Swashbuckle.Blue

Changed some things the current Swashbuckle/Swagger projects

• Left sidebar navigation
• Upgraded the .net version from 4.0 to 4.5.1
• Added better presentation of your HTTP post payloads and the descriptions of each parameter.
• Utilizing the XML comment from the top of the class model
• Adding parsing for [MaxLength] and [MinLength], before it only read values from [StringLength] attribute
• Customize the logo, header title, and page title
• Night theme for code display
• Added [SwaggerIgnore] attribute to hide properties/controller routes from appearing in documentation
• Added [SwaggerExample] attribute. You can add an example value that will be used as a placeholder in the input fields when the page loads. Example: [SwaggerExample("myValue")], [SwaggerExample("GUID")] generates a new guid for you, [SwaggerExample(RANDOM)] generates a random integer
• Putting API keys in the header now works. In SwaggerConfig.cs set c.ApiKey("apiKey").Name("apiKey").In("header") or "query" for the api key in a query param
• Added code to validate DataAnnotation attribute tags. Use SwashValidator.Validate(inputObject); or SwashValidator.TryValidate(inputObject, out errorMsg);

Seamlessly adds a Swagger to WebApi projects! Combines ApiExplorer and Swagger/swagger-ui to provide a rich discovery, documentation and playground experience to your API consumers.

Once you have a Web API that can describe itself in Swagger, you've opened the treasure chest of Swagger-based tools including a client generator that can be targeted to a wide range of popular platforms. See swagger-codegen for more details.

Things you need to do to have good documentation

• Setting up the XML documentation files
• Create a Swagger Intro
• Adding Data Annotation to your classes
• Using our built in validator to validate your Data Annotations
• Adding SwaggerExample to all your input fields

Swashbuckle Core Features:

• Auto-generated Swagger 2.0
• Seamless integration of swagger-ui
• Reflection-based Schema generation for describing API types
• Out-of-the-box support for leveraging Xml comments
• Support for describing ApiKey, Basic Auth and OAuth2 schemes

Getting Started

There are currently two Nuget packages - the Core library (Swashbuckle.Core) and a convenience package (Swashbuckle) that provides automatic bootstrapping. The latter is only applicable to regular IIS hosted WepApi's. For all other hosting environments, you should only install the Core library and then follow the instructions below to manually enable the Swagger routes.

Once installed and enabled, you should be able to browse the following Swagger docs and UI endpoints respectively:

<your-root-url>/swagger/docs/v1

<your-root-url>/swagger

Generating the XML docs file

Swashbuckle needs to get the commentes from inside your Visual Studio codebase. There is a setting in the properties of your project where it will generate an XML document at compile time. This image shows we are creating the xml file inside of our API project in the folder /XmlDocs

If you have your data contracts in more than one project you need to create an XML documentation file for those too.

Now that we have all of the XML documentation file created we need to tell Swashbuckle that they are located in the /XmlDocs folder.

In the file /ApiProject/App_Start/SwaggerConfig.cs

c.IncludeXmlComments(string.Format(@"{0}\XmlDocs\DataContracts.XML", AppDomain.CurrentDomain.BaseDirectory));
c.IncludeXmlComments(string.Format(@"{0}\XmlDocs\ApiDocs.XML", AppDomain.CurrentDomain.BaseDirectory));

Creating a Good intro

At the top of the Swagger page you can give an intro to your API and tell a little bit about your project to the consumers.

In the /ApiProject/App_Start/SwaggerConfig.cs file you can edit the intro.

c.SingleApiVersion("v3", "The Test API - Documention and Examples")
     .Description("<h1>Welcome to the test API</h1> <p>Thanks for reading our documentation!</p>");

It is recomended to store this introduction text in a HTML file outside of swagger.

var intro = "";
using (var reader = new StreamReader(Assembly.GetExecutingAssembly().GetManifestResourceStream("Api.Content.swaggerIntro.html")))
{
    intro = reader.ReadToEnd();
}
c.SingleApiVersion("v3", "SmartPayments API - Documention and Examples")
    .Description(intro);

Customizing your Payloads

We have created attribute tags to help describe your API payloads in greater detail

[SwaggerExample]

Defines a value to use as the default in your payload. It will default to something basic such as "string" or 0. The goal of [SwaggerExample] is to define your Payloads so well that all the user has to do is click "Try it out" when they load the page. It could take the user minutes filling out proper values for your payloads if you do not define good example data for them to use.

