorId, cancellationToken);
 
-            return NoContent();
-        }
-        catch (Exception exception)
-        {
-            return HandleException(exception, apiBehaviorOptions, ControllerContext);
-        }
+        return NoContent();
     }
 
     [HttpGet(Name = nameof(SearchAuthorsAsync))]
@@ -113,37 +84,25 @@ public async Task<IActionResult> DeleteAuthorAsync(Guid authorId, [FromServices]
     [ProducesResponseType(typeof(string), StatusCodes.Status500InternalServerError)]
     public ActionResult<IEnumerable<AuthorDto>> SearchAuthorsAsync([FromQuery] AuthorResourceParameters authorResourceParameters)
     {
-        try
-        {
-            PagedList<Author> storagePagedAuthors = _authorOrchestrationService.SearchAuthors(authorResourceParameters);
-
-            PaginationMetaData PaginationMetaData = new()
-            {
-                TotalCount = storagePagedAuthors.TotalCount,
-                PageSize = storagePagedAuthors.PageSize,
-                CurrentPage = storagePagedAuthors.CurrentPage,
-                TotalPages = storagePagedAuthors.TotalPages,
-                HasPrevious = storagePagedAuthors.HasPrevious,
-                HasNext = storagePagedAuthors.HasNext,
-                PreviousPageLink = storagePagedAuthors.HasPrevious ? CreateAuthorResourceUri(authorResourceParameters, ResourceUriType.PreviousPage) : string.Empty,
-                NextPageLink = storagePagedAuthors.HasNext ? CreateAuthorResourceUri(authorResourceParameters, ResourceUriType.NextPage) : string.Empty
-            };
-
-            Response.Headers.Add("X-Pagination", JsonSerializer.Serialize(PaginationMetaData));
-
-            List<AuthorDto> authorsDtos = new();
-
-            foreach (Author author in storagePagedAuthors)
-            {
-                authorsDtos.Add((AuthorDto)author);
-            }
-
-            return Ok(authorsDtos);
-        }
-        catch (Exception exception)
+        PagedList<Author> storagePagedAuthors = _authorOrchestrationService.SearchAuthors(authorResourceParameters);
+
+        PaginationMetaData paginationMetaData = new()
         {
-            return (ActionResult)HandleException(exception);
-        }
+            TotalCount = storagePagedAuthors.TotalCount,
+            PageSize = storagePagedAuthors.PageSize,
+            CurrentPage = storagePagedAuthors.CurrentPage,
+            TotalPages = storagePagedAuthors.TotalPages,
+            HasPrevious = storagePagedAuthors.HasPrevious,
+            HasNext = storagePagedAuthors.HasNext,
+            PreviousPageLink = storagePagedAuthors.HasPrevious ? CreateAuthorResourceUri(authorResourceParameters, ResourceUriType.PreviousPage) : string.Empty,
+            NextPageLink = storagePagedAuthors.HasNext ? CreateAuthorResourceUri(authorResourceParameters, ResourceUriType.NextPage) : string.Empty
+        };
+
+        Response.Headers.Append("X-Pagination", JsonSerializer.Serialize(paginationMetaData));
+
+        List<AuthorDto> authorsDto = storagePagedAuthors.Select(author => (AuthorDto)author).ToList();
+
+        return Ok(authorsDto);
     }
 
     private string CreateAuthorResourceUri(AuthorResourceParameters authorResourceParameters, ResourceUriType type)
@@ -188,33 +147,4 @@ private string CreateAuthorResourceUri(AuthorResourceParameters authorResourcePa
 
         return resourceUri is null ? string.Empty : resourceUri.Replace("http://", "https://");
     }
-
-    private IActionResult HandleException(Exception exception, IOptions<ApiBehaviorOptions>? apiBehaviorOptions = null, ActionContext? actionContext = null)
-    {
-        switch (exception)
-        {
-            case ResourceParametersException:
-                return BadRequest(exception.Message);
-            case CancellationException:
-                return NoContent();
-            case ValidationException when exception.InnerException is NotFoundEntityException<Author>:
-                return NotFound(GetInnerMessage(exception));
-            case ValidationException:
-                if (apiBehaviorOptions is null || actionContext is null)
-                    throw new ArgumentNullException(nameof(apiBehaviorOptions));
-
-                SetModelState(ModelState, (ValidationException)exception);
-
-                return apiBehaviorOptions!.Value.InvalidModelStateResponseFactory(actionContext!);
-            case IDependencyException when (exception.InnerException is DbConflictException):
-                return Conflict(exception.Message);
-            case IDependencyException when (exception.InnerException is LockedEntityException<Author>):
-                return Problem(GetInnerMessage(exception));
-            case IServiceException:
-                return Problem(StaticData.ControllerMessages.InternalServerError);
-            default:
-                LoggingBroker.LogError(exception);
-                return Problem(StaticData.ControllerMessages.InternalServerError);
-        }
-    }
 }