Odoo 19 Breaking Changes: Developer Migration Reference

Overview

Odoo 19 refines patterns introduced in v17 and v18 while introducing its own breaking changes. The focus is on stricter validation, improved performance defaults, and cleaning up technical debt. This reference covers changes that affect custom module migration from v18 to v19.

ORM and Model Changes

Inheritance Patterns

Odoo 19 tightened inheritance validation:

• Classic inheritance (_inherit without _name) now validates that the parent model exists at module install time, not just at runtime
• Delegation inheritance (_inherits) validates that the delegated field exists and is a Many2one
• Prototype inheritance (_inherit with _name) validates that no field name collisions exist with the parent
• Mixin classes now enforce that _abstract = True is set explicitly

Field Definitions

• precompute=True is now the default for stored computed fields that depend only on stored fields — previously this was opt-in
• compute_sudo default behavior was standardized — computed fields using sudo() in compute methods must declare compute_sudo=True
• Related fields with store=True have improved cache invalidation, which may surface previously hidden bugs
• Currency fields using currency_field parameter now validate that the referenced field exists

ORM Methods

• create() multi-create (@api.model_create_multi) is now mandatory — single-record create() raises a deprecation warning
• unlink() triggers cascade validation more strictly — orphaned records in related tables are detected
• search() with invalid domain operators raises ValueError instead of silently ignoring
• mapped() performance was improved but behavior for nested dotted paths was standardized

View and XML Changes

• All views must declare model in the view record — omitting it raises an error during module installation
• XPath expressions are validated more strictly — malformed xpath raises clear errors instead of silent failures
• The groups attribute on fields in views now validates against existing group XML IDs at install time
• Form view sheet element is now required for all form views (previously optional for simple forms)
• Statusbar widget validates that the field is a Selection type

Frontend Changes

OWL Components

• All components must use the setup() pattern — constructor-based initialization raises errors
• The useEffect hook was refined for better cleanup handling
• Component props validation is now enforced in production mode (previously dev-only)
• Lazy-loaded component patterns were standardized

Web Client

• The action manager API was updated — custom client actions need review
• Notification system uses new severity levels
• Dialog component API changed — custom dialogs need updates
• Breadcrumb generation logic changed for multi-level navigation

Security Changes

• API key authentication was hardened — tokens now have configurable expiry
• CORS policy enforcement is stricter by default
• CSRF token validation was expanded to cover more endpoints
• Session fixation protections were enhanced

Configuration Changes

• db_maxconn default changed from 64 to 32 per worker for better resource management
• limit_time_real default was increased for long-running operations
• New websocket_keep_alive_timeout parameter added
• Log format includes request ID for better traceability

Removed Features

• QWeb report engine fallback to Jinja2 was removed completely
• Legacy form view oe_button_box without name attribute support dropped
• Old-style action definitions without type field removed
• tree tag in XML — list views must use <list> tag (tree tag removed entirely)

Migration Steps

1. Update __manifest__.py to version 19.0.x.x.x
2. Replace <tree> tags with <list> in all view definitions
3. Add @api.model_create_multi to all create() overrides
4. Verify all inheritance declarations are valid
5. Add sheet element to form views missing it
6. Update OWL components to use setup() pattern exclusively
7. Test all views for stricter validation errors
8. Review record rules and security for tightened enforcement

DeployMonkey

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