/// <summary>
/// The customers first and last name
/// </summary>
[SwaggerExample("Homer Simpson")]
public string CustomerName { get; set; }

This will put "Homer Simpson" instead of "string" in the CustomerName field.

SwaggerExample also takes in a few strings that will generate values for you

[SwaggerExample("RAND")]

Generates a random int

[SwaggerExample("GUID")]

Generates a random GUID

[SwaggerIgnore]

Hides properties or API routes from being displayed on the page.

/// <summary>
/// The customers first and last name
/// </summary>
[SwaggerIgnore]  //This will hide CustomerName from the user
[SwaggerExample("Homer Simpson")]
public string CustomerName { get; set; }

To hide an API route on the Swagger page

/// <summary>
/// This endpoint is used to register 
/// </summary>
/// <param name="input"></param>
/// <returns></returns>
[HttpPost]
[Route("Register")]
[SwaggerIgnore]  //this will hide the Register endpoint from the Swagger page
[ResponseType(typeof(RegistrationResponse))]
public async Task<IHttpActionResult> Register(RegisterInput input)
{
    return Content(HttpStatusCode.OK, new RegistrationResponse());
}

This is useful if you have an endpoint or property that the client doesn't necessarily need to know about.

SwaggerRouteName

If you want the route name to be displayed differently than how the function name is declared.

/// <summary>
/// This endpoint is used to register 
/// </summary>
/// <param name="input"></param>
/// <returns></returns>
[HttpPost]
[Route("Register")]
[SwaggerIgnore]  //this will hide the Register endpoint from the Swagger page
[ResponseType(typeof(RegistrationResponse))]
public async Task<IHttpActionResult> Register(RegisterInput input)
{
    return Content(HttpStatusCode.OK, new RegistrationResponse());
}

It will now display this route name as Register_User instead of Register

Validation

Swashbuckle.Blue uses a combination of custom and the built in Attribute tags to describe validation rules on your payloads.

Validation Helper

SwagValidator.Validate()

throws an ArgumentException if any of the fields do not pass your defined validation rules

bool SwagValidator.Validate(object input, bool outputJsonPayload = true)

/// <summary>
/// This endpoint is used to register 
/// </summary>
/// <param name="input"></param>
/// <returns></returns>
[HttpPost]
[Route("Register")]
[SwaggerIgnore]  //this will hide the Register endpoint from the Swagger page
[ResponseType(typeof(RegistrationResponse))]
public async Task<IHttpActionResult> Register(RegisterInput input)
{
    SwagValidator.Validate(input);
    return Content(HttpStatusCode.OK, new RegistrationResponse());
}

SwagValidator.TryValidate()

Validates the attribute tag validations declared on the class. Returns false if validation rules are not met and returns the error message in the errorMessage (out) parameter

bool SwagValidator.TryValidate(object input, out string errorMessage, bool outputJsonPayload = true)

/// <summary>
/// This endpoint is used to register 
/// </summary>
/// <param name="input"></param>
/// <returns></returns>
[HttpPost]
[Route("Register")]
[SwaggerIgnore]  //this will hide the Register endpoint from the Swagger page
[ResponseType(typeof(RegistrationResponse))]
public async Task<IHttpActionResult> Register(RegisterInput input)
{
    string errorMsg;
    bool status= SwagValidator.TryValidate(input, errorMsg);
    return Content(HttpStatusCode.OK, new RegistrationResponse());
}

[Required]

Labels the field as required in the UI and will throw an error when you call SwagValidate.Validate(). This will also inform the user in Swagger that this field is Required.

/// <summary>
/// The customers first and last name
/// </summary>
[Required]  //This field is now required
[SwaggerExample("Homer Simpson")]
public string CustomerName { get; set; }

[MaxLength]

The max length a string can contain. This will also inform the user of the MaxLength.

/// <summary>
/// The customers first and last name
/// </summary>
[MaxLength(50)] //CustomerName will have a max length of 50 characters
[SwaggerExample("Homer Simpson")]
public string CustomerName { get; set; }

[MinLength]

The min length a string can contain. This will also inform the user of the MinLength.

/// <summary>
/// The customers first and last name
/// </summary>
[MinLength(5)] //CustomerName will have a min length of 5 characters
[SwaggerExample("Homer Simpson")]
public string CustomerName { get; set; }

[StringLength]

Define a min and max length in one attribute tag. This will also inform the user of the length requirements.

/// <summary>
/// The customers first and last name
/// </summary>
[StringLength(50, MinimumLength = 5)] //CustomerName will have a min length of 5 characters and a max length of 50 characters
[SwaggerExample("Homer Simpson")]
public string CustomerName { get; set; }

[Range]

For numeric types only, define a min and max value

/// <summary>
/// The customers age
/// </summary>
[Range(18,200)] //Age will only allow values between 18 and 200
[SwaggerExample("18")]
public int Age { get; set; }

If your type is a numeric type with a decimal value floats, doubles you should specify decimal values for the min and max.

[Range(18.0,200.0)]

DefinedAttributes

Comes with a list of pre-made validation types

/// <summary>
/// The customers country code
/// </summary>
[DefinedValidation(ValidationType.Country)]  //Forces validation on a proper ISO 3166-1 country code
[SwaggerExample("US")]
public string Country { get; set; }

Other Defined Validation Types

• [DefinedValidation(ValidationType.Country)]
• [DefinedValidation(ValidationType.Currency)]
• [DefinedValidation(ValidationType.Language)]
• [DefinedValidation(ValidationType.Url)]
• [DefinedValidation(ValidationType.Email)]
• [DefinedValidation(ValidationType.IPAddress)]

If none of these defined validations meet your requirements you can use...

RegularExpression attribute

Matches any regular expression to the property

/// <summary>
/// The customers country code
/// </summary>
[RegularExpression(@"^(US|JP)$")]  //Forces the field to only allow US or JP as a country code
[SwaggerExample("US")]
public string Country { get; set; }

Custom Error Messages

You can define a custom error message to display to the user when they fail to meet the requirements

[Required(ErrorMessage = "You should have put a value in here!")]

Installation

IIS Hosted

If your service is hosted in IIS, you can start exposing Swagger docs and a corresponding swagger-ui by simply installing the following Nuget package:

Install-Package Swashbuckle.Blue

This will add a reference to Swashbuckle.Core and also install a bootstrapper (App_Start/SwaggerConfig.cs) that enables the Swagger routes on app start-up using WebActivatorEx.

Self-hosted or OWIN

If your service is self-hosted, just install the Core library:

Install-Package Swashbuckle.Blue.Core

And then manually enable the Swagger docs and optionally, the swagger-ui by invoking the following extension methods (in namespace Swashbuckle.Application) on an instance of HttpConfiguration (e.g. in Program.cs)

httpConfiguration
    .EnableSwagger(c => c.SingleApiVersion("v1", "A title for your API"))
    .EnableSwaggerUi();

Custom Routes

The default route templates for the Swagger docs and swagger-ui are "swagger/docs/{apiVersion}" and "swagger/ui/{*assetPath}" respectively. You're free to change these so long as the provided templates include the relevant route parameters - {apiVersion} and {*assetPath}.

httpConfiguration
    .EnableSwagger("docs/{apiVersion}/swagger", c => c.SingleApiVersion("v1", "A title for your API"))
    .EnableSwaggerUi("sandbox/{*assetPath}");

In this case the URL to swagger-ui will be sandbox/ui/index.

Additional Service Metadata

In addition to operation descriptions, Swagger 2.0 includes several properties to describe the service itself. These can all be provided through the config. interface:

httpConfiguration
    .EnableSwagger(c =>
        {
            c.RootUrl(req => GetRootUrlFromAppConfig());

            c.Schemes(new[] { "http", "https" });

            c.SingleApiVersion("v1", "Swashbuckle.Dummy")
                .Description("A sample API for testing and prototyping Swashbuckle features")
                .TermsOfService("Some terms")
                .Contact(cc => cc
                    .Name("Some contact")
                    .Url("http://tempuri.org/contact")
                    .Email("some.contact@tempuri.org"))
                .License(lc => lc
                    .Name("Some License")
                    .Url("http://tempuri.org/license"));
        });

RootUrl

By default, the service root url is inferred from the request used to access the docs. However, there may be situations (e.g. proxy and load-balanced environments) where this does not resolve correctly. You can workaround this by providing your own code to determine the root URL.

Schemes

If schemes are not explicitly provided in a Swagger 2.0 document, then the scheme used to access the docs is taken as the default. If your API supports multiple schemes and you want to be explicit about them, you can use the Schemes option.

SingleApiVersion

Use this to describe a single version API. Swagger 2.0 includes an "Info" object to hold additional metadata for an API. Version and title are required but you may also provide additional fields as shown above.

NOTE: If you're WebApi is hosted in IIS, you should avoid using full-stops in the version name (e.g. "1.0"). The full-stop at the tail of the URL will cause IIS to treat it as a static file (i.e. with an extension) and bypass the URL Routing Module and therefore, WebApi.

Describing Multiple API Versions

If your API has multiple versions, use MultipleApiVersions instead of SingleApiVersion. In this case, you provide a lambda that tells Swashbuckle which actions should be included in the docs for a given API version. Like SingleApiVersion, Version also returns an "Info" builder so you can provide additional metadata per API version.

httpConfiguration
    .EnableSwagger(c =>
        {
            c.MultipleApiVersions(
                (apiDesc, targetApiVersion) => ResolveVersionSupportByRouteConstraint(apiDesc, targetApiVersion),
                (vc) =>
                {
                    vc.Version("v2", "Swashbuckle Dummy API V2");
                    vc.Version("v1", "Swashbuckle Dummy API V1");
                });
        });
    .EnableSwaggerUi(c =>
        {
            c.EnableDiscoveryUrlSelector();
        });

* You can also enable a select box in the swagger-ui (as shown above) that displays a discovery URL for each version. This provides a convenient way for users to browse documentation for different API versions.

Describing Security/Authorization Schemes

You can use BasicAuth, ApiKey or OAuth2 options to describe security schemes for the API. See https://github.com/swagger-api/swagger-spec/blob/master/versions/2.0.md for more details.

httpConfiguration
    .EnableSwagger(c =>
        {
            //c.BasicAuth("basic")
            //    .Description("Basic HTTP Authentication");

            //c.ApiKey("apiKey")
            //    .Description("API Key Authentication")
            //    .Name("apiKey")
            //    .In("header");

            c.OAuth2("oauth2")
                .Description("OAuth2 Implicit Grant")
                .Flow("implicit")
                .AuthorizationUrl("http://petstore.swagger.wordnik.com/api/oauth/dialog")
                //.TokenUrl("https://tempuri.org/token")
                .Scopes(scopes =>
                {
                    scopes.Add("read", "Read access to protected resources");
                    scopes.Add("write", "Write access to protected resources");
                });

            c.OperationFilter<AssignOAuth2SecurityRequirements>();
        });
    .EnableSwaggerUi(c =>
        {
            c.EnableOAuth2Support("test-client-id", "test-realm", "Swagger UI");
        });

NOTE: These only define the schemes and need to be coupled with a corresponding "security" property at the document or operation level to indicate which schemes are required for each operation. To do this, you'll need to implement a custom IDocumentFilter and/or IOperationFilter to set these properties according to your specific authorization implementation

* If your API supports the OAuth2 Implicit flow, and you've described it correctly, according to the Swagger 2.0 specification, you can enable UI support as shown above.

Customize the Operation Listing

If necessary, you can ignore obsolete actions and provide custom grouping/sorting strategies for the list of Operations in a Swagger document:

httpConfiguration
    .EnableSwagger(c =>
        {
            c.IgnoreObsoleteActions();

            c.GroupActionsBy(apiDesc => apiDesc.HttpMethod.ToString());

            c.OrderActionGroupsBy(new DescendingAlphabeticComparer());
        });

IgnoreObsoleteActions

Set this flag to omit operation descriptions for any actions decorated with the Obsolete attribute

NOTE: If you want to omit specific operations but without using the Obsolete attribute, you can create an IDocumentFilter or make use of the built in ApiExplorerSettingsAttribute

GroupActionsBy

Each operation can be assigned one or more tags which are then used by consumers for various reasons. For example, the swagger-ui groups operations according to the first tag of each operation. By default, this will be controller name but you can use this method to override with any value.

OrderActionGroupsBy

You can also specify a custom sort order for groups (as defined by GroupActionsBy) to dictate the order in which operations are listed. For example, if the default grouping is in place (controller name) and you specify a descending alphabetic sort order, then actions from a ProductsController will be listed before those from a CustomersController. This is typically used to customize the order of groupings in the swagger-ui.

Modifying Generated Schemas

Swashbuckle makes a best attempt at generating Swagger compliant JSON schemas for the various types exposed in your API. However, there may be occasions when more control of the output is needed. This is supported through the following options:

httpConfiguration
    .EnableSwagger(c =>
        {
            c.MapType<ProductType>(() => new Schema { type = "integer", format = "int32" });

            c.SchemaFilter<ApplySchemaVendorExtensions>();
            
            c.IgnoreObsoleteProperties();

            c.UseFullTypeNameInSchemaIds();

            c.DescribeAllEnumsAsStrings();
        });

IgnoreObsoleteProperties

Set this flag to omit schema property descriptions for any type properties decorated with the Obsolete attribute

MapType

Use this option to override the Schema generation for a specific type.

It should be noted that the resulting Schema will be placed "inline" for any applicable Operations. While Swagger 2.0 supports inline definitions for "all" Schema types, the swagger-ui tool does not. It expects "complex" Schemas to be defined separately and referenced. For this reason, you should only use the MapType option when the resulting Schema is a primitive or array type.

If you need to alter a complex Schema, use a Schema filter.

SchemaFilter

If you want to post-modify "complex" Schemas once they've been generated, across the board or for a specific type, you can wire up one or more Schema filters.

ISchemaFilter has the following interface:

void Apply(Schema schema, SchemaRegistry schemaRegistry, Type type);

A typical implementation will inspect the system Type and modify the Schema accordingly. If necessary, the schemaRegistry can be used to obtain or register Schemas for other Types

UseFullTypeNamesInSchemaIds

In a Swagger 2.0 document, complex types are typically declared globally and referenced by unique Schema Id. By default, Swashbuckle does NOT use the full type name in Schema Ids. In most cases, this works well because it prevents the "implementation detail" of type namespaces from leaking into your Swagger docs and UI. However, if you have multiple types in your API with the same class name, you'll need to opt out of this behavior to avoid Schema Id conflicts.

DescribeAllEnumsAsStrings

In accordance with the built in JsonSerializer, Swashbuckle will, by default, describe enums as integers. You can change the serializer behavior by configuring the StringToEnumConverter globally or for a given enum type. Swashbuckle will honor this change out-of-the-box. However, if you use a different approach to serialize enums as strings, you can also force Swashbuckle to describe them as strings.

Modifying Generated Operations

Similar to Schema filters, Swashbuckle also supports Operation and Document filters:

httpConfiguration
    .EnableSwagger(c => c.SingleApiVersion("v1", "A title for your API"))
        {
            c.OperationFilter<AddDefaultResponse>();

            c.DocumentFilter<ApplyDocumentVendorExtensions>();
        });

OperationFilter

Post-modify Operation descriptions once they've been generated by wiring up one or more Operation filters.

IOperationFilter has the following interface:

void Apply(Operation operation, SchemaRegistry schemaRegistry, ApiDescription apiDescription);

A typical implementation will inspect the ApiDescription and modify the Operation accordingly. If necessary, the schemaRegistry can be used to obtain or register Schemas for Types that are used in the Operation.

DocumentFilter

Post-modify the entire Swagger document by wiring up one or more Document filters.

IDocumentFilter has the following interface:

void Apply(SwaggerDocument swaggerDoc, SchemaRegistry schemaRegistry, IApiExplorer apiExplorer);

This gives full control to modify the final SwaggerDocument. You can gain additional context from the provided SwaggerDocument (e.g. version) and IApiExplorer. You should have a good understanding of the Swagger 2.0 spec. before using this option.

