Refactor to prefer use of IMaskinportenSettings in ServiceCollectionE…

…xtensions (#21)

* Refactor DI extensions to use IMaskinportenSettings
* Update helpers and definitions
* Update samples and READMEs
* Minor fixes

README.md

@@ -18,34 +18,40 @@ You will need to configure a client definition, which is a way of providing the
 
 Here is an example with a both a [named](https://docs.microsoft.com/en-us/aspnet/core/fundamentals/http-requests?view=aspnetcore-6.0#named-clients) and [typed](https://docs.microsoft.com/en-us/aspnet/core/fundamentals/http-requests?view=aspnetcore-6.0#typed-clients) client using a client definition where the secret is a private RSA key in a JWK supplied in the injected settings.
 
-1. Client needs to configured in `ConfigureServices`, where `services` is a `IServiceCollection`
+1. Client needs to configured in `ConfigureServices`, where `services` is a `IServiceCollection`. Configuration settings for the client is provided as a instance of `MaskinportenSettings` (or any instance implementing `IMaskinportenSettings`). Alternatively, one can pass a `IConfiguration` instance to an overload that will bind this to a `MaskinportenSettings` instance.
 
 ```c#
+
+// We assume `Configuration` is a IConfiguration instance containing the settings from eg. appsettings.json.
+
+var maskinportenSettings = new MaskinportenSettings();
+Configuration.GetSection("MaskinportenSettings").Bind(maskinportenSettings);
+
 // Named client
-services.AddMaskinportenHttpClient<SettingsJwkClientDefinition>("myhttpclient",
-  Configuration.GetSection("MaskinportenSettings"));
+services.AddMaskinportenHttpClient<SettingsJwkClientDefinition>("myhttpclient", maskinportenSettings);
+
+// For convenience you can pass the IConfiguration instance directly
+// services.AddMaskinportenHttpClient<SettingsJwkClientDefinition>("myhttpclient", Configuration.GetSection("MaskinportenSettings"));
 
 // Typed client (MyMaskinportenHttpClient is any class accepting a HttpClient paramter in its constructor)
-services.AddMaskinportenHttpClient<SettingsJwkClientDefinition, MyMaskinportenHttpClient>(
-  Configuration.GetSection("MaskinportenSettings")); 
+services.AddMaskinportenHttpClient<SettingsJwkClientDefinition, MyMaskinportenHttpClient>(maskinportenSettings); 
 
 // Another typed client, using the same app settings, but overriding the setting for Altinn token exchange
 services.AddMaskinportenHttpClient<SettingsJwkClientDefinition, MyMaskinportenHttpClient>(
-  Configuration.GetSection("MaskinportenSettings"), clientDefinition =>
+  maskinportenSettings, clientDefinition =>
 {
     clientDefinition.ClientSettings.ExhangeToAltinnToken = true;
 });
 
 // You can chain additional handlers or configure the client if required 
-services.AddMaskinportenHttpClient<SettingsJwkClientDefinition, MyMaskinportenHttpClient>(
-  Configuration.GetSection("MaskinportenSettings"))
+services.AddMaskinportenHttpClient<SettingsJwkClientDefinition, MyMaskinportenHttpClient>(maskinportenSettings)
     .AddHttpMessageHandler(sp => ...)
     .ConfigureHttpClient(client => ...)
 
 // Registering av Maskinporten-powered client without adding it to HttpClientFactory / DIC
 services.RegisterMaskinportenClientDefinition<SettingsJwkClientDefinition>(
   "my-client-definition-instance-key",
-  Configuration.GetSection("MaskinportenSettings"));
+  maskinportenSettings);
 
 // This can then be added as a HttpMessageHandler to any IClientBuilder. This is
 // useful if you're already using a client builder (DAN, Polly, Refit etc).
@@ -119,7 +125,7 @@ public class MyController : ControllerBase
 
 <details><summary>See examples using the various client definition types</summary>
 
-Below are usage examples. Note that configuration binding (ie. `Configuration.GetSection("somesection")`) is omitted, as are the three mandatory settings that must always be supplied (Environment, ClientId, Scope)
+Below are usage examples. 
 
 ### SettingsJwk
 
@@ -175,6 +181,46 @@ services.AddMaskinportenHttpClient<Pkcs12ClientDefinition>( ... )
 ```
 </details>
 
+## Custom client definitions
+If you need to fetch the secret from some other source, you can provide your own implementation of `IClientDefinition` and pass it a custom `IMaskinportenSettings` instance containing any additional settings your source requires
+
+```c#
+// ---- MyExtendedMaskinportenSettings.cs ---- 
+public class MyExtendedMaskinportenSettings : MaskinportenSettings 
+{ // Extends MaskinportenSettings to avoid having to specify every field in IMaskinportenSettings
+    
+    public string MyCustomSetting { get; set; }
+}
+
+// ---- MyCustomClientDefinition.cs ---- 
+public class MyCustomClientDefinition : IClientDefinition
+{
+    public IMaskinportenSettings ClientSettings { get; set; }
+
+    // The custom client definitions are registered in the DIC as singletons
+    public MyCustomClientDefinition(ILogger<MyCustomClientDefinition> logger)
+    {
+        _logger = logger;
+    }
+
+    public async Task<ClientSecrets> GetClientSecrets()
+    {
+        var myExtendedSettings = (MyExtendedMaskinportenSettings)ClientSettings;
+        // use myExtendedSettings.MyCustomSetting
+        ...
+    }
+}
+
+// ---- Program.cs / Startup.cs ---- 
+var myExtendedMaskinportenSettings = new MyExtendedMaskinportenSettings();
+// We assume `Configuration` is a IConfiguration instance containing the settings from eg. appsettings.json
+// and that `services` is a IServiceCollection
+Configuration.GetSection("ExtendedMaskinportenSettings").Bind(myExtendedMaskinportenSettings);
+
+// Named client using a custom client definition and settings
+services.AddMaskinportenHttpClient<MyCustomClientDefinition>("myhttpclient", myExtendedMaskinportenSettings);
+```
+
 ## Using with Azure Keyvault as configuration provider i Azure App Services
 
 JWKs or certificates can be injected into application settings for Azure App Services or Azure Functions using [key vault references](https://docs.microsoft.com/en-us/azure/app-service/app-service-key-vault-references?tabs=azure-cli). This can then be easily used with the `SettingsJwk` or `SettingsX509` client definitions.

samples/SampleWebApp/Config/MyCustomClientDefinitionSettings.cs

@@ -1,8 +1,4 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Threading.Tasks;
-using Altinn.ApiClients.Maskinporten.Config;
+using Altinn.ApiClients.Maskinporten.Config;
 
 namespace SampleWebApp.Config
 {
@@ -11,4 +7,7 @@ public class MyCustomClientDefinitionSettings : MaskinportenSettings
         public string AzureKeyVaultName { get; set; }
         public string SecretName { get; set; }
     }
+
 }
+
+

samples/SampleWebApp/Controllers/MaskinportenTestController.cs

@@ -42,15 +42,15 @@ public async Task<string> Get()
             var client0 = _clientFactory.CreateClient("myhttpclient");
             var result0 = await client0.GetAsync(url + "?myhttpclient");
 
-            var client1 = _clientFactory.CreateClient("myotherhttpclient");
+            /*var client1 = _clientFactory.CreateClient("myotherhttpclient");
             var result1 = await client1.GetAsync(url + "?myotherhttpclient");
 
             // Perform some requests with both the named client and the type client. This will both use the same token. 
 
             var result2 = await _myMaskinportenHttpClient.PerformStuff(url + "?_myMaskinportenHttpClient");
             var result3 = await _myOtherMaskinportenHttpClient.PerformStuff(url + "?_myOtherMaskinportenHttpClient");
             var result4 = await _myThirdMaskinportenHttpClient.PerformStuff(url + "?_myThirdMaskinportenHttpClient");
-            var result5 = await _myFourthMaskinportenHttpClient.PerformStuff(url + "?_myFourthMaskinportenHttpClient");
+            var result5 = await _myFourthMaskinportenHttpClient.PerformStuff(url + "?_myFourthMaskinportenHttpClient");*/
 
