ASP.NET WebApi使用Swagger做接口文档

一，什么是Swagger

相信在做接口的,都会被接口文档烦的不行，接口文档没及时更新，前后端不一致等问题，而Swagger就是用来解决这一问题的！Swagger会根据api方法的注释生成相应的文档，让开发人员不必须再去写接口文档！效果图如下

二，如何在ASP.NET WebApi中使用Swagger

首先，创建一个WebApi 程序SwaggerDemo,这里我不再说如何创建WebApi了，相信大部分的朋友都会，不会的，稍加研究一下就会了。

然后，从nuget 管理器上面下载Swagger,搜索Swagger,选择Swashbuckle安装。

安装完成后，我们新创建一个控制器，因为本人懒，就这样直接命名为Default了，

添加相应的接口方法和注释，我们的基本工作就算完成了。

 /// <summary>
        /// hello
        /// </summary>
        /// <returns></returns>
        [HttpGet]
        public string Hello()
        {
            return "hello ,to go!";
        }

        /// <summary>
        /// 返回输入值
        /// </summary>
        /// <param name="str">str</param>
        /// <returns></returns>
        public string GetMess(string str)
        {
            return "GET:" + str;
        }
        /// <summary>
        /// 返回空
        /// </summary>
        /// <returns></returns>
        [HttpGet]
        public string BackNull()
        {
            return null;
        }

三，Swagger相关的配置设置

要想Swagger能正常运行起来，我们还要进行一些配置

1.设置xml生成文档，在项目的属性--生成--输出 选中xml文档文件;

2.添加相关的操作类 SwaggerCacheProvider

    public class SwaggerCacheProvider: ISwaggerProvider
    {
        private readonly ISwaggerProvider _swaggerProvider;
        private static ConcurrentDictionary<string, SwaggerDocument> _cache = new ConcurrentDictionary<string, SwaggerDocument>();
        private readonly string _xml;
        /// <summary>
        /// 
        /// </summary>
        /// <param name="swaggerProvider"></param>
        /// <param name="xml">xml文档路径</param>
        public SwaggerCacheProvider(ISwaggerProvider swaggerProvider, string xml)
        {
            _swaggerProvider = swaggerProvider;
            _xml = xml;
        }

        public SwaggerDocument GetSwagger(string rootUrl, string apiVersion)
        {

            var cacheKey = string.Format("{0}_{1}", rootUrl, apiVersion);
            SwaggerDocument srcDoc = null;
            //只读取一次
            if (!_cache.TryGetValue(cacheKey, out srcDoc))
            {
                srcDoc = _swaggerProvider.GetSwagger(rootUrl, apiVersion);

                srcDoc.vendorExtensions = new Dictionary<string, object> { { "ControllerDesc", GetControllerDesc() } };
                _cache.TryAdd(cacheKey, srcDoc);
            }
            return srcDoc;
        }

        /// <summary>
        /// 从API文档中读取控制器描述
        /// </summary>
        /// <returns>所有控制器描述</returns>
        public ConcurrentDictionary<string, string> GetControllerDesc()
        {
            string xmlpath = _xml;
            ConcurrentDictionary<string, string> controllerDescDict = new ConcurrentDictionary<string, string>();
            if (File.Exists(xmlpath))
            {
                XmlDocument xmldoc = new XmlDocument();
                xmldoc.Load(xmlpath);
                string type = string.Empty, path = string.Empty, controllerName = string.Empty;

                string[] arrPath;
                int length = -1, cCount = "Controller".Length;
                XmlNode summaryNode = null;
                foreach (XmlNode node in xmldoc.SelectNodes("//member"))
                {
                    type = node.Attributes["name"].Value;
                    if (type.StartsWith("T:"))
                    {
                        //控制器
                        arrPath = type.Split('.');
                        length = arrPath.Length;
                        controllerName = arrPath[length - 1];
                        if (controllerName.EndsWith("Controller"))
                        {
                            //获取控制器注释
                            summaryNode = node.SelectSingleNode("summary");
                            string key = controllerName.Remove(controllerName.Length - cCount, cCount);
                            if (summaryNode != null && !string.IsNullOrEmpty(summaryNode.InnerText) && !controllerDescDict.ContainsKey(key))
                            {
                                controllerDescDict.TryAdd(key, summaryNode.InnerText.Trim());
                            }
                        }
                    }
                }
            }
            return controllerDescDict;
        }
    }

3.添加js汉化文件swagger.js，并属性设置为嵌入式资源

'use strict';
window.SwaggerTranslator = {
    _words: [],

    translate: function () {
        var $this = this;
        $('[data-sw-translate]').each(function () {
            $(this).html($this._tryTranslate($(this).html()));
            $(this).val($this._tryTranslate($(this).val()));
            $(this).attr('title', $this._tryTranslate($(this).attr('title')));
        });
    },

    setControllerSummary: function () {

        try {
            console.log($("#input_baseUrl").val());
            $.ajax({
                type: "get",
                async: true,
                url: $("#input_baseUrl").val(),
                dataType: "json",
                success: function (data) {

                    var summaryDict = data.ControllerDesc;
                    console.log(summaryDict);
                    var id, controllerName, strSummary;
                    $("#resources_container .resource").each(function (i, item) {
                        id = $(item).attr("id");
                        if (id) {
                            controllerName = id.substring(9);
                            try {
                                strSummary = summaryDict[controllerName];
                                if (strSummary) {
                                    $(item).children(".heading").children(".options").first().prepend('<li class="controller-summary" style="color:green;" title="' + strSummary + '">' + strSummary + '</li>');
                                }
                            } catch (e) {
                                console.log(e);
                            }
                        }
                    });
                }
            });
        } catch (e) {
            console.log(e);
        }
    },
    _tryTranslate: function (word) {
        return this._words[$.trim(word)] !== undefined ? this._words[$.trim(word)] : word;
    },

    learn: function (wordsMap) {
        this._words = wordsMap;
    }
};


/* jshint quotmark: double */
window.SwaggerTranslator.learn({
    "Warning: Deprecated": "警告：已过时",
    "Implementation Notes": "实现备注",
    "Response Class": "响应类",
    "Status": "状态",
    "Parameters": "参数",
    "Parameter": "参数",
    "Value": "值",
    "Description": "描述",
    "Parameter Type": "参数类型",
    "Data Type": "数据类型",
    "Response Messages": "响应消息",
    "HTTP Status Code": "HTTP状态码",
    "Reason": "原因",
    "Response Model": "响应模型",
    "Request URL": "请求URL",
    "Response Body": "响应体",
    "Response Code": "响应码",
    "Response Headers": "响应头",
    "Hide Response": "隐藏响应",
    "Headers": "头",
    "Try it out!": "试一下！",
    "Show/Hide": "显示/隐藏",
    "List Operations": "显示操作",
    "Expand Operations": "展开操作",
    "Raw": "原始",
    "can't parse JSON.  Raw result": "无法解析JSON. 原始结果",
    "Model Schema": "模型架构",
    "Model": "模型",
    "apply": "应用",
    "Username": "用户名",
    "Password": "密码",
    "Terms of service": "服务条款",
    "Created by": "创建者",
    "See more at": "查看更多：",
    "Contact the developer": "联系开发者",
    "api version": "api版本",
    "Response Content Type": "响应Content Type",
    "fetching resource": "正在获取资源",
    "fetching resource list": "正在获取资源列表",
    "Explore": "浏览",
    "Show Swagger Petstore Example Apis": "显示 Swagger Petstore 示例 Apis",
    "Can't read from server.  It may not have the appropriate access-control-origin settings.": "无法从服务器读取。可能没有正确设置access-control-origin。",
    "Please specify the protocol for": "请指定协议：",
    "Can't read swagger JSON from": "无法读取swagger JSON于",
    "Finished Loading Resource Information. Rendering Swagger UI": "已加载资源信息。正在渲染Swagger UI",
    "Unable to read api": "无法读取api",
    "from path": "从路径",
    "server returned": "服务器返回"
});
$(function () {
    window.SwaggerTranslator.translate();
    window.SwaggerTranslator.setControllerSummary();
});

 4.配置Swagger

在从nuget中下载Swagger的时候，会自动在App_Start中生成SwaggerConfig.cs 文件，这是Swagger的配置文件，我们在文件中添加如下代码

 在EnableSwagger中添加

   c.IncludeXmlComments(string.Format("{0}/bin/SwaggerDemo.XML", System.AppDomain.CurrentDomain.BaseDirectory));
                        c.CustomProvider((defaultProvider) => new SwaggerCacheProvider(defaultProvider, string.Format("{0}/bin/SwaggerDemo.XML", System.AppDomain.CurrentDomain.BaseDirectory)));

其中，xml文件为项目生成的文件。

在EnableSwaggerUi中添加

c.InjectJavaScript(System.Reflection.Assembly.GetExecutingAssembly(), "SwaggerDemo.swagger.js");

其中，js文件为我们刚刚添加的js汉化文件

四，浏览效果 

我们启动项目，打开浏览器，输入地址  http://IP:端口号/swagger  即可看到如第一张图的效果了！

异常解决方法

Swagger Not supported by Swagger 2.0: Multiple operations with path 解决方法

一个controller中只能有一个HttpGet请求，多了就会报错。建议减少重载方法，将其他Get方法分开

如果在swagger.config中加上c.ResolveConflictingActions(apiDescriptions => apiDescriptions.First());则会只显示第一个get方法

加了上面的方法后,get可能会只显示一条记录

RouteConfig文件

  routes.MapRoute(
                name: "Default",
                url: "{controller}/{action}/{id}",
                defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
            );

public static void RegisterRoutes(RouteCollection routes)
        {
            routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
            RouteTable.Routes.MapHttpRoute(
               name: "SwaggerApi",
               routeTemplate: "api/docs/{controller}/{action}",
               defaults: new { swagger = true }
           );
            routes.MapRoute(
                name: "Default",
                url: "{controller}/{action}/{id}",
                defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
            );
        }

其他异常

一直显示这个界面

只返回Json Result的content negotiation代替Web Api中默认的content negotiation造成的.

WebApiConfig

config.Services.Replace(typeof(IContentNegotiator), new JsonContentNegotiator(jsonFormatter));