Monday, August 11, 2014

Bescheinigungen

Worked on welfare.aids as analyzed with Gerd:

  • aids.Confirmation (Hilfebestätigung) als base class. Gemeinsame Felder: start_date, end_date, aid_type, author, signer, board, board_date

    Und dann via MTI mindestens drei Unterklassen:

    • IncomeConfirmation (Einkommensbescheinigung) : EiEi, Ausländerbeihilfe
    • RefundConfirmation (Kostenrückerