Identity Server: API Migration to ASP.NET Core 2

After writing the basic migration guide from ASP.NET Core 1.1.x to 2.0 I embarked on the task of upgrading the rest of the projects I have on GitHub. For the most part, it has been a pretty smooth transition. This post is going cover the differences that I hit while converting an API that is part of my IdentityServer sample project. This assumes that you have already followed my other migration post which can be found here.

Package Changes

The source of this conversion being different is that the  IdentityServer4.AccessTokenValidation NuGet package is not currently supported on ASP.NET Core 2. Token validation can be done using bits provided by the framework. This is the recommended path suggested by the IdentityServer team as posted on this issue. Longer term you may want to switch back if you have a need for more features not provided by the Microsoft implementation as pointed out in this issue.

As for the actual change, just remove the reference to  IdentityServer4.AccessTokenValidation from your project using the NuGet UI, Package Manager Console, or by editing the  csproj file.


All the rest of the changes are in the  Startup class. First, in the  Configure function  app.UseIdentityServerAuthentication gets replaced with  app.UseAuthentication.

In the  ConfigureServices function is now where JWT Bearer options are set up. First, we have to add the type of authentication the API is going to use and then the options for JWT Bearer are set, which will match the settings that were being used before with the IdentityServer package.

Wrapping up

With the above, your API can run on ASP.NET Core 2 and still verify authorization using IdentityServer4. My IdentityServer sample project is taking the longest to update so I would expect at least one or two more posts on the process as each of the projects gets upgraded.

Identity Server: External Authentication using Twitter

This post is going to cover adding authentication using Twitter to the same project that has been used in all of my IdentityServer examples. The same basic idea would apply to almost any third party authentication setup so this should give you a good starting point for any integration. The starting point of the code can be found here.

Create Twitter App

Before any code changes create a new application on Twitter via this page. Click Create New App to begin the process.

On the Create an application page enter all the requested information. Note that the website won’t allow a localhost address. If you don’t have a real address for your application just enter a random URL as I did here. When finished click Create your Twitter application.

Now that we have an application click on the Keys and Access Tokens tab. We will need both the Consumer Key and Consumer Secret when we get to the Identity Application.

Identity Application Changes

Now that we have a Twitter application ready to go let us dive into the changes needed to the Identity Application. The first step is to add a reference to Microsoft.AspNetCore.Authentication.Twitter via NuGet.

Next in the  ConfigureServices function of the  Startup class after  app.UseIdentityServer() add the following.

The first three options should a straight forward enough. The next two are the values from the Twitter application I mentioned above. In this example, I am storing the values using User Secrets which get pulled out of configuration. For more details on how to set up secrets, you can see this post.

The above are all the changes required. The Identity Application will now allow users to auth using Twitter.

Logging in using Twitter

As you can see below the login page now has a button for Twitter.

When the user chooses to log in using Twitter they are shown the following page where they must approve access to their Twitter account from your application.

If this is the first time a user has logged in with Twitter they will be prompted to enter an email address to finish registration.

Wrapping up

As you can see adding external authentication is super simple. Check out the Microsoft Docs on Twitter Auth (ASP.NET Core 2.0 so look out for differences if you are not on the preview bits) and IdentityServer Docs on External Auth for more information.

The finished code can be found here.


Identity Server: Changing Angular OpenID Connect Clients

Thanks to Andrew Stegmaier opening this issue on the repo that goes with my IdentityServer exploration I was made aware of a certified OpendID Connect client specifically written for Angular (4+). The angular-auth-oidc-client was created by damienbod. This post is going to cover the transition to this new client. The starting point of the code can be found here. All the changes discussed in this post take place in the ClientApp project.

Package Changes

In  package.json the following changes need to be made using your package manager of choice or manually changing the fill and doing a restore.

App Module Changes

Both  app.module.client.ts and  app.module.server.ts got a little cleanup to remove the duplicate provider code. The following lines were deleted from both files.

The  providers array moved to using providers imported from  app.module.shared.ts.

Next, in  app.module.shared.ts the following imports were removed.

Then, the following import for the OpenId Connect client was added.

In the  declarations array  CallbackComponent was removed. In the  imports array  AuthModule.forRoot() was added. The route for  CallbackComponent was removed and the  canActivate condition was removed from the  fetch-data route. Finally, the  providers section is reduced to only the  AuthService. That was a lot of changes, so I am including the full finished class below.

File Deletions

The following files were completely removed. Some of them may come back in a different form, but for the moment the functions they were handling are being dealt with in a different way.

