Customer Relationships Management Rest API (Spring Boot)

Endpoints

Service layer

• GET /api/customers
• GET /api/customers/{id}
• POST /api/customers
• PUT /api/customers
• DELETE /api/customers/{id}

Non-service layer

Same as Service layer but replace api by api2

Spring Data REST

• GET /magic-api/customers
• GET /magic-api/customers?page={number}: pages are zero-based
• GET /magic-api/customers?sort=lastName
• GET /magic-api/customers?sort=firstName,desc
• GET /magic-api/customers/{id}
• POST /magic-api/customers
• PUT /magic-api/customers/{id}
• DELTE /magic-api/customers/{id}

Configuration

1. Spring Boot configurations with following dependencies: [Reference]
   • Spring Web
   • MySQL Driver
   • Spring Data JPA
   • Rest Repositories (Spring Data Rest)
   • Spring Boot DevTools (Optional)
   • Lombok (Optional)
2. Setup database
3. Configure application.properties for database [application.properties]

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Spring Data JPA

1. Create Entity classes [Customer]
2. Create Repository interfaces extend JpaRepository [CutomerRepository]

Service Layer

3. Create Service interfaces [CustomerService]
4. Create Service implementation classes [CustomerServiceImpl]
   • Inject the Repository by constructor
   • Implementing interface methods by delegating to Reposity methods (auto defined by Spring Data JPA)
   • No need @Transactional for implement method since inject the Repository
5. Create Rest Controller [CustomerRestController]
   • Inject the Service by constructor
   • Define endpoints

Non-Service Layer

3. Create Rest Controller [CustomerNoServiceRestController]
   • Inject the Repository by constructor
   • Define endpoints

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Spring Data REST

• Rest Controllers are not required
• Service layer is not required
• Apply HATEOSA format for auto-defined endpoints
• Endpoints, pagination can be configured in application.properties
• Simple pluralized form
  • First charater of Entity type is lowercase
  • Then just add an "s"
  • For example: Customer -> <port>/customers
• Specify plural name/path with @RepositoryRestResource(path="<name>") in the Repository [CustomerRepository]
• Only use ID in the URL (not Response body) for PUT

Notes/Tips

• Recommend inject by constructors instead of fields (for testing purposes)