1. Feign applications
Objective: The role of Feign; Using Feign to invoke services in consumer-demo code
Analysis:
- Import starter dependency;
- Turn on Feign function;
- Write Feign client;
- Write a processor ConsumerFeignController, inject Feign client and use it;
- test
Summary:
Feign's primary role: Splicing http request addresses automatically based on parameters.
- Starter dependency;
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>
- Feign client:
//Declare that the current class is a Feign client and specify a service name of user-service
@FeignClient("user-service")
public interface UserClient {
//http://user-service/user/123
@GetMapping("/user/{id}")
User queryById(@PathVariable Long id);
}
2. Feign Load Balancing and Fusing
Target: Feign built-in ribbon configuration item and Hystrix fused Fallback configuration can be configured
Analysis:
- load balancing
- Service Fusion
- Request Compression
- log level
All can be turned on and used in Feign through configuration items.
Summary:
Configuration files in consumer-demo for service consumption engineering:
ribbon:
ConnectTimeout: 1000 # Connection timeout
ReadTimeout: 2000 # Data communication timeout
MaxAutoRetries: 0 # Number of retries for the current server
MaxAutoRetriesNextServer: 0 # How many service retries
OkToRetryOnAllOperations: false # Whether to retry all requests
feign:
hystrix:
enabled: true # Turn on the fusing function of Feign
compression:
request:
enabled: true # Turn on request compression
mime-types: text/html,application/xml,application/json # Set Compressed Data Type
min-request-size: 2048 # Set the lower limit of the size to trigger compression
response:
enabled: true
logging:
level:
com.itheima: debug
3. Introduction to the Spring Cloud Gateway Gateway
Target: Role of the Spring Cloud Gateway Gateway
Summary:
The core of Spring Cloud Gateway is a series of filters that forward client requests to different microservices. Main functions: filtering and routing.
4. Getting started with Spring Cloud Gateway
Goal: Set up Gateway Service Project to test Gateway Service Role
Analysis:
Requirements: Requests containing/user are routed to the gateway system heima-gateway http://127.0.0.1:9091/user/ User id
Steps to achieve:
- Create a project;
- Add starter dependency;
- Write boot class and configuration file;
- Modify the configuration file to set the routing information;
- Start test
http://127.0.0.1:10010/user/8 --> http://127.0.0.1:9091/user/8
Summary:
- Starter Dependency
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-gateway</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
</dependencies>
- configuration file
server:
port: 10010
spring:
application:
name: api-gateway
cloud:
gateway:
routes:
# Route id, can be any
- id: user-service-route
# Service Address of Agent
uri: http://127.0.0.1:9091
# Routing assertion: mapped paths can be matched
predicates:
- Path=/user/**
eureka:
client:
service-url:
defaultZone: http://127.0.0.1:10086/eureka
instance:
prefer-ip-address: true
5. Service-oriented routing
Target: Use services registered in eureka as routing addresses
Analysis:
Writing the routing service address to death is obviously unreasonable; In Spring Cloud Gateway, dynamic routing can be configured to solve this problem.
Summary:
Service-oriented routing; Similar routing paths need to be specified in the configuration file: lb://user-service
Service names written after lb must be registered in eureka to be used
6. Routing prefix processing
Target: You can add or remove prefixes to addresses that request Gateway Services
Analysis:
Address to provide service: http://127.0.0.1:9091/user/8
- Add prefix: The prefix path is added to the request address before it is used as the service address of the proxy;
http://127.0.0.1:10010/8 --> http://127.0.0.1:9091/user/8 Add prefix path/user
- Remove prefix: Remove some prefix paths from the request address before serving as the proxy address;
http://127.0.0.1:10010/api/user/8 --> http://127.0.0.1:9091/user/8 Remove prefix path/api
Summary:
If the client's request address is inconsistent with the service address of the micro service, the path prefix can be added and removed by configuring a path filter.
7. Introduction to filters
Target: Gateway default filter usage and filter type
Summary:
- Usage: Specify the name of the filter to use in the configuration file;
- Type: local, global;
- Use scenarios: request authentication, exception handling, record call duration, and so on.
