前言
Swagger2(基于openApi3)已经在17年停止维护了,取而代之的是 sagger3(基于openApi3),而国内几乎没有 sagger3使用的文档,百度搜出来的大部分都是swagger2的使用,这篇文章将介绍如何在 java 中使用 openApi3(swagger3)。
一、swagger 3 的使用
Open API
OpenApi是业界真正的 api 文档标准,其是由 Swagger 来维护的,并被linux列为api标准,从而成为行业标准。
Swagger
swagger 是一个 api 文档维护组织,后来成为了 Open API 标准的主要定义者,现在最新的版本为17年发布的 Swagger3(Open Api3)。国内绝大部分人还在用过时的swagger2(17年停止维护并更名为swagger3)swagger2的包名为 io.swagger,而swagger3的包名为 io.swagger.core.v3。
SpringFox
SpringFox是 spring 社区维护的一个项目(非官方),帮助使用者将 swagger2 集成到 Spring 中。常常用于 Spring 中帮助开发者生成文档,并可以轻松的在spring boot中使用。目前已经支持 OpenAPI3 标准。
升级到 OpenAPI3(java 中 swagger1.x 对应 OpenAPI2、swagger 2.x对应OpenAPI3)官方文档
3.0 相关特性
- 支持 Spring 5,Webflux(仅请求映射支持,尚不支持功能端点)、Spring Integration
- 补充官方在 spring boot 的自动装配 pringfox-boot-starter 以后可以直接依赖一个 dependency
- 与2.0更好的规范兼容性
- 支持OpenApi 3.0.3
- 轻依赖 spring-plugin,swagger-core
- 现有的swagger2批注将继续有效并丰富开放式API 3.0规范
常用注解说明
@Api:用在请求的类上,表示对类的说明tags: 说明该类的作用,可以在UI界面上看到的注解value: 该参数没什么意义,在UI界面上也看到,所以不需要配置@ApiOperation:用在请求的方法上,说明方法的用途、作用value: 说明方法的用途、作用notes: 方法的备注说明@ApiImplicitParams:用在请求的方法上,表示一组参数说明@ApiImplicitParam:用在@ApiImplicitParams注解中,指定一个请求参数的各个方面name:参数名value:参数的汉字说明、解释required:参数是否必须传paramType:参数放在哪个地方· header --> 请求参数的获取:@RequestHeader· query --> 请求参数的获取:@RequestParam· path(用于restful接口)--> 请求参数的获取:@PathVariable· body(不常用)· form(不常用)dataType:参数类型,默认String,其它值dataType="Integer" defaultValue:参数的默认值@ApiResponses:用在请求的方法上,表示一组响应@ApiResponse:用在@ApiResponses中,一般用于表达一个错误的响应信息code:数字,例如400message:信息,例如"请求参数没填好"response:抛出异常的类@ApiModel:用于响应类上,表示一个返回响应数据的信息,一般用在post创建的时候,使用@RequestBody这样的场景,请求参数无法使用@ApiImplicitParam注解进行描述的时候)@ApiModelProperty:用在属性上,描述响应类的属性name:属性名value:属性的汉字说明、解释@ApiParam 用于 Controller 中方法的参数说明,放在方法签名当中value:参数说明required:是否必填@ApiIgnore:使用该注解忽略这个API
二、在项目中的使用
- 1、引入pom包,这里同时引入增强包knife4j
<!-- Swagger3 -->
<dependency><groupId>io.springfox</groupId><artifactId>springfox-boot-starter</artifactId><version>3.0.0</version>
</dependency><!-- https://mvnrepository.com/artifact/io.springfox/springfox-swagger-ui -->
<dependency><groupId>io.springfox</groupId><artifactId>springfox-swagger-ui</artifactId><version>3.0.0</version>
</dependency><!-- https://mvnrepository.com/artifact/com.github.xiaoymin/knife4j-spring-boot-starter -->
<dependency><groupId>com.github.xiaoymin</groupId><artifactId>knife4j-spring-boot-starter</artifactId><version>3.0.3</version>
</dependency>
- 2、application.yml 添加配置,放在spring目录下面:
Springfox使用的路径匹配是基于AntPathMatcher的,而Spring Boot 2.6.X使用的是PathPatternMatcher。
# ========================================================================
# 启动报错需要修改以下mvc配置 Failed to start bean 'documentationPluginsBootstrapper'
spring:mvc:pathmatch:matching-strategy: ant_path_matcher
# ========================================================================
- 3、升级spring boot到2.7.0,使用swagger 3.0报错
升级spring boot到2.7.0,项目启动报错,项目使用swagger 3.0 ,具体版本是knife4j-spring-boot-starter的3.0.3,查找解决方案,都说修改配置文件(但是修改配置后仍然无效)或者新增配置类,过滤空情况,但是仍然还是解决了很长时间。报错信息:Caused by: java.lang.NullPointerException: Cannot invoke “org.springframework.web.servlet.mvc.condition.PatternsRequestCondition.getPatterns()” because “this.condition” is null
Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2022-06-04 12:30:54.079 [main] ERROR org.springframework.boot.SpringApplication - Application run failed
org.springframework.context.ApplicationContextException: Failed to start bean 'documentationPluginsBootstrapper'; nested exception is java.lang.NullPointerException: Cannot invoke "org.springframework.web.servlet.mvc.condition.PatternsRequestCondition.getPatterns()" because "this.condition" is nullat org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:181)at org.springframework.context.support.DefaultLifecycleProcessor.access$200(DefaultLifecycleProcessor.java:54)at org.springframework.context.support.DefaultLifecycleProcessor$LifecycleGroup.start(DefaultLifecycleProcessor.java:356)at