Improved error messages when provider factory fails to create a migration provider.

Implemented full support for managed ODP.Net driver.

Author: Alex Henderson

src/Migrator.Providers/Impl/Oracle/OracleDialect.cs

@@ -5,7 +5,7 @@
 
 namespace Migrator.Providers.Oracle
 {
-	public class OracleDialect : Dialect
+    public class OracleDialect : Dialect
 	{
 		public OracleDialect()
 		{

src/Migrator.Providers/Impl/Oracle/OracleManagedDriverDialect.cs

@@ -0,0 +1,12 @@
+using Migrator.Framework;
+
+namespace Migrator.Providers.Oracle
+{
+    public class OracleManagedDriverDialect : OracleDialect
+    {
+        public override ITransformationProvider GetTransformationProvider(Dialect dialect, string connectionString, string defaultSchema)
+        {
+            return new OracleManagedDriverTransformationProvider(dialect, connectionString, defaultSchema);
+        }
+    }
+}

src/Migrator.Providers/Migrator.Providers-vs2010.csproj

@@ -103,6 +103,7 @@
     <Compile Include="ForeignKeyConstraintMapper.cs" />
     <Compile Include="Impl\Mysql\MysqlDialect.cs" />
     <Compile Include="Impl\Mysql\MySqlTransformationProvider.cs" />
+    <Compile Include="Impl\Oracle\OracleManagedDriverDialect.cs" />
     <Compile Include="Impl\Oracle\OracleColumnPropertiesMapper.cs" />
     <Compile Include="Impl\Oracle\OracleManagedDriverTransformationProvider.cs" />
     <Compile Include="Impl\PostgreSQL\PostgreSQL82Dialect.cs" />
@@ -121,6 +122,7 @@
     <Compile Include="TransformationProvider.cs" />
     <Compile Include="TypeNames.cs" />
     <Compile Include="Utility\MySqlServerUtility.cs" />
+    <Compile Include="Utility\OracleManagedDriverServerUtility.cs" />
     <Compile Include="Utility\OracleServerUtility.cs" />
     <Compile Include="Utility\PostgreSqlServerUtility.cs" />
     <Compile Include="Utility\SqlServerUtility.cs" />

src/Migrator.Providers/Utility/OracleManagedDriverServerUtility.cs

@@ -0,0 +1,97 @@
+using System;
+using System.Collections.Generic;
+using System.Data;
+using System.Linq;
+using Oracle.ManagedDataAccess.Client;
+
+namespace Migrator.Providers.Utility
+{
+    public static class OracleManagedDriverServerUtility
+    {
+        static readonly string[] _specialTableNames = new[]
+            {
+                "DEF$_AQCALL",
+                "DEF$_AQERROR",
+                "SQLPLUS_PRODUCT_PROFILE",
+                "HELP",
+                "MVIEW$_ADV_INDEX",
+                "MVIEW$_ADV_PARTITION"
+            };
+
+        public static void RemoveAllTablesFromDefaultDatabase(string connectionString)
+        {
+            using (var connection = new OracleConnection(connectionString))
+            {
+                connection.Open();
+
+                string[] allTablesToDrop = GetTablesToDrop(connection).ToArray();
+
+                foreach (string table in allTablesToDrop)
+                {
+                    string statement = string.Format("drop table \"{0}\" cascade constraints", table);
+
+                    ExecuteDropCommand(connection, statement);
+                }
+            }
+        }
+
+        static void ExecuteDropCommand(OracleConnection connection, string statement)
+        {
+            using (var dropCmd = new OracleCommand(statement, connection))
+            {
+                dropCmd.ExecuteNonQuery();
+            }
+        }
+
+        public static int GetTableCount(string connectionString)
+        {
+            using (var connection = new OracleConnection(connectionString))
+            {
+                connection.Open();
+
+                return GetTablesToDrop(connection).Count();
+            }
+        }
+
+        static string ExtractUserIDFromConnectionString(string connectionString)
+        {
+
+            string[] values = connectionString.Split(new[] { ";" }, StringSplitOptions.RemoveEmptyEntries);
+
+            var match = values.FirstOrDefault(v => v.StartsWith("User ID=", StringComparison.InvariantCultureIgnoreCase));
+
+            if (match != null)
+            {
+                string userName = match.Split(new[] { "=" }, StringSplitOptions.None)[1];
+                return userName;
+            }
+
+            return null;
+        }
+
+        public static IEnumerable<string> GetTablesToDrop(OracleConnection connection)
+        {
+            var schema = ExtractUserIDFromConnectionString(connection.ConnectionString);
+
+            string query = string.Format(@"select * from user_tables where TABLESPACE_NAME = '{0}'", schema);
+
+            using (var getDropAllTablesCommand = new OracleCommand(query, connection))
+            {
+                getDropAllTablesCommand.CommandType = CommandType.Text;
+
+                using (OracleDataReader reader = getDropAllTablesCommand.ExecuteReader())
+                {
+                    while (reader.Read() && (reader[0] != null && !Convert.IsDBNull(reader[0])))
+                    {
+                        string tableName = reader[0].ToString();
+
+                        if (!_specialTableNames.Contains(tableName))
+                        {
+                            yield return tableName;
+                        }
+                    }
+                }
+            }
+        }
+    }
+}

src/Migrator/ProviderFactory.cs

@@ -35,9 +35,17 @@ static ProviderFactory()
 
 		public static ITransformationProvider Create(string providerName, string connectionString, string defaultSchema)
 		{
-			Dialect dialectInstance = DialectForProvider(providerName);
+		    try
+		    {
+		        Dialect dialectInstance = DialectForProvider(providerName);
 
-			return dialectInstance.NewProviderForDialect(connectionString, defaultSchema);
+		        return dialectInstance.NewProviderForDialect(connectionString, defaultSchema);
+		    }
+		    catch (Exception ex)
+		    {
+		        throw new MigrationException(string.Format("Failed to create migration provider from arguments.\r\n  providerName: {0}\r\n  connectionString: {1}\r\n  defaultSchema: {2}\r\n\r\nError message was: {3}",
+                    providerName,connectionString,defaultSchema,ex.Message),ex);
+		    }
 		}
 
 		public static Dialect DialectForProvider(string providerName)