Merge pull request #4 from dpaquette/ExceptionHandling

Exception handling

src/EntityFramework.Seeder.EF6.Tests/CountriesFileWithErrors.csv

@@ -0,0 +1,5 @@
+CodeNotRight,NameAlsoNotRight
+AT,Austria
+AU,Australia
+CA,Canada
+US,United States

src/EntityFramework.Seeder.EF6.Tests/EntityFramework.Seeder.EF6.Tests.csproj

@@ -79,6 +79,7 @@
     <Compile Include="Domain\Country.cs" />
     <Compile Include="Domain\CountryContext.cs" />
     <Compile Include="Domain\ProvinceState.cs" />
+    <Compile Include="when_an_error_occurs_while_seeding_a_dbset.cs" />
     <Compile Include="when_seeding_an_empty_db_set_from_a_file.cs" />
     <Compile Include="when_seeding_an_empty_db_set_from_a_resource.cs" />
     <Compile Include="when_seeding_a_dbset_with_related_entites.cs" />
@@ -98,6 +99,9 @@
       <CopyToOutputDirectory>Always</CopyToOutputDirectory>
     </Content>
     <EmbeddedResource Include="ProvinceStatesResource.csv" />
+    <Content Include="CountriesFileWithErrors.csv">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </Content>
     <None Include="packages.config" />
   </ItemGroup>
   <ItemGroup>

src/EntityFramework.Seeder.EF6.Tests/when_an_error_occurs_while_seeding_a_dbset.cs

@@ -0,0 +1,74 @@
+using System;
+using System.IO;
+using System.Linq;
+using System.Runtime.Serialization.Formatters.Binary;
+using EntityFramework.Seeder.EF6.Tests.Domain;
+using Given.Common;
+using Given.NUnit;
+using NUnit.Framework;
+
+namespace EntityFramework.Seeder.EF6.Tests
+{
+    [Story(AsA = "developer",
+        IWant = "see exception details",
+        SoThat = "I can diagnose errors that might happen while seeding a dbset")]
+    public class while_an_error_occurs_while_seeding_a_dbset : Scenario
+    {
+        public static CountryContext _context;
+
+        given an_empty_context = () =>
+        {
+            _context = new CountryContext();
+            _context.DeleteAll();
+        };
+
+
+        [then]
+        [ExpectedException(typeof(Exception))]
+        public void when_seeding_from_a_file_with_unmapped_columns()
+        {
+            _context.Countries.SeedFromFile("CountriesFileWithErrors.csv", c => c.Code);
+        }
+
+        [then]
+        public void the_exception_should_be_serializable()
+        {
+            Exception exception = null;
+            try
+            {
+                _context.Countries.SeedFromFile("CountriesFileWithErrors.csv", c => c.Code);
+            }
+            catch (Exception ex)
+            {
+                exception = ex;
+            }
+
+            Assert.IsNotNull(exception);
+
+            string exceptionToString = exception.ToString();
+
+            // Round-trip the exception: Serialize and de-serialize with a BinaryFormatter
+            BinaryFormatter bf = new BinaryFormatter();
+            using (MemoryStream ms = new MemoryStream())
+            {
+                // "Save" object state
+                bf.Serialize(ms, exception);
+
+                // Re-use the same stream for de-serialization
+                ms.Seek(0, 0);
+
+                // Replace the original exception with de-serialized one
+                exception = (Exception)bf.Deserialize(ms);
+            }
+
+            // Double-check that the exception message and stack trace (owned by the base Exception) are preserved
+            Assert.AreEqual(exceptionToString, exception.ToString(), "ex.ToString()");
+        }
+
+        [TestFixtureTearDown]
+        public void TearDown()
+        {
+            _context.Dispose();
+        }
+    }
+}

src/EntityFramework.Seeder.EF6/EFSeederException.cs

@@ -0,0 +1,34 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Runtime.Serialization;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace EntityFramework.Seeder
+{
+    /// <summary>
+    /// Represents an exception that has occurred while seeding a dbset.
+    /// Wraps the underlying exception and is serializable so that the exception message can be
+    ///   properly displayed in the package manager console in Visual Studio
+    /// </summary>
+    [Serializable]
+    public class EfSeederException : Exception, ISerializable
+    {
+        public EfSeederException()
+        {
+        }
+
+        public EfSeederException(string message) : base(message)
+        {
+        }
+
+        public EfSeederException(string message, Exception innerException) : base(message, innerException)
+        {
+        }
+
+        protected EfSeederException(SerializationInfo info, StreamingContext context) : base(info, context)
+        {
+        }
+    }
+}

src/EntityFramework.Seeder.EF6/EntityFramework.Seeder.EF6.csproj

@@ -52,6 +52,7 @@
   </ItemGroup>
   <ItemGroup>
     <Compile Include="CsvColumnMapping.cs" />
+    <Compile Include="EFSeederException.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="Seeder.cs" />
   </ItemGroup>

src/EntityFramework.Seeder.EF6/Properties/AssemblyInfo.cs

@@ -10,7 +10,7 @@
 [assembly: AssemblyConfiguration("")]
 [assembly: AssemblyCompany("")]
 [assembly: AssemblyProduct("EntityFramework.Seeder")]
-[assembly: AssemblyCopyright("Copyright ©  2014")]
+[assembly: AssemblyCopyright("Copyright ©  2015")]
 [assembly: AssemblyTrademark("")]
 [assembly: AssemblyCulture("")]
 
@@ -32,5 +32,5 @@
 // You can specify all the values or you can default the Build and Revision Numbers 
 // by using the '*' as shown below:
 // [assembly: AssemblyVersion("1.0.*")]
-[assembly: AssemblyVersion("0.2.1.0")]
-[assembly: AssemblyFileVersion("0.2.1.0")]
+[assembly: AssemblyVersion("0.3.2.0")]
+[assembly: AssemblyFileVersion("0.3.2.0")]

src/EntityFramework.Seeder.EF6/Seeder.cs

@@ -13,6 +13,22 @@ namespace EntityFramework.Seeder
     /// </summary>
     public static class Seeder
     {
+        static Seeder()
+        {
+            AppDomain.CurrentDomain.AssemblyResolve += ResolveAssembly;
+        }
+
+        private static Assembly ResolveAssembly(object sender, ResolveEventArgs args)
+        {
+            if (new AssemblyName(args.Name).Name == "EntityFramework.Seeder.EF6")
+            {
+                return typeof (Seeder).Assembly;
+            }
+
+            return null;
+
+        }
+
         /// <summary>
         /// Seeds a DBSet from a CSV file that will be read from the specified stream
         /// </summary>
@@ -23,23 +39,33 @@ public static class Seeder
         /// <param name="additionalMapping">Any additonal complex mappings required</param>
         public static void SeedFromStream<T>(this IDbSet<T> dbSet, Stream stream, Expression<Func<T, object>> identifierExpression, params CsvColumnMapping<T>[] additionalMapping) where T : class
         {
-            using (StreamReader reader = new StreamReader(stream))
+            try
             {
-                CsvReader csvReader = new CsvReader(reader);
-                var map = csvReader.Configuration.AutoMap<T>();
-                map.ReferenceMaps.Clear();
-                csvReader.Configuration.RegisterClassMap(map);
-                csvReader.Configuration.WillThrowOnMissingField = false;
-                while (csvReader.Read())
+                using (StreamReader reader = new StreamReader(stream))
                 {
-                    var entity= csvReader.GetRecord<T>();
-                    foreach (CsvColumnMapping<T> csvColumnMapping in additionalMapping)
+                    CsvReader csvReader = new CsvReader(reader);
+                    var map = csvReader.Configuration.AutoMap<T>();
+                    map.ReferenceMaps.Clear();
+                    csvReader.Configuration.RegisterClassMap(map);
+                    csvReader.Configuration.WillThrowOnMissingField = false;
+                    while (csvReader.Read())
                     {
-                        csvColumnMapping.Execute(entity, csvReader.GetField(csvColumnMapping.CsvColumnName));
+                        var entity = csvReader.GetRecord<T>();
+                        foreach (CsvColumnMapping<T> csvColumnMapping in additionalMapping)
+                        {
+                            csvColumnMapping.Execute(entity, csvReader.GetField(csvColumnMapping.CsvColumnName));
+                        }
+                        dbSet.AddOrUpdate(identifierExpression, entity);
                     }
-                    dbSet.AddOrUpdate(identifierExpression, entity);
                 }
             }
+            catch (Exception ex)
+            {
+                string message = string.Format("Error Seeding DbSet<{0}>: {1}", dbSet.GetType().GenericTypeArguments[0].FullName, ex.ToString());
+                Exception innerException = ex.GetType().IsSerializable ? ex : null;
+                //Unfortunately I need to use a root exception here as this is the only way for the Update-Database powershell script to properly report the error
+                throw new Exception(message, innerException);                
+            }
         }
 
         /// <summary>