VPSDemo

The goal of the test task is to develop a web API of a task planning system. The web API must allow to create and edit a task hierarchy, as well as perform calculations on the data fields of the tasks in the hierarchy.

Technologies used:

ASP.NET Core 6, C#, EntityFramework Core, MS SQL Server Database, Docker

App architecture used with different layers

• VPSDemo.Api (main Web API project) contains Controllers (endpoints), Contracts, Mappers, Filters.
• VPSDemo.Application contains Interfaces, Errors, Logic to fetch data
• VPSDemo.Domain contains Entities
• VPSDemo.Infrastructure contains Repositories, Migration files and other fiels related to DB

Libraries and patterns:

Clean Architectue, Domain Driven Design, Repository Pattern

AutoMapper

• Automapper is set in VPSDemo.Api.Mapper
• TaskMapperProfiles.cs to configure automapper for Task entity

FluentResults

• Instead of throwing and using exceptions we use a Return object.
• Return object has a Value, IsFailed, IsSuccess properties.
• errors of Return object are handled via ProblemHandler in BaseController.

Error and Validations Handling

• Globar errors are handled in VPSDemo.Api.Controllers ErrorsController.cs
• All other non server side errors are handled via ProblemHandler method in VPSDemo.Api.Controllers BaseController.cs
• Uri and query identifier parameter is validated via ValidateIdentifier method in VPSDemo.Api.Validations BaseValidation.cs
• UI Models (Contracts)are validated via validation filter defined in VPSDemo.Api.Filters ValidationFilterAttribute.cs
• All errors are serverd to the user with ProblemDetails class Problem Details Specification for HTTP APIs
• in order to add custom 'errorMessage' to ProblemDetails class we override method CreateProblemDetails in VPSDemo.Api.Common VPSProblemDetailsFactory.cs

DB and UI models

• DB Model (Entity) defined in VPSDemo.Domain.Entities Task.cs class
• UI models (Contracts) defined in VPSDemo.Api.Contracts

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Capabilities of the Web API

1. Create Task, Delete Task, Edit Task, Get Task, Assign Sub task
2. Get Task - also retrieves sub Tasks
3. Delete Task - Only a task which does not have sub-tasks can be deleted.

Web API Endpoints & Examples

Create

POST VPSDemo_URL/tasks

Request body	Response (SUCCESS 200 Ok)
{ "title": "MAIN TASK A", "description": "description", "effortEstimation": 1 }	{ "identifier": 1, "title": "MAIN TASK A", "description": "description", "effortEstimation": 1, "aggregatedEffortEstimation": 281, "status": "New", "subTasks": [], "creationDate": "2022-11-13T23:15:12" }

Request body	Response (FAIL 400)
{ "description": "description" }	{ "type": "https://tools.ietf.org/html/rfc7231#section-6.5.1", "title": "Validation Error", "status": 400, "traceId": "00-21790aa1386552307b4397420650fefa-18df5db6c8db92e1-00", "errorMessage": [ "The Title field is required." ] }

Edit

PUT VPSDemo_URL/tasks/2

Request body	Response (FAIL 400)
{ "description": "description" }	{ "type": "https://tools.ietf.org/html/rfc7231#section-6.5.1", "title": "Validation Error", "status": 400, "traceId": "00-21790aa1386552307b4397420650fefa-18df5db6c8db92e1-00", "errorMessage": [ "The Status field is required.", "The field Status is invalid" ] }

Assign sub task

PUT VPSDemo_URL/tasks/assignSubTask/4?parentIdentifier=3

Query (Key: Value)	Response (Success 200 Ok)
parentIdentifier: 3	{ "identifier": 3, "title": "TASK B", "description": "description", "effortEstimation": 0, "aggregatedEffortEstimation": 80, "status": "New", "subTasks": [ { "identifier": 4, "title": "TASK C", "description": "description", "effortEstimation": 80, "aggregatedEffortEstimation": 0, "status": "New", "subTasks": [], "creationDate": "2022-11-13T23:17:44" } ], "creationDate": "2022-11-13T23:15:12" }

Fetch

Get VPSDemo_URL/tasks/3

Response (Success 200 Ok)
{ "identifier": 3, "title": "TASK B", "description": "description", "effortEstimation": 0, "aggregatedEffortEstimation": 80, "status": "New", "subTasks": [ { "identifier": 4, "title": "TASK C", "description": "description", "effortEstimation": 80, "aggregatedEffortEstimation": 0, "status": "New", "subTasks": [], "creationDate": "2022-11-13T23:17:44" } ], "creationDate": "2022-11-13T23:15:12" }

Delete

Delete VPSDemo_URL/tasks/3

Response (Success 204 NoContent)

Delete VPSDemo_URL/tasks/1

Response (FAIL 409)
{ "type": "https://tools.ietf.org/html/rfc7231#section-6.5.8", "title": "Conflict", "status": 409, "traceId": "00-7d2127bfe809238b8d944c0cb64fec29-d17390d3fe719a93-00", "errorMessage": [ "Task with identifier [1] has assigned one or more Task with identifiers: [4]" ] }

Docker

VPSDemo.Api contains Dockerfile to build docker image.
We use base image mcr.microsoft.com/dotnet/sdk:6.0 to build binaries.
.Net runtime image mcr.microsoft.com/dotnet/aspnet:6.0 is used to serve artefacts we've created

Local docker container running our image:

Opening the browser to display app runnig from docker container: