Refactor - extract interface for db handling

To assist with multi-db support

issue #16

EfEnumToLookup/EfEnumToLookup.csproj

@@ -56,6 +56,7 @@
   <ItemGroup>
     <Compile Include="LookupGenerator\EnumGeneratorException.cs" />
     <Compile Include="LookupGenerator\EnumToLookup.cs" />
+    <Compile Include="LookupGenerator\IDbHandler.cs" />
     <Compile Include="LookupGenerator\IEnumToLookup.cs" />
     <Compile Include="LookupGenerator\EnumReference.cs" />
     <Compile Include="LookupGenerator\LookupData.cs" />

EfEnumToLookup/LookupGenerator/EnumToLookup.cs

@@ -71,20 +71,9 @@ public void Apply(DbContext context)
 			// recurse through dbsets and references finding anything that uses an enum
 			var enumReferences = FindEnumReferences(context);
 
-			var sqlServerHandler = new SqlServerHandler
-			{
-				NameFieldLength = NameFieldLength,
-				TableNamePrefix = TableNamePrefix,
-				TableNameSuffix = TableNameSuffix,
-			};
-
-			// todo: fold the populate method into the create tables method, providing all the data to the db layer in one hit,
-			//  this will require merging the two sql callbacks into one signature
-
 			// for the list of enums generate and missing tables
 			var enums = enumReferences.Select(r => r.EnumType).Distinct().ToList();
 
-			// merge values into these tables
 			var lookups =
 				(from enm in enums
 				select new LookupData
@@ -93,7 +82,13 @@ public void Apply(DbContext context)
 					Values = GetLookupValues(enm),
 				}).ToList();
 
-			sqlServerHandler.Apply(lookups, enumReferences, (sql, parameters) => ExecuteSqlCommand(context, sql, parameters));
+			// todo: support MariaDb etc. Issue #16
+			IDbHandler dbHandler = new SqlServerHandler();
+			dbHandler.NameFieldLength = NameFieldLength;
+			dbHandler.TableNamePrefix = TableNamePrefix;
+			dbHandler.TableNameSuffix = TableNameSuffix;
+
+			dbHandler.Apply(lookups, enumReferences, (sql, parameters) => ExecuteSqlCommand(context, sql, parameters));
 		}
 
 		private static int ExecuteSqlCommand(DbContext context, string sql, IEnumerable<SqlParameter> parameters = null)

EfEnumToLookup/LookupGenerator/IDbHandler.cs

@@ -0,0 +1,29 @@
+namespace EfEnumToLookup.LookupGenerator
+{
+	using System;
+	using System.Collections.Generic;
+	using System.Data.SqlClient;
+
+	internal interface IDbHandler
+	{
+		/// <summary>
+		/// The size of the Name field that will be added to the generated lookup tables.
+		/// Adjust to suit your data if required.
+		/// </summary>
+		int NameFieldLength { get; set; }
+
+		/// <summary>
+		/// Prefix to add to all the generated tables to separate help group them together
+		/// and make them stand out as different from other tables.
+		/// </summary>
+		string TableNamePrefix { get; set; }
+
+		/// <summary>
+		/// Suffix to add to all the generated tables to separate help group them together
+		/// and make them stand out as different from other tables.
+		/// </summary>
+		string TableNameSuffix { get; set; }
+
+		void Apply(List<LookupData> lookups, IList<EnumReference> enumReferences, Action<string, IEnumerable<SqlParameter>> runSql);
+	}
+}

EfEnumToLookup/LookupGenerator/SqlServerHandler.cs

@@ -5,7 +5,7 @@
 	using System.Data.SqlClient;
 	using System.Text;
 
-	class SqlServerHandler
+	class SqlServerHandler : IDbHandler
 	{
 		/// <summary>
 		/// The size of the Name field that will be added to the generated lookup tables.
@@ -28,7 +28,7 @@ class SqlServerHandler
 		public string TableNameSuffix { get; set; }
 
 
-		internal void Apply(List<LookupData> lookups, IList<EnumReference> enumReferences, Action<string, IEnumerable<SqlParameter>> runSql)
+		public void Apply(List<LookupData> lookups, IList<EnumReference> enumReferences, Action<string, IEnumerable<SqlParameter>> runSql)
 		{
 			CreateTables(lookups, (sql) => runSql(sql, null));
 			PopulateLookups(lookups, runSql);