Pass ASP.NET Core Appsettings Values to Angular via an API Call

There have been a few issues opened on the repo I have showing usage of Angular, Identity Server 4, and ASP.NET Core together that related to incompatibilities with the newer versions of Angular. In an effort to fix this issue the plan was to recreate the client application using the new Angular template from Microsoft which from what I read should address the issue.

The code before any changes can be found here, but in this case, the whole client application has been recreated so the starting point may not be super helpful.

The Problem

For the most part, this worked well, but the problem can when I needed to use some configuration values from ASP.NET Core in my new Angular application. The previous versions of the template used server-side rendering which I utilized to pass the configuration values. The new template doesn’t use server-side rendering by default and I wanted to find a way to solve the issue without requiring server-side rendering.

The other issue is that I want to be able to run this application in Azure and set the configuration values as environment variables. While Angular seems to have support for environment files finding a solution that used a systems environment variables turned out too not be simple.

Configuration API Endpoint

Since the configuration values I need to get to the client application are secret I decided to go the route of pulling them via an API call back to the same ASP.NET Core application that is hosting the Angular Application, which is the Client App project in the sample solution.

I added a ConfigurationController.cs class to the Controller directory with the following contents.

[Produces("application/json")]
[Route("api/Configuration")]
public class ConfigurationController : Controller
{
    private readonly IConfiguration _configuration;

    public ConfigurationController(IConfiguration configuration)
    {
        _configuration = configuration;
    }

    [HttpGet("[action]")]
    public IActionResult ConfigurationData()
    {
        return Ok(new Dictionary<string, string>
        {
            { "IdentityServerAddress", _configuration["IdentityServerAddress"] },
            { "ApiAddress", _configuration["ApiAddress"] }
        });
    }
}

This controller gets constructed with a reference to the application’s configuration which is then used to populate a dictionary with the values my Angular application needs. For completeness, the following is the contents of the application’s appsettings.json file.

{
  "Logging": {
    "LogLevel": {
      "Default": "Warning"
    }
  },
  "IdentityServerAddress": "http://localhost:5000",
  "ApiAddress": "http://localhost:5001/api/"
}

Angular Changes

This is the part that I really struggled to get right. I needed the configuration values from the API above to be available as soon as possible. Thankfully I came across this blog post by Juri Strumpflohner which covers using Angular’s APP_INITIALIZER.

The first thing I need was to create a class in Angular to get the configuration values from the API and serve to them the rest of the Angular application. To do this I added a configuration.service.ts into a new ClientApp/src/app/configuration directory. The full class follows.

import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';

@Injectable()
export class ConfigurationService {

  private configuration: IServerConfiguration;

  constructor(private http: HttpClient) { }

  loadConfig() {
    return this.http.get<IServerConfiguration>('/api/Configuration/ConfigurationData')
      .toPromise()
      .then(result => {
        this.configuration = <IServerConfiguration>(result);
      }, error => console.error(error));
  }

  get apiAddress() {
    return this.configuration.ApiAddress;
  }

  get identityServerAddress() {
    return this.configuration.IdentityServerAddress;
  }

}

export interface IServerConfiguration {
  ApiAddress: string;
  IdentityServerAddress: string;
}

This class hits the API to get the configuration values in the loadConfig function and maps it to a class level field. It also provides properties to get the individual configuration values.

As I mentioned above, getting the application to get these configuration values in a timely matter was something I really struggled to do. The first step to using Angular’s APP_INITIALIZER to solve this issue is to change the import from @angular/core to include APP_INITIALIZER and to import the ConfigurationService.  All these changes are being made in the app.module.ts file.

import { NgModule, APP_INITIALIZER } from '@angular/core';
import { ConfigurationService } from "./configuration/configuration.service";

Next, we need to define a function that will call the ConfigurationService.loadConfig function.

const appInitializerFn = (appConfig: ConfigurationService) => {
  return () => {
    return appConfig.loadConfig();
  };
};

Finally, in the providers array add an element for the APP_INITIALIZER and the ConfigurationService.

providers: [
  ConfigurationService,
  {
    provide: APP_INITIALIZER,
    useFactory: appInitializerFn,
    multi: true,
    deps: [ConfigurationService]
  }]

 Wrapping Up

This is one of those things that turned out to be way more complicated than I expected. Thankfully with the above changes, I was able to get it working. I hope this saves you all some time. The code with all the changes can be found here.

ASP.NET Core 2 Fails to Publish With Angular 5

I had an issue opened on my Identity Server GitHub repo saying that publishing the client application fails with something like the following error when using server-side rendering.

Can’t resolve ‘./../$$_gendir/ClientApp/app/app.module.browser.ngfactory’

This was only an issue after moving the project to target Angular 5. After some research, it turns out that Angular tools for Webpack has to use a different plugin for ahead of time compiling for Angular 5+. I ended up finding a fix in this issue.

The Fix

In order to resolve the issue, I made the following changes in the webpack.config.js file. The first change is in the require statements at the top of the file.

Before:
const AotPlugin = require('@ngtools/webpack').AotPlugin;

After:
const AngularCompilerPlugin = require('@ngtools/webpack').AngularCompilerPlugin;

Next, make the following replacement in the rest of the file, which should only be two places.

Before:
new AotPlugin

After:
new AngularCompilerPlugin

Wrapping Up

Most of the projects I reference on this blog are written to specifically target the topic I am trying to cover and as such I miss things like testing publish since I’m never going to production with these applications. I really appreciate those of you who find issues and take the time to open an issue on GitHub. Keep them coming, and if you find a solution before I do feel free to submit a pull request.

 

Trying the New ASP.NET Core Angular Template with CLI Support

I got hit by the flu that has been going around and now that the fever has passed I thought it would be a good time to try out the new version of the Angular template for ASP.NET Core that works well with the Angular CLI.

Template Installation

Note that at the time of this writing the templates are in the release candidate stage and a new version could be available by the time you are reading this so make sure and check this page for potential updates.

Running the following command from a command prompt will install the RC version of the templates.

dotnet new --install Microsoft.DotNet.Web.Spa.ProjectTemplates::2.0.0-rc1-final

Project Creation

Create a directory for the project and navigate to it in a command prompt. Run the following command to create the new Angular project.

dotnet new angular

Next, if you have a solution you want to add the new project to that can be done with the following command adjusting for the naming of your project and solution.

dotnet sln "ASP.NET Core Basics.sln" add src\AngularWithCli\AngularWithCli.csproj

Installation of Angular CLI

From the command prompt run the following command to install the Angular CLI globally.

npm install -g @angular/cli

After the above, I got the following error trying to run any Angular CLI commands.

You seem to not be depending on “@angular/core”. This is an error.

The problem ended up being that I had not installed all the packages for the project. The issue was cleared up by the following command.

npm install

Angular CLI Usage

Navigate to the ClientApp directory and you can then use all the Angular CLI commands as you would in a stand along Angular application. Some of which can be found here. If you are looking for a quick command to verify all is work the following command works well by running a linter on your project.

ng lint

Wrapping Up

Having templates that are compatible with the Angular and React CLI is a big step forward. The CLIs provide a lot of functionality and by having a setup that doesn’t restrict their usages is a great move. Make note that server-side rendering is no longer enabled by default, but can still be enabled for Angular projects, but not React based projects.

I recommend you check out the official documentation which can be found here.

I hope we see these functionality moves to the other templates that are outside of the templates in this package in order to support Aurelia and Vue.

Identity Server: Migration to version 2.1 and Angular HTTP Changes

Version 2.1 of Identity Server 4 was released a few weeks and this post is going to cover updating my sample project to the latest version. The starting point of the code can be found here. We are going to tackle this in sections as there are updates needed for an ASP.NET Core Update, Identity Server Update, and some broken bits in Angular.

ASP.NET Core Update

The sample projects were all on ASP.NET Core version 2.0.0. For each project right-click and select Edit ProjectName.csproj. Make the following change.

Before:
<PackageReference Include="Microsoft.AspNetCore.All" Version="2.0.0" />

After:
<PackageReference Include="Microsoft.AspNetCore.All" Version="2.0.3" />

Identity Server Update

Right-click the Identity App project and select Edit IdentityApp.csproj. Next, make the following changes.
Before:
<PackageReference Include="IdentityServer4.EntityFramework" Version="2.0.0" />

After:
<PackageReference Include="IdentityServer4.EntityFramework" Version="2.1.0" />

Next, need to add a couple of Entity Framework migrations to see if there were any data changes with the following commands from a command prompt in the Identity App project directory.

dotnet ef migrations add Configration21 -c ConfigurationDbContext -o Data/Migrations/IdentityServer/Configuration
dotnet ef migrations add PersistedGrant21 -c PersistedGrantDbContext -o Data/Migrations/IdentityServer/PersistedGrant

Turns out that there were no data changes for this version so if you are on version 2.0.0 you can skip this step.

Angular Issues

I’m not sure how I didn’t hit this issue on the last update post, but the Client App needs to be changed to use the new Angular HttpClient. I got the following error when trying to run the client application.

An unhandled exception occurred while processing the request.

NodeInvocationException: No provider for PlatformRef!
Error: No provider for PlatformRef!
at injectionError
After some digging, I tracked the issue down to using HttpModule instead of HttpClientModule. To make this transition we need to make a few changes. In the app.module.shared.ts make the following changes to the imports section.
Before:
import { HttpModule } from '@angular/http';

After:
import { HttpClientModule } from '@angular/common/http';

Next, in the imports array make the following change.

Before:
HttpModule

After:
HttpClientModule

Next, in the webpack.config.vendor.js fille add the following to the vendor array.

'@angular/common/http'

The last changes are to the auth.service.ts and they are extensive so instead of going through them I’m just going to post the full class after all the changes.

import { Injectable, Component, OnInit, OnDestroy, Inject } from '@angular/core';
import { HttpClient, HttpHeaders } from '@angular/common/http';
import { Observable } from 'rxjs/Rx';
import { Subscription } from 'rxjs/Subscription';

import { OidcSecurityService, OpenIDImplicitFlowConfiguration } from 'angular-auth-oidc-client';

@Injectable()
export class AuthService implements OnInit, OnDestroy {
    isAuthorizedSubscription: Subscription;
    isAuthorized: boolean;

    constructor(public oidcSecurityService: OidcSecurityService,
        private http: HttpClient,
        @Inject('ORIGIN_URL') originUrl: string,
        @Inject('IDENTITY_URL') identityUrl: string
    ) {
        const openIdImplicitFlowConfiguration = new OpenIDImplicitFlowConfiguration();
        openIdImplicitFlowConfiguration.stsServer = identityUrl;
        openIdImplicitFlowConfiguration.redirect_url = originUrl + 'callback';
        openIdImplicitFlowConfiguration.client_id = 'ng';
        openIdImplicitFlowConfiguration.response_type = 'id_token token';
        openIdImplicitFlowConfiguration.scope = 'openid profile apiApp';
        openIdImplicitFlowConfiguration.post_logout_redirect_uri = originUrl + 'home';
        openIdImplicitFlowConfiguration.forbidden_route = '/forbidden';
        openIdImplicitFlowConfiguration.unauthorized_route = '/unauthorized';
        openIdImplicitFlowConfiguration.auto_userinfo = true;
        openIdImplicitFlowConfiguration.log_console_warning_active = true;
        openIdImplicitFlowConfiguration.log_console_debug_active = false;
        openIdImplicitFlowConfiguration.max_id_token_iat_offset_allowed_in_seconds = 10;

        this.oidcSecurityService.setupModule(openIdImplicitFlowConfiguration);

        if (this.oidcSecurityService.moduleSetup) {
            this.doCallbackLogicIfRequired();
        } else {
            this.oidcSecurityService.onModuleSetup.subscribe(() => {
                this.doCallbackLogicIfRequired();
            });
        }
    }

    ngOnInit() {
        this.isAuthorizedSubscription = this.oidcSecurityService.getIsAuthorized().subscribe(
            (isAuthorized: boolean) => {
                this.isAuthorized = isAuthorized;
            });
    }

    ngOnDestroy(): void {
        this.isAuthorizedSubscription.unsubscribe();
        this.oidcSecurityService.onModuleSetup.unsubscribe();
    }

    getIsAuthorized(): Observable<boolean> {
        return this.oidcSecurityService.getIsAuthorized();
    }

    login() {
        console.log('start login');
        this.oidcSecurityService.authorize();
    }

    refreshSession() {
        console.log('start refreshSession');
        this.oidcSecurityService.authorize();
    }

    logout() {
        console.log('start logoff');
        this.oidcSecurityService.logoff();
    }

    private doCallbackLogicIfRequired() {
        if (typeof location !== "undefined" && window.location.hash) {
            this.oidcSecurityService.authorizedCallback();
        }
    }

    get(url: string): Observable<any> {
        return this.http.get<any>(url, { headers: this.getHeaders() });
    }

    put(url: string, data: any): Observable<any> {
        const body = JSON.stringify(data);
        return this.http.put<any>(url, body, { headers: this.getHeaders() });
    }

    delete(url: string): Observable<any> {
        return this.http.delete<any>(url, { headers: this.getHeaders() });
    }

    post(url: string, data: any): Observable<any> {
        const body = JSON.stringify(data);
        return this.http.post<any>(url, body, { headers: this.getHeaders() });
    }

    private getHeaders() {
        let headers = new HttpHeaders();
        headers = headers.set('Content-Type', 'application/json');
        return this.appendAuthHeader(headers);
    }

    private appendAuthHeader(headers: HttpHeaders) {
        const token = this.oidcSecurityService.getToken();

        if (token === '') return headers;

        const tokenValue = 'Bearer ' + token;
        return headers.set('Authorization', tokenValue);
    }
}

With all those changes made run the following two commands in a command prompt in the Client App project directory.

node node_modules/webpack/bin/webpack.js --config webpack.config.vendor.js
node node_modules/webpack/bin/webpack.js

Wrapping up

This post ended up being more about Angular than Identity Server, but it is nice to have everything upgraded to the latest and working.

The files in the completed can be found here.

