Refactored IMetadataService to be async and removed init-related methods (#266)

* Refactored IMetadataService and implemented a new "on demand" implementation of DistributedCacheMetadataService that uses a combination of in-memory and distributed cache implementations

* Renamed SimpleMetadataService to ConformanceMetadataService since that's now its only purpose

* Updated Fido2MetadataServiceRepository to use IHttpClientFactory and a named client rather than using the typed client registration mechanism

* Changed the origin

Co-authored-by: Anders Åberg <anders@andersaberg.com>

Author: mackie1001

Demo/ConformanceTesting.cs

@@ -22,8 +22,9 @@ public static IMetadataService MetadataServiceInstance(string cacheDir, string o
                             new ConformanceMetadataRepository(null, origin),
                             new FileSystemMetadataRepository(cacheDir)
                         };
-                        _instance = new SimpleMetadataService(repos);
-                        _instance.InitializeAsync().Wait();
+                        var simpleService = new ConformanceMetadataService(repos);
+                        simpleService.InitializeAsync().Wait();
+                        _instance = simpleService;
                     }
                 }
             }

Demo/Pages/dashboard.cshtml

@@ -51,7 +51,7 @@
 
                     if (_mds != null)
                     {
-                        var entry = _mds.GetEntry(item.AaGuid);
+                        var entry = await _mds.GetEntryAsync(item.AaGuid);
                         desc = entry.MetadataStatement.Description.ToString();
                         icon = entry.MetadataStatement.Icon.ToString();
                     }

Demo/Startup.cs

@@ -30,7 +30,9 @@ public void ConfigureServices(IServiceCollection services)
             });
 
             // Use the in-memory implementation of IDistributedCache.
+            services.AddMemoryCache();
             services.AddDistributedMemoryCache();
+
             services.AddSession(options =>
             {
                 // Set a short timeout for easy testing.
@@ -52,7 +54,10 @@ public void ConfigureServices(IServiceCollection services)
             })
             .AddCachedMetadataService(config =>
             {
-                config.AddFidoMetadataRepository();
+                config.AddFidoMetadataRepository(httpClientBuilder =>
+                {
+                    //TODO: any specific config you want for accessing the MDS
+                });
             });
         }
 

Demo/appsettings.json

@@ -2,7 +2,7 @@
   "fido2": {
     "serverDomain": "localhost",
     "origin": "https://localhost:44329",
-    "timestampDriftTolerance": 300000,
+    "timestampDriftTolerance": 300000
   },  
   "Logging": {
     "IncludeScopes": false,

Src/Fido2.AspNet/DateTimeUtilities.cs

@@ -0,0 +1,35 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Fido2NetLib
+{
+    internal static class DateTimeUtilities
+    {
+        /// <summary>
+        /// Finds the nearest future point in time that aligns with the increment provided
+        /// e.g. 12:58:23 -> 13:00 if the increment provided is 2 minutes
+        /// </summary>
+        /// <param name="startTime">The time from which to calculated the next increment</param>
+        /// <param name="increment">The increment used to calculate the new time</param>
+        /// <returns></returns>
+        public static DateTimeOffset GetNextIncrement(this DateTimeOffset startTime, TimeSpan increment)
+        {
+            //Find next increment
+            var nextIncrementTicks = (long)(Math.Ceiling((decimal)startTime.Ticks / (decimal)increment.Ticks) * (decimal)increment.Ticks);
+
+            //Find the difference between the start time and the target time
+            var timeSpanDiff = TimeSpan.FromTicks(nextIncrementTicks).Subtract(TimeSpan.FromTicks(startTime.Ticks));
+
+            //If the calculated difference is 0 then make it the increment value
+            if (timeSpanDiff.Ticks == 0)
+                timeSpanDiff = TimeSpan.FromTicks(increment.Ticks);
+
+            //Add the difference to the normalised time
+            return startTime.Add(timeSpanDiff);
+        }
+
+    }
+}