idea installs three plug-ins first
MavenHelper

Spring Cloud

introduce

spring cloud is a collection of frameworks. Taking advantage of the development convenience of spring boot, it cleverly simplifies the development of distributed system infrastructure, such as service discovery and registration, configuration center, message bus, load balancing, circuit breaker, data monitoring, etc., which can be started and deployed with one click with the development style of spring boot. spring cloud does not repeatedly manufacture wheels. It just combines the relatively mature and practical service frameworks developed by various companies, repackages them through the spring boot style, shields the complex configuration and implementation principles, and finally leaves a set of distributed system development kit that is easy to understand, deploy and maintain for developers.

Spring cloud is a blessing for small and medium-sized Internet companies, because such companies often do not have the strength or sufficient capital investment to develop their own distributed system infrastructure. Using spring cloud one-stop solution can not only calmly deal with business development, but also greatly reduce development costs. At the same time, with the popularity of microservice architecture and docker container concept in recent years, spring cloud will also have a place in the future more and more "cloud" software development style. In particular, it provides standardized and one-stop technical solutions in the current variety of distributed solutions, which may be as meaningful as the birth of servlet specification in that year, Effectively promote the progress of the technical level of the server software system.

Technical composition

• eureka
  Microservice governance, service registration and discovery

• ribbon
  Load balancing, request retry

• hystrix
  Circuit breaker, service degradation, fusing

• feign
  ribbon + hystrix integration and declarative client

• hystrix dashboard and turbine
  hystrix data monitoring

• zuul
  API gateway provides a unified entrance to microservices and unified permission verification

• config
  Configuration center

• bus
  Message bus, configuration refresh

• sleuth+zipkin
  Link tracking

Spring Cloud vs. Dubbo

Dubbo

Dubbo is just a remote call (RPC) framework
By default, it is based on long connection and supports multiple serialization formats
Spring Cloud

Frame set
Provides a complete set of microservice solutions (family bucket)
http based call, Rest API

1, service - service

• item service, port 8001
• user service, port 8101
• order service, port 8201
  

2, commons common project

New maven project

pom.xml

<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>cn.tedu</groupId>
	<artifactId>sp01-commons</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>sp01-commons</name>
	<dependencies>
		<dependency>
			<groupId>com.fasterxml.jackson.module</groupId>
			<artifactId>jackson-module-parameter-names</artifactId>
			<version>2.9.8</version>
		</dependency>
		<dependency>
			<groupId>com.fasterxml.jackson.datatype</groupId>
			<artifactId>jackson-datatype-jdk8</artifactId>
			<version>2.9.8</version>
		</dependency>
		<dependency>
			<groupId>com.fasterxml.jackson.datatype</groupId>
			<artifactId>jackson-datatype-jsr310</artifactId>
			<version>2.9.8</version>
		</dependency>
		<dependency>
			<groupId>com.fasterxml.jackson.datatype</groupId>
			<artifactId>jackson-datatype-guava</artifactId>
			<version>2.9.8</version>
		</dependency>

		<dependency>
			<groupId>org.projectlombok</groupId>
			<artifactId>lombok</artifactId>
			<version>1.18.6</version>
		</dependency>
		<dependency>
			<groupId>javax.servlet</groupId>
			<artifactId>javax.servlet-api</artifactId>
			<version>3.1.0</version>
		</dependency>
		<dependency>
			<groupId>org.slf4j</groupId>
			<artifactId>slf4j-api</artifactId>
			<version>1.7.26</version>
		</dependency>
		<dependency>
		    <groupId>org.apache.commons</groupId>
		    <artifactId>commons-lang3</artifactId>
		    <version>3.9</version>
		</dependency>

	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-compiler-plugin</artifactId>
				<version>3.8.0</version>
				<configuration>
					<source>1.8</source>
					<target>1.8</target>
				</configuration>
			</plugin>
		</plugins>
	</build>
</project>

java source file

pojo

Item

package cn.tedu.sp01.pojo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@NoArgsConstructor
@AllArgsConstructor
public class Item {
	private Integer id;
	private String name;
	private Integer number;
}

User

package cn.tedu.sp01.pojo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@NoArgsConstructor
@AllArgsConstructor
public class User {
	private Integer id;
	private String username;
	private String password;
}