Wrapping the SwaggerGenerator with Additional Behavior

The default implementation of ISwaggerProvider, the interface used to obtain Swagger metadata for a given API, is the SwaggerGenerator. If neccessary, you can inject your own implementation or wrap the existing one with additional behavior. For example, you could use this option to inject a "Caching Proxy" that attempts to retrieve the SwaggerDocument from a cache before delegating to the built-in generator:

httpConfiguration
    .EnableSwagger(c => c.SingleApiVersion("v1", "A title for your API"))
        {
			c.CustomProvider((defaultProvider) => new CachingSwaggerProvider(defaultProvider));
        });

Including XML Comments

If you annotate Controllers and API Types with Xml Comments, you can incorporate those comments into the generated docs and UI. The Xml tags are mapped to Swagger properties as follows:

• Action summary -> Operation.summary
• Action remarks -> Operation.description
• Parameter summary -> Parameter.description
• Type summary -> Schema.descripton
• Property summary -> Schema.description (i.e. on a property Schema)

You can enable this by providing the path to one or more XML comments files:

httpConfiguration
    .EnableSwagger(c =>
        {
            c.SingleApiVersion("v1", "A title for your API");
            c.IncludeXmlComments(GetXmlCommentsPathForControllers());
            c.IncludeXmlComments(GetXmlCommentsPathForModels());
        });

NOTE: You will need enable the output of the XML documentation file. This is enabled by going to project properties -> Build -> Output. The "XML documentation file" needs checked and a path assigned such as "bin\Debug\MyProj.XML" you will also want to verify this across each build configuration. Here's an example of reading the file but it may need modified based upon your specific project settings:

httpConfiguration
    .EnableSwagger(c =>
        {
            var baseDirectory = AppDomain.CurrentDomain.BaseDirectory;
            var commentsFileName = Assembly.GetExecutingAssembly().GetName().Name + ".XML";
            var commentsFile = Path.Combine(baseDirectory, commentsFileName);

            c.SingleApiVersion("v1", "A title for your API");
            c.IncludeXmlComments(commentsFile);
            c.IncludeXmlComments(GetXmlCommentsPathForModels());
        });

Response Codes

Swashbuckle will automatically create a "success" response for each operation based on the action's return type. If it's a void, the status code will be 204 (No content), otherwise 200 (Ok). This mirrors WebApi's default behavior. If you need to change this and/or list additional response codes, you can use the non-standard "response" tag:

/// <response code="201">Account created</response>
/// <response code="400">Username already in use</response>
public int Create(Account account)

Working Around Swagger 2.0 Constraints

In contrast to WebApi, Swagger 2.0 does not include the query string component when mapping a URL to an action. As a result, Swashbuckle will raise an exception if it encounters multiple actions with the same path (sans query string) and HTTP method. You can workaround this by providing a custom strategy to pick a winner or merge the descriptions for the purposes of the Swagger docs

httpConfiguration
    .EnableSwagger((c) =>
        {
            c.SingleApiVersion("v1", "A title for your API"));
            c.ResolveConflictingActions(apiDescriptions => apiDescriptions.First());
        });

See the following discusssion for more details:

https://github.com/domaindrivendev/Swashbuckle/issues/142

BooleanValues

The swagger-ui renders boolean data types as a dropdown. By default, it provides "true" and "false" strings as the possible choices. You can use this option to change these to something else, for example 0 and 1.

SetValidatorUrl/DisableValidator

By default, swagger-ui will validate specs against swagger.io's online validator and display the result in a badge at the bottom of the page. Use these options to set a different validator URL or to disable the feature entirely.

DocExpansion

Use this option to control how the Operation listing is displayed. It can be set to "None" (default), "List" (shows operations for each resource), or "Full" (fully expanded: shows operations and their details).

Troubleshooting

Troubleshooting??? I thought this was all supposed to be "seamless"? OK you've called me out! Things shouldn't go wrong, but if they do, take a look at the FAQ's for inspiration.

Customizing the Generated Swagger Docs

The following snippet demonstrates the minimum configuration required to get the Swagger docs and swagger-ui up and running:

httpConfiguration
    .EnableSwagger(c => c.SingleApiVersion("v1", "A title for your API"))
    .EnableSwaggerUi();

These methods expose a range of configuration and extensibility options that you can pick and choose from, combining the convenience of sensible defaults with the flexibility to customize where you see fit. Read on to learn more.

Troubleshooting and FAQ's

1. Swagger-ui showing "Can't read swagger JSON from ..."
2. Page not found when accessing the UI
3. Swagger-ui broken by Visual Studio 2013
4. OWIN Hosted in IIS - Incorrect VirtualPathRoot Handling
5. How to add vendor extensions

Swagger-ui showing "Can't read swagger JSON from ..."

If you see this message, it means the swagger-ui received an unexpected response when requesting the Swagger document. You can troubleshoot further by navigating directly to the discovery URL included in the error message. This should provide more details.

If the discovery URL returns a 404 Not Found response, it may be due to a full-stop in the version name (e.g. "1.0"). This will cause IIS to treat it as a static file (i.e. with an extension) and bypass the URL Routing Module and therefore, WebApi.

To workaround, you can update the version name specified in SwaggerConfig.cs. For example, to "v1", "1-0" etc. Alternatively, you can change the route template being used for the swagger docs (as shown here) so that the version parameter is not at the end of the route.

Page not found when accessing the UI

Swashbuckle serves an embedded version of the swagger-ui through the WebApi pipeline. But, most of the URL's contain extensions (.html, .js, .css) and many IIS environments are configured to bypass the managed pipeline for paths containing extensions.

In previous versions of Swashbuckle, this was resolved by adding the following setting to your Web.config:

<system.webServer>
  <modules runAllManagedModulesForAllRequests="true">
</modules>

This is no longer neccessary in Swashbuckle 5.0 because it serves the swagger-ui through extensionless URL's.

However, if you're using the SingleApiVersion, MultipleApiVersions or CustomAsset config. settings you could still get this error. Check to ensure you're not specifying a value that causes a URL with extension to be referenced in the UI. For example a full-stop in a version number ...

httpConfiguration
    .EnableSwagger(c => c.SingleApiVersion("1.0", "A title for your API"))
    .EnableSwaggerUi();

Will result in a discovery URL like this "/swagger/docs/1.0" where the full-stop is treated as a file extension.

Swagger-ui broken by Visual Studio 2013

VS 2013 ships with a new feature - Browser Link that improves the web development workflow by setting up a channel between the IDE and pages being previewed in a local browser. It does this by dynamically injecting JavaScript into your files.

Although this JavaScript SHOULD have no affect on your production code, it appears to be breaking the swagger-ui.

I hope to find a permanent fix but in the meantime, you'll need to workaround this isuse by disabling the feature in your web.config:

<appSettings>
    <add key="vs:EnableBrowserLink" value="false"/>
</appSettings>< appSettings>

OWIN Hosted in IIS - Incorrect VirtualPathRoot Handling

When you host WebApi 2 on top of OWIN/SystemWeb, Swashbuckle cannot correctly resolve VirtualPathRoot by default.

You must either explicitly set VirtualPathRoot in your HttpConfiguration at startup, or perform customization like this to fix automatic discovery:

SwaggerSpecConfig.Customize(c =>
{
    c.ResolveBasePathUsing(req =>
        req.RequestUri.GetLeftPart(UriPartial.Authority) +
        req.GetRequestContext().VirtualPathRoot.TrimEnd('/'));
}

How to add vendor extensions

Swagger 2.0 allows additional meta-data (aka vendor extensions) to be added at various points in the Swagger document. Swashbuckle supports this by including a "vendorExtensions" dictionary with each of the extensible Swagger types. Meta-data can be added to these dictionaries from custom Schema, Operation or Document filters. For example:

public class ApplySchemaVendorExtensions : ISchemaFilter
{
    public void Apply(Schema schema, SchemaRegistry schemaRegistry, Type type)
    {
        schema.vendorExtensions.Add("x-foo", "bar");
    }
}

As per the specification, all extension properties should be prefixed by "x-"