             return "Done!";
         }

samples/SampleWebApp/MyCustomClientDefinition.cs

@@ -14,9 +14,7 @@ namespace SampleWebApp
     public class MyCustomClientDefinition : IClientDefinition
     {
         private readonly ILogger<MyCustomClientDefinition> _logger;
-        public MaskinportenSettings ClientSettings { get; set; }
-        public MyCustomClientDefinitionSettings MyCustomClientDefinitionSettings { get; set; } = new();
-
+        public IMaskinportenSettings ClientSettings { get; set; }
         private ClientSecrets _clientSecrets;
 
         public MyCustomClientDefinition(ILogger<MyCustomClientDefinition> logger)
@@ -32,13 +30,15 @@ public async Task<ClientSecrets> GetClientSecrets()
             }
 
             _logger.LogInformation("Getting secrets from Azure");
+
+            var myCustomClientDefinitionSettings = (MyCustomClientDefinitionSettings)ClientSettings;
 
             var secretClient = new SecretClient(
-                new Uri($"https://{MyCustomClientDefinitionSettings.AzureKeyVaultName}.vault.azure.net/"),
+                new Uri($"https://{myCustomClientDefinitionSettings.AzureKeyVaultName}.vault.azure.net/"),
                 new DefaultAzureCredential());
 
-            var secret = await secretClient.GetSecretAsync(MyCustomClientDefinitionSettings.SecretName);
-            var base64Str = secret.Value.ToString();
+            var secret = await secretClient.GetSecretAsync(myCustomClientDefinitionSettings.SecretName);
+            var base64Str = secret.HasValue ? secret.Value.Value : null;
             if (base64Str == null)
             {
                 throw new ApplicationException("Unable to fetch cert from key vault");

samples/SampleWebApp/Startup.cs

@@ -1,3 +1,4 @@
+using Altinn.ApiClients.Maskinporten.Config;
 using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.Extensions.Configuration;
@@ -6,6 +7,7 @@
 using Altinn.ApiClients.Maskinporten.Interfaces;
 using Altinn.ApiClients.Maskinporten.Services;
 using Altinn.ApiClients.Maskinporten.Extensions;
+using SampleWebApp.Config;
 
 namespace SampleWebApp
 {
@@ -31,53 +33,52 @@ public void ConfigureServices(IServiceCollection services)
             // will be used.
             services.AddSingleton<ITokenCacheProvider, FileTokenCacheProvider>();
 
+
             // Using a typed HttpClient is the preferred way of setting up a MaskinportenHttpClient;
-            services.AddMaskinportenHttpClient<SettingsJwkClientDefinition, MyMaskinportenHttpClient>(
-                Configuration.GetSection("MaskinportenSettingsForSomeExternalApi"));
-
+            var maskinportenSettingsForSomeExternalApi = new MaskinportenSettings();
+            Configuration.GetSection("MaskinportenSettingsForSomeExternalApi").Bind(maskinportenSettingsForSomeExternalApi);
+            services.AddMaskinportenHttpClient<SettingsJwkClientDefinition, MyMaskinportenHttpClient>(maskinportenSettingsForSomeExternalApi);
+
             // If you need to access multiple APIs requiring different settings (ie. scopes) you must supply a different 
             // typed client (may inherit a common base client)
-            services.AddMaskinportenHttpClient<SettingsJwkClientDefinition, MyOtherMaskinportenHttpClient>(
-                Configuration.GetSection("MaskinportenSettingsForSomeOtherExternalApi"));
+            var maskinportenSettingsForSomeOtherExternalApi = new MaskinportenSettings();
+            Configuration.GetSection("MaskinportenSettingsForSomeOtherExternalApi").Bind(maskinportenSettingsForSomeOtherExternalApi);
+            services.AddMaskinportenHttpClient<SettingsJwkClientDefinition, MyOtherMaskinportenHttpClient>(maskinportenSettingsForSomeOtherExternalApi);
 
             // You can reuse application settings for the across different HTTP clients, but override specific settings
             services.AddMaskinportenHttpClient<SettingsJwkClientDefinition, MyThirdMaskinportenHttpClient>(
-                Configuration.GetSection("MaskinportenSettingsForSomeOtherExternalApi"), clientDefinition =>
+                maskinportenSettingsForSomeOtherExternalApi, clientDefinition =>
                 {
                     clientDefinition.ClientSettings.ExhangeToAltinnToken = true;
                     clientDefinition.ClientSettings.Scope =
                         "altinn:serviceowner/instances.read altinn:serviceowner/instances.write";
                 });
 
             // As an alternative, named HTTP clients can be used. 
+            services.AddMaskinportenHttpClient<SettingsJwkClientDefinition>("myhttpclient", maskinportenSettingsForSomeExternalApi);
+
+            // Overloads are provided to send in a IConfiguration instance directly. This will be bound to an instance of MaskinportenSettings. 
             services.AddMaskinportenHttpClient<SettingsJwkClientDefinition>("myhttpclient", 
                 Configuration.GetSection("MaskinportenSettingsForSomeExternalApi"));
-
-            // You can also define your own client definitions:
-            services.AddMaskinportenHttpClient<MyCustomClientDefinition, MyFourthMaskinportenHttpClient>(
-                Configuration.GetSection("MyCustomClientDefinition"), clientDefinition =>
-                {
-                    // Any additional custom settings and/or fields in your custom client definition should be populated in the configureClientDefinition delegate
-                    clientDefinition.MyCustomClientDefinitionSettings = new MyCustomClientDefinitionSettings();
-                    Configuration.GetSection("MyCustomClientDefinition").Bind(clientDefinition.MyCustomClientDefinitionSettings);
-                });
+
+            // You can also define your own client definitions with custom settings, which should inherit MaskinportenSettings (or implement IMaskinportenSettings)
+            var myCustomClientDefinitionSettings = new MyCustomClientDefinitionSettings();
+            Configuration.GetSection("MyCustomClientDefinition").Bind(myCustomClientDefinitionSettings);
+            services.AddMaskinportenHttpClient<MyCustomClientDefinition, MyFourthMaskinportenHttpClient>(myCustomClientDefinitionSettings);
 
             // Named http clients for custom client definitions
-            services.AddMaskinportenHttpClient<MyCustomClientDefinition>("myotherhttpclient", Configuration.GetSection("MyCustomClientDefinition"), clientDefinition =>
-            {
-                Configuration.GetSection("MyCustomClientDefinition").Bind(clientDefinition.MyCustomClientDefinitionSettings);
-            });
+            services.AddMaskinportenHttpClient<MyCustomClientDefinition>("myotherhttpclient", myCustomClientDefinitionSettings);
 
             // You can chain additional handlers or configure the client further if you want
             /*
-            services.AddMaskinportenHttpClient<SettingsJwkClientDefinition, MyMaskinportenHttpClient>(Configuration.GetSection("MaskinportenSettingsForSomeExternalApi"))
+            services.AddMaskinportenHttpClient<SettingsJwkClientDefinition, MyMaskinportenHttpClient>(maskinportenSettingsForSomeExternalApi)
                 .AddHttpMessageHandler(sp => ...)
                 .ConfigureHttpClient(client => ...)
             */
 
             /*
             // Register a client definition and a configuration, identified by some arbitrary string key
-            services.RegisterMaskinportenClientDefinition<SettingsJwkClientDefinition>("my-client-definition-key", Configuration.GetSection("MaskinportenSettingsForSomeExternalApi"));
+            services.RegisterMaskinportenClientDefinition<SettingsJwkClientDefinition>("my-client-definition-key", maskinportenSettingsForSomeExternalApi);
 
             // This can then be added as a HttpMessageHandler to any IClientBuilder (if also using DAN, Polly, Refit etc)
             services.AddHttpClient<MyMaskinportenHttpClient>()

src/Altinn.ApiClients.Maskinporten/Config/MaskinportenSettings.cs

@@ -2,7 +2,7 @@
 
 namespace Altinn.ApiClients.Maskinporten.Config
 {
-    public class MaskinportenSettings
+    public class MaskinportenSettings : IMaskinportenSettings
     {
         /// <summary>
         /// ClientID to use