ConnectionInfoParser: supports connection strings as dictionary

Author: alex-kulakov

Orm/Xtensive.Orm/Orm/Configuration/Internals/ConnectionInfoParser.cs

@@ -5,17 +5,61 @@
 // Created:    2013.09.27
 
 using System;
+using System.Collections;
+using System.Collections.Generic;
 using System.Configuration;
+using System.Diagnostics.CodeAnalysis;
+using Microsoft.Extensions.Configuration;
 using Xtensive.Core;
 
 namespace Xtensive.Orm.Configuration
 {
   internal static class ConnectionInfoParser
   {
+    private readonly struct UnifiedAccessor
+    {
+      private readonly IDictionary<string, string> connectionStringsAsDict;
+      private readonly ConnectionStringSettingsCollection connectionStrings;
+
+      public string this[string key] {
+        get {
+          if (connectionStrings != null)
+            return connectionStrings[key]?.ConnectionString;
+          else if(connectionStringsAsDict!=null)
+            return connectionStringsAsDict[key];
+          return null;
+        }
+      }
+
+      public UnifiedAccessor(ConnectionStringSettingsCollection oldConnectionStrings)
+      {
+        connectionStringsAsDict = null;
+        connectionStrings = oldConnectionStrings;
+      }
+      public UnifiedAccessor(IDictionary<string, string> connectionStrings)
+      {
+        connectionStringsAsDict = connectionStrings;
+        this.connectionStrings = null;
+      }
+    }
+
     public static ConnectionInfo GetConnectionInfo(System.Configuration.Configuration configuration,string connectionUrl, string provider, string connectionString)
     {
-      bool connectionUrlSpecified = !string.IsNullOrEmpty(connectionUrl);
-      bool connectionStringSpecified = !string.IsNullOrEmpty(connectionString) && !string.IsNullOrEmpty(provider);
+      var accessor = new UnifiedAccessor(configuration.ConnectionStrings.ConnectionStrings);
+      return GetConnectionInfoInternal(accessor, connectionUrl, provider, connectionString);
+    }
+
+    public static ConnectionInfo GetConnectionInfo(IDictionary<string,string> connectionStrings, string connectionUrl, string provider, string connectionString)
+    {
+      var accessor = new UnifiedAccessor(connectionStrings);
+      return GetConnectionInfoInternal(accessor, connectionUrl, provider, connectionString);
+    }
+
+    private static ConnectionInfo GetConnectionInfoInternal(in UnifiedAccessor connectionStringAccessor,
+      string connectionUrl, string provider, string connectionString)
+    {
+      var connectionUrlSpecified = !string.IsNullOrEmpty(connectionUrl);
+      var connectionStringSpecified = !string.IsNullOrEmpty(connectionString) && !string.IsNullOrEmpty(provider);
 
       if (connectionUrlSpecified && connectionStringSpecified)
         throw new InvalidOperationException(Strings.ExConnectionInfoIsWrongYouShouldSetEitherConnectionUrlElementOrProviderAndConnectionStringElements);
@@ -24,30 +68,31 @@ public static ConnectionInfo GetConnectionInfo(System.Configuration.Configuratio
         return new ConnectionInfo(connectionUrl);
 
       if (connectionStringSpecified)
-        return new ConnectionInfo(provider, ExpandConnectionString(configuration, connectionString));
+        return new ConnectionInfo(provider,
+          ExpandConnectionString(connectionStringAccessor, connectionString));
 
       // Neither connection string, nor connection url specified.
       // Leave connection information undefined.
       return null;
     }
 
-    private static string ExpandConnectionString(System.Configuration.Configuration configuration, string connectionString)
+    private static string ExpandConnectionString(in UnifiedAccessor connectionStrings, string connectionString)
     {
       const string prefix = "#";
 
       if (!connectionString.StartsWith(prefix, StringComparison.Ordinal))
         return connectionString;
 
-      string connectionStringName = connectionString.Substring(prefix.Length);
+      var connectionStringName = connectionString[prefix.Length..];
 
-      var connectionStringSetting = configuration.ConnectionStrings.ConnectionStrings[connectionStringName];
-      if (connectionStringSetting==null)
+      var connectionStringSetting = connectionStrings[connectionStringName];
+      if (connectionStringSetting == null)
         throw new InvalidOperationException(string.Format(Strings.ExConnectionStringWithNameXIsNotFound, connectionStringName));
 
-      if (string.IsNullOrEmpty(connectionStringSetting.ConnectionString))
+      if (string.IsNullOrEmpty(connectionStringSetting))
         throw new InvalidOperationException(string.Format(Strings.ExConnectionStringWithNameXIsNullOrEmpty, connectionStringName));
 
-      return connectionStringSetting.ConnectionString;
+      return connectionStringSetting;
     }
   }
 }