Hi there !
Today's article is brief and succinct , no theory as well , maybe just a sprinkle of theory , I promise , let's get into it !

The Problem We're Addressing Here

The point of having security tokens is to authenticate and authorize users while keeping their information safe while being sent back and forth between the server and the client , the token when issued from the authentication server , is sent to the client and it's then attached to every subsequent request so the server checks if it's valid based on a secret key used for encoding & decoding the token , but we're not here for that , this process takes up so much time to set up , and a lot of configuration just to start issuing tokens , in production , this's made possible by signing in with some user credentials , in response we receive a JWT Token , whereas in development , we may not want to write all the code just to have an authentication server , however , there's a tool that could help us issue tokens without any prior setup , so , now we know what we're concentrating on , let's begin.

Creating A New Project

We'll keep things simple , and for the sake of simplicity , we'll create a Minimal API project , so fire up your terminal , and type this command:

dotnet new web -n GenerateJwtTokens

The name is optional by the way.

Setting Up The Scene

For authentication and authorization to work , we need some basic configuration , start by doing the following:

1: Run this command to add a NuGet Package
dotnet add package Microsoft.AspNetCore.Authentication.JwtBearer

This package is used to add Jwt Bearer as our authentication scheme

2: Add both authorization and authentication services by adding these two lines of code to Program.cs:

3: Add the authorization middleware to the request pipeline by adding this line:

OK

Let's Create TOKENS

In your terminal , type out this command:

dotnet user-jwts create -n DonaldDuck

Press enter , and a new token for the name DonaldDuck will be created , if you copy the token and head to either https://jwt.ms/ or https://jwt.io/ , and paste it there , you should see something like this:

As you can see , there's some information inside the token and additionally , it's a valid token , see how easy and simple it is !

I'm not going to cover every possible option for this tool , however , you can check all the feasible options by using this command right here:

dotnet user-jwts -h

Before we do anything else , go to appsettings.development.json , you'll see that the file has been modified automatically to include some settings , this was done by the tool , those settings are used to issue the tokens so in case you were wondering where the valid audiences and valid issuer claims that you saw when you decoded the token came from , now you know !

The valid audience is every URL mentioned in launchSettings.json inside the Properties folder.

With the setup now completed , let's test it !

Testing The Generated JWT Token

I created a basic list of strings named values just for demonstration purposes , and added a new GET Endpoint that when called , retrieves all the values inside the values list , this endpoint requires authorization though , so for now , add the following highlighted lines:

Ok , we're all set , let's run the API , type this command:

dotnet run

Copy the URL and paste it in a tool like Postman or Insomnia , and then hit send , you should get a 401 Unauthorized as a response because we haven't supplied a token in the request's header , now go back to that token you generated for DonaldDuck , or create a new one , it doesn't matter , copy it and go to the authorization tab , and change the type to Bearer Token , then paste your token there , like this:

Now press send and voila , you get a 200 OK as a response with the values from our basic list , similar to the following:

Summary

In this article , I merely covered a single command , but I gave you the foundation on how to generate JWTs with as little as 3 steps , moreover , there're other commands that for example add a claim for the user role , you can clear all tokens issued for a project and possibly list all the issued tokens as well plus a lot more , so yes , the tool is a great way to save up time on configuring and setting up an entire authentication process.

I hope you found this useful !