Open API(Swagger) and Swagger UI on Azure Functions v2(C#)

I will explain an easy way to provide Open API and Swagger UI in Azure Functions v2.

  1. You install AzureFunctions.Extensions.Swashbuckle package with nuget.
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install nuget package

2. You add startup code on your functions project.

3. You add Open API function and Swagger UI function.

You start DEBUG and access http://localhost:7071/api/swagger/ui on your browser.

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swagger ui

Please add this API code to the project to try it out.

And start DEBUG and access swagger ui.

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Next, The following describes the available Attributes.


If you want to set API result per Http Status, you use to ProducesResponseTypeAttribute.

ProducesResponseTypeAttirbute can multiple set.

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If you want to set RequestBody, you use to RequestBodyTypeAttribute.

RequestBodyTypeAttribute must set in HttpRequest or HttpRequestMessage paramater.

RequestModelClass’s property can set data annotation.

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If you want to set Http header, you use to RequestHttpHeaderAttribute.

RequestHttpHeaderAttribute can set multiple, and RequestHttpHeaderAttribute can set Class or Method.

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This package collect all HttpTrigger functions and add in Open API.

If you have Http Trigger Functions that you do not want to add to Open Api, use SwaggerIgnoreAttribute.

Finally, I will introduce how to import XmlCommentDocument and add it to Open API.

If you want to add XML comments in the program code to the OpenAPI Description, do the next:

  1. Add this xml in to functions project’s csproj file.
<PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">

2. Change host.json. You add extensions setting.

"version": "2.0",
"extensions": {
"Swashbuckle": {
"XmlPath": "SampleFunction.xml"
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include xml comment

Written by

Microsoft MVP Azure Technologies / https://github.com/yuka1984 / Xamarin / .NET / ASP.NET Core / Web Front End / Azure

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