Identity Server: Upgrade Client to Angular 5

I have been working a lot on my basics sample project to explore some new client-side frameworks (React and Vue if you are interested). Since I have been away from the Identity Server sample for a while I thought it would be good to see what updates the project might need. It turns out that Angular was the big thing that was out of date. This post is going to cover the changes to get the project updated to Angular 5.

Package.json

In the Client App project open the package.json file and update the version of the @angular packages to at least the following version, and of course feel free to pin the exact version. I don’t just because of the nature of this sample.

"@angular/animations": "^5.0.0",
"@angular/common": "^5.0.0",
"@angular/compiler": "^5.0.0",
"@angular/compiler-cli": "^5.0.0",
"@angular/core": "^5.0.0",
"@angular/forms": "^5.0.0",
"@angular/http": "^5.0.0",
"@angular/platform-browser": "^5.0.0",
"@angular/platform-browser-dynamic": "^5.0.0",
"@angular/platform-server": "^5.0.0",
"@angular/router": "^5.0.0"

At this point, I tried to run and got an error about the version of rxjs being used. Instead of just blindly going package by package and seeing which versions were required I installed the Angular CLI and created a new Angular 5 application and used it as an example of what version I needed. Use the following commands if you would like to follow the same process since the current versions have changed by the time you are reading this post.

npm install -g @angular/cli
ng new sample-app

The above led me to the following version changes.

"rxjs": "^5.5.2",
"zone.js": "^0.8.14"

Attempt 2

At this point, I tried running the application again and received the following error.

Error: Version of @angular/compiler-cli needs to be 2.3.1 or greater. Current version is “5.0.1”.

As you can imagine I was surprised that 5.0.1 < 2.3.1. Turns out this is related to the version of @ngtools/webpack. This package deals with ahead-of-time compiling which my sample application uses, but the application I generated using the Angular CLI doesn’t. Updating to the following version cleared up the issue.

"@ngtools/webpack": "^1.8.0"

Open ID Connect Client

There was a much new version of the Open ID Connect Client that the Angular application is using so I upgrade it as well to the following version.

"angular-auth-oidc-client": "3.0.4"

This version dropped the startup_route so the following line had to be removed from the AuthService class.

openIdImplicitFlowConfiguration.startup_route = '/home';

Final Steps

Now that the package versions are sorted run the following commands from a command prompt to make sure that all the new version are installed and in the proper places.

npm install
node node_modules/webpack/bin/webpack.js --config webpack.config.vendor.js
node node_modules/webpack/bin/webpack.js

Wrapping Up

I am glad to have this upgrade done. It seems that every time I do one of these upgrades I end up down some rabbit hole. On the plus side, I seem to be getting faster at resolving the rabbit hole issues, or the frameworks have made a lot of progress on making sure the upgrade processes are simpler than they used to be. Either way, I get to expand my knowledge. I just need to schedule a bit more time before attempting upgrades.

The code in its finished state can be found here.

Identity Server: Deploy to Azure

This post is going to cover taking the existing set of applications we have been using to learn about Identity Server and deploying them to Azure. The starting point of the code can be found here.

Prep Work

The applications as they stand from the link above are not ready to be pushed to Azure most due to some configuration changes that are needed. We will go through each of the applications and take the hard-coded values and move them to appsettings.json.

API Application Configuration

The API application needs two configuration values for the address of the Identity Application and the address of the Client Application. The following two lines need to be added to the application’s appsettings.json file.

"IdentityServerAddress": "http://localhost:5000",
"ClientAddress": "http://localhost:5002"

Then in the Startup class, the values need to be used. The Identity Server address is used in the JWT Bearer setup.

Before:
o.Authority = "http://localhost:5000";

After:
o.Authority = Configuration["IdentityServerAddress"];

Then the Client address is used in the CORS setup.

Before:
policy.WithOrigins("http://localhost:5002")

After:
policy.WithOrigins(Configuration["ClientAddress"])
Identity Application Configuration

The Identity application needs a configuration value for the address of the address of the Client Application. The following line needs to be added to the application’s appsettings.json file.

"ClientAddress": "http://localhost:5002"

Next, the Config class needs a reference to configuration passed into the GetClients function.

public static IEnumerable<Client> GetClients(IConfiguration configuration)

Next, the references to http://localhost:5002 need to be replaced with the value from the configuration. The following is one example.

Before:
RedirectUris = { "http://localhost:5002/signin-oidc" },

After:
RedirectUris = { $"{configuration["ClientAddress"]}/signin-oidc" },
Identity Application Entity Framework

As part of publishing this set of applications, this example is going to use Azure SQL and right now the application is set up to use SQLite. In the Startup class replace UseSqlite with UseSqlServer. The following is an example of one of the needed replacements.