Order

package cn.tedu.sp01.pojo;

import java.util.List;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@NoArgsConstructor
@AllArgsConstructor
public class Order {
	private String id;
	private User user;
	private List<Item> items;
}

service

ItemService

package cn.tedu.sp01.service;

import java.util.List;

import cn.tedu.sp01.pojo.Item;

public interface ItemService {
	List<Item> getItems(String orderId);
	void decreaseNumbers(List<Item> list);
}

UserService

package cn.tedu.sp01.service;

import cn.tedu.sp01.pojo.User;

public interface UserService {
	User getUser(Integer id);
	void addScore(Integer id, Integer score);
}

OrderService

package cn.tedu.sp01.service;


import cn.tedu.sp01.pojo.Order;

public interface OrderService {
	Order getOrder(String orderId);
	void addOrder(Order order);
}

util
CookieUtil

package cn.tedu.web.util;

import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class CookieUtil {

	/**
	 * @param response
	 * @param name
	 * @param value
	 * @param maxAge
	 */
	public static void setCookie(HttpServletResponse response,
			String name, String value, String domain, String path, int maxAge) {
		Cookie cookie = new Cookie(name, value);
		if(domain != null) {
			cookie.setDomain(domain);
		}
		cookie.setPath(path);
		cookie.setMaxAge(maxAge);
		response.addCookie(cookie);
	}
	public static void setCookie(HttpServletResponse response, String name, String value, int maxAge) {
		setCookie(response, name, value, null, "/", maxAge);
	}
	public static void setCookie(HttpServletResponse response, String name, String value) {
		setCookie(response, name, value, null, "/", 3600);
	}
	public static void setCookie(HttpServletResponse response, String name) {
		setCookie(response, name, "", null, "/", 3600);
	}

	/**
	 * @param request
	 * @param name
	 * @return
	 */
	public static String getCookie(HttpServletRequest request, String name) {
		String value = null;
		Cookie[] cookies = request.getCookies();
		if (null != cookies) {
			for (Cookie cookie : cookies) {
				if (cookie.getName().equals(name)) {
					value = cookie.getValue();
				}
			}
		}
		return value;
	}

	/**
	 * @param response
	 * @param name
	 * @return
	 */
	public static void removeCookie(HttpServletResponse response, String name, String domain, String path) {
		setCookie(response, name, "", domain, path, 0);
	}

}

JsonUtil

package cn.tedu.web.util;

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Writer;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.net.URL;
import java.nio.charset.StandardCharsets;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.List;

import org.apache.commons.lang3.StringUtils;

import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.fasterxml.jackson.databind.node.ObjectNode;
import com.fasterxml.jackson.datatype.guava.GuavaModule;
import com.fasterxml.jackson.datatype.jdk8.Jdk8Module;
import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
import com.fasterxml.jackson.module.paramnames.ParameterNamesModule;

import lombok.extern.slf4j.Slf4j;

@Slf4j
public class JsonUtil {
    private static ObjectMapper mapper;
    private static JsonInclude.Include DEFAULT_PROPERTY_INCLUSION = JsonInclude.Include.NON_DEFAULT;
    private static boolean IS_ENABLE_INDENT_OUTPUT = false;
    private static String CSV_DEFAULT_COLUMN_SEPARATOR = ",";
    static {
        try {
            initMapper();
            configPropertyInclusion();
            configIndentOutput();
            configCommon();
        } catch (Exception e) {
            log.error("jackson config error", e);
        }
    }

    private static void initMapper() {
        mapper = new ObjectMapper();
    }

    private static void configCommon() {
        config(mapper);
    }

    private static void configPropertyInclusion() {
        mapper.setSerializationInclusion(DEFAULT_PROPERTY_INCLUSION);
    }

    private static void configIndentOutput() {
        mapper.configure(SerializationFeature.INDENT_OUTPUT, IS_ENABLE_INDENT_OUTPUT);
    }

