Started the 2.7 release post.

Author: hikalkan

docs/en/Blog-Posts/2020-05-08 v2_7_Release/Post.md

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+# ABP Framework v2.7.0 Has Been Released!
+
+The **ABP Framework** & and the **ABP Commercial** v2.7 have been released. We hadn't created blog post for   the 2.4, 2.4 and 2.6 releases, so this post will also cover **what's new** with these releases and **what we've done** in the last 2 months.
+
+## About the Release Cycle & Development
+
+Reminding that we had started to release a new minor feature version **in every two weeks**, generally on Thursdays. Our goal is to deliver new features as soon as possible.
+
+We've completed & merged hundreds of issues and pull requests with **1,300+ commits** in the last 7-8 weeks, only for the ABP Framework repository. Daily commit counts are constantly increasing:
+
+![github-contribution-graph](github-contribution-graph.png)
+
+ABP.IO Platform is rapidly growing and we are getting more and more contributions from the community.
+
+## What's New?
+
+In the last few releases, we've mostly focused on providing ways to extend existing modules when you use them as NuGet/NPM Packages. We've also added some useful features and some helpful guides.
+
+### Object Extending System
+
+The Object Extending System allows module developers to create extensible modules and allows application developers to customize and extend a module easily.
+
+For example, you can add two extension properties to the user entity of the identity module:
+
+````csharp
+ObjectExtensionManager.Instance
+    .AddOrUpdate<IdentityUser>(options =>
+        {
+            options.AddOrUpdateProperty<string>("SocialSecurityNumber");
+            options.AddOrUpdateProperty<bool>("IsSuperUser");
+        }
+    );
+````
+
+It is easy to define validation rules for the properties:
+
+````csharp
+ObjectExtensionManager.Instance
+    .AddOrUpdateProperty<IdentityUserCreateDto, string>(
+        "SocialSecurityNumber",
+        options =>
+        {
+            options.Attributes.Add(new RequiredAttribute());
+            options.Attributes.Add(
+                new StringLengthAttribute(32) {
+                    MinimumLength = 6 
+                }
+            );
+        });
+````
+
+You can even write custom code to validate the property. It automatically works for the objects those are parameters of an application service, controller or a page.
+
+While extension properties of an entity are normally stored in a single JSON formatted field in the database table, you can easily configure to store a property as a table field using the EF Core mapping:
+
+````csharp
+ObjectExtensionManager.Instance
+    .AddOrUpdateProperty<IdentityUser, string>(
+        "SocialSecurityNumber",
+        options =>
+        {
+            options.MapEfCore(b => b.HasMaxLength(32));
+        }
+    );
+````
+
+See the [Object Extensions document](https://docs.abp.io/en/abp/latest/Object-Extensions) for details about this system.
+
+### Guide: Customizing the Existing Modules
+
+[Customizing the Existing Modules guide](https://docs.abp.io/en/abp/latest/Customizing-Application-Modules-Guide) explains all the ways of extending/customizing a reusable module including [entities](https://docs.abp.io/en/abp/latest/Customizing-Application-Modules-Extending-Entities), [services](https://docs.abp.io/en/abp/latest/Customizing-Application-Modules-Overriding-Services) and the [user interface](https://docs.abp.io/en/abp/latest/Customizing-Application-Modules-Overriding-User-Interface).
+
+### Guide: EF Core Database Migrations
+
+TODO