Auth Service

The  AuthService class was pretty much rewritten since it is at the core of the interaction with the OpenId Connect client. It still contains pretty much all the functionality as before just using the new client. The following is most of the class. I removed all of the HTTP calls except for  get to save space.

It doesn’t show the best in the world here so be sure and check it out on GitHub. All the IdentityServer configuration is done in the  constructor using the  OpenIDImplicitFlowConfiguration class.

Navigation Component

The  NavMenuComponent class now needs some changes to match the new  AuthService. First, the following change to the imports.

The  AuthService class now provides the ability to subscribe to changes in the user’s authorization. To handle the subscription and unsubscription the class will implement both OnInit and  OnDestroy. Here is the new class declaration.

Next, here is the implementation of ngOnInit which handles the subscription to the change in  isAuthorized.

Then,  ngOnDestroy handles the unsubscription.

The class level variable for  _loggedIn is replaced with the following two variables.

The  constructor has been greatly simplified and now only takes an instance of the  AuthService.

Finally, the  login and  logout functions have changed to match the new function names in the  AuthService class.

Navigation Component UI

In the  navmenu.component.html file, a couple of tweaks are required based on the new variable names used above. The first set is related to showing either Login or Logout.

The final change in this file was to make the link to  fetch-data only show if the user is logging instead of sending the user to an unauthorized view.

Fetch Data Component

The final changes for the conversion to the new client are in the  fetchdata.component.ts and they are only needed because of a rename of the HTTP Get helper in the  AuthService.

Wrapping Up

This change took a lot of changes, but in the long run, it is going to be a better choice since the new client is focused on Angular. Another great thing about this client is they are looking into ways to handle the first load not remembering the user is logged in due to server side rendering (issue #36).

The finished code for this post can be found here.

Identity Server: Calling Secured API from Angular

This post is a continuation of a series of posts that follow my initial looking into using IdentityServer4 in ASP.NET Core with an API and an Angular front end. The following are the related posts.

Identity Server: Introduction
Identity Server: Sample Exploration and Initial Project Setup
Identity Server: Interactive Login using MVC
Identity Server: From Implicit to Hybrid Flow
Identity Server: Using ASP.NET Core Identity
Identity Server: Using Entity Framework Core for Configuration Data
Identity Server: Usage from Angular

This post is going to take the solution from last week, the code can be found here, and add an example of the Client Application (Angular) calling an endpoint on the API Application that requires a user with permissions.

API Application

To provide an endpoint to call with minimal changes this example just moves the SampleDataController from the Client Application to the API Application. The following is the full class.

Make special note that this class now has the  Authorize attribute applied which is the only change that was made when moving the file from the Client Application. This attribute is what will require an authorized user for all the routes this controller services.

Client Application

In the Client Application, the first step is to remove the  SampleDataController since it is now in the API Application.

Next, in the  app.module.client.ts file, add a new provider which can be used to supply the URL of the API to the rest of the Client Application. Don’t take this as best practices for injecting configuration data it is just an easy way to handle it in this application. The following is the full class without the imports (which haven’t changed) the new item is the  API_URL.

Now for the changes that need to be made to the  FetchDataComponent which is the class that will call the new API endpoint. First, add an import for the  AuthService.

Next, there are a couple of changes to the signature of the constructor. The first is to use  'API_URL' instead of  'ORIGIN_URL'. The second is to provide for injection of the  AuthService. The following is a comparison between the version of the constructor signature.

The final change is to use  authService.AuthGet with the new URL instead of  http.get.

With the above changes, the user has to be logged in or the API will respond with not authorized for the weather forecasts end point. The Client Application doesn’t have anything to provide the user with the fact they aren’t authorized at the moment, but that is outside the scope of this entry.

So far we haven’t look at the code in the  AuthService class, but I do want to explain what the  AuthGet function is doing and the related functions for put, delete, and post. These calls are wrappers around the standard Angular HTTP library calls that add authorization headers based on the logged in user. The following is the code of the  AuthGet as well as two helper functions the class uses to add the headers.

Wrapping up

It feels like this application is finally getting to the point where other development could happen if it were more than a demo, which is exciting. My thought on how this could be used for real applications is the Identity Application would stand on its own and be used by many clients. The Client Application with a few more tweaks could be used as a template for Angular applications. The completed code can be found here.

This post finishes up the core of what I set out to learn about IdentityServer, but there could be more related posts as I continue to add some polish to the current implementation of the sample solution.