    private static void config(ObjectMapper objectMapper) {
        objectMapper.enable(JsonGenerator.Feature.WRITE_BIGDECIMAL_AS_PLAIN);
        objectMapper.enable(DeserializationFeature.ACCEPT_EMPTY_STRING_AS_NULL_OBJECT);
        objectMapper.enable(DeserializationFeature.ACCEPT_SINGLE_VALUE_AS_ARRAY);
        objectMapper.enable(DeserializationFeature.FAIL_ON_READING_DUP_TREE_KEY);
        objectMapper.enable(DeserializationFeature.FAIL_ON_NUMBERS_FOR_ENUMS);
        objectMapper.disable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES);
        objectMapper.disable(DeserializationFeature.FAIL_ON_NULL_FOR_PRIMITIVES);
        objectMapper.disable(SerializationFeature.FAIL_ON_EMPTY_BEANS);
        objectMapper.enable(JsonParser.Feature.ALLOW_COMMENTS);
        objectMapper.disable(JsonGenerator.Feature.ESCAPE_NON_ASCII);
        objectMapper.enable(JsonGenerator.Feature.IGNORE_UNKNOWN);
        objectMapper.enable(JsonParser.Feature.ALLOW_UNQUOTED_FIELD_NAMES);
        objectMapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
        objectMapper.setDateFormat(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"));
        objectMapper.enable(JsonParser.Feature.ALLOW_SINGLE_QUOTES);
        objectMapper.registerModule(new ParameterNamesModule());
        objectMapper.registerModule(new Jdk8Module());
        objectMapper.registerModule(new JavaTimeModule());
        objectMapper.registerModule(new GuavaModule());
    }
    public static void setSerializationInclusion(JsonInclude.Include inclusion) {
        DEFAULT_PROPERTY_INCLUSION = inclusion;
        configPropertyInclusion();
    }

    public static void setIndentOutput(boolean isEnable) {
        IS_ENABLE_INDENT_OUTPUT = isEnable;
        configIndentOutput();
    }

    public static <V> V from(URL url, Class<V> c) {
        try {
            return mapper.readValue(url, c);
        } catch (IOException e) {
            log.error("jackson from error, url: {}, type: {}", url.getPath(), c, e);
            return null;
        }
    }

    public static <V> V from(InputStream inputStream, Class<V> c) {
        try {
            return mapper.readValue(inputStream, c);
        } catch (IOException e) {
            log.error("jackson from error, type: {}", c, e);
            return null;
        }
    }

    public static <V> V from(File file, Class<V> c) {
        try {
            return mapper.readValue(file, c);
        } catch (IOException e) {
            log.error("jackson from error, file path: {}, type: {}", file.getPath(), c, e);
            return null;
        }
    }

    public static <V> V from(Object jsonObj, Class<V> c) {
        try {
            return mapper.readValue(jsonObj.toString(), c);
        } catch (IOException e) {
            log.error("jackson from error, json: {}, type: {}", jsonObj.toString(), c, e);
            return null;
        }
    }

    public static <V> V from(String json, Class<V> c) {
        try {
            return mapper.readValue(json, c);
        } catch (IOException e) {
            log.error("jackson from error, json: {}, type: {}", json, c, e);
            return null;
        }
    }

    public static <V> V from(URL url, TypeReference<V> type) {
        try {
            return mapper.readValue(url, type);
        } catch (IOException e) {
            log.error("jackson from error, url: {}, type: {}", url.getPath(), type, e);
            return null;
        }
    }

    public static <V> V from(InputStream inputStream, TypeReference<V> type) {
        try {
            return mapper.readValue(inputStream, type);
        } catch (IOException e) {
            log.error("jackson from error, type: {}", type, e);
            return null;
        }
    }

    public static <V> V from(File file, TypeReference<V> type) {
        try {
            return mapper.readValue(file, type);
        } catch (IOException e) {
            log.error("jackson from error, file path: {}, type: {}", file.getPath(), type, e);
            return null;
        }
    }

    public static <V> V from(Object jsonObj, TypeReference<V> type) {
        try {
            return mapper.readValue(jsonObj.toString(), type);
        } catch (IOException e) {
            log.error("jackson from error, json: {}, type: {}", jsonObj.toString(), type, e);
            return null;
        }
    }

    public static <V> V from(String json, TypeReference<V> type) {
        try {
            return mapper.readValue(json, type);
        } catch (IOException e) {
            log.error("jackson from error, json: {}, type: {}", json, type, e);
            return null;
        }
    }

    public static <V> String to(List<V> list) {
        try {
            return mapper.writeValueAsString(list);
        } catch (JsonProcessingException e) {
            log.error("jackson to error, obj: {}", list, e);
            return null;
        }
    }