Before:
options.UseSqlite(Configuration.GetConnectionString("DefaultConnection")));

After:
options.UseSqlServer(Configuration.GetConnectionString("DefaultConnection")));

When switching database providers make sure to delete and recreate your database migrations. I didn’t to begin with and it cost me a lot of time in changing down a strange error which this post covers.

Client Application Configuration

The Client application needs two configuration values for the address of the Identity Application and the address of the API Application. The following two lines need to be added to the application’s appsettings.json file.

"IdentityServerAddress": "http://localhost:5000",
"ApiAddress": "http://localhost:5001/"

Then in the Startup class, the Identity Server Address needs to be used in the AddOpenIdConnect call.

Before:
options.Authority = "http://localhost:5000";

After:
options.Authority = Configuration["IdentityServerAddress"];

Next, the configuration values need to be passed to the Angular application. This process ended up being harder to figure out that I had anticipated and turned into a full blog post on its own. See this post for the details. The code for all the changes will also be on GitHub in case you need to the the diff for the client application.

Publish to Azure

Right-click on the Identity Application and select Publish.

This will show the Publish screen which provides the option to publish to Azure. We don’t have an existing App Service so we are going to create a new one. This page in the official docs explains all the options available on the publish screen. Click the publish button to continue.

The next screen that shows is the Create App Service Screen. I used all the default values and created a new Resource Group and App Service Plan. Keep in mind that the resource group and plan will be reused for the remaining two applications we are looking deploy. The only thing that will change between the applications on this screen will be the App Name.

The services tab looks like the following.

Next in the additional resources box lets hit the plus button next to SQL Database since our group of applications is going to need somewhere to store data. This will take us to the Configure SQL Database screen.

Since I don’t already have a SQL Server setup I am going to hit the New button to add one. That results in the next screen where you enter a name for the server as well as a username and password. After entering the required information click OK.

This will put you back on the configure database screen with most of it filled out. Make sure to set the database name you want to use.

Finally back on the Create App Service screen, you will see all the resources that you selected and configured. When you are satisfied with what you see click the Create button and let Azure do its magic.

When it is done you will see the profile now listed on the Publish page.

The above needs to be repeated for both the API and Client Applications, but using the Resource Group and App Service plan created above. Each profile should use a unique application name.

Identity Application Azure Configuration

The Identity Application needs access to the database that we created above. This means we need to set the DefaultConnection. The first step is to determine what the connection string should be. On the Azure Portal in your list of resources select the SQL database that we created above.

On the next page copy the provided connection string. Now navigate to the Identity App Service and under the Settings section select Application settings. Scroll down and find the Connection strings section and enter the copied value as the DefaultConnection.

Just above the Connection strings section we also need to enter a few values in the App settings section. For the Identity Application, we need the Twitter key and secret as well as the address of the client application. The following is a screenshot minus the actual values.

For the ClientAddress use the URL found in the Overview of the Client App’s App Service page.

API Application Azure Configuration

From the list of resources select the API App’s App Service page and in the Settings section select Application settings. In the App settings section add values for IdentityServerAddress and ClientAddress. As with the ClientAddress above the URLs for each application can be found on their respective App Service pages.

Client Application Azure Configuration

From the list of resources select the Client App’s App Service page and in the Settings section select Application settings. In the App settings section add values for IdentityServerAddress and ApiAddress.

Wrapping Up

At this point, you should be able to load up the application at the client address provided by Azure and have a working application. Overall the deployment to Azure was pretty easy. Getting the applications prepared to be deployed was a bit more challenging and sent me down a couple of rabbit holes. The code in its final state can be found here.

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.

app.UseTwitterAuthentication(new TwitterOptions
{
    AuthenticationScheme = "Twitter",
    DisplayName = "Twitter",
    SignInScheme = "Identity.External",
    ConsumerKey = Configuration["Authentication:Twitter:ConsumerKey"],
    ConsumerSecret = Configuration["Authentication:Twitter:ConsumerSecret"]
});

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.

Remove:
"oidc-client": "1.3.0",
"babel-polyfill": "6.23.0"

Add:
"angular-auth-oidc-client": "^1.3.1"

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.

import { AuthService } from './components/services/auth.service';		
import { GlobalEventsManager } from './components/services/global.events.manager';		
import { AuthGuardService } from './components/services/auth-guard.service';

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

Before:
providers: [
    AuthService, AuthGuardService, GlobalEventsManager
]

After:
providers: [
    ...sharedConfig.providers
]

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

import { CallbackComponent } from './components/callback/callback.component';
import { GlobalEventsManager } from './components/services/global.events.manager';

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

import { AuthModule } from 'angular-auth-oidc-client';

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.

import { NgModule } from '@angular/core';
import { RouterModule } from '@angular/router';

import { AppComponent } from './components/app/app.component'
import { NavMenuComponent } from './components/navmenu/navmenu.component';
import { HomeComponent } from './components/home/home.component';
import { FetchDataComponent } from './components/fetchdata/fetchdata.component';
import { CounterComponent } from './components/counter/counter.component';
import { UnauthorizedComponent } from './components/unauthorized/unauthorized.component';

import { AuthModule } from 'angular-auth-oidc-client';
import { AuthService } from './components/services/auth.service';

export const sharedConfig: NgModule = {
    bootstrap: [ AppComponent ],
    declarations: [
        AppComponent,
        NavMenuComponent,
        CounterComponent,
        FetchDataComponent,
        HomeComponent,
        UnauthorizedComponent
    ],
    imports: [
        AuthModule.forRoot(),
        RouterModule.forRoot([
            { path: '', redirectTo: 'home', pathMatch: 'full' },
            { path: 'home', component: HomeComponent },
            { path: 'unauthorized', component: UnauthorizedComponent },
            { path: 'counter', component: CounterComponent },
            { path: 'fetch-data', component: FetchDataComponent  },
            { path: '**', redirectTo: 'home' }
        ])
    ],
    providers: [ AuthService ]
};

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-guard.service.ts
callback.component.ts
global.events.manager.ts

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.

import { Injectable, Component, OnInit, OnDestroy } from '@angular/core';
import { Http, Headers, RequestOptions, Response } from '@angular/http';
import { Observable } from 'rxjs/Rx';
import { Subscription } from 'rxjs/Subscription';

import { OidcSecurityService, OpenIDImplicitFlowConfiguration } from 'angular-auth-oidc-client';

@Injectable()
export class AuthService implements OnInit, OnDestroy {
    isAuthorizedSubscription: Subscription;
    isAuthorized: boolean;

    constructor(public oidcSecurityService: OidcSecurityService,
        private http: Http) {

        const openIDImplicitFlowConfiguration = new OpenIDImplicitFlowConfiguration();
        openIDImplicitFlowConfiguration.stsServer = 'http://localhost:5000';

        openIDImplicitFlowConfiguration.redirect_url = 'http://localhost:5002/callback';
        // The Client MUST validate that the aud (audience) Claim contains its client_id value registered at the Issuer identified by the iss (issuer) Claim as an audience.
        // The ID Token MUST be rejected if the ID Token does not list the Client as a valid audience, or if it contains additional audiences not trusted by the Client.
        openIDImplicitFlowConfiguration.client_id = 'ng';
        openIDImplicitFlowConfiguration.response_type = 'id_token token';
        openIDImplicitFlowConfiguration.scope = 'openid profile apiApp';
        openIDImplicitFlowConfiguration.post_logout_redirect_uri = 'http://localhost:5002/home';
        openIDImplicitFlowConfiguration.start_checksession = true;
        openIDImplicitFlowConfiguration.silent_renew = true;
        openIDImplicitFlowConfiguration.startup_route = '/home';
        // HTTP 403
        openIDImplicitFlowConfiguration.forbidden_route = '/forbidden';
        // HTTP 401
        openIDImplicitFlowConfiguration.unauthorized_route = '/unauthorized';
        openIDImplicitFlowConfiguration.log_console_warning_active = true;
        openIDImplicitFlowConfiguration.log_console_debug_active = false;
        // id_token C8: The iat Claim can be used to reject tokens that were issued too far away from the current time,
        // limiting the amount of time that nonces need to be stored to prevent attacks.The acceptable range is Client specific.
        openIDImplicitFlowConfiguration.max_id_token_iat_offset_allowed_in_seconds = 10;

        this.oidcSecurityService.setupModule(openIDImplicitFlowConfiguration);
    }

    ngOnInit() {
        this.isAuthorizedSubscription = this.oidcSecurityService.getIsAuthorized().subscribe(
            (isAuthorized: boolean) => {
                this.isAuthorized = isAuthorized;
            });

        if (window.location.hash) {
            this.oidcSecurityService.authorizedCallback();
        }
    }

    ngOnDestroy(): void {
        this.isAuthorizedSubscription.unsubscribe();
    }

    authorizedCallback() {
        this.oidcSecurityService.authorizedCallback();
    }

    getIsAuthorized(): Observable<boolean> {
        return this.oidcSecurityService.getIsAuthorized();
    }

    login() {
        console.log('start login');
        this.oidcSecurityService.authorize();
    }

    logout() {
        console.log('start logoff');
        this.oidcSecurityService.logoff();
    }

    get(url: string, options?: RequestOptions): Observable<Response> {
        if (options) {
            options = this.setRequestOptions(options);
        }
        else {
            options = this.setRequestOptions();
        }
        return this.http.get(url, options);
    }

    private setRequestOptions(options?: RequestOptions) {
        if (options) {
            this.appendAuthHeader(options.headers);
        }
        else {
            options = new RequestOptions({ headers: this.getHeaders(), body: "" });
        }
        return options;
    }

    private getHeaders() {
        let headers = new Headers();
        headers.append('Content-Type', 'application/json');
        this.appendAuthHeader(headers);
        return headers;
    }

    private appendAuthHeader(headers: Headers) {       
        const token = this.oidcSecurityService.getToken();

        if (token == '') return;

        const tokenValue = 'Bearer ' + token;
        headers.append('Authorization', tokenValue);
    }
}

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.

Before:
import { Component } from '@angular/core';
import { AuthService } from '../services/auth.service'
import { GlobalEventsManager } from '../services/global.events.manager'

After:
import { Component, OnInit, OnDestroy } from '@angular/core';
import { Subscription } from 'rxjs/Subscription';
import { AuthService } from '../services/auth.service';

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.

export class NavMenuComponent implements OnInit, OnDestroy

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

ngOnInit() {
    this.isAuthorizedSubscription = 
            this.authService.getIsAuthorized().subscribe(
                   (isAuthorized: boolean) => {
                      this.isAuthorized = isAuthorized;
                    });

    if (window.location.hash) {
        this.authService.authorizedCallback();
    }
}

Then, ngOnDestroy handles the unsubscription.

ngOnDestroy(): void {
    this.isAuthorizedSubscription.unsubscribe();
}

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

isAuthorizedSubscription: Subscription;
isAuthorized: boolean;

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

constructor(public authService: AuthService) {
}

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

public login() {
    this.authService.login();
}

public logout() {
    this.authService.logout();
}

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.

Before:
<li *ngIf="!_loggedIn" [routerLinkActive]="['link-active']">
    <a (click)="login()" [routerLink]="['/login']">
        <span class="glyphicon glyphicon-user"></span> Login
    </a>
</li>

<li *ngIf="_loggedIn" [routerLinkActive]="['link-active']">
    <a (click)="logout()" [routerLink]="['/logout']">
        <span class='glyphicon glyphicon-log-out'></span> Logout
    </a>
</li>

After:
<li [routerLinkActive]="['link-active']">
    <a *ngIf="!isAuthorized" (click)="login()" [routerLink]="['/login']">
        <span class="glyphicon glyphicon-user"></span> Login
    </a>
</li>

<li [routerLinkActive]="['link-active']">
    <a *ngIf="isAuthorized" (click)="logout()">
        <span class='glyphicon glyphicon-log-out'></span> Logout</a>
</li>

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.

Before:
<a [routerLink]="['/fetch-data']">
    <span class='glyphicon glyphicon-th-list'></span> Fetch data
</a>

After:
<a *ngIf="isAuthorized" [routerLink]="['/fetch-data']">
    <span class='glyphicon glyphicon-th-list'></span> Fetch data
</a>

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.

Before:
authService.AuthGet(apiUrl + 'SampleData/WeatherForecasts').subscribe(result => {

After:
authService.get(apiUrl + 'SampleData/WeatherForecasts').subscribe(result => {

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: Redirect When Route Requires Logged in User

This post is going to continue where the series on IdentityServer4 left off, but I am not officially making it part of the series. There may be a few posts like this where I improve on the example applications from the series. The starting code for this post can be found here.

All the changes in the post are in the Client Application from the sample linked above. I did some cleanup on a couple of files so if you are looking for the differences keep in mind most of the changes are a result of the cleanup.

Unauthorized Component

The first step is to add a new component that will be shown to the user when they navigate to a page that requires them to be logged in but they are not. Add a unauthorized.component.html file to the ClientApp/app/components/unauthorized/ directory with the following contents.

<h2>
    Login is required to access this area
</h2>
<div>
    <button type="button" 
            class="btn btn-primary" 
            (click)="login()">Login</button>
    <button type="button" 
            class="btn btn-default" 
            (click)="goback()">Back</button>
</div>

This will tell the user they need to log in and provide a login button and a button to go back to the previous page. Next, add a unauthorized.component.ts file to the same directory. This class will handle the clicks from the view.

import { Component, OnInit } from '@angular/core';
import { Location } from '@angular/common';
import { AuthService } from '../services/auth.service';

@Component({
    selector: 'app-unauthorized',
    templateUrl: 'unauthorized.component.html'
})
export class UnauthorizedComponent implements OnInit {

    constructor(private location: Location, private service: AuthService) {

    }

    ngOnInit() {
    }

    login() {
        this.service.startSigninMainWindow();
    }

    goback() {
        this.location.back();
    }
}

This class is using the AuthService for login and Angular’s Location class to move back to the previous page.

New Component Usage

Now that this new component exists it needs to set up in app.module.shared.ts. First, add an import.

import { UnauthorizedComponent } from './components/unauthorized/unauthorized.component';

Next, add to the declarations array.

declarations: [
    AppComponent,
    NavMenuComponent,
    CounterComponent,
    FetchDataComponent,
    HomeComponent,
    CallbackComponent,
    UnauthorizedComponent
]

Finally, add unauthorized to the routes array.

