Tested for ABP v0.3.2. Also commented codes.

Author: hikalkan

SimpleTaskSystem/SimpleTaskSystem.Application/DtoMappings/DtoMapping.cs renamed to SimpleTaskSystem/SimpleTaskSystem.Application/DtoMappings.cs

@@ -4,12 +4,14 @@
 using SimpleTaskSystem.Tasks;
 using SimpleTaskSystem.Tasks.Dtos;
 
-namespace SimpleTaskSystem.DtoMappings
+namespace SimpleTaskSystem
 {
-    internal static class DtoMapping
+    internal static class DtoMappings
     {
         public static void Map()
         {
+            //This code configures AutoMapper to auto map between Entities and DTOs.
+
             Mapper.CreateMap<Task, TaskDto>();
             Mapper.CreateMap<Person, PersonDto>();
         }

SimpleTaskSystem/SimpleTaskSystem.Application/README.md

@@ -0,0 +1,4 @@
+Simple task system - Application (service) layer.
+-----------------------------------------
+
+This layer contains application services and DTOs. Application layer is used by presentation layer and uses domain (core) layer to perform application specific operations.

SimpleTaskSystem/SimpleTaskSystem.Application/SimpleTaskSystem.Application.csproj

@@ -30,13 +30,13 @@
     <WarningLevel>4</WarningLevel>
   </PropertyGroup>
   <ItemGroup>
-    <Reference Include="Abp, Version=0.3.1.2, Culture=neutral, processorArchitecture=MSIL">
+    <Reference Include="Abp, Version=0.3.1.3, Culture=neutral, processorArchitecture=MSIL">
       <SpecificVersion>False</SpecificVersion>
-      <HintPath>..\packages\Abp.0.3.1.2\lib\net451\Abp.dll</HintPath>
+      <HintPath>..\packages\Abp.0.3.1.3\lib\net451\Abp.dll</HintPath>
     </Reference>
-    <Reference Include="Abp.Application, Version=0.3.1.2, Culture=neutral, processorArchitecture=MSIL">
+    <Reference Include="Abp.Application, Version=0.3.1.3, Culture=neutral, processorArchitecture=MSIL">
       <SpecificVersion>False</SpecificVersion>
-      <HintPath>..\packages\Abp.Application.0.3.1.2\lib\net451\Abp.Application.dll</HintPath>
+      <HintPath>..\packages\Abp.Application.0.3.1.3\lib\net451\Abp.Application.dll</HintPath>
     </Reference>
     <Reference Include="AutoMapper, Version=3.2.1.0, Culture=neutral, PublicKeyToken=be96cd2c38ef1005, processorArchitecture=MSIL">
       <SpecificVersion>False</SpecificVersion>
@@ -78,7 +78,7 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
-    <Compile Include="DtoMappings\DtoMapping.cs" />
+    <Compile Include="DtoMappings.cs" />
     <Compile Include="People\Dtos\GetAllPeopleOutput.cs" />
     <Compile Include="People\Dtos\PersonDto.cs" />
     <Compile Include="People\IPersonAppService.cs" />
@@ -96,6 +96,7 @@
   <ItemGroup>
     <None Include="app.config" />
     <None Include="packages.config" />
+    <None Include="README.md" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\SimpleTaskSystem.Core\SimpleTaskSystem.Core.csproj">

SimpleTaskSystem/SimpleTaskSystem.Application/SimpleTaskSystemApplicationModule.cs

@@ -3,12 +3,17 @@
 using Abp.Dependency;
 using Abp.Modules;
 using Abp.Startup;
-using SimpleTaskSystem.DtoMappings;
 
 namespace SimpleTaskSystem
 {
+    /// <summary>
+    /// 'Aplication layer module' for this project.
+    /// </summary>
     public class SimpleTaskSystemApplicationModule : AbpModule
     {
+        /// <summary>
+        /// We declare depended modules explicitly.
+        /// </summary>
         public override Type[] GetDependedModules()
         {
             return new[]
@@ -20,8 +25,12 @@ public override Type[] GetDependedModules()
         public override void Initialize(IAbpInitializationContext initializationContext)
         {
             base.Initialize(initializationContext);
+
+            //This code is used to register classes to dependency injection system for this assembly using conventions.
             IocManager.Instance.RegisterAssemblyByConvention(Assembly.GetExecutingAssembly());
-            DtoMapping.Map();
+
+            //We must declare mappings to be able to use AutoMapper
+            DtoMappings.Map();
         }
     }
 }

SimpleTaskSystem/SimpleTaskSystem.Application/Tasks/Dtos/TaskDto.cs

@@ -3,6 +3,9 @@
 
 namespace SimpleTaskSystem.Tasks.Dtos
 {
+    /// <summary>
+    /// A DTO class that can be used in various application service methods when needed to send/receive Task objects.
+    /// </summary>
     public class TaskDto : EntityDto<long>
     {
         public int AssignedPersonId { get; set; }

SimpleTaskSystem/SimpleTaskSystem.Application/Tasks/Dtos/UpdateTaskInput.cs

@@ -5,15 +5,22 @@
 
 namespace SimpleTaskSystem.Tasks.Dtos
 {
+    /// <summary>
+    /// This DTO class is used to send needed data to <see cref="ITaskAppService.UpdateTask"/> method.
+    /// 
+    /// Implements <see cref="IInputDto"/>, thus ABP applies standard input process (like automatic validation) for it. 
+    /// Implements <see cref="ICustomValidate"/> for additional custom validation.
+    /// </summary>
     public class UpdateTaskInput : IInputDto, ICustomValidate
     {
-        [Range(1, long.MaxValue)]
+        [Range(1, long.MaxValue)] //Data annotation attributes work as expected.
         public long TaskId { get; set; }
 
         public int? AssignedPersonId { get; set; }
 
         public TaskState? State { get; set; }
 
+        //Custom validation method. It's valled by ABP after data annotation validations.
         public void AddValidationErrors(List<ValidationResult> results)
         {
             if (AssignedPersonId == null && State == null)