    public static <V> String to(V v) {
        try {
            return mapper.writeValueAsString(v);
        } catch (JsonProcessingException e) {
            log.error("jackson to error, obj: {}", v, e);
            return null;
        }
    }

    public static <V> void toFile(String path, List<V> list) {
        try (Writer writer = new FileWriter(new File(path), true)) {
            mapper.writer().writeValues(writer).writeAll(list);
            writer.flush();
        } catch (Exception e) {
            log.error("jackson to file error, path: {}, list: {}", path, list, e);
        }
    }

    public static <V> void toFile(String path, V v) {
        try (Writer writer = new FileWriter(new File(path), true)) {
            mapper.writer().writeValues(writer).write(v);
            writer.flush();
        } catch (Exception e) {
            log.error("jackson to file error, path: {}, obj: {}", path, v, e);
        }
    }

    public static String getString(String json, String key) {
        if (StringUtils.isEmpty(json)) {
            return null;
        }
        try {
            JsonNode node = mapper.readTree(json);
            if (null != node) {
                return node.get(key).toString();
            } else {
                return null;
            }
        } catch (IOException e) {
            log.error("jackson get string error, json: {}, key: {}", json, key, e);
            return null;
        }
    }

    public static Integer getInt(String json, String key) {
        if (StringUtils.isEmpty(json)) {
            return null;
        }
        try {
            JsonNode node = mapper.readTree(json);
            if (null != node) {
                return node.get(key).intValue();
            } else {
                return null;
            }
        } catch (IOException e) {
            log.error("jackson get int error, json: {}, key: {}", json, key, e);
            return null;
        }
    }

    public static Long getLong(String json, String key) {
        if (StringUtils.isEmpty(json)) {
            return null;
        }
        try {
            JsonNode node = mapper.readTree(json);
            if (null != node) {
                return node.get(key).longValue();
            } else {
                return null;
            }
        } catch (IOException e) {
            log.error("jackson get long error, json: {}, key: {}", json, key, e);
            return null;
        }
    }

    public static Double getDouble(String json, String key) {
        if (StringUtils.isEmpty(json)) {
            return null;
        }
        try {
            JsonNode node = mapper.readTree(json);
            if (null != node) {
                return node.get(key).doubleValue();
            } else {
                return null;
            }
        } catch (IOException e) {
            log.error("jackson get double error, json: {}, key: {}", json, key, e);
            return null;
        }
    }

    public static BigInteger getBigInteger(String json, String key) {
        if (StringUtils.isEmpty(json)) {
            return new BigInteger(String.valueOf(0.00));
        }
        try {
            JsonNode node = mapper.readTree(json);
            if (null != node) {
                return node.get(key).bigIntegerValue();
            } else {
                return null;
            }
        } catch (IOException e) {
            log.error("jackson get biginteger error, json: {}, key: {}", json, key, e);
            return null;
        }
    }

    public static BigDecimal getBigDecimal(String json, String key) {
        if (StringUtils.isEmpty(json)) {
            return null;
        }
        try {
            JsonNode node = mapper.readTree(json);
            if (null != node) {
                return node.get(key).decimalValue();
            } else {
                return null;
            }
        } catch (IOException e) {
            log.error("jackson get bigdecimal error, json: {}, key: {}", json, key, e);
            return null;
        }
    }

    public static boolean getBoolean(String json, String key) {
        if (StringUtils.isEmpty(json)) {
            return false;
        }
        try {
            JsonNode node = mapper.readTree(json);
            if (null != node) {
                return node.get(key).booleanValue();
            } else {
                return false;
            }
        } catch (IOException e) {
            log.error("jackson get boolean error, json: {}, key: {}", json, key, e);
            return false;
        }
    }

    public static byte[] getByte(String json, String key) {
        if (StringUtils.isEmpty(json)) {
            return null;
        }
        try {
            JsonNode node = mapper.readTree(json);
            if (null != node) {
                return node.get(key).binaryValue();
            } else {
                return null;
            }
        } catch (IOException e) {
            log.error("jackson get byte error, json: {}, key: {}", json, key, e);
            return null;
        }
    }

    public static <T> ArrayList<T> getList(String json, String key) {
        if (StringUtils.isEmpty(json)) {
            return null;
        }
        String string = getString(json, key);
        return from(string, new TypeReference<ArrayList<T>>() {});
    }