8. Customize local filters
Target: Write and configure a custom local filter based on the default filter that can get the requested parameter values from the parameter names in the configuration file
Analysis:
Requirements: In the filter (MyParamGatewayFilterFactory), the http://localhost:10010/api/user/8? The value of parameter name in name=itcast is obtained and output to the console; And parameter names are variable, that is, they are not always names; You need to configure parameter names when configuring filters.
Steps to achieve:
- Configure filters;
- Write filters;
- test
Summary:
-
To configure; Configuration is consistent with other filters.
-
Implement filters
package com.itheima.gateway.filter;
import org.springframework.cloud.gateway.filter.GatewayFilter;
import org.springframework.cloud.gateway.filter.factory.AbstractGatewayFilterFactory;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.stereotype.Component;
import java.util.Arrays;
import java.util.List;
@Component
public class MyParamGatewayFilterFactory extends AbstractGatewayFilterFactory<MyParamGatewayFilterFactory.Config> {
static final String PARAM_NAME = "param";
public MyParamGatewayFilterFactory() {
super(Config.class);
}
public List<String> shortcutFieldOrder() {
return Arrays.asList(PARAM_NAME);
}
@Override
public GatewayFilter apply(Config config) {
return (exchange, chain) -> {
// http://localhost:10010/api/user/8?name=itcast config.param ==> name
//Gets the parameter value of the parameter name corresponding to the param in the request parameter
ServerHttpRequest request = exchange.getRequest();
if(request.getQueryParams().containsKey(config.param)){
request.getQueryParams().get(config.param).
forEach(value -> System.out.printf("------------Local filter--------%s = %s------", config.param, value));
}
return chain.filter(exchange);
};
}
public static class Config{
//Corresponds to the parameter name specified when configuring the filter
private String param;
public String getParam() {
return param;
}
public void setParam(String param) {
this.param = param;
}
}
}
9. Customize Global Filters
Target: Define a global filter to check for token parameters in requests
Analysis:
Requirements: Write a global filter that checks if the request address carries a token parameter. If the value of the token parameter exists, it is released. If the parameter value of token is empty or does not exist, set the status code returned to be: unauthorized and no longer executed.
Steps to achieve:
- Write global filters;
- test
Summary:
@Component
public class MyGlobalFilter implements GlobalFilter, Ordered {
@Override
public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
System.out.println("--------------Global filter MyGlobalFilter------------------");
String token = exchange.getRequest().getQueryParams().getFirst("token");
if(StringUtils.isBlank(token)){
//Set response status code to unauthorized
exchange.getResponse().setStatusCode(HttpStatus.UNAUTHORIZED);
return exchange.getResponse().setComplete();
}
return chain.filter(exchange);
}
@Override
public int getOrder() {
//The smaller the value, the earlier the execution
return 1;
}
}
10. Gateway Other Configuration Notes
Target: Load Balancing and Fuse Parameter Configuration for Gateway
Summary:
Gateway Service Profile:
server:
port: 10010
spring:
application:
name: api-gateway
cloud:
gateway:
routes:
# Route id, can be any
- id: user-service-route
# Service Address of Agent
#uri: http://127.0.0.1:9091
# lb represents getting a specific service from eureka
uri: lb://user-service
# Routing assertion: mapped paths can be matched
predicates:
#- Path=/user/**
#- Path=/**
- Path=/api/user/**
filters:
# Add prefix to request path
#- PrefixPath=/user
#1 means filter one path, 2 means two paths, and so on
- StripPrefix=1
- MyParam=name
# Default filter, valid for all routes
default-filters:
- AddResponseHeader=X-Response-Foo, Bar
- AddResponseHeader=abc-myname,heima
globalcors:
corsConfigurations:
'[/**]':
#allowedOrigins: * # Either this or below, * means all
allowedOrigins:
- "http://docs.spring.io"
allowedMethods:
- GET
eureka:
client:
service-url:
defaultZone: http://127.0.0.1:10086/eureka
instance:
prefer-ip-address: true
hystrix:
command:
default:
execution:
isolation:
thread:
timeoutInMilliseconds: 6000
ribbon:
ConnectTimeout: 1000
ReadTimeout: 2000
MaxAutoRetries: 0
MaxAutoRetriesNextServer: 0
Gateway is usually used directly for terminal requests; Feign is typically invoked between microservices.
11. Introduction to Spring Cloud Config Distributed Configuration Center
Target: The role of the Distributed Configuration Center
Summary:
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spring cloud config role: you can modify the configuration files of all other micro services by modifying the configuration files in the git repository.
