List of Menu bl_idnames? INFO_MT_file_export, etc

Question

I am loosing my mind here.

Every example addon in blender uses bpy.types.INFO_MT_file_export yet not a single doc explains where the hell the name INFO_MT_file_export comes from.

The doc for bpy.types doesn’t have anything about it. Which leads me to believe we are accessing some object.

I can draw the conclusion that it’s a bl_idname for the info menu and the export submenu, but I don’t understand why we can access it using the dot operator inside of bpy.types, or why we can call the append and remove function if it’s a type of Menu.

Moreover, is there a list or something of all of these predefined possible menu ids?

Answer 1

Mousing over the base of a menu gives you the bl_idname.

If you right click and select edit source it will open up the code for that space in the text editor

In this file you will find

class INFO_MT_file_export(Menu):
    bl_idname = "INFO_MT_file_export"
    bl_label = "Export"

    def draw(self, context):
        if bpy.app.build_options.collada:
            self.layout.operator("wm.collada_export", text="Collada (Default) (.dae)")
        if bpy.app.build_options.alembic:
            self.layout.operator("wm.alembic_export", text="Alembic (.abc)")

which affirms that it is a Menu class. The naming convention used by blender for operators and menus is <SPACE>_<TYPE>_<name> where in this case it's the INFO space, is menu type MT and named file_export.

When a blender menu (or operator) is registered it becomes known to bpy.types. If the naming convention is followed, we can find all menus in the info space, simply by using auto-complete in the python console.

>>> bpy.types.INFO_MT_
                      add(
                      armature_add(
                      ...
                      file(
                      file_export(
                      file_external_data(
                      file_import(
                      file_previews(
                      ...
                      window(

To get a complete list of all menus, you can use python's built-in dir() function:

base_type = bpy.types.Menu
for typename in dir(bpy.types):
    bl_type = getattr(bpy.types, typename)
    if issubclass(bl_type, base_type):
        print (bl_type)