Spring Boot Task Management REST API

Project roadmap

1. 01

   Create the project

   ~1h

   Create a Spring Boot project (with Spring Initializr) with Web, Data JPA, Validation, PostgreSQL and Flyway. Run PostgreSQL with Docker Compose and configure the connection. Add a GET /health endpoint (or Actuator). Done when: the app starts and connects to the database.

2. 02

   Define the entities

   ~1.5h

   Create the tables with a Flyway migration, and JPA entities Project (name unique, description and created at) and Task (title, description, status TODO, IN_PROGRESS or DONE, priority, due date and its project), with a @OneToMany and @ManyToOne relationship, lazy loading, and deleting a project's tasks when it's deleted. Done when: projects with tasks can be saved and loaded in a quick test.

3. 03

   Build the layers

   ~2.5h

   Create repositories (JpaRepository), services with the rules (a task's due date can't be in the past when created, and a DONE task can't go back to TODO), and controllers for projects (CRUD) and their tasks (CRUD under /projects/{id}/tasks, plus changing a task's status). Use request and response DTOs (Java records) instead of exposing entities. Done when: every endpoint works with curl.

4. 04

   Validate and handle errors

   ~1.5h

   Add Bean Validation annotations to the request DTOs (@NotBlank, @Size and @FutureOrPresent) with @Valid in controllers, and a @RestControllerAdvice that turns validation errors into 400 with field messages, missing items into 404, rule violations into 409, and unexpected errors into 500, all as ProblemDetail responses. Done when: every error comes back in the same clear format.

5. 05

   Add filtering and pagination

   ~1.5h

   Support GET /projects/{id}/tasks?status=&priority=&dueBefore=&page=&size=&sort= using Spring Data's Pageable and a Specification (or derived queries) for the optional filters, returning items with paging information. Make the project list show each project's task counts without loading every task (with a query or @EntityGraph), and check the number of SQL queries in the log. Done when: filters and paging work, and listing runs a small, fixed number of queries.

6. 06

   Write integration tests

   ~2h

   Write @SpringBootTest integration tests with MockMvc (or TestRestTemplate) against a real PostgreSQL with Testcontainers: CRUD for projects and tasks, the status rules, validation errors, 404s, filtering, paging and sorting, and deleting a project with its tasks. Done when: all tests pass.

Resources

• DocsSpring guide: building a RESTful web service
• DocsSpring guide: accessing data with JPA
• DocsSpring Data JPA: specifications
• DocsSpring guide: validating form input
• DocsTestcontainers for Java