Java之SpringCloud nocos註冊中心講解
一、nacos是什麼？
Nacos是用來發現、配置和管理微服務。Nacos提供瞭一組簡單易用的特性集，幫助快速實現動態服務發現、服務配置、服務元數據及流量管理。
二、使用步驟
1.安裝nacos 服務器
直接運行 startup.cmd 訪問 localhost:8848/nacos
初始密碼 nacos nacos
2.導入依賴和配置yaml
父項目依賴pom文件
<?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>
<groupId>com.csdn</groupId>
<artifactId>springcloud_nacos</artifactId>
<packaging>pom</packaging>
<version>1.0-SNAPSHOT</version>
<modules>
<module>springcloud_share_6002</module>
<module>springcloud_user_6001</module>
<module>springcloud_common</module>
</modules>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
<junit.version>4.12</junit.version>
<lombok.version>1.18.16</lombok.version>
<log4j.version>1.2.17</log4j.version>
<logback-core.version>1.2.3</logback-core.version>
<mysql-connector-java.version>8.0.21</mysql-connector-java.version>
<druid.version>1.1.23</druid.version>
<mybatis-spring-boot-starter.version>2.1.4</mybatis-spring-boot-starter.version>
<spring-boot-dependencies.version>2.3.8.RELEASE</spring-boot-dependencies.version>
<spring-cloud-dependencies.version>Hoxton.SR9</spring-cloud-dependencies.version>
<spring-cloud-alibaba.version>2.2.3.RELEASE</spring-cloud-alibaba.version>
<swagger.version>2.7.0</swagger.version>
<pagehelper.version>1.2.3</pagehelper.version>
<jodatime.version>2.10.1</jodatime.version>
<jjwt.version>0.10.7</jjwt.version>
</properties>
<dependencyManagement>
<dependencies>
<!--很重要的包：springcloud的依賴-->
<!-- <scope>import</scope>解決單繼承問題，類似parent標簽， -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud-dependencies.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
<!--spring-cloud-alibaba-->
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-alibaba-dependencies</artifactId>
<version>${spring-cloud-alibaba.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
<!--springboot-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-dependencies</artifactId>
<version>${spring-boot-dependencies.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
<!--數據庫-->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>${mysql-connector-java.version}</version>
</dependency>
<!--數據源-->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>${druid.version}</version>
</dependency>
<!--mybatis的springboot啟動器-->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>${mybatis-spring-boot-starter.version}</version>
</dependency>
<!--日志測試-->
<!--junit-->
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>${junit.version}</version>
</dependency>
<!--lombok-->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>${lombok.version}</version>
</dependency>
<!--log4j-->
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>${log4j.version}</version>
</dependency>
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-core</artifactId>
<version>${logback-core.version}</version>
</dependency>
<!--swagger-->
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger2</artifactId>
<version>${swagger.version}</version>
</dependency>
<!--swagger ui-->
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger-ui</artifactId>
<version>${swagger.version}</version>
</dependency>
<!--druid alibaba-->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid-spring-boot-starter</artifactId>
<version>${druid.version}</version>
</dependency>
<dependency>
<groupId>com.github.pagehelper</groupId>
<artifactId>pagehelper-spring-boot-starter</artifactId>
<version>${pagehelper.version}</version>
</dependency>
<!--日期時間工具-->
<dependency>
<groupId>joda-time</groupId>
<artifactId>joda-time</artifactId>
<version>${jodatime.version}</version>
</dependency>
<!-- JWT -->
<dependency>
<groupId>io.jsonwebtoken</groupId>
<artifactId>jjwt-api</artifactId>
<version>${jjwt.version}</version>
</dependency>
<dependency>
<groupId>io.jsonwebtoken</groupId>
<artifactId>jjwt-impl</artifactId>
<version>${jjwt.version}</version>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>io.jsonwebtoken</groupId>
<artifactId>jjwt-jackson</artifactId>
<version>${jjwt.version}</version>
<scope>runtime</scope>
