There is a separate VSIX installer available for Visual Studio 2019 and Visual Studio 2022

REST API Client Code Generator

A collection of Visual Studio C# custom tool code generators for Swagger / OpenAPI specification files

Features

• Supports Visual Studio 2017
• Add New REST API Client to a project from an OpenAPI specification URL (e.g https://petstore.swagger.io/v2/swagger.json) using AutoRest, NSwag, Swagger Codegen, or OpenAPI Generator
• Define custom namespace for the generated file
• Auto-updating of generated code file when changes are made to the OpenAPI specification JSON or YAML file
• Generate code using an NSwagStudio specification file by including it in the project and using the Generate with NSwag context menu

Custom Tools

• AutoRestCodeGenerator - Generates a single file C# REST API Client using AutoRest. The resulting file is the equivalent of using the AutoRest CLI tool with: --csharp --input-file=[swaggerFile] --output-file=[outputFile] --namespace=[namespace] --add-credentials

• NSwagCodeGenerator - Generates a single file C# REST API Client using the NSwag.CodeGeneration.CSharp nuget package v13.14.8

• SwaggerCodeGenerator - Generates a single file C# REST API Client using Swagger Codegen CLI v3.0.34. The output file is the result of merging all the files generated using the Swagger Codegen CLI tool with: generate -l csharp --input-spec [swaggerFile] --output [output] -DapiTests=false -DmodelTests=false -DpackageName=[namespace] --skip-overwrite

• OpenApiCodeGenerator - Generates a single file C# REST API Client using OpenAPI Generator v6.2.1. The output file is the result of merging all the files generated using the OpenAPI Generator tool with: generate -g csharp --input-spec [swaggerFile] --output [output] -DapiTests=false -DmodelTests=false -DpackageName=[namespace] --skip-overwrite

Dependencies

The custom tool code generators piggy back on top of well known Open API client code generators like AutoRest, NSwag, OpenAPI Generator, and Swagger Codegen CLI. These tools require NPM and the Java Runtime Environment to be installed on the developers machine. Alternative Java SDK implementations such as the OpenJDK works fine with this extension. By default, the path to java.exe is read from the JAVA_HOME environment variable, but is also configurable in the Settings screen

The Swagger Codegen CLI and OpenAPI Generator are distributed as JAR files and are downloaded on demand but requires the Java SDK to be installed on the machine. AutoRest is installed on-demand via NPM as a global tool and uses the latest available version. This means that using these custom tools have an initial delay upon first time use.

NSwagStudio is stand alone UI tool for editing a .nswag specification file for generating code. This tool is optional to install and official installation instructions are available on the NSwag Wiki on Github. If NSwagStudio is not installed on the machine then the Visual Studio Extension will install the NSwag CLI via NPM as a global tool using the latest available version.

The OpenAPI Generator code generator produces code that depends on the RestSharp and JsonSubTypes NuGet packages

The NSwag code generator produces code that depends on the Newtonsoft.Json NuGet package

The Swagger Codegen CLI code generator produces code that depends on the RestSharp and JsonSubTypes NuGet packages

The AutoRest code generator produces code that depends on the Microsoft.Rest.ClientRuntime and Newtonsoft.Json NuGet packages

This Visual Studio Extension will automatically add the required NuGet packages that the generated code depends on

Screenshots

Settings

This extension will by default make some assumptions on the installation paths for Java, NSwag and NPM but also provides option pages for configuring this. The Swagger Codegen CLI and the OpenAPI Generator JAR files are by default downloaded to the user TEMP folder but it is also possible to specify to use existing JAR files

Supports customising how AutoRest generates code based on the C# generator settings that the AutoRest CLI tool provides

Supports customising how NSwag generates code using the properties exposed by the NSwag NuGet package

Supports customising how the .nswag file is generated using a subset of the options available in NSwag Studio

Supports customising how OpenAPI Generator generates code using the additional optional properties that the OpenAPI Generator CLI tool provides

This extension collects errors and tracks feature usages to a service called Exceptionless and Azure Application Insights. This is done anonymously using a support key and a generated anonymous identity based on a secure hash of username@host

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