SimpleTaskSystem/SimpleTaskSystem.Application/Tasks/ITaskAppService.cs

@@ -3,10 +3,21 @@
 
 namespace SimpleTaskSystem.Tasks
 {
+    /// <summary>
+    /// Defines an application service for <see cref="Task"/> operations.
+    /// 
+    /// It extends <see cref="IApplicationService"/>.
+    /// Thus, ABP enables automatic dependency injection, validation and other benefits for it.
+    /// 
+    /// Application services works with DTOs (Data Transfer Objects).
+    /// Service methods gets and returns DTOs.
+    /// </summary>
     public interface ITaskAppService : IApplicationService
     {
         GetTasksOutput GetTasks(GetTasksInput input);
+
         void UpdateTask(UpdateTaskInput input);
+        
         void CreateTask(CreateTaskInput input);
     }
 }

SimpleTaskSystem/SimpleTaskSystem.Application/Tasks/TaskAppService.cs

@@ -6,32 +6,51 @@
 
 namespace SimpleTaskSystem.Tasks
 {
+    /// <summary>
+    /// Implements <see cref="ITaskAppService"/> to perform task related application functionality.
+    /// 
+    /// Inherits from <see cref="ApplicationService"/>.
+    /// <see cref="ApplicationService"/> contains some basic functionality common for application services (such as logging and localization).
+    /// </summary>
     public class TaskAppService : ApplicationService, ITaskAppService
     {
+        // These members set in constructor using constructor injection.
+        
         private readonly ITaskRepository _taskRepository;
         private readonly IPersonRepository _personRepository;
-
+        
+        /// <summary>
+        ///In constructor, we can get needed classes/interfaces.
+        ///They are sent here by dependency injection system automatically.
+        /// </summary>
         public TaskAppService(ITaskRepository taskRepository, IPersonRepository personRepository)
         {
             _taskRepository = taskRepository;
             _personRepository = personRepository;
         }
-
+        
         public GetTasksOutput GetTasks(GetTasksInput input)
         {
+            //Called specific GetAllWithPeople of task repository.
             var tasks = _taskRepository.GetAllWithPeople(input.AssignedPersonId, input.State);
+
+            //Used AutoMapper to automatically convert List<Task> to List<TaskDto>.
             return new GetTasksOutput
                    {
                        Tasks = Mapper.Map<List<TaskDto>>(tasks)
                    };
         }
-
+        
         public void UpdateTask(UpdateTaskInput input)
         {
+            //We can use Logger, it's defined in ApplicationService class.
             Logger.Info("Updating a task for input: " + input);
 
+            //Retrieving a task entity with given id using standard Get method of repositories.
             var task = _taskRepository.Get(input.TaskId);
 
+            //Updating changed peoperties of the retrieved task entity.
+
             if (input.State.HasValue)
             {
                 task.State = input.State.Value;
@@ -41,19 +60,26 @@ public void UpdateTask(UpdateTaskInput input)
             {
                 task.AssignedPerson = _personRepository.Load(input.AssignedPersonId.Value);
             }
+
+            //We even do not call Update method of the repository.
+            //Because an application service method is a 'unit of work' scope as default.
+            //ABP automatically saves all changes when a 'unit of work' scope ends (without any exception).
         }
 
         public void CreateTask(CreateTaskInput input)
         {
+            //We can use Logger, it's defined in ApplicationService class.
             Logger.Info("Creating a new task with description: " + input.Description);
 
+            //Creating a new Task entity with given input's properties
             var task = new Task { Description = input.Description };
 
             if (input.AssignedPersonId.HasValue)
             {
                 task.AssignedPersonId = input.AssignedPersonId.Value;
             }
 
+            //Saving entity with standard Insert method of repositories.
             _taskRepository.Insert(task);
         }
     }

SimpleTaskSystem/SimpleTaskSystem.Application/packages.config

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="Abp" version="0.3.1.2" targetFramework="net451" />
-  <package id="Abp.Application" version="0.3.1.2" targetFramework="net451" />
+  <package id="Abp" version="0.3.1.3" targetFramework="net451" />
+  <package id="Abp.Application" version="0.3.1.3" targetFramework="net451" />
   <package id="AutoMapper" version="3.2.1" targetFramework="net451" />
   <package id="Castle.Core" version="3.3.0" targetFramework="net451" />
   <package id="Castle.Core-log4net" version="3.3.0" targetFramework="net451" />

SimpleTaskSystem/SimpleTaskSystem.Core/People/IPersonRepository.cs

@@ -2,8 +2,13 @@
 
 namespace SimpleTaskSystem.People
 {
+    /// <summary>
+    /// Defines a repository to perform database operations for <see cref="Person"/> Entities.
+    /// 
+    /// Extends <see cref="IRepository{TEntity}"/> to inherit base repository functionality.
+    /// </summary>
     public interface IPersonRepository : IRepository<Person>
     {
-
+        //We can add methods here those are specific to Person entities. Currently, we don't need it, base methods enough.
     }
 }