Identity Server: Usage from Angular

This post is a continuation of a series of posts that follow my initial looking into using IdentityServer4 in ASP.NET Core with an API and an Angular front end. The following are the related posts.

Identity Server: Introduction
Identity Server: Sample Exploration and Initial Project Setup
Identity Server: Interactive Login using MVC
Identity Server: From Implicit to Hybrid Flow
Identity Server: Using ASP.NET Core Identity
Identity Server: Using Entity Framework Core for Configuration Data
Identity Server: Usage from Angular (this post)

This post is finally going to add login from Angular in the Client Application. It has been a long time coming and will be a starting point, based on a few examples I found which I will list at the end. The starting point of the code can be found here.

API Application

In order for the Client Application to be able to call the API Application, there are some changes needed to allow cross-origin resource sharing. For more details check out this post only the basics will be covered here. First, add the following NuGet package.

  • Microsoft.AspNetCore.Cors

Next, in the  ConfigureServices function of the  Startup class add AddCors before AddMvc. The following is the full function. This allows calls to the API Application from the Client Application which is running on localhost on port 5002.

Then, in the  Configure function add  app.UseCors("default"); to make sure the default policy defined above is enforced. The following is the full function.

Identity Application

The Identity Application doesn’t have a lot of changes, but some of the configuration between it and the Client Application is what took me the bulk of time getting the code for this post setup and going.

If you are keeping up with the series then last you will know last week all the configuration data was moved to a database using Entity Framework Core. This is a bit of a problem now that I need to add a new client and the configuration data doesn’t any associated UI. To work around this I just added the new client to the  Config class in the  GetClients function and then deleted the existing database and let Entity Framework recreate it based on the new seed data. Not optimal, but I didn’t want to complicate things by adding a UI for the client setup. The following is the new client.

There are a few things in this configuration that took me some time to get right. First of all best, I have been able to tell with this style of application implicit flow is the way to go which is handled by using a  GrantTypes.Implicit for the  AllowedGrantTypes.

The next issues I ran was a cross-origin resource sharing issue. Thankfully IdentityServer makes it easy to specify what origins should be allowed using the  AllowedCorsOrigins property. In this example, we want to allow requests from the URL of our Client Application which is http://localhost:5002.

The last issue I had on was with the URIs I had set. The configuration in IdentityServer needs to exactly match the setup in the Client Application or you will have issues. I also had trouble trying to use the raw base address (http://localhost:5002) as the  PostLogoutRedirectUris so look out for that as well.

Client Application

In the client application open the  package.json file and add the following the  dependencies section.

I also updated the typescript version to 2.3.4. Be cautious when changing the version of typescript as there is an issue with Angular and typescript 2.4.x at the moment.

At this point in the process, I had to find some resources on how to continue. The following are the ones I leaned on most.

ASP.NET Core & Angular2 + OpenID Connect using Visual Studio Code
Repo for the previous link
Repo for with example Angular OidcClient

Getting this part of the application working involved a lot of changes and instead of going in depth on everything I am going to recommend just copying in the following files for the finished example code and dig more into them after you get an example working. Here is the list of files.

  • ClientApp/ClientApp/app/components/callback/callback.component.ts
  • ClientApp/ClientApp/app/components/services/ – whole directory
  • ClientApp/ClientApp/boot-server.ts – related to a typescript error only if needed

With the above files in place, we will now focus on using the functionality they provide to log in and protect routes. To begin   app.module.client.tsapp.module.server.ts and  app.module.shared.ts all need the next set of changes. I haven’t tried it yet, but I bet this change could just be made in the shared file and used in the other two. Add the following imports.

Next, add the same three items to the array of providers (or add one if it doesn’t exist). The following is an example from the shared file.

Finally, in the shared file change any routes that you would like to require the user to be logged in to be like the following which utilizes the  canActivate of the route.

In the  navmenu.component.html which is the UI for the navigation menu add the following two options to the unordered list.

The user will only ever see one of the above options based on being logged in or not which is what the  *ngIf is doing.

The navigation view model ( navmenu.component.ts) changed a bit more. The following is the complete file.

New imports were added for the  AuthService and  GlobalEventsManager which get injected into the constructor of the class. The class also contains a _loggedIn property to track if the user is logged in or not. Finally, functions were added for  login and  logout to go with the two new links shown in the navigation.

Wrapping up

With the above, the Client Application can now log a user in and out utilizing IdentityServer from Angular. There are a lot of details in the files we just copied, but with a working sample, it is much easier to examine/customize how the process is being handled. Check back next week to see how to call the API Application from the Angular part of the Client Application.

The completed code can be found here.