    public static <T> String add(String json, String key, T value) {
        try {
            JsonNode node = mapper.readTree(json);
            add(node, key, value);
            return node.toString();
        } catch (IOException e) {
            log.error("jackson add error, json: {}, key: {}, value: {}", json, key, value, e);
            return json;
        }
    }

    private static <T> void add(JsonNode jsonNode, String key, T value) {
        if (value instanceof String) {
            ((ObjectNode) jsonNode).put(key, (String) value);
        } else if (value instanceof Short) {
            ((ObjectNode) jsonNode).put(key, (Short) value);
        } else if (value instanceof Integer) {
            ((ObjectNode) jsonNode).put(key, (Integer) value);
        } else if (value instanceof Long) {
            ((ObjectNode) jsonNode).put(key, (Long) value);
        } else if (value instanceof Float) {
            ((ObjectNode) jsonNode).put(key, (Float) value);
        } else if (value instanceof Double) {
            ((ObjectNode) jsonNode).put(key, (Double) value);
        } else if (value instanceof BigDecimal) {
            ((ObjectNode) jsonNode).put(key, (BigDecimal) value);
        } else if (value instanceof BigInteger) {
            ((ObjectNode) jsonNode).put(key, (BigInteger) value);
        } else if (value instanceof Boolean) {
            ((ObjectNode) jsonNode).put(key, (Boolean) value);
        } else if (value instanceof byte[]) {
            ((ObjectNode) jsonNode).put(key, (byte[]) value);
        } else {
            ((ObjectNode) jsonNode).put(key, to(value));
        }
    }

    public static String remove(String json, String key) {
        try {
            JsonNode node = mapper.readTree(json);
            ((ObjectNode) node).remove(key);
            return node.toString();
        } catch (IOException e) {
            log.error("jackson remove error, json: {}, key: {}", json, key, e);
            return json;
        }
    }

    public static <T> String update(String json, String key, T value) {
        try {
            JsonNode node = mapper.readTree(json);
            ((ObjectNode) node).remove(key);
            add(node, key, value);
            return node.toString();
        } catch (IOException e) {
            log.error("jackson update error, json: {}, key: {}, value: {}", json, key, value, e);
            return json;
        }
    }

    public static String format(String json) {
        try {
            JsonNode node = mapper.readTree(json);
            return mapper.writerWithDefaultPrettyPrinter().writeValueAsString(node);
        } catch (IOException e) {
            log.error("jackson format json error, json: {}", json, e);
            return json;
        }
    }

    public static boolean isJson(String json) {
        try {
            mapper.readTree(json);
            return true;
        } catch (Exception e) {
            log.error("jackson check json error, json: {}", json, e);
            return false;
        }
    }

    private static InputStream getResourceStream(String name) {
        return JsonUtil.class.getClassLoader().getResourceAsStream(name);
    }

    private static InputStreamReader getResourceReader(InputStream inputStream) {
        if (null == inputStream) {
            return null;
        }
        return new InputStreamReader(inputStream, StandardCharsets.UTF_8);
    }
}

JsonResult

package cn.tedu.web.util;

import lombok.Getter;
import lombok.Setter;

@Getter
@Setter
public class JsonResult<T> {
	/** success */
	public static final int SUCCESS = 200;

	/** not logged on */
	public static final int NOT_LOGIN = 400;

	/** exception occurred */
	public static final int EXCEPTION = 401;

	/** System error */
	public static final int SYS_ERROR = 402;

	/** Parameter error */
	public static final int PARAMS_ERROR = 403;

	/** Unsupported or obsolete */
	public static final int NOT_SUPPORTED = 410;

	/** AuthCode error */
	public static final int INVALID_AUTHCODE = 444;

	/** Too frequent calls */
	public static final int TOO_FREQUENT = 445;

	/** unknown error */
	public static final int UNKNOWN_ERROR = 499;
	
	private int code;
	private String msg;
	private T data;
	
