MS Dependency Injection update

* Switch to Singleton AutoSolrConnection
* Add override to IServiceCollection.AddSolrNet , allowing to set injection options. Currently only supporting tweaking the HttpClient in use by the AutoSolrConnection.
* Add unit test showing the use of Basic Authentication.

Fixes SolrNet#402

Microsoft.DependencyInjection.SolrNet.Tests/MicrosoftDependencyFixture.cs

@@ -74,10 +74,10 @@ public void ResolveSolrAbstractResponseParser()
         public void CannotResolveSolrAbstractResponseParsersViaArray()
         {
             //MS Dependency injection doesn't support 
-            Assert.Throws<InvalidOperationException>(() => 
+            Assert.Throws<InvalidOperationException>(() =>
                 DefaultServiceProvider.GetRequiredService<ISolrAbstractResponseParser<Entity>[]>()
             );
-            
+
         }
 
 
@@ -107,6 +107,27 @@ public void ResolveSolrOperations()
         }
 
 
+
+        [Fact]
+        public void SetBasicAuthenticationHeader()
+        {
+            var sc = new ServiceCollection();
+
+            //my credentials
+            var credentials = System.Text.Encoding.ASCII.GetBytes("myUsername:myPassword");
+            //in base64
+            var credentialsBase64 = Convert.ToBase64String(credentials);
+            //use the options to set the Authorization header.
+            sc.AddSolrNet("http://localhost:8983/solr", options => { options.HttpClient.DefaultRequestHeaders.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Basic", credentialsBase64); });
+
+            //test
+            var provider = sc.BuildServiceProvider();
+            var connection = provider.GetRequiredService<ISolrConnection>() as AutoSolrConnection;
+
+            Assert.NotNull(connection.HttpClient.DefaultRequestHeaders.Authorization);
+            Assert.Equal(credentialsBase64, connection.HttpClient.DefaultRequestHeaders.Authorization.Parameter);
+        }
+
         public class Entity { }
     }
 }

Microsoft.DependencyInjection.SolrNet/ServiceCollectionExtensions.cs

@@ -22,10 +22,12 @@ public static IServiceCollection AddSolrNet(this IServiceCollection services, st
         {
             if (services == null) throw new ArgumentNullException(nameof(services));
 
-            return services.AddSolrNet(new SolrCore[] { new SolrCore(null, null, url) });
+            return services.AddSolrNet(new SolrCore[] { new SolrCore(null, null, url) }, null);
         }
 
-        private static IServiceCollection AddSolrNet(this IServiceCollection services, IEnumerable<SolrCore> cores)
+        public static IServiceCollection AddSolrNet(this IServiceCollection services, string url, Action<SolrNetOptions> setupAction) => AddSolrNet(services, new SolrCore[] { new SolrCore(null, null, url) }, setupAction);
+
+        private static IServiceCollection AddSolrNet(this IServiceCollection services, IEnumerable<SolrCore> cores, Action<SolrNetOptions> setupAction)
         {
             if (services == null) throw new ArgumentNullException(nameof(services));
 
@@ -34,7 +36,7 @@ private static IServiceCollection AddSolrNet(this IServiceCollection services, I
             services.AddTransient<ISolrFieldParser, DefaultFieldParser>();
             services.AddTransient(typeof(ISolrDocumentActivator<>), typeof(SolrDocumentActivator<>));
             services.AddTransient(typeof(ISolrDocumentResponseParser<>), typeof(SolrDocumentResponseParser<>));
-            
+
             services.AddTransient<ISolrDocumentResponseParser<Dictionary<string, object>>, SolrDictionaryDocumentResponseParser>();
             services.AddTransient<ISolrFieldSerializer, DefaultFieldSerializer>();
             services.AddTransient<ISolrQuerySerializer, DefaultQuerySerializer>();
@@ -63,15 +65,22 @@ private static IServiceCollection AddSolrNet(this IServiceCollection services, I
             {
                 throw new NotImplementedException("Microsoft DependencyInjection doesn't support Key/Name based injection. This is a place holder for the future.");
             }
-            else
+
+            var connection = new AutoSolrConnection(cores.Single().Url);
+            //Bind single type to a single url, prevent breaking existing functionality
+            services.AddSingleton<ISolrConnection>(connection);
+            services.AddTransient(typeof(ISolrQueryExecuter<>), typeof(SolrQueryExecuter<>));
+            services.AddTransient(typeof(ISolrBasicOperations<>), typeof(SolrBasicServer<>));
+            services.AddTransient(typeof(ISolrBasicReadOnlyOperations<>), typeof(SolrBasicServer<>));
+            services.AddScoped(typeof(ISolrOperations<>), typeof(SolrServer<>));
+            services.AddTransient(typeof(ISolrReadOnlyOperations<>), typeof(SolrServer<>));
+
+
+            if (setupAction != null)
             {
-                //Bind single type to a single url, prevent breaking existing functionality
-                services.AddTransient<ISolrConnection>(_ => new SolrConnection(cores.Single().Url));
-                services.AddTransient(typeof(ISolrQueryExecuter<>), typeof(SolrQueryExecuter<>));
-                services.AddTransient(typeof(ISolrBasicOperations<>), typeof(SolrBasicServer<>));
-                services.AddTransient(typeof(ISolrBasicReadOnlyOperations<>), typeof(SolrBasicServer<>));
-                services.AddScoped(typeof(ISolrOperations<>), typeof(SolrServer<>));
-                services.AddTransient(typeof(ISolrReadOnlyOperations<>), typeof(SolrServer<>));
+                var options = new SolrNetOptions(connection.HttpClient);
+                //allow for custom headers to be injected.
+                setupAction(options);
             }
 
 

Microsoft.DependencyInjection.SolrNet/SolrNetOptions.cs

@@ -0,0 +1,17 @@
+using System.Net.Http;
+
+namespace SolrNet
+{
+    public class SolrNetOptions
+    {
+        public SolrNetOptions(HttpClient httpClient)
+        {
+            HttpClient = httpClient;
+        }
+
+        /// <summary>
+        /// Gets the HttpClient with which SolrNet connects to the Solr server. This is the place to add Default Headers for Basic Authentication for example..
+        /// </summary>
+        public HttpClient HttpClient { get; }
+    }
+}