只读副本和Spring Data第2部分：配置基础项目

在上一篇文章中，我们使用相同的数据设置了多个PostgreSQL实例。
我们的下一步将是使用这两个服务器来配置我们的spring项目。

如前所述，由于我们使用完全相同的数据库，因此我们将使用Spring Boot JPA帖子中的一些代码。

这将是我们的gradle构建文件

 plugins { id 'org.springframework.boot' version '2.1.9.RELEASE' id 'io.spring.dependency-management' version '1.0.8.RELEASE' id 'java'  }  group = 'com.gkatzioura'  version = '0.0.1-SNAPSHOT'  sourceCompatibility = '1.8'  repositories { mavenCentral()  }  dependencies { implementation 'org.springframework.boot:spring-boot-starter-data-jpa' implementation 'org.springframework.boot:spring-boot-starter-web' implementation "org.postgresql:postgresql:42.2.8" testImplementation 'org.springframework.boot:spring-boot-starter-test'  }

现在，让我们基于上一个博客上创建的表来创建模型。

 package com.gkatzioura.springdatareadreplica.entity;  import javax.persistence.Column;  import javax.persistence.Entity;  import javax.persistence.GeneratedValue;  import javax.persistence.GenerationType;  import javax.persistence.Id;  import javax.persistence.Table;  @Entity  @Table (name = "employee" , catalog= "spring_data_jpa_example" )  public class Employee { @Id @Column (name = "id" ) @GeneratedValue (strategy = GenerationType.IDENTITY) private Long id; @Column (name = "firstname" ) private String firstName; @Column (name = "lastname" ) private String lastname; @Column (name = "email" ) private String email; @Column (name = "age" ) private Integer age; @Column (name = "salary" ) private Integer salary; public Long getId() { return id; } public void setId(Long id) { this .id = id; } public String getFirstName() { return firstName; } public void setFirstName(String firstName) { this .firstName = firstName; } public String getLastname() { return lastname; } public void setLastname(String lastname) { this .lastname = lastname; } public String getEmail() { return email; } public void setEmail(String email) { this .email = email; } public Integer getAge() { return age; } public void setAge(Integer age) { this .age = age; } public Integer getSalary() { return salary; } public void setSalary(Integer salary) { this .salary = salary; }  }

下一步是创建spring数据存储库。

 package com.gkatzioura.springdatareadreplica.repository;  import org.springframework.data.jpa.repository.JpaRepository;  import com.gkatzioura.springdatareadreplica.entity.Employee;  public interface EmployeeRepository extends JpaRepository<Employee,Long> {  }

另外，我们将添加一个控制器。

 package com.gkatzioura.springdatareadreplica.controller;  import java.util.List;  import org.springframework.web.bind.annotation.RequestMapping;  import org.springframework.web.bind.annotation.RestController;  import com.gkatzioura.springdatareadreplica.entity.Employee;  import com.gkatzioura.springdatareadreplica.repository.EmployeeRepository;  @RestController  public class EmployeeContoller { private final EmployeeRepository employeeRepository; public EmployeeContoller(EmployeeRepository employeeRepository) { this .employeeRepository = employeeRepository; } @RequestMapping ( "/employee" ) public List<Employee> getEmployees() { return employeeRepository.findAll(); }  }

它所要做的只是在application.yaml中添加正确的属性。

 spring: datasource: platform: postgres driverClassName: org.postgresql.Driver username: db-user password: your-password url: jdbc:postgresql: //127.0.0.2:5432/postgres url: jdbc:postgresql: //127.0.0.2:5432/postgres url: jdbc:postgresql:

如今，Spring Boot使得不必理会任何JPA配置。

这是运行该应用程序所需的全部。一旦您的应用程序运行，只需尝试获取员工。