</dependency>
</dependencies>
</dependencyManagement>
<build>
<!--打包插件-->
</build>
</project>
在需要被nacos發現的微服務個module加上nacos依賴
<!--服務註冊-->
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
</dependency>
springcloud_common的pom依賴
<?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">
<parent>
<artifactId>springcloud_nacos</artifactId>
<groupId>com.csdn</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>springcloud_common</artifactId>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</dependency>
<!--swagger-->
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger2</artifactId>
</dependency>
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger-ui</artifactId>
</dependency>
<!--spring默認使用yml中的配置，但有時候要用傳統的xml或properties配置，就需要使用spring-boot-configuration-processor瞭-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-configuration-processor</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-amqp</artifactId>
</dependency>
<!--服務註冊-->
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
</dependency>
<!--服務容錯-->
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-sentinel</artifactId>
</dependency>
<!--feign-->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>
<!-- JWT -->
<dependency>
<groupId>io.jsonwebtoken</groupId>
<artifactId>jjwt-api</artifactId>
</dependency>
<dependency>
<groupId>io.jsonwebtoken</groupId>
<artifactId>jjwt-impl</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>io.jsonwebtoken</groupId>
<artifactId>jjwt-jackson</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-sleuth</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-zipkin</artifactId>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</dependency>
</dependencies>
</project>
@Configuration
@EnableSwagger2
public class Swagger2Config {
/**
* 定義接口的總體信息
*
* @return
*/
private ApiInfo webApiInfo() {
return new ApiInfoBuilder()
.title("Swagger API 文檔")
.description("即使再小的帆也能遠航")
.version("1.0")
.contact(new Contact("liar", "http://www.jsxllht.com", "**********[email protected]"))
.build();
}
private ApiInfo adminApiInfo() {
return new ApiInfoBuilder()
.title("Swagger Admin 文檔")
.description("即使再小的帆也能遠航")
.version("1.0")
.contact(new Contact("liar", "http://www.jsxllht.com", "**********[email protected]"))
.build();
}
@Bean
public Docket webApiConfig() {
return new Docket(DocumentationType.SWAGGER_2)
.groupName("webApi") // 用戶組
.apiInfo(webApiInfo()) // 組的信息
.select()
//隻顯示api路徑下的頁面
.paths(Predicates.and(PathSelectors.regex("/api/.*"))) // 用戶接口的判斷
.build();
}
@Bean
public Docket adminApiConfig() {
return new Docket(DocumentationType.SWAGGER_2)
.groupName("adminApi") // 管路⚪組
.apiInfo(adminApiInfo()) // 組的信息
.select()
//隻顯示admin路徑下的頁面
.paths(Predicates.and(PathSelectors.regex("/admin/.*")))
.build();
}
}
/**
* 業務異常類
*/
@Data
@NoArgsConstructor
@AllArgsConstructor
@Builder
public class AppException extends RuntimeException{
private String code;
private String message;
public AppException(ResponseEnum responseEnum){
this.code = responseEnum.getCode();
this.message = responseEnum.getMessage();
}
}
// 這是一個controller 的增強類【專門在controller 拋出異常的時候 增強】
@ControllerAdvice
public class ControllerExceptionAdvice {
/**
* 如果拋出的是 AppException 的增強
* 返回值 就是返回的頁面
* 參數： controller 拋出的異常
*/
@ExceptionHandler(AppException.class)
@ResponseBody
public R appExceptionHandler(AppException ex, HttpServletRequest request){
return new R(ex.getCode(),ex.getMessage(),null);
}
/**
* 如果拋出的是Exception 的增強
*/
@ExceptionHandler(Exception.class)
@ResponseBody
public R exceptionHandler(Exception ex, HttpServletRequest request){
ex.printStackTrace();
return new R(ResponseEnum.SYSTEM_ERROR,null);
}
}
@Data
@AllArgsConstructor
@NoArgsConstructor
@Builder
// 創建統一的返回格式
public class R<T> {
private String code;
private String message;
private T data;
public R(ResponseEnum responseEnum, T data) {
this.code = responseEnum.getCode();
this.message = responseEnum.getMessage();
this.data = data;
}
}
public enum ResponseEnum {
SUCCESS("200","成功003"),
