springboot 应用查询城市天气

作者：程序员欣宸

2022 年 8 月 09 日
本文字数：2376 字
阅读完需：约 8 分钟

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这里分类和汇总了欣宸的全部原创(含配套源码)：https://github.com/zq2599/blog_demos

本篇概览

本文的实战是开发一个 springboot 应用，通过 RestTemplate 获取公共的远程 api 服务，将查询到的指定城市的天气信息返回给前端；

创建 springboot 应用

基于 maven 创建一个 springboot 应用，pom 信息如下，注意添加了 httpclient：

<?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>2.1.2.RELEASE</version>        <relativePath/> <!-- lookup parent from repository -->    </parent>    <groupId>com.bolingcavalry</groupId>    <artifactId>weatherservice</artifactId>    <version>0.0.1-SNAPSHOT</version>    <name>weatherservice</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.apache.httpcomponents</groupId>            <artifactId>httpclient</artifactId>            <version>4.5.7</version>        </dependency>
        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-starter-test</artifactId>            <scope>test</scope>        </dependency>    </dependencies>
    <build>        <plugins>            <plugin>                <groupId>org.springframework.boot</groupId>                <artifactId>spring-boot-maven-plugin</artifactId>            </plugin>        </plugins>    </build></project>

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启动类如下：

package com.bolingcavalry.weatherservice;
import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplicationpublic class WeatherserviceApplication {    public static void main(String[] args) {        SpringApplication.run(WeatherserviceApplication.class, args);    }}

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创建配置类

创建一个配置类，这里注意要使用 HttpComponentsClientHttpRequestFactory 作为 RestTemplate 构造方法的入参，这样才能支持 gzip 压缩的 response，否则得到的就是乱码：

package com.bolingcavalry.weatherservice;
import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;import org.springframework.http.converter.StringHttpMessageConverter;import org.springframework.web.client.RestTemplate;import java.nio.charset.StandardCharsets;

@Configurationpublic class WeatherConfig {    @Bean    public RestTemplate restTemplate(){        RestTemplate restTemplate = new RestTemplate(new HttpComponentsClientHttpRequestFactory());        restTemplate.getMessageConverters().set(1, new StringHttpMessageConverter(StandardCharsets.UTF_8));        return restTemplate;    }}

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创建 controller

创建一个 controller 来接收 web 请求，然后发起气象服务网站发起天气查询：

package com.bolingcavalry.weatherservice.controller;
import org.springframework.beans.factory.annotation.Autowired;import org.springframework.http.*;import org.springframework.web.bind.annotation.PathVariable;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RequestMethod;import org.springframework.web.bind.annotation.RestController;import org.springframework.web.client.RestTemplate;
@RestControllerpublic class QueryWeather {
    @Autowired    RestTemplate restTemplate;
    @RequestMapping(value = "/get/{city}", method = RequestMethod.GET)    public String extern(@PathVariable("city") String city){        String apiURL = "http://wthrcdn.etouch.cn/weather_mini?city=" + city;        ResponseEntity<String> responseEntity = restTemplate.getForEntity(apiURL, String.class);
        if(200==responseEntity.getStatusCodeValue()){            return responseEntity.getBody();        }else{            return "error with code : " + responseEntity.getStatusCodeValue();        }    }}