	

	public static JsonResult build() {
		return new JsonResult();
	}
	public static JsonResult build(int code) {
		return new JsonResult().code(code);
	}
	public static JsonResult build(int code, String msg) {
		return new JsonResult<String>().code(code).msg(msg);
	}
	public static <T> JsonResult<T> build(int code, T data) {
		return new JsonResult<T>().code(code).data(data);
	}
	public static <T> JsonResult<T> build(int code, String msg, T data) {
		return new JsonResult<T>().code(code).msg(msg).data(data);
	}
	
	public JsonResult<T> code(int code) {
		this.code = code;
		return this;
	}
	public JsonResult<T> msg(String msg) {
		this.msg = msg;
		return this;
	}
	public JsonResult<T> data(T data) {
		this.data = data;
		return this;
	}
	
	
	public static JsonResult ok() {
		return build(SUCCESS);
	}
	public static JsonResult ok(String msg) {
		return build(SUCCESS, msg);
	}
	public static <T> JsonResult<T> ok(T data) {
		return build(SUCCESS, data);
	}
	public static JsonResult err() {
		return build(EXCEPTION);
	}
	public static JsonResult err(String msg) {
		return build(EXCEPTION, msg);
	}
	
	@Override
	public String toString() {
		return JsonUtil.to(this);
	}
}

3, item service

New project

Configuration dependency pom.xml
Configure application.yml
Configure main program
Write code

New spring boot start project

Select dependencies

Select web only

pom.xml

Add SP01 commons project dependency

<?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 https://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>2.2.1.RELEASE</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>cn.tedu</groupId>
	<artifactId>sp02-itemservice</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>sp02-itemservice</name>
	<description>Demo project for Spring Boot</description>

	<properties>
		<java.version>1.8</java.version>
	</properties>

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

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
			<exclusions>
				<exclusion>
					<groupId>org.junit.vintage</groupId>
					<artifactId>junit-vintage-engine</artifactId>
				</exclusion>
			</exclusions>
		</dependency>
		<dependency>
			<groupId>cn.tedu</groupId>
			<artifactId>sp01-commons</artifactId>
			<version>0.0.1-SNAPSHOT</version>
		</dependency>
	</dependencies>

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

application.yml

# application.yml
# yml -yaml -yet annother markup

# Name registered with the registry
spring:
  application:
    name: item-service
# item   8001
# user   8101
# order  8201
server:
  port: 8001

main program

The default code does not need to be modified

package cn.tedu.sp02;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class Sp02ItemserviceApplication {

	public static void main(String[] args) {
		SpringApplication.run(Sp02ItemserviceApplication.class, args);
	}

}

java source file

ItemServiceImpl

package cn.tedu.sp02.item.service;

import java.util.ArrayList;
import java.util.List;

import org.springframework.stereotype.Service;

import cn.tedu.sp01.pojo.Item;
import cn.tedu.sp01.service.ItemService;

import lombok.extern.slf4j.Slf4j;

@Slf4j
@Service
public class ItemServiceImpl implements ItemService {

	@Override
	public List<Item> getItems(String orderId) {
		ArrayList<Item> list = new ArrayList<Item>();
		list.add(new Item(1, "Commodity 1",1));
		list.add(new Item(2, "Commodity 2",2));
		list.add(new Item(3, "Commodity 3",3));
		list.add(new Item(4, "Commodity 4",4));
		list.add(new Item(5, "Commodity 5",5));
		return list;
	}

	@Override
	public void decreaseNumbers(List<Item> list) {
		for(Item item : list) {
			log.info("reduce stock - "+item);
		}
	}
}

ItemController

package cn.tedu.sp02.item.controller;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RestController;

import cn.tedu.sp01.pojo.Item;
import cn.tedu.sp01.service.ItemService;
import cn.tedu.web.util.JsonResult;

import lombok.extern.slf4j.Slf4j;

@Slf4j
@RestController
public class ItemController {
	@Autowired
	private ItemService itemService;
	
	@Value("${server.port}")
	private int port;
	
	@GetMapping("/{orderId}")
	public JsonResult<List<Item>> getItems(@PathVariable String orderId) {
		log.info("server.port="+port+", orderId="+orderId);
		
		List<Item> items = itemService.getItems(orderId);
		return JsonResult.ok(items).msg("port="+port);
	}
	
	@PostMapping("/decreaseNumber")
	public JsonResult decreaseNumber(@RequestBody List<Item> items) {
		itemService.decreaseNumbers(items);
		return JsonResult.ok();
	}
}

Several annotations of Spring MVC receiving parameters

Access test
Query the goods according to orderid
http://localhost:8001/35

Reduce commodity inventory

http://localhost:8001/decreaseNumber

Using postman, POST sends data in the following format:

[{"id":1, "name":"abc", "number":23},{"id":2, "name":"def", "number":11}]