new doc AFF support

src/development-guide/README.md

@@ -22,6 +22,7 @@ Development related information
 - [Overview](serializers/overview.md)
 - [Serializer Class](serializers/serializers.md)
 - [New Serializers](serializers/task-list.md)
+- [Adding AFF support](serializers/aff.md)
 - [File Naming and Formats](serializers/file-formats.md)
 
 ### Testing

src/development-guide/serializers/README.md

@@ -12,4 +12,5 @@ dir:
 - [Overview](overview.md)
 - [Serializer Class](serializers.md)
 - [New Serializers](task-list.md)
+- [Adding AFF support](aff.md)
 - [File Naming and Formats](file-formats.md)

src/development-guide/serializers/aff.md

@@ -0,0 +1,21 @@
+---
+title: Adding AFF support
+category: serializers
+order: 35
+---
+
+The [ABAP File Format (AFF)](https://github.com/SAP/abap-file-formats) is the preferred
+format for object types for which SAP provides an AFF object handler.
+
+For implementing AFF support for new object types already supported by AFF see the examples in the repository.
+
+abapGit has been backwards compatible for 10+ years, and whishes to continue to support all users going forward.
+This means reading old formats and writing new formats, and not breaking existing users, and users should not loose any data when switching to a new format.
+
+Suggested approach:
+
+* Read the old XML into the new AFF format carried by the INTF, https://github.com/abapGit/abapGit/tree/main/src/objects/aff_types
+* Persist the object given the data in the INTF
+* Serialize the object to AFF format
+
+Make sure to test and keep old and new examples in https://github.com/orgs/abapGit-tests

src/development-guide/serializers/task-list.md

@@ -22,9 +22,11 @@ The following list includes the mandatory and recommended tasks for adding a new
 abapGit maintainers will add your issue to a [central list](https://github.com/abapGit/abapGit/issues/5912) and, if there's no further discussion required, close it. 
 :::
 
-3. Implement the serializer class
-
-   Follow the instructions below. Often, it makes sense to use an existing serializer class as a template. This can save a lot of work especially if the new object type is similar to others.
+3. Implement the serializer class
+
+   Follow the instructions below. Often, it makes sense to use an existing serializer class as a template. This can save a lot of work especially if the new object type is similar to others.
+
+   If SAP provides an ABAP File Format object handler for the object type, follow [Adding AFF support](aff.md).
 
 ::: warning
 Your code must comply with the [development guidelines](/development-guide/read-first/guidelines.md) for abapGit. Most notably your code must be compatible with 7.02 ABAP syntax and available standard SAP objects, use prefixing of variables, be pretty-printed, and pass all abaplint checks.
@@ -48,7 +50,7 @@ You might get lots of abaplint errors. If you are uncertain how to resolve these
 
    Fork the abapGit repository and add a branch for your serializer class. Commit your implementation (the `zcl_abapgit_object_<type>` class) to the branch, and create a pull request to the abapGit repository. Reference your issue in the pull request and add a link to the test repository.
 
-   Note: Object types using the ABAP File Format must be added to the [AFF Registry](https://github.com/abapGit/abapGit/blob/d0167ff97dcf6f90ed2721c40d194a5fb34f3ea0/src/objects/aff/zcl_abapgit_aff_registry.clas.abap#L51-L61) as well.
+   Note: Object types using the ABAP File Format must be added to the [AFF Registry](aff.md#register-the-object-type) as well.
 
 7. Update documentation