Finance teams invoicing in Vietnam carry a compliance obligation that Odoo's standard accounting does not answer. account.move posts a document, numbers it with an ir.sequence, and renders a QWeb PDF — but Vietnamese e-invoicing requires that the same posting be transmitted to an authorised e-invoice service provider, receive back an official invoice code, be represented in a machine-readable structure alongside the human-readable copy, and be retrievable in that exact issued form for years afterwards. Nothing in Odoo Community or Enterprise does this. The usual fallback is a parallel workflow: post in Odoo, re-key into the provider's web portal, download the returned file, and reconcile two systems by hand at month end. That is where numbering diverges, where a customer receives a document the tax record does not recognise, and where a rejected submission sits unnoticed until someone reads an email.

We build a module that makes transmission part of posting. A new model — typically ecosire.einvoice.document — is created on account.move post and carries its own lifecycle state (draft, queued, sent, accepted, rejected, cancelled, replaced), the provider request and response payloads, the returned invoice code and lookup reference, and relations back to account.move and res.partner so the chain is traceable from either end. Transmission runs asynchronously through a queued job or an ir.cron sweep rather than inline in the write transaction, so a provider timeout never blocks a user's posting. Every call is stored with its request body, HTTP status, provider error code and timestamp, which is what turns "the invoice failed" into a specific, answerable question.

Tax handling is driven by your own master data, not a hard-coded table. We extend account.tax, product.template and product.category with the provider's tax-category and unit-of-measure codes, and a compute (@api.depends on the line taxes and product) resolves each account.move.line to the code set the provider expects. Exempt, zero-rated, non-declarable and reduced-rate cases each get an explicit mapping rather than falling through to a default, and a validation gate on post raises a clear message naming the specific tax or product that is unmapped — before the document is submitted and rejected. Partner-side data (tax code, legal name, address) is validated for format and completeness on res.partner, so the common rejection causes are caught inside Odoo.

Rejections are treated as a workflow, not an error log. A rejected document moves to rejected with the provider's reason surfaced on the form and posted to the chatter via message_post, and an mail.activity is scheduled for the responsible accountant. From there the correction path — adjustment or replacement, depending on what the original document's state allows — creates the linked corrective document and preserves the reference to what it supersedes, so the audit trail shows the full sequence rather than a silently amended record. Archiving stores the issued machine-readable file and the rendered human-readable copy as checksummed ir.attachment records, and a dedicated menu lets finance search and export by period, partner, tax code or document state. Access is governed by ir.model.access.csv plus record rules, so multi-company installs cannot see each other's issued documents, and provider credentials live in ir.config_parameter scoped per company rather than in source.

This is a build-to-order product: ECOSIRE develops it against your Odoo version (17.0, 18.0 or 19.0), your chart of accounts, and your specific e-invoice service provider's API contract — providers differ in authentication, payload schema and error semantics, so the connector is written to yours rather than assumed. It is not an instant download. After a short scoping call we confirm scope in writing, and typical delivery is one working week from that confirmation. You receive installable source, deployment on your staging database for UAT against the provider's test environment, and a git repository handover, so the module remains yours to maintain, extend, or hand to another team.