USERNAME_NOT_FOUND("300","用戶名不存在"),
USERNAME_OR_PASSWORD_INVALIDATE("301","用戶名或者密碼錯誤"),
ROLE_NO_MENUS("302","此角色沒有任何菜單權限，請盡早分配"),
HAS_NO_TOKEN("303","還沒有登錄"),
TOKEN_ERROR("304","別想試圖偽造令牌"),
TOKEN_TIMEOUT("305","對不起登錄狀態已經失效，請重新登錄"),
HAS_NO_RIGHT("306","權限不足"),
SYSTEM_ERROR("500","發生未知異常。。。"),
FEIGN_BSUY("307","系統正忙，稍後再試。。"),
FLOW_BLOCK("308","流量被限制瞭，請稍後再使"),
DEG_BLOCK("309","系統很忙，稍後再試。。。"),
SMS_ERROR("310","短信發送失敗，請稍後再試。。。"),
SMS_SEND_ERROR_BUSINESS_LIMIT_CONTROL("311","發送短信太頻繁，過會再發。。。"),
CODE_ERROR("312","驗證碼錯誤請重試"),
CODE_EXCPTION("313","驗證碼超時"),
ACCOUNT_NO_EXISTS("314","用戶不存在"),
STATUS_BE_MODIFIED("315","用戶已被審核")
;
private String code;
private String message;
public String getCode() {
return code;
}
public void setCode(String code) {
this.code = code;
}
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
ResponseEnum(String code, String message) {
this.code = code;
this.message = message;
}
}
springcloud_user_6001的yaml（在註冊中心服務的名字 不能一樣）
server:
port: 6001
#數據源
spring:
datasource:
druid:
url: jdbc:mysql://localhost:3306/hub_user_center?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=GMT
driver-class-name: com.mysql.cj.jdbc.Driver
username: root
password: 123456
initial-size: 10
max-active: 50
min-idle: 10
max-wait: 60000
pool-prepared-statements: true
max-pool-prepared-statement-per-connection-size: 20
# mysql 數據庫的特征 會關閉已經連接瞭8個小時的連接
validation-query: SELECT 1 FROM DUAL
application:
name: user-6001
cloud:
nacos:
discovery:
server-addr: 127.0.0.1:8848
# mybatis 配置
mybatis:
# 掃描映射文件
mapper-locations: classpath:mapper/*.xml
configuration:
# 開啟駝峰映射配置
map-underscore-to-camel-case: true
# log
# 整個工程隻答應info 以及以上級別的日志
logging:
level:
root: info
com.csqf.mapper: debug
springcloud_share_6002的yaml（在註冊中心服務的名字 不能一樣）
server:
port: 6002
#數據源
spring:
datasource:
druid:
url: jdbc:mysql://localhost:3306/hub_share_center?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=GMT
driver-class-name: com.mysql.cj.jdbc.Driver
username: root
password: 123456
initial-size: 10
max-active: 50
min-idle: 10
max-wait: 60000
pool-prepared-statements: true
max-pool-prepared-statement-per-connection-size: 20
# mysql 數據庫的特征 會關閉已經連接瞭8個小時的連接
validation-query: SELECT 1 FROM DUAL
application:
name: share-6002
cloud:
nacos:
discovery:
server-addr: 127.0.0.1:8848
# mybatis 配置
mybatis:
# 掃描映射文件
mapper-locations: classpath:mapper/*.xml
configuration:
# 開啟駝峰映射配置
map-underscore-to-camel-case: true
# log
# 整個工程隻答應info 以及以上級別的日志
logging:
level:
root: info
com.csqf.mapper: debug
2.RestTemplate
RestTemplate是Spring Resources中一個訪問第三方RESTful API接口的網絡請求框架。RestTemplate的設計原則和其他Spring Template(例如JdbcTemplate、JmsTemplate)類!，都是為執行復雜任務提供瞭一個具有默認行為的簡單方法。
設置RestTemplate為Bean
springcloud_user_6001中寫一個查詢方法代碼如下（示例）：
@Service
public class UserServiceImpl implements UserService {
@Autowired
private UserMapper userMapper;
@Override
public String getUserById(Integer id) {
User user = userMapper.selectByPrimaryKey(id);
if ("".equals(user)){
return "";
}
return user.getUserName();
}
}
在springcloud_share_6002寫一個DTO（示例）：
繼承Share實力類，加上user中返回的userName
@Data
public class ShareDto extends Share {
private String userName;
}
在springcloud_share_6002中使用RestTemplate調用user並得到userName
@RestController
@RequestMapping("/api/share")
public class ShareContoller {
@Autowired
private ShareServiceImpl shareService;
@Autowired
private RestTemplate restTemplate;
@GetMapping("/{id}")
public R getShareById(@PathVariable("id") Integer id){
Share share = shareService.getShareById(id);
R r = restTemplate.getForObject("http://localhost:6001/api/user/" + share.getUserId(), R.class);
String s = r.getData().toString();
ShareDto shareDto = new ShareDto();
BeanUtils.copyProperties(share,shareDto);
shareDto.setUserName(s);
return new R(ResponseEnum.SUCCESS,shareDto);
}
}
最後訪問swagger（http://localhost:6002/swagger-ui.html）測試得到dto實體類中的對象
總結
nacos的作用就是一個註冊中心，用來管理註冊上來的各個微服務。
到此這篇關於Java之SpringCloud nocos註冊中心講解的文章就介紹到這瞭,更多相關Java之SpringCloud nocos內容請搜索WalkonNet以前的文章或繼續瀏覽下面的相關文章希望大傢以後多多支持WalkonNet！
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