java.base/java.lang.Iterable.forEach(Iterable.java:75)at org.springframework.context.support.DefaultLifecycleProcessor.startBeans(DefaultLifecycleProcessor.java:155)at org.springframework.context.support.DefaultLifecycleProcessor.onRefresh(DefaultLifecycleProcessor.java:123)at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:935)at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:586)at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:147)at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:734)at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:408)at org.springframework.boot.SpringApplication.run(SpringApplication.java:308)at org.springframework.boot.SpringApplication.run(SpringApplication.java:1306)at org.springframework.boot.SpringApplication.run(SpringApplication.java:1295)at com.cloud.user.UserApplication.main(UserApplication.java:41)
Caused by: java.lang.NullPointerException: Cannot invoke "org.springframework.web.servlet.mvc.condition.PatternsRequestCondition.getPatterns()" because "this.condition" is nullat springfox.documentation.spring.web.WebMvcPatternsRequestConditionWrapper.getPatterns(WebMvcPatternsRequestConditionWrapper.java:56)at springfox.documentation.RequestHandler.sortedPaths(RequestHandler.java:113)at springfox.documentation.spi.service.contexts.Orderings.lambda$byPatternsCondition$3(Orderings.java:89)at java.base/java.util.Comparator.lambda$comparing$77a9974f$1(Comparator.java:473)at java.base/java.util.TimSort.countRunAndMakeAscending(TimSort.java:355)at java.base/java.util.TimSort.sort(TimSort.java:234)at java.base/java.util.Arrays.sort(Arrays.java:1307)at java.base/java.util.ArrayList.sort(ArrayList.java:1721)at java.base/java.util.stream.SortedOps$RefSortingSink.end(SortedOps.java:392)at java.base/java.util.stream.Sink$ChainedReference.end(Sink.java:258)at java.base/java.util.stream.Sink$ChainedReference.end(Sink.java:258)at java.base/java.util.stream.Sink$ChainedReference.end(Sink.java:258)at java.base/java.util.stream.Sink$ChainedReference.end(Sink.java:258)at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:510)at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)at java.base/java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:921)at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)at java.base/java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:682)at springfox.documentation.spring.web.plugins.WebMvcRequestHandlerProvider.requestHandlers(WebMvcRequestHandlerProvider.java:81)at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1625)at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)at java.base/java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:921)at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)at java.base/java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:682)at springfox.documentation.spring.web.plugins.AbstractDocumentationPluginsBootstrapper.withDefaults(AbstractDocumentationPluginsBootstrapper.java:107)at springfox.documentation.spring.web.plugins.AbstractDocumentationPluginsBootstrapper.buildContext(AbstractDocumentationPluginsBootstrapper.java:91)at springfox.documentation.spring.web.plugins.AbstractDocumentationPluginsBootstrapper.bootstrapDocumentationPlugins(AbstractDocumentationPluginsBootstrapper.java:82)at springfox.documentation.spring.web.plugins.DocumentationPluginsBootstrapper.start(DocumentationPluginsBootstrapper.java:100)at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:178)... 14 common frames omitted
解决方案
- 新增一个配置类,注意配置类不能放到swagger的配置类下,测试无效。配置Bean可以放在启动类下或者重新新增一个配置Bean,代码如下:
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.util.ReflectionUtils;
import org.springframework.web.servlet.mvc.method.RequestMappingInfoHandlerMapping;
import springfox.documentation.spring.web.plugins.WebFluxRequestHandlerProvider;
import springfox.documentation.spring.web.plugins.WebMvcRequestHandlerProvider;import java.lang.reflect.Field;
