Spring Cloud config中，使用数据库存储配置信息

主要内容

在springcloud config中，使用数据库存储配置信息。

系统默认采用git的方式，此处我们介绍使用jdbc的方式存储配置信息

准备数据库

数据库我们使用mysql。
新建库 p-config-server

创建配置需要的表，并初始化一些配置信息

CREATE TABLE `properties` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `application` varchar(64) COLLATE utf8_bin NOT NULL DEFAULT '',
  `profile` varchar(64) COLLATE utf8_bin NOT NULL DEFAULT '',
  `label` varchar(64) COLLATE utf8_bin NOT NULL DEFAULT '',
  `key` varchar(128) COLLATE utf8_bin NOT NULL DEFAULT '',
  `value` varchar(4096) COLLATE utf8_bin NOT NULL DEFAULT '',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=9 DEFAULT CHARSET=utf8 COLLATE=utf8_bin;

INSERT INTO `properties` VALUES ('1', 'p-config-client', 'dev', 'master', 'key-1', 'value-1');
INSERT INTO `properties` VALUES ('2', 'p-config-client', 'dev', 'master', 'key-2', 'value-2');
INSERT INTO `properties` VALUES ('3', 'p-config-client', 'dev1', 'master', 'key-1', 'value-3');
INSERT INTO `properties` VALUES ('4', 'p-config-client', 'dev1', 'master', 'key-4', 'value-4');
INSERT INTO `properties` VALUES ('5', 'p-config-client', 'dev1', 'master', 'key-5', 'value-5');

创建eureka注册中心

创建springcloud项目p-eureka
```
groupId: com.ms
artifactId: p-eureka
```

pom.xml内容

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>2.1.4.RELEASE</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>com.ms</groupId>
	<artifactId>p-eureka</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>p-eureka</name>
	<description>Demo project for Spring Boot</description>

	<properties>
		<java.version>1.8</java.version>
		<spring-cloud.version>Greenwich.SR1</spring-cloud.version>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.springframework.cloud</groupId>
			<artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
	</dependencies>

	<dependencyManagement>
		<dependencies>
			<dependency>
				<groupId>org.springframework.cloud</groupId>
				<artifactId>spring-cloud-dependencies</artifactId>
				<version>${spring-cloud.version}</version>
				<type>pom</type>
				<scope>import</scope>
			</dependency>
		</dependencies>
	</dependencyManagement>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
		</plugins>
	</build>

</project>

application.properties改为application.yml

server:
  port: 7001
spring:
  application:
    name: p-eureka
eureka:
  client:
    register-with-eureka: false
    fetch-registry: false
    service-url:
      defaultZone: http://localhost:7001/eureka/

PEurekaApplication内容

package com.ms;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;

@SpringBootApplication
@EnableEurekaServer
public class PEurekaApplication {

	public static void main(String[] args) {
		SpringApplication.run(PEurekaApplication.class, args);
	}

}

注意：

@EnableEurekaServer：表示这是一个eureka注册中心

运行PEurekaApplication
访问http://localhost:7001/

创建配置中心(config server)

创建springcloud项目p-config-server

groupId: com.ms
artifactId: p-config-server

pom.xml内容

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.4.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.ms</groupId>
    <artifactId>p-config-server</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>p-config-server</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Finchley.SR1</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-config-server</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

application.yml 内容

server:
  port: 8080
eureka:
  client:
    service-url:
      defaultZone: http://localhost:7001/eureka/
spring:
  application:
    name: p-config-server
  cloud:
    config:
      enabled: true
      profile: jdbc
      server:
        jdbc:
          sql: SELECT `key`, `value` from PROPERTIES where application=? and profile=? and label=?
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://localhost:3306/config-server?characterEncoding=UTF-8
    username: root
    password: root123
    type: com.zaxxer.hikari.HikariDataSource
  profiles:
    active: jdbc

注意：

数据连接地址、用户名、密码，这些值根据自己的机器进行修改

PConfigServerApplication内容

package com.ms;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.config.server.EnableConfigServer;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;

@SpringBootApplication
@EnableConfigServer
@EnableEurekaClient
public class PConfigServerApplication {

    public static void main(String[] args) {
        SpringApplication.run(PConfigServerApplication.class, args);
    }

}

注意：

@EnableConfigServer：表示这是一个注册中心应用
@EnableEurekaClient：将当前服务注册到eureka中，可以被其他应用发现，然后使用

运行PConfigServerApplication
访问：http://localhost:8080/master/p-config-client-dev,dev1.yml 结果如下：
```
key-1: value-3
key-2: value-2
key-4: value-4
key-5: value-5
```

创建客户端

创建springcloud项目p-config-client

groupId: com.ms
artifactId: p-config-client

pom.xml内容

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.4.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.ms</groupId>
    <artifactId>p-config-client</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>p-config-client</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Finchley.SR1</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-config</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

application.properties改为bootstrap.yml 内容

注意：此处必须使用bootstrap名称
```
server:
  port: 8081
spring:
  application:
    name: p-config-client
  cloud:
    config:
      discovery:
        enabled: true
        service-id: p-config-server
      name: ${spring.application.name}
      profile: dev,dev1
      label: master
      override-system-properties: false
eureka:
  client:
    service-url:
      defaultZone: http://localhost:7001/eureka/
```
- config.name对应数据库properties表中的application字段
- config.profile对应表中的profile字段，config.profile如果包含多个值，之间用英文逗号隔开
- config.label对应表中的label字段，我们可以使用label来区分环境(dev【开发环境】、test【测试环境】、prod【线上环境】)

PConfigClientApplication内容

package com.ms;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;

@SpringBootApplication
@EnableEurekaClient
public class PConfigClientApplication {

	public static void main(String[] args) {
		SpringApplication.run(PConfigClientApplication.class, args);
	}

}

注意：

@EnableEurekaClient：当前应用会访问eureka注册中心，发现config service

创建DemoController

package com.ms;

import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.core.env.Environment;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.HashMap;
import java.util.Map;

@RestController
@Slf4j
public class DemoController {

    @Autowired
    private Environment environment;

    @RequestMapping("/{key}")
    public String index(@PathVariable("key") String key) {
        return this.environment.getProperty(key);
    }
}

运行PConfigClientApplication
访问 http://localhost:8081/key-1 结果如下：
```
value-3
```

总结

使用数据库存储配置信息还是比较靠谱的，相对于git来说会更好一些
代码已上传至git，获取源码方式：微信公众号javacode2018，发送：sccj

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原文地址：https://www.cnblogs.com/itsoku123/p/10871007.html