#27: Added UniqueAttribute.

Author: Marc Sallin

SQLite.CodeFirst/Attributes/OnConflictAction.cs

@@ -0,0 +1,16 @@
+namespace SQLite.CodeFirst
+{
+    /// <summary>
+    /// The action to resolve a UNIQUE constraint violation.
+    /// Is used together with the <see cref="UniqueAttribute"/>.
+    /// </summary>
+    public enum OnConflictAction
+    {
+        None,
+        Rollback,
+        Abort,
+        Fail,
+        Ignore,
+        Replace
+    }
+}

SQLite.CodeFirst/Attributes/UniqueAttribute.cs

@@ -0,0 +1,18 @@
+using System;
+
+namespace SQLite.CodeFirst
+{
+    /// <summary>
+    /// The UNIQUE Constraint prevents two records from having identical values in a particular column.
+    /// </summary>
+    [AttributeUsage(AttributeTargets.Property)]
+    public sealed class UniqueAttribute : Attribute
+    {
+        public UniqueAttribute(OnConflictAction onConflict = OnConflictAction.None)
+        {
+            OnConflict = onConflict;
+        }
+
+        public OnConflictAction OnConflict { get; set; }
+    }
+}

SQLite.CodeFirst/DbInitializers/SqliteInitializerBase.cs

@@ -3,6 +3,7 @@
 using System.Data.Entity.ModelConfiguration.Conventions;
 using SQLite.CodeFirst.Convention;
 using System.IO;
+using System.Linq;
 using SQLite.CodeFirst.Utility;
 
 namespace SQLite.CodeFirst
@@ -36,6 +37,10 @@ protected SqliteInitializerBase(DbModelBuilder modelBuilder)
             // See https://github.com/msallin/SQLiteCodeFirst/issues/7 for details.
             modelBuilder.Conventions.Remove<TimestampAttributeConvention>();
 
+            modelBuilder.Properties()
+                .Having(x => x.GetCustomAttributes(false).OfType<UniqueAttribute>().FirstOrDefault())
+                .Configure((config, attribute) => config.HasColumnAnnotation("IsUnique", attribute));
+
             // By default there is a 'ForeignKeyIndexConvention' but it can be removed.
             // And there is no "Contains" and no way to enumerate the ConventionsCollection.
             // So a try/catch will do the job.

SQLite.CodeFirst/SQLite.CodeFirst.csproj

@@ -83,6 +83,8 @@
     <Compile Include="..\Shared\AssemblySharedInfo.cs">
       <Link>Properties\AssemblySharedInfo.cs</Link>
     </Compile>
+    <Compile Include="Attributes\OnConflictAction.cs" />
+    <Compile Include="Attributes\UniqueAttribute.cs" />
     <Compile Include="Entities\IHistory.cs" />
     <Compile Include="Internal\Builder\NameCreators\IndexNameCreator.cs" />
     <Compile Include="Internal\Builder\NameCreators\SpecialChars.cs" />