Module Merging

Example

From version 15.0 to version 16.0, the fetchmail_outlook module has been merged into microsoft_outlook.

Result without migration script / Expected Result

V15 table `ir_module_module`

id	name	state	latest_version
200	fetchmail_outlook	installed	15.0.1.0
304	microsoft_outlook	installed	15.0.1.0

V16 table `ir_module_module` (Without openupgrade)

id	name	state	latest_version
200	fetchmail_outlook	to upgrade	15.0.1.0
304	microsoft_outlook	installed	16.0.1.0

Problem:

The v15 module remains in a to upgrade state.

As a result:

the data will be recreated instead of having their xml_id renamed
the database is in a unstable state.

V16 table `ir_module_module` (With openupgrade)

id	name	state	latest_version
304	microsoft_outlook	installed	16.0.1.0

Contribution to OpenUpgrade

apriori.py file

The list of the merged modules is present in a apriori.py file in each version of openupgrade.

Until version 13, the file is present in this path: odoo/addons/openupgrade_records/lib/apriori.py.
from version 14.0 onwards, the file is present in this path: openupgrade_scripts/apriori.py.

Add a key in the following dict:

merged_modules = {
    "fetchmail_outlook": "microsoft_outlook",
}

See Full v16 apriori file.

pre-migration.py file

in the migration folder of the base module, add:

from odoo.addons.openupgrade_scripts.apriori import merged_modules

@openupgrade.migrate(use_env=False)
def migrate(cr, version):
    openupgrade.update_module_names(
        cr,
        merged_modules.items(),
        merge_modules=True,
    )

See Full v16 base pre migration file.

Note: The addition is done at the initialization of the OpenUpgrade Project, for each new version. So you will generally not have to do this, as it’s only OpenUpgrade maintainers that initialize the OpenUpgrade Project.

Coverage File

A coverage file is present in each version:

Until version 13, the file is present in this path: odoo/openupgrade/doc/source/modulesXXX-YYY.rst.
from version 14.0 onwards, the file is present in this path: docsource/modulesXXX-YYY.rst.

Edit this file, and add the following text:

+-----------------------------------+---------+-------------------------------------------------+
| Module                            | Status  + Extra Information                               |
+===================================+=========+=================================================+
+-----------------------------------+---------+-------------------------------------------------+
| |del| fetchmail_outlook           | Done    | Merged into microsoft_outlook.                  |
+-----------------------------------+---------+-------------------------------------------------+

Notes

In the apriori.py file, in the merged_modules dict, put the Odoo renaming at the beginning, ordered by module name, then OCA modules renaming, with the mention of OCA repository. Example:

merged_modules = {
    # odoo
    "account_edi_facturx": "account_edi_ubl_cii",
    "account_edi_ubl": "account_edi_ubl_cii",
    "website_sale_gift_card": "website_sale_loyalty",
    # OCA/account-financial-tools
    "account_balance_line": "account",
    "account_move_force_removal": "account",
}

If your instance has custom modules, and if you took advantage of the migration to refactor these custom modules by merging them, you can add the following lines at the end of this file:

merged_modules.update({
    "my_obsolete_module": "my_main_module",
})

(no need in this case to propose a PR to the community)