[15.0] Backport of the einvoicing stack — what it takes, and a request for a 15.0 branch

[njeudy]

Hi Alexis,

We (Alusage) now need the einvoicing stack on Odoo 15.0 for a customer, so we started a backport — this time from our 16.0 branch, not from 18.0.

As for 16.0 (#28) and 19.0 (#35), there is no 15.0 branch on this repo — would you be willing to create one? We'd then submit a proper PR against it. Everything is public in the meantime:

https://github.com/Alusage/fr-einvoicing/tree/MIG-15.0-account_invoice_en16931 (branched off MIG-16.0-account_invoice_en16931)

This is WIP: nothing is installed or tested on a 15.0 database yet. Opening early so you can tell us if any of it is a bad idea.

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The good news: 16.0 → 15.0 is a much smaller step than 18.0 → 16.0

The hard part of the 16.0 backport — rewriting the tax layer of the 18.0 generic tax engine on top of compute_all() — carries over unchanged. compute_all() has the same signature on 15.0 (only the 16.0 fixed_multiplicator kwarg is missing, and the module never passes it). Same for the other three 18.0→16.0 chores:

• _("txt") % arg — GettextAlias.__call__(source, *args, **kwargs) is byte-for-byte identical on 15.0 and 16.0, so the rewritten calls stay as they are.
• View syntax (attrs=, <tree>, o_setting_box) — unchanged on 15.0.
• PDF/A-3: OdooPdfFileWriter.convert_to_pdfa() already exists on 15.0, in the same shape, so _en16931_pdf_to_pdfa() needs no change at all. That one was a nice surprise.

There is no JS in the stack, so the OWL 1 / OWL 2 split does not come into play.

What actually has to be rewritten: the report layer

ir.actions.report was reworked in 16.0 (per-record streams). On 15.0 none of these exist:

• _render_qweb_pdf_prepare_streams(report_ref, data, res_ids) — the hook account_invoice_en16931/models/ir_actions_report.py overrides;
• _get_report(report_ref) (base) and _is_invoice_report(report_ref) (account);
• the report_ref first argument of _render() / _render_qweb_pdf().

15.0 renders the whole PDF in one go, so the Factur-X injection has to move to _post_pdf(save_in_attachment, pdf_content, res_ids) — which is exactly what your own account_invoice_facturx does on OCA/edi 15.0, so we'll follow that. _get_pdf_invoice_bin() becomes report._render([self.id]) on the report recordset.

Two OCA prerequisites are missing on 15.0

Both landed upstream on 16.0 while the 16.0 backport was running; on 15.0 they are simply not there. We backported them and will submit them to OCA:

1. VATEX codes on account_tax_unece (data/unece_tax_vatex.xml, unece_vatex_id, _compute_unece_vatex_id) — https://github.com/Alusage/community-data-files/tree/15.0-add-unece-vatex (your two 16.0 commits cherry-picked, migration renamed to 15.0.2.0.0, tree view re-anchored on the 15.0 field).
2. l10n_fr_siret helpers (is_france_country, _get_siren(), _get_siret(), _get_nic(), VAT↔SIREN consistency check) — https://github.com/Alusage/l10n-france/tree/15.0-siret-get-methods (your commit 9e662b1a + the self.env._ follow-up). The partner view keeps its 15.0 layout, since l10n_fr_siret still defines company_registry itself on that version.

Two modules left out for now

• l10n_fr_einvoicing_dashboard_banner — account_dashboard_banner only exists on 16.0 (OCA/account-financial-tools). Left installable: False.
• l10n_fr_einvoicing_import — account_invoice_import was never migrated to 15.0: OCA/edi has it on 14.0 and 16.0, nothing in between, and base_business_document_import is missing too. We intend to migrate both from 16.0 (they contain no 16.0-only API as far as we can tell) and submit them to OCA/edi, but that is a separate piece of work.

The other eight modules are in scope.

Anything you'd rather we did differently, tell us early — happy to adjust.

[njeudy]

@alexis-via can you create 15.0 branch ?

[alexis-via]

I created the branch 15.0