import java.util.List;
import java.util.stream.Collectors;@Slf4j
@Configuration
public class BeanPostProcessorConfig {@Beanpublic BeanPostProcessor springfoxHandlerProviderBeanPostProcessor() {return new BeanPostProcessor() {@Overridepublic Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {if (bean instanceof WebMvcRequestHandlerProvider || bean instanceof WebFluxRequestHandlerProvider) {customizeSpringfoxHandlerMappings(getHandlerMappings(bean));}return bean;}private <T extends RequestMappingInfoHandlerMapping> void customizeSpringfoxHandlerMappings(List<T> mappings) {List<T> copy = mappings.stream().filter(mapping -> mapping.getPatternParser() == null).collect(Collectors.toList());mappings.clear();mappings.addAll(copy);}@SuppressWarnings("unchecked")private List<RequestMappingInfoHandlerMapping> getHandlerMappings(Object bean) {try {Field field = ReflectionUtils.findField(bean.getClass(), "handlerMappings");field.setAccessible(true);return (List<RequestMappingInfoHandlerMapping>) field.get(bean);} catch (IllegalArgumentException | IllegalAccessException e) {throw new IllegalStateException(e);}}};}}
- 4、添加自定义配置类:
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.bind.annotation.CookieValue;
import org.springframework.web.context.request.async.DeferredResult;
import com.github.xiaoymin.knife4j.spring.annotations.EnableKnife4j;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import springfox.documentation.builders.ApiInfoBuilder;
import springfox.documentation.builders.PathSelectors;
import springfox.documentation.builders.RequestHandlerSelectors;
import springfox.documentation.oas.annotations.EnableOpenApi;
import springfox.documentation.service.ApiInfo;
import springfox.documentation.service.Contact;
import springfox.documentation.spi.DocumentationType;
import springfox.documentation.spring.web.plugins.Docket;/*** 文档访问地址:http://ip:port/swagger-ui/index.html* 添加Knife4j可以导出导出离线文档,访问地址:http://ip:port/doc.html**/@Configuration
@EnableKnife4j
@EnableOpenApi
@ConditionalOnProperty(value = "spring.profiles.active", havingValue = "dev")
//@Profile({"dev","test"})
public class SwaggerConfiguration {@Beanpublic Docket createRestApis() {return new Docket(DocumentationType.OAS_30).enable(true)//是否启用:注意生产环境需要关闭.groupName("spring-boot-2.7.3").genericModelSubstitutes(DeferredResult.class).useDefaultResponseMessages(false).forCodeGeneration(true).ignoredParameterTypes(CookieValue.class).apiInfo(apiInfo()).select()//以下拦截配置可以三选一,根据需要进行添加.apis(RequestHandlerSelectors.basePackage("com.qi.study.springboot.controller")).apis(RequestHandlerSelectors.withClassAnnotation(Api.class)).apis(RequestHandlerSelectors.withMethodAnnotation(ApiOperation.class)).paths(PathSelectors.any()).build();}private ApiInfo apiInfo() {return new ApiInfoBuilder().title("使用swagger生成的接口文档").description("开发测试")// 服务条款URL.termsOfServiceUrl("https://www.baidu.com/")// 作者信息.contact(new Contact("qihh", "https://www.baidu.com/", "qihh@136.com")).version("0.0.1").build();}}
- 5、添加拦截器配置,放行相关目录
import com.kfang.web.price.manager.interceptor.AuthorizationInterceptor;
import com.kfang.web.price.manager.interceptor.ContextInterceptor;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.env.Environment;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;import javax.annotation.Resource;@Configuration
public class InterceptorConfiguration implements WebMvcConfigurer {@Resourceprivate Environment env;@Resourceprivate AuthorizationInterceptor authorizationInterceptor;@Overridepublic void addInterceptors(InterceptorRegistry registry) {String[] swaggerExcludePathPatterns = {"/doc.html","/swagger**/**","/swagger-resources/**","/webjars/**","/v3/**"};registry.addInterceptor(new ContextInterceptor()).addPathPatterns("/**");if("dev".equals(env.getProperty("spring.profiles.active"))){}else{swaggerExcludePathPatterns = new String[0];}registry.addInterceptor(authorizationInterceptor).excludePathPatterns("/user/logout").excludePathPatterns("/user/login").excludePathPatterns(swaggerExcludePathPatterns).addPathPatterns("/**").order(-1);}}