12. Set up Configuration Center Micro-Service
Target: Create a remote open git repository in CodeCloud, and set up a configuration center micro-service config-server
Analysis:
- Create a git warehouse: Create a warehouse on the code cloud
- Build Configuration Center config-server: Build and configure using spring boot
Summary:
- Configuration Center Dependency
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-config-server</artifactId>
</dependency>
</dependencies>
- Configuration Center Profile
server:
port: 12000
spring:
application:
name: config-server
cloud:
config:
server:
git:
uri: https://gitee.com/goheima/heima-config.git
eureka:
client:
service-url:
defaultZone: http://127.0.0.1:10086/eureka
Modifying the configuration file in gitee will update the configuration center service in time.
13. Get the configuration center configuration
Target: To transform user-service for user micro-service, profile information is no longer provided by the micro-service project, but is obtained from the configuration center
Analysis:
Requirements: Delete the application.yml configuration file of the service provider project user-service and modify it to be obtained from the configuration center config-server.
Steps to achieve:
- Add starter dependency;
- Modify the configuration file;
- Start test
Summary:
Delete the original application.yml; Then add the bootstrap.yml configuration file, which is also the default configuration file for spring boot, whose contents often configure fixed configuration items in some projects. If the project is constantly changing, it should be configured in application.yml, and now using the configuration center, it should be configured in the configuration file for the git repository.
- rely on
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-config</artifactId>
<version>2.1.1.RELEASE</version>
</dependency>
- Configuration file bootstrap.yml
spring:
cloud:
config:
# To be consistent with the application of the configuration file in the repository
name: user
# To be consistent with the profile of the configuration file in the repository
profile: dev
# To be the same version (branch) as the configuration file in the repository
label: master
discovery:
# Use Configuration Center
enabled: true
# Configuration Center Service Name
service-id: config-server
eureka:
client:
service-url:
defaultZone: http://127.0.0.1:10086/eureka
14. Introduction to Spring Cloud Bus
Goal: Understand the role of Spring Cloud Bus
Summary:
Role of Spring Cloud Bus: Update the git repository's configuration file to synchronize to the various microservices in a timely manner without restarting the system.
15. Spring Cloud Bus Applications
Target: Start RabbitMQ to update configuration items in user microservices in a timely manner by sending a Post request after modifying the configuration file in the code cloud
Analysis:
Requirements: Modify the user-dev.yml configuration file in the git repository in CodeCloud to update the configuration file in time without restarting user-service.
Steps to achieve:
- Start RabbitMQ;
- Modify the configuration center config-server;
- Modify service provider project user-service;
- test
Summary:
- Dependent add content for config-server
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-bus</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-stream-binder-rabbit</artifactId>
</dependency>
- Configuration file additions for config-server
server:
port: 12000
spring:
application:
name: config-server
cloud:
config:
server:
git:
uri: https://gitee.com/goheima/heima-config.git
# Configure rabbitmq information; Configuration is not required if both are consistent with defaults
rabbitmq:
host: localhost
port: 5672
username: guest
password: guest
eureka:
client:
service-url:
defaultZone: http://127.0.0.1:10086/eureka
management:
endpoints:
web:
exposure:
# Expose the address of the trigger message bus
include: bus-refresh
- Dependent add content for user-service
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-bus</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-stream-binder-rabbit</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
- Configuration file additions for user-service
# Configure rabbitmq information; Configuration is not required if both are consistent with defaults
rabbitmq:
host: localhost
port: 5672
username: guest
password: guest
- Modification of UserController
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16. Comprehensive application of Spring Cloud system technology
Target: Understand the comprehensive application of Eureka, GateWay, Config, Bus, Feign and other technologies in Spring Cloud
Summary:
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r-rabbit
org.springframework.boot
spring-boot-starter-actuator
- user-service Configuration File Add Content
```yml
# Configure rabbitmq information; Configuration is not required if both are consistent with defaults
rabbitmq:
host: localhost
port: 5672
username: guest
password: guest
- Modification of UserController
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16. Comprehensive application of Spring Cloud system technology
Target: Understand the comprehensive application of Eureka, GateWay, Config, Bus, Feign and other technologies in Spring Cloud
Summary:
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