README.md

Back-end Development Process

Spring Boot Setup

• Spring Data JPA
• REST Repository
• MySQL Driver
• Lombok

Database Setup - Hibernate/JPA

1. Create database for Entities [create-database.sql] [countries-and-states.sql]
2. Configure JDBC connection and Hibernate dialect in application.properties
3. Create JPA Entity classes [Product] [ProductCategory] [Country] [State]

Spring Data JPA/REST

1. Create Repositories [ProductRepository] [ProductCategoryRepository] [CountryRepository] [StateRepository]
   • Use @RepositoryRestResource to customize JSON entry and API endpoint
   • Create custom query methods by Query Methods
2. Customize base path for REST API in application.properties
3. Create Spring Data REST Configuration with @Configuration implements RepositoryRestConfigurer for custom configuration [DataRestConfig]
   • Disable certain HTTP methods for certain Entities
   • Expose Entity id fields for the API
     • Inject JPA entity manager (recommend by the constructor): to retrieve list of all Entity types
     • Alternative method: declare field by uppercase Id instead of id. However, this is not a documented feature -> not recommend

Notes

• [Hibernate] @CreationTimestamp & @UpdateTimestamp [Product]
• [SpringDataJPA&Lombok]Using @Data on both Entity classes in the OneToMany relationship may cause bug -> Use @Data for one side, @Getter and @Setter for the other.
• [SpringDataJPA] Add @CrossOrigin to Repositories to accept calls from web browser script for the origin (Angular app)
• [SpringDataJPA] Use @Query to define a custom query method in the JPA Repository
• [SpringDataJPA] JPA Repository method starts with findBy... will be exposed by Data REST as endpoint /search/findBy... [ProductRepository]
• [SpringDataREST] Spring Data REST API supports pagination
  • Returns 20 entries per page by default
  • Endpoint: <entities>?page=<number>&size=<number s- When working with Spring Data REST we should actually use @Param instead of @RequestParam.