Added new query results (#91)

Author: adimiko

source/EasyWay.WebApi/Internals/WebApiResultMapper.cs

@@ -18,7 +18,7 @@ public IResult Map(CommandResult commandResult)
                 CommandErrorEnum.OperationCanceled => Results.StatusCode(499),
                 CommandErrorEnum.NotFound => Results.StatusCode(404),
                 CommandErrorEnum.Forbidden => Results.StatusCode(404),
-                _ => Results.StatusCode(500),
+                CommandErrorEnum.UnknownException or _ => Results.StatusCode(500),
             };
         }
 
@@ -33,7 +33,7 @@ public IResult Map<TOperationResult>(CommandResult<TOperationResult> commandResu
                 CommandErrorEnum.OperationCanceled => Results.StatusCode(499),
                 CommandErrorEnum.NotFound => Results.StatusCode(404),
                 CommandErrorEnum.Forbidden => Results.StatusCode(404),
-                _ => Results.StatusCode(500),
+                CommandErrorEnum.UnknownException or _ => Results.StatusCode(500),
             };
         }
 
@@ -43,9 +43,10 @@ public IResult Map<TReadModel>(QueryResult<TReadModel> queryResult) where TReadM
             {
                 QueryErrorEnum.None => Results.Ok(queryResult.ReadModel),
                 QueryErrorEnum.Validation => Results.BadRequest(queryResult.ValidationErrors),
+                QueryErrorEnum.OperationCanceled => Results.StatusCode(499),
                 QueryErrorEnum.NotFound => Results.StatusCode(404),
                 QueryErrorEnum.Forbidden => Results.StatusCode(404),
-                _ => Results.StatusCode(500),
+                QueryErrorEnum.UnknownException or _ => Results.StatusCode(500),
             };
         }
     }

source/EasyWay/Internals/Queries/QueryExecutor.cs

@@ -12,7 +12,7 @@ public QueryExecutor(IServiceProvider serviceProvider)
             _serviceProvider = serviceProvider;
         }  
 
-        public Task<QueryResult<TReadModel>> Execute<TModule, TQuery, TReadModel>(TQuery query, CancellationToken cancellationToken = default)
+        public async Task<QueryResult<TReadModel>> Execute<TModule, TQuery, TReadModel>(TQuery query, CancellationToken cancellationToken = default)
             where TModule : EasyWayModule
             where TQuery : Query<TReadModel>
             where TReadModel : ReadModel
@@ -27,11 +27,26 @@ public Task<QueryResult<TReadModel>> Execute<TModule, TQuery, TReadModel>(TQuery
 
                 if (errors.Any())
                 {
-                    return Task.FromResult(QueryResult<TReadModel>.Validation(errors));
+                    return QueryResult<TReadModel>.Validation(errors);
                 }
             }
 
-            return _serviceProvider.GetRequiredService<QueryHandler<TQuery, TReadModel>>().Handle(query);
+            QueryResult<TReadModel> result;
+
+            try
+            {
+                result = await _serviceProvider.GetRequiredService<QueryHandler<TQuery, TReadModel>>().Handle(query);
+            }
+            catch (OperationCanceledException)
+            {
+                return QueryResult<TReadModel>.OperationCanceled();
+            }
+            catch (Exception exception)
+            {
+                return QueryResult<TReadModel>.UnknownException(exception);
+            }
+
+            return result;
         }
     }
 }

source/EasyWay/Internals/Queries/Results/QueryErrorEnum.cs

@@ -1,10 +1,12 @@
 namespace EasyWay.Internals.Queries.Results
 {
-    internal enum QueryErrorEnum
+    internal enum QueryErrorEnum : byte
     {
-        None,
-        Validation,
-        NotFound,
-        Forbidden,
+        None = 1,
+        Validation = 2,
+        NotFound = 3,
+        Forbidden = 4,
+        OperationCanceled = 5,
+        UnknownException = 6
     }
 }

source/EasyWay/QueryResult.cs

@@ -5,34 +5,54 @@ namespace EasyWay
     public sealed class QueryResult<TReadModel>
         where TReadModel : ReadModel
     {
-        internal TReadModel ReadModel { get;  }
+        internal TReadModel? ReadModel { get;  }
 
         internal QueryErrorEnum Error { get; }
 
         internal IDictionary<string, string[]> ValidationErrors;
 
+        internal Exception? Exception { get; }
+
         private QueryResult(TReadModel readModel)
         {
             ReadModel = readModel;
+            ValidationErrors = new Dictionary<string, string[]>();
             Error = QueryErrorEnum.None;
+            Exception = null;
         }
 
         private QueryResult(QueryErrorEnum queryError)
         {
             ReadModel = null;
+            ValidationErrors = new Dictionary<string, string[]>();
             Error = queryError;
+            Exception = null;
         }
 
         private QueryResult(IDictionary<string, string[]> validationErrors)
         {
+            ReadModel = null;
             ValidationErrors = validationErrors;
             Error = QueryErrorEnum.Validation;
+            Exception = null;
         }
 
-        public static QueryResult<TReadModel> Ok(TReadModel readModel) => new QueryResult<TReadModel>(readModel);
+        private QueryResult(Exception exception)
+        {
+            ReadModel = null;
+            ValidationErrors = new Dictionary<string, string[]>();
+            Error = QueryErrorEnum.UnknownException;
+            Exception = exception;
+        }
 
         internal static QueryResult<TReadModel> Validation(IDictionary<string, string[]> validationErrors) => new QueryResult<TReadModel>(validationErrors);
 
+        internal static QueryResult<TReadModel> OperationCanceled() => new QueryResult<TReadModel>(QueryErrorEnum.OperationCanceled);
+
+        internal static QueryResult<TReadModel> UnknownException(Exception exception) => new QueryResult<TReadModel>(exception);
+
+        public static QueryResult<TReadModel> Ok(TReadModel readModel) => new QueryResult<TReadModel>(readModel);
+
         public static QueryResult<TReadModel> NotFound => new QueryResult<TReadModel>(QueryErrorEnum.NotFound);
 
         public static QueryResult<TReadModel> Forbidden => new QueryResult<TReadModel>(QueryErrorEnum.Forbidden);