初衷

记得以前写接口，写完后会整理一份API接口文档，而文档的格式如果没有具体要求的话，最终展示的文档则完全决定于开发者的心情。也许多点，也许少点。甚至，接口总是需要适应新需求的，修改了，增加了，这份文档维护起来就很困难了。于是发现了swagger，自动生成文档的工具。

swagger介绍

首先，官网这样写的：

Swagger – The World's Most Popular Framework for APIs.

因为自强所以自信。swagger官方更新很给力，各种版本的更新都有。swagger会扫描配置的API文档格式自动生成一份json数据，而swagger官方也提供了ui来做通常的展示，当然也支持自定义ui的。不过对后端开发者来说，能用就可以了，官方就可以了。

最强的是，不仅展示API，而且可以调用访问，只要输入参数既可以try it out.

效果为先，最终展示doc界面，也可以设置为中文：

image

在dropwizard中使用

详细信息见另一篇在dropwizard中使用Swagger

在spring-boot中使用

以前总是看各种博客来配置，这次也不例外。百度了千篇一律却又各有细微的差别，甚至时间上、版本上各有不同。最终还是去看官方文档，终于发现了官方的sample。针对于各种option的操作完全在demo中了，所以clone照抄就可以用了。

github sample源码

配置

1.需要依赖三个包：

        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-swagger2</artifactId>
            <version>${springfox-version}</version>
        </dependency>
        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-swagger-ui</artifactId>
            <version>${springfox-version}</version>
        </dependency>
         <dependency>
            <groupId>io.swagger</groupId>
            <artifactId>swagger-core</artifactId>
            <version>${springfox-version}</version>
        </dependency>

第一个是API获取的包，第二是官方给出的一个ui界面。这个界面可以自定义，默认是官方的，第三个是注释包，对于安全问题，以及ui路由设置需要着重思考。

2.swagger的configuration

需要特别注意的是swagger scan base package,这是扫描注解的配置，即你的API接口位置。

@Configuration
@EnableSwagger2
public class SwaggerConfig {

    public static final String SWAGGER_SCAN_BASE_PACKAGE = "com.test.web.controllers";
    public static final String VERSION = "1.0.0";

    ApiInfo apiInfo() {
        return new ApiInfoBuilder()
                .title("Swagger API")
                .description("This is to show api description")
                .license("Apache 2.0")
                .licenseUrl("http://www.apache.org/licenses/LICENSE-2.0.html")
                .termsOfServiceUrl("")
                .version(VERSION)
                .contact(new Contact("","", "miaorf@outlook.com"))
                .build();
    }

    @Bean
    public Docket customImplementation(){
        return new Docket(DocumentationType.SWAGGER_2)
                .select()
                .apis(RequestHandlerSelectors.basePackage(SWAGGER_SCAN_BASE_PACKAGE))
                .build()
                .directModelSubstitute(org.joda.time.LocalDate.class, java.sql.Date.class)
                .directModelSubstitute(org.joda.time.DateTime.class, java.util.Date.class)
                .apiInfo(apiInfo());
    }
}

当然，scan package 也可以换成别的条件，比如：

    @Bean
    public Docket api() {
        return new Docket(DocumentationType.SWAGGER_2)
                .apiInfo(apiInfo())
                .select()
                .apis(RequestHandlerSelectors.withMethodAnnotation(ApiOperation.class))
                .build();
    }

3.在API上做一些声明

//本controller的功能描述
@Api(value = "pet", description = "the pet API")
public interface PetApi {

    //option的value的内容是这个method的描述，notes是详细描述，response是最终返回的json model。其他可以忽略
    @ApiOperation(value = "Add a new pet to the store", notes = "", response = Void.class, authorizations = {
        @Authorization(value = "petstore_auth", scopes = {
            @AuthorizationScope(scope = "write:pets", description = "modify pets in your account"),
            @AuthorizationScope(scope = "read:pets", description = "read your pets")
            })
    }, tags={ "pet", })

    //这里是显示你可能返回的http状态，以及原因。比如404 not found, 303 see other
    @ApiResponses(value = { 
        @ApiResponse(code = 405, message = "Invalid input", response = Void.class) })
    @RequestMapping(value = "/pet",
        produces = { "application/xml", "application/json" }, 
        consumes = { "application/json", "application/xml" },
        method = RequestMethod.POST)
    ResponseEntity<Void> addPet(
    //这里是针对每个参数的描述
    @ApiParam(value = "Pet object that needs to be added to the store" ,required=true ) @RequestBody Pet body);

案例：

package com.test.mybatis.web.controllers;

import com.test.mybatis.domain.entity.City;
import com.test.mybatis.domain.entity.Hotel;
import com.test.mybatis.domain.mapper.CityMapper;
import com.test.mybatis.domain.mapper.HotelMapper;
import com.test.mybatis.domain.model.common.BaseResponse;
import io.swagger.annotations.*;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;

import java.util.List;