- 6、测试demo
@Api(tags = "用户",value = "用户")
@RestController
@RequestMapping(value = "/user", produces = {"application/json;charset=UTF-8"})
public class UserController {@ApiOperation("添加")@PostMapping("/add")@ApiResponses({@ApiResponse(message = "添加", code = 200, response = UserVO.class)}) public UserVO add(@RequestBody @Valid UserAddRequest userAddRequest) {// 将数据写到数据库UserVO userVO = new UserVO();BeanUtils.copyProperties(userAddRequest, userVO);userVO.setId(1L);userVO.setCreateTime(LocalDateTime.now());userVO.setUpdateTime(LocalDateTime.now());return userVO;}@ApiOperation("修改")@PostMapping("/edit")@ApiResponses({@ApiResponse(message = "修改", code = 200, response = UserVO.class)}) public UserVO edit(@RequestBody @Valid UserEditRequest userEditRequest) {// 修改数据库的数据UserVO userVO = new UserVO();BeanUtils.copyProperties(userEditRequest, userVO);userVO.setUpdateTime(LocalDateTime.now());return userVO;}@ApiOperation("查找")@GetMapping("/find")@ApiResponses({@ApiResponse(message = "查找", code = 200, response = UserQueryRequest.class)})public List<UserVO> find(UserQueryRequest userQueryRequest) {return new ArrayList<>();}@ApiOperation("删除")@PostMapping("/delete")public void delete(Long id) {// 将数据库数据删除}@PostMapping(value = "/fileUpload")@ApiOperation(value = "文件上传")@ApiResponses({@ApiResponse(message = "文件上传", code = 200, response = AliyunUploadResult.class)})public String uploadFile(@RequestPart("file") MultipartFile file) {AliyunUploadRequest uploadRequest = new AliyunUploadRequest(file);AliyunUploadResult result = aliyunOss.fileUpload(uploadRequest);return successInfo(result);}@PostMapping(value = "/importDataDetail")@ApiOperation(value = "导入Excel源数据明细")@ApiResponses({@ApiResponse(message = "导入Excel源数据明细出参成功", code = 200, response = Boolean.class)})public String importDataDetail(@RequestPart("file") MultipartFile file,@RequestParam("cityId") String cityId) {}
}
三,启动测试
-
1、访问swagger-ui页面:http://localhost:8080/swagger-ui/index.html
-
2、访问knife4j-ui页面:http://localhost:8080/doc.html
knife4j是springfox-swagger的增强UI实现,为Java开发者在使用Swagger的时候,提供了简洁、强大的接口文档体验。引入pom包,并开启@EnableKnife4j注解就可以使用。
- 3、设置安全密码登录配置:
server.port=8081
knife4j.enable=true
knife4j.basic.enable=true
knife4j.basic.username=admin
knife4j.basic.password=admin
knife4j.setting.language=zh-CN
登录界面:
四、@RequestParam和@RequestPart的区别
@RequestPart
- @RequestPart这个注解用在multipart/form-data表单提交请求的方法上。
- 支持的请求方法的方式MultipartFile,属于Spring的MultipartResolver类。这个请求是通过http协议传输的
@RequestParam
- @RequestParam支持’application/json’,也同样支持multipart/form-data请求
区别
当请求方法的请求参数类型不是String 或 MultipartFile / Part时,而是复杂的请求域时,@RequestParam 依赖Converter or PropertyEditor进行数据解析, RequestPart参考 ‘Content-Type’ header,依赖HttpMessageConverters 进行数据解析
当请求为multipart/form-data时,@RequestParam只能接收String类型的name-value值,@RequestPart可以接收复杂的请求域(像json、xml);@RequestParam 依赖Converter or PropertyEditor进行数据解析, @RequestPart参考'Content-Type' header,依赖HttpMessageConverters进行数据解析
前台请求:
jsonData为Person对象的json字符串
uploadFile为上传的图片
后台接收:
- 1、@RequestPart可以将jsonData的json数据转换为Person对象
@RequestMapping("jsonDataAndUploadFile")
@ResponseBody
public String jsonDataAndUploadFile(@RequestPart("uploadFile") MultiPartFile uploadFile,@RequestPart("jsonData") Person person) {StringBuilder sb = new StringBuilder();sb.append(uploadFile.getOriginalFilename()).append(";;;"));return person.toString() + ":::" + sb.toString();
}
- 2、@RequestParam对于jsonData的json数据只能用String字符串来接收
@RequestMapping("jsonDataAndUploadFile")
@ResponseBody
public String jsonDataAndUploadFile(@RequestPart("uploadFile") MultiPartFile uploadFile,@RequestParam("josnData") String jsonData) {StringBuilder sb = new StringBuilder();sb.append(uploadFile.getOriginalFilename()).append(";;;"));return person.toString() + ":::" + sb.toString();
}