GitHub Repository

An example of this code can be found at


Ever wondered if there was an easy way of turning your C# DTOs into TypeScript interfaces? Every wondered if we could automatically generate a TypeScript client for our API, rather than having to manually write out the function for every endpoint? Turns out the answer is yes, here’s how:

Generate The Swagger Definition

If you’ve recently created a .NET Web API you’ll know it automatically opens up Swagger when you run the application. However it doesn’t create a swagger.json file that is copied to your project folder.

Let’s get a swagger.json being generated:

Install Swashbuckle CLI

Run the following commands in your API project:

dotnet new tool-manifest
dotnet tool install Swashbuckle.AspNetCore.Cli

Add A New Post-Build Command

Add the following task to your API csproj which will generate a swagger.json file from our API build, and then copy that file into our Vue.js directory, so we can access it using npm commands.

<Target Name="OpenAPI" AfterTargets="Build">
    <Exec Command="dotnet tool restore" WorkingDirectory="$(ProjectDir)" />
    <Exec Command="dotnet swagger tofile --output ../Solar.Vue/references/swagger.json $(OutputPath)$(AssemblyName).dll v1" WorkingDirectory="$(ProjectDir)" />

If you now build the project, you should find a swagger.json file under Solar.Vue/references/.

Generate The TypeScript Client

Now we have our hands on a swagger.json we now need to build a TypeScript client. There are a couple of steps:

Install OpenAPI Tools

Install the following npm package:

npm i @openapitools/openapi-generator-cli -D

OpenAPI Tools is the officially supported package for everything OpenAPI/Swagger (see

Install Java

The above generator requires Java to be installed. If you’re on windows you can easily install it using chocolatey:

choco install oraclejdk

NPM Script

And finally, we need to add a npm script to build the client:

"generate-api-client": "openapi-generator-cli generate -i ./references/swagger.json -g typescript-axios -o ./src/api/"
  • ./references/swagger.json defines where the definition is
  • ./src/api defines where the client should be created
  • typescript-axios is a type of client (specifically written in TypeScript and using axios for http calls)


You will now have a fully fledged TypeScript client with DTO types. Here is an example of how you can use it!

import { AccountApi } from "@/api";

const api = new AccountApi();

const result = await api.userLoginPost({
  email: "[email protected]",
  password: "password",