/**
 * Created by miaorf on 2016/9/10.
 */

@Api(value = "Test", description = "test the swagger API")
@RestController
public class TestController {

    @Autowired
    private CityMapper cityMapper;
    @Autowired
    private HotelMapper hotelMapper;

    @ApiOperation(value = "get city by state", notes = "Get city by state", response = City.class)
    @ApiResponses(value = {@ApiResponse(code = 405, message = "Invalid input", response = City.class) })
    @RequestMapping(value = "/city", method = RequestMethod.GET)
    public ResponseEntity<BaseResponse<City>>  getCityByState(
            @ApiParam(value = "The id of the city" ,required=true ) @RequestParam String state){

        City city = cityMapper.findByState(state);
        if (city!=null){
            BaseResponse response = new BaseResponse(city,true,null);
            return new ResponseEntity<>(response, HttpStatus.OK);
        }
        return new ResponseEntity<>(HttpStatus.INTERNAL_SERVER_ERROR);
    }

    @ApiOperation(value = "save city", notes = "", response = City.class)
    @RequestMapping(value = "/city", method = RequestMethod.POST)
    public ResponseEntity<BaseResponse<City>> saveCity(
            @ApiParam(value = "The id of the city" ,required=true ) @RequestBody City city){

        int save = cityMapper.save(city);
        if (save>0){
            BaseResponse response = new BaseResponse(city,true,null);
            return new ResponseEntity<>(response, HttpStatus.OK);
        }
        return new ResponseEntity<>(HttpStatus.INTERNAL_SERVER_ERROR);
    }

    @ApiOperation(value = "save hotel", notes = "", response = Hotel.class)
    @RequestMapping(value = "/hotel", method = RequestMethod.POST)
    public ResponseEntity<BaseResponse<Hotel>> saveHotel(
            @ApiParam(value = "hotel" ,required=true ) @RequestBody Hotel hotel){

        int save = hotelMapper.save(hotel);
        if (save>0){
            BaseResponse response = new BaseResponse(hotel,true,null);
            return new ResponseEntity<>(response, HttpStatus.OK);
        }
        return new ResponseEntity<>(HttpStatus.INTERNAL_SERVER_ERROR);
    }

    @ApiOperation(value = "get the hotel", notes = "get the hotel by the city id", response = Hotel.class)
    @RequestMapping(value = "/hotel", method = RequestMethod.GET)
    public ResponseEntity<BaseResponse<Hotel>> getHotel(
            @ApiParam(value = "the hotel id" ,required=true ) @RequestParam Long cid){

        List<Hotel> hotels = hotelMapper.selectByCityId(cid);
        return new ResponseEntity<>(new BaseResponse(hotels,true,null), HttpStatus.OK);
    }

    @ApiOperation(value = "update the hotel", notes = "update the hotel", response = Hotel.class)
    @RequestMapping(value = "/hotel", method = RequestMethod.PUT)
    public ResponseEntity<BaseResponse<Hotel>> updateHotel(
            @ApiParam(value = "the hotel" ,required=true ) @RequestBody Hotel hotel){

        int result = hotelMapper.update(hotel);
        return new ResponseEntity<>(new BaseResponse(result,true,null), HttpStatus.OK);
    }

    @ApiOperation(value = "delete the  hotel", notes = "delete the hotel by the hotel id", response = City.class)
    @RequestMapping(value = "/hotel", method = RequestMethod.DELETE)
    public ResponseEntity<BaseResponse<Hotel>> deleteHotel(
            @ApiParam(value = "the hotel id" ,required=true ) @RequestParam Long htid){

        int result = hotelMapper.delete(htid);
        return new ResponseEntity<>(new BaseResponse(result,true,null), HttpStatus.OK);
    }

}

4.设定访问API doc的路由

在配置文件中，application.yml中声明：

springfox.documentation.swagger.v2.path: /api-docs

这个path就是json的访问request mapping.可以自定义，防止与自身代码冲突。

API doc的显示路由是：http://localhost:8080/swagger-ui.html

如果项目是一个webservice，通常设定home / 指向这里：

@Controller
public class HomeController {

    @RequestMapping(value = "/swagger")
    public String index() {
        System.out.println("swagger-ui.html");
        return "redirect:swagger-ui.html";
    }
}

5.访问

就是上面的了。但是，注意到安全问题就会感觉困扰。首先，该接口请求有几个：

http://localhost:8080/swagger-resources/configuration/ui
http://localhost:8080/swagger-resources
http://localhost:8080/api-docs
http://localhost:8080/swagger-resources/configuration/security

除却自定义的url，还有2个ui显示的API和一个安全问题的API。关于安全问题的配置还没去研究，但目前发现一个问题是在我的一个项目中，所有的url必须带有query htid=xxx,这是为了sso portal验证的时候需要。这样这个几个路由就不符合要求了。