Merge pull request #38 from absynce/custom-migration-attributes

Custom migration attributes

CHANGELOG.md

@@ -10,6 +10,8 @@ changes. This project adheres to [Semantic Versioning](http://semver.org).
   versions of Raven ignore multiple separators and others do not. This change
   could cause migrations to be run multiple times in some cases if the ids are not
   changed first.
+- Added - Ability to inherit from `MigrationAttribute` to specify custom migration
+  versions.
 
 ## [1.2.0]
 - Added new way to change a collection with

RavenMigrations.Tests/RunnerTests.cs

@@ -266,6 +266,24 @@ public void Can_call_migrations_that_are_not_direct_subclasses_of_Migration()
                 }
             }
         }
+
+        [Fact]
+        public void Can_call_migrations_with_custom_attributes()
+        {
+            using (var store = NewDocumentStore())
+            {
+                new TestDocumentIndex().Execute(store);
+
+                Runner.Run(store);
+                WaitForIndexing(store);
+
+                using (var session = store.OpenSession())
+                {
+                    var customMigration = session.Load<object>("migrated-using-custom-migration-attribute");
+                    customMigration.Should().NotBeNull();
+                }
+            }
+        }
     }
 
     public class TestDocument
@@ -359,10 +377,37 @@ public override void Up()
         }
     }    
 
+    [MigrationVersion(6, 0, 0, 0)]
+    public class Uses_Custom_Migration_Attribute : Migration
+    {
+        public override void Up()
+        {
+            using (var session = DocumentStore.OpenSession())
+            {
+                session.Store(new { Id = "migrated-using-custom-migration-attribute" });
+                session.SaveChanges();
+            }
+        }
+    }    
+
     public abstract class BaseMigration : Migration
     {
         public override void Up()
         {
         }
     }
+
+    public class MigrationVersionAttribute : MigrationAttribute
+    {
+        public MigrationVersionAttribute(int major, int minor, int patch, int migration, params string [] profiles)
+            :base(CreateVersionNumber(major, minor, patch, migration), profiles)
+        {
+
+        }
+
+        private static long CreateVersionNumber(int major, int minor, int patch, int migration)
+        {
+            return major*1000000000000L + minor*100000000L + patch*1000000L + migration;
+        }
+    }
 }

RavenMigrations/RavenMigrationHelpers.cs

@@ -29,7 +29,7 @@ public static string GetMigrationIdFromName(this Migration migration, char seper
         public static MigrationAttribute GetMigrationAttribute(this Type type)
         {
             var attribute = Attribute.GetCustomAttributes(type)
-                .FirstOrDefault(x => x.GetType().IsAssignableFrom(typeof(MigrationAttribute)));
+                .FirstOrDefault(x => x is MigrationAttribute);
             return (MigrationAttribute)attribute;
         }
 

readme.md

@@ -61,7 +61,7 @@ In every migration you have access to the document store, so you are able to do
 
 ### Runner
 
-Raven Migrations comes with a migration runner. It scans all provided assemblies for any classes implementing the **Migration** base class and then orders them according to their migration value. 
+Raven Migrations comes with a migration runner. It scans all provided assemblies for any classes implementing the **Migration** base class and then orders them according to their migration value.
 
 After each migration is executed, a document of type **MigrationDocument** is inserted into your database, to insure the next time the runner is executed that migration is not executed again. When a migration is rolled back the document is removed.
 
@@ -127,7 +127,7 @@ Raven Migrations lets you migrate at the **RavenJObject** level, giving full acc
 Alter.Collection("People", (doc, metadata) => { ... });
 ```
 
-Batching changes is taken care of with the default batch size being 128.  You can change the batch size if needed: 
+Batching changes is taken care of with the default batch size being 128.  You can change the batch size if needed:
 ```
 public void Collection(string tag, Action<RavenJObject, RavenJObject> action, int pageSize = 128)
 ```
@@ -234,6 +234,38 @@ Let's say that you refactor and move ```Person``` to another assembly.  So that
     }
 ```
 
+### Custom migration attributes
+
+If the `long` version number does not fit your versioning scheme, a custom
+attribute can inherit from `MigrationAttribute`.
+
+Example implementation for semantic versions:
+```
+    public class MigrationVersionAttribute : MigrationAttribute
+    {
+        public MigrationVersionAttribute(int major, int minor, int patch, int migration, params string [] profiles)
+            :base(CreateVersionNumber(major, minor, patch, migration), profiles)
+        {
+
+        }
+
+        private static long CreateVersionNumber(int major, int minor, int patch, int migration)
+        {
+            return major*100000000000L + minor*10000000L + patch*1000L + migration;
+        }
+    }
+}
+```
+
+Example usage in a migration:
+```
+    [MigrationVersion(6, 9, 11, 1)]
+    public class CustomVersionMigration : Migration
+    {
+        public override void Up() { /* ... */ }
+    }    
+```
+
 ## Integration
 
 We suggest you run the migrations at the start of your application to ensure that any new changes you have made apply to your application before you application starts. If you do not want to do it here, you can choose to do it out of band using a seperate application.
@@ -269,4 +301,3 @@ Thanks goes to [Sean Kearon](https://github.com/seankearon) who helped dog food
 
 This project strives to adhere to the [semver](http://semver.org) guidelines. See the [contributing](./CONTRIBUTING.md) and [maintaining](./MAINTAINING.md)
 guides for more on this.
-