A few months ago I put together a simple starter project for ASP.NET authorisation without any dependencies or configuration setup requirements. The motivation was my frustration with the complexity of the tutorials for something that should really be quite simple. I did leave the token based authorisation only partially complete however - there was no refresh token included which was an oversight on my part. Anyhow, I’ve gone ahead and done this plus a few other changes.

Token Based Authorisation

As mentioned this will now generate a refresh token upon login. The concept is simple - when your token times out you send it along with the refresh token and receive another so you can continue with your session. I’m not going to go down into too much detail - the whole point of the project was to provide a code sample so simple it’s easy to follow. There’s a service TokenService which has three public methods GenerateAccessToken, GenerateRefreshToken, and GetPrincipalFromExpiredToken. The first two are fairly obvious, the last is required so we can locate our refresh token in the database. That’s a minor change from the previous project - there’s now a database (of sorts!). Don’t worry though, it’s just a text file but it’s to simulate what you would do in a real world scenario - the refresh token would be saved against the logged in user.

There’s a new TokenController which has two actions Refresh and Revoke which again should be fairly obvious.

Putting it together

It works much the same as before. To login as the admin user run the following in your terminal.

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curl -X POST http://localhost:5000/api/login -H "Content-Type: application/x-www-form-urlencoded" -d "Name=admin&Password=password"

This will return something similar to the following.

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{"token":"eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJodHRwOi8vc2NoZW1hcy54bWxzb2FwLm9yZy93cy8yMDA1LzA1L2lkZW50aXR5L2NsYWltcy9uYW1lIjoiYWRtaW4iLCJodHRwOi8vc2NoZW1hcy54bWxzb2FwLm9yZy93cy8yMDA1LzA1L2lkZW50aXR5L2NsYWltcy9uYW1laWRlbnRpZmllciI6IjEiLCJodHRwOi8vc2NoZW1hcy5taWNyb3NvZnQuY29tL3dzLzIwMDgvMDYvaWRlbnRpdHkvY2xhaW1zL3JvbGUiOiJhZG1pbnMiLCJuYmYiOjE1MzI5ODI5OTYsImV4cCI6MTUzMjk4MzA1NiwiaXNzIjoiaHR0cDovL2xvY2FsaG9zdDo1MDAwL2FwaS8iLCJhdWQiOiJodHRwOi8vbG9jYWxob3N0OjUwMDAvYXBpLyJ9.PwL9AKuVh0yIheBG-bXMdK5X8Q1USzvE2gebYyBgVT0","refreshToken":"xmUsVDGtPpaMDqkkZqAwEv2T7n07zFwL31aYddf0WSY="

Save both the token and the refreshToken as variables your terminal as follows as we’ll need these in a bit.

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TOKEN_VALUE=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJodHR ...

REFRESH_TOKEN=xmUsVDGtPpaMDqkkZqAwEv2T7n07zFwL31aYddf0WSY=

The refreshToken will be saved against the user - if you open the users.json file you should see something like the following.

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{
  "Id": 1,
  "Name": "admin",
  "Password": "password",
  "RefreshToken": "xmUsVDGtPpaMDqkkZqAwEv2T7n07zFwL31aYddf0WSY=",
  "Groups": [
    {
      "Id": 1,
      "Name": "admins"
    },
    {
      "Id": 2,
      "Name": "superusers"
    },
    {
      "Id": 3,
      "Name": "users"
    }
  ]
}

You can then run your commands as before like the following.

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curl http://localhost:5000/api/admin -H "Authorization: Bearer $TOKEN_VALUE"

Which returns the following expected text.

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Only authenticated token based requests from admins receive this message

When this no longer works we just request a new token with the following.

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curl -X POST http://localhost:5000/api/token/refresh -H "Content-Type: application/x-www-form-urlencoded" -d "token=$TOKEN_VALUE&refreshToken=$REFRESH_TOKEN"

This will return json similar to that returned with the login step containing both the token and refreshToken.

To revoke the token at any time (if for example, when you wish to logout) run the following.

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curl -X POST http://localhost:5000/api/token/revoke -H "Authorization: Bearer $TOKEN_VALUE" -H "Content-Length: 0"

There’s now a signup method which allows you to create a new user. Once you’ve done this you can login as show earlier.

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curl -X POST http://localhost:5000/api/signup -H "Content-Type: application/x-www-form-urlencoded" -d "Name=test1&Password=password"

Other changes

I’ve created some example projects to keep the code size down for the different scenarios (since that was the whole point of the exercise). Below is the tree of the folder where they reside which is in the root of the repository.

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.
└── examples
    ├── api
    ├── cookies
    ├── cookies+api
    └── cookies+api+policies

To run all the tests as shown on the home page you probably should use the cookies+api project. I’ve removed ASP.NET policies from the projects as these aren’t actually necessary. You can use roles which does the same and the code base is now very small. I’ve kept the cookies+api+policies project for legacy purposes. The api and cookies projects are for when you only require one of those authentication types.

I should probably do some proper documentation as the home page is now slightly out of date and the repo is starting to expand a bit but I’ll see what the feedback is like.

Here’s the link to the code on Github.

Enjoy :-)