RouterModule.forRoot([
    { path: '', redirectTo: 'home', pathMatch: 'full' },
    { path: 'home', component: HomeComponent },
    { path: 'callback', component: CallbackComponent },
    { path: 'unauthorized', component: UnauthorizedComponent },
    { path: 'counter', component: CounterComponent },
    { path: 'fetch-data', component: FetchDataComponent, 
                          canActivate:[AuthGuardService]  },
    { path: '**', redirectTo: 'home' }
])

Now that this new component is in place how does it get used? Well, any route that has canActivate:[AuthGuardService] will require the user to be logged in to activate. For example, the fetch-data route above won’t activate unless the user is logged in.

Auth Guard Service

AuthGuardService is an existing class in the project. The following is the full file.

import { Injectable, Component } from '@angular/core';
import { CanActivate, Router } from '@angular/router';

import { AuthService } from './auth.service';

@Injectable()
export class AuthGuardService implements CanActivate {

    constructor(private authService: AuthService, private router: Router) {
    }

    canActivate() {
        if (this.authService.loggedIn) {
            return true;
        }
        else {
            this.router.navigate(['unauthorized']);
        }
    }
}

As you can see in the canActivate function if the user is logged in then the function returns true otherwise, the user is routed to the unauthorized component. Before the changes in this post, this dropped the user back on the home page since the unauthorized component didn’t exist.

Wrapping up

With the changes above the user gets a slightly better experience. Just being dropped on the home page wasn’t very helpful as to why that was happening. This at least lets the user know they need to log in. Another option could be to hide the navigation for the routes they don’t have access to until they log it.

The finished version of the code 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.

using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;

namespace WebApplicationBasic.Controllers
{
    [Route("api/[controller]")]
    [Authorize]
    public class SampleDataController : Controller
    {
        private static string[] Summaries = new[]
        {
            "Freezing", "Bracing", "Chilly", "Cool", 
            "Mild", "Warm", "Balmy", "Hot", "Sweltering", "Scorching"
        };

        [HttpGet("[action]")]
        public IEnumerable<WeatherForecast> WeatherForecasts()
        {
            var rng = new Random();
            return Enumerable.Range(1, 5)
                             .Select(index => new WeatherForecast
            {
                DateFormatted = DateTime.Now.AddDays(index).ToString("d"),
                TemperatureC = rng.Next(-20, 55),
                Summary = Summaries[rng.Next(Summaries.Length)]
            });
        }

        public class WeatherForecast
        {
            public string DateFormatted { get; set; }
            public int TemperatureC { get; set; }
            public string Summary { get; set; }

            public int TemperatureF
            {
                get
                {
                    return 32 + (int)(TemperatureC / 0.5556);
                }
            }
        }
    }
}

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.

@NgModule({
    bootstrap: sharedConfig.bootstrap,
    declarations: sharedConfig.declarations,
    imports: [
        BrowserModule,
        FormsModule,
        HttpModule,
        ...sharedConfig.imports
    ],
    providers: [
        { provide: 'ORIGIN_URL', useValue: location.origin },
        { provide: 'API_URL', useValue: "http://localhost:5001/api/" },
        AuthService, AuthGuardService, GlobalEventsManager
    ]
})
export class AppModule {
}

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.

import { AuthService } from '../services/auth.service';

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.

Before:
constructor(http: Http, @Inject('ORIGIN_URL') originUrl: string)

After:
constructor(http: Http, @Inject('API_URL') apiUrl: string, authService: AuthService)

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

Before:
http.get(originUrl + 
         '/api/SampleData/WeatherForecasts').subscribe(result => {
    this.forecasts = result.json() as WeatherForecast[];
});

After:
authService.AuthGet(apiUrl + 
                    '/SampleData/WeatherForecasts').subscribe(result => {
    this.forecasts = result.json() as WeatherForecast[];
});

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.

AuthGet(url: string, options?: RequestOptions): Observable<Response> {
    if (options) {
      options = this._setRequestOptions(options);
    }
    else {
      options = this._setRequestOptions();
    }
    return this.http.get(url, options);
}

private _setAuthHeaders(user: User) {
    this._authHeaders = new Headers();
    this._authHeaders.append('Authorization', 
                             user.token_type + " " + user.access_token);
    this._authHeaders.append('Content-Type', 'application/json');
}

private _setRequestOptions(options?: RequestOptions) {
    if (options) {
      options.headers.append(this._authHeaders.keys[0],
                             this._authHeaders.values[0]);
    }
    else {
      //setting default authentication headers
      this._setAuthHeaders(this._currentUser);
      options = new RequestOptions({ headers: this._authHeaders, 
                                     body: "" });
    }
    return options;
}

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.