用RestTemplate调用第三方提供的API接口

迷南。 2022-11-10 03:51 346阅读 0赞

首先按照惯例分享一个提供免费接口的网站:  
[聚合数据][Link 1]  
直接点击去自己注册个账号申请个免费的接口测试

今天用RestTemplate调一个天气预报的接口  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1Rhb1NoYW81MjE_size_16_color_FFFFFF_t_70]  
申请之后记住这个key后面拼装url会用  
建议直接写在配置文件里  
先看API文档介绍  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1Rhb1NoYW81MjE_size_16_color_FFFFFF_t_70 1]  
很清晰看到该接口请求方式支持get或者post  
**在看请求示例 :**  
后面带着两个请求参数 这个地方这两个参数顺序前后无所谓  
下面直接来代码:  
先弄个key的属性类

/** * 类说明: * 〈天气预报接口key〉 * * @Author: wlt * @Date: 2021/3/15 10:11 */
 @Data
 public class WeatherProp extends BaseBean { 
 /** * 调用接口key */
 private String key;
 
 }

yml配置文件里需要加上

pangu-weather:
        weatherprop:
            key: xxxxxxxxxxxxxxxx

然后配置类

/** * 类说明: * 〈天气接口属性配置〉 * * @Author: wlt * @Date: 2021/3/15 10:36 */
 @Configuration
 public class ApplicationWeatherConfig { 
 @Bean
 @ConfigurationProperties(prefix = "pangu-weather.weatherprop")
 public WeatherProp weatherProp() { 
 return new WeatherProp();
 }
 }

以上就可以在启动的时候这个属性类就会当成一个bean注入到容器里了  
接下来就是拼装这个url调用了

/** * 类说明: * 〈天气预报处理程序〉 * * @Author: wlt * @Date: 2021/3/15 10:04 */
 @Slf4j
 @Component("weatherHandler")
 public class WeatherHandler implements InitializingBean { 
 /** * 调用聚合数据接口应答errcode: 0 ：请求成功 */
 public static final int RPC_CODE_SUCCESS = 0;
 /** * 调用聚合数据接口应答errcode: 207301 ：错误的查询城市名 */
 public static final int RPC_CODE_WRONG_CITY = 207301;
 /** * 调用聚合数据接口应答errcode: 207302 ：查询不到该城市的相关信息 */
 public static final int RPC_CODE_NOT_FOUND_CITY = 207302;
 /** * 调用聚合数据接口应答errcode: 207303 ：网络错误，请重试 */
 public static final int RPC_CODE_NETWORK_ERROR= 207303;
 
 @Resource(name = "weatherProp")
 private WeatherProp weatherProp;
 
 @Resource(name = "restTemplate")
 private RestTemplate restTemplate;
 /** * 请求地址 */
 private String url;
 
 @Override
 public void afterPropertiesSet() throws Exception { 
 StringBuilder urlSb = new StringBuilder();
 urlSb.append("http://apis.juhe.cn/simpleWeather/query?");
 urlSb.append("key=").append(weatherProp.getKey());
 this.url = urlSb.toString();
 }
 /** * 功能描述: * <查询天气> * @Param [city] * @return 应答消息 * @Author: wlt * @Date: 2021/3/15 11:10 **/
 public WeatherVO weather(String city) { 
 log.debug("param city : {}", city);
 String reqUrl = url + "&city=" + city;
 System.out.println(reqUrl);
 String responseStr = restTemplate.getForObject(reqUrl, String.class);
 log.debug("code： {}, responseStr : {}", city, responseStr);
 WeatherVO weather = JsonUtil.readValue(responseStr, WeatherVO.class);
 return weather;
 }
 
 }

**其实就是这么一句话完成了调用**  
String responseStr = restTemplate.getForObject(reqUrl, String.class);  
这个地方得注意啊API返回的JSON示例

{ 
        "reason": "查询成功",
        "result": { 
            "city": "苏州",
            "realtime": { 
                "temperature": "4",
                "humidity": "82",
                "info": "阴",
                "wid": "02",
                "direct": "西北风",
                "power": "3级",
                "aqi": "80"
            },
            "future": [
                { 
                    "date": "2019-02-22",
                    "temperature": "1/7℃",
                    "weather": "小雨转多云",
                    "wid": { 
                        "day": "07",
                        "night": "01"
                    },
                    "direct": "北风转西北风"
                },
                { 
                    "date": "2019-02-23",
                    "temperature": "2/11℃",
                    "weather": "多云转阴",
                    "wid": { 
                        "day": "01",
                        "night": "02"
                    },
                    "direct": "北风转东北风"
                },
                { 
                    "date": "2019-02-24",
                    "temperature": "6/12℃",
                    "weather": "多云",
                    "wid": { 
                        "day": "01",
                        "night": "01"
                    },
                    "direct": "东北风转北风"
                },
                { 
                    "date": "2019-02-25",
                    "temperature": "5/12℃",
                    "weather": "小雨转多云",
                    "wid": { 
                        "day": "07",
                        "night": "01"
                    },
                    "direct": "东北风"
                },
                { 
                    "date": "2019-02-26",
                    "temperature": "5/11℃",
                    "weather": "多云转小雨",
                    "wid": { 
                        "day": "01",
                        "night": "07"
                    },
                    "direct": "东北风"
                }
            ]
        },
        "error_code": 0
    }

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1Rhb1NoYW81MjE_size_16_color_FFFFFF_t_70 2]  
result其实是个Object  
返回的实体类

/** * 类说明: * 〈返回json数据〉 * * @Author: wlt * @Date: 2021/3/15 10:02 */
 @Data
 public class WeatherVO extends BaseBean { 
 private static final long serialVersionUID = 6788688600990722529L;
 /** * <返回码，0为查询成功> **/
 private int error_code;
 /** * <返回说明> **/
 private String reason;
 /** * <返回结果集> **/
 private Object result;
 }

接下来就是Controller  
注意我用的是DDD领域驱动设计模式写起来很麻烦 我就简单复制下代码你们参考一下即可

/** * 功能描述: * <根据城市查询天气> * @Param [form] * @return 应答消息 * @Author: wlt * @Date: 2021/3/15 14:12 **/
 @PostMapping(path = "/company/workflow/drivelog/queryCityWeather", produces = MediaType.APPLICATION_JSON_UTF8_VALUE)
 public ResponseMessage<WeatherDTO> queryCityWeather(@RequestBody WeatherForm form) { 
 ResponseMessage<WeatherEntity> result = drivelogAppService.queryCityWeather(form);
 if (ResponseCheckUtil.failed(result)) { 
 return ResponseMessageUtil.genResult(result.getCode(), result.getMsg());
 }
 WeatherDTO weatherDTO = DrivelogAssembler.toWeatherDTO(result.getData());
 return ResponseMessageUtil.genSuccessResult(weatherDTO);
 }

APPService代码

DomainService代码

/** * 功能描述: * <根据城市查询天气> * @Param [city] * @return 应答消息 * @Author: wlt * @Date: 2021/3/15 11:23 **/
 public ResponseMessage<WeatherEntity> queryCityWeather(WeatherForm form) { 
 //调聚合数据接口查询天气预报
 WeatherVO response = weatherHandler.weather(form.getCity());
 Integer errorCode = Integer.valueOf(response.getError_code());
 if (errorCode != WeatherHandler.RPC_CODE_SUCCESS) { 
 Res01012Weather res01012Weather = weatherMap.get(errorCode);
 if (res01012Weather != null) { 
 return ResponseMessageUtil.genResult(res01012Weather);
 }
 return ResponseMessageUtil.genFailResult();
 }
 //object转实体类
 Object result = response.getResult();
 ObjectMapper objectMapper = new ObjectMapper();
 WeatherEntity weatherEntity = objectMapper.convertValue(result, WeatherEntity.class);
 return ResponseMessageUtil.genSuccessResult(weatherEntity);
 }
 
 @Override
 public void afterPropertiesSet() throws Exception { 
 weatherMap = new HashMap<>();
 weatherMap.put(WeatherHandler.RPC_CODE_WRONG_CITY,Res01012Weather.RPC_CODE_WRONG_CITY);
 weatherMap.put(WeatherHandler.RPC_CODE_NOT_FOUND_CITY,Res01012Weather.RPC_CODE_NOT_FOUND_CITY);
 weatherMap.put(WeatherHandler.RPC_CODE_NETWORK_ERROR,Res01012Weather.RPC_CODE_NETWORK_ERROR);
 }

我把API上的错误码改成了我们自己项目设定的错误码 
前面需要定义一个全局的map 
private Map<Integer, Res01012Weather> weatherMap; 
**解释:** 
afterPropertiesSet这个方法来自接口InitializingBean 
**源码注释:** 
设置所有bean属性后，由包含的\{@code BeanFactory\}调用 
并满意\{@link BeanFactoryAware\}，\{@ code ApplicationContextAware\}等。

此方法允许Bean实例对其整体执行验证 设置了所有bean属性后，进行配置和最终初始化。 如果配置错误（例如无法设置 必要属性），或者如果初始化由于任何其他原因而失败

**测试接口:**

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1Rhb1NoYW81MjE_size_16_color_FFFFFF_t_70 3]

**控制台打印日志**

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1Rhb1NoYW81MjE_size_16_color_FFFFFF_t_70 4]

[Link 1]: https://www.juhe.cn/
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1Rhb1NoYW81MjE_size_16_color_FFFFFF_t_70]: /images/20221023/1b7143c02c13463cad85a6d34f128d79.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1Rhb1NoYW81MjE_size_16_color_FFFFFF_t_70 1]: /images/20221023/0c82aff0d99c41ceabc9db473e8d6e3e.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1Rhb1NoYW81MjE_size_16_color_FFFFFF_t_70 2]: /images/20221023/4a9cc1bb868e41bbb791d044d54c92bf.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1Rhb1NoYW81MjE_size_16_color_FFFFFF_t_70 3]: /images/20221023/ecb4e5abb65e43ef89e9d131f1177ff8.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1Rhb1NoYW81MjE_size_16_color_FFFFFF_t_70 4]: /images/20221023/9d9e4196473e4300a72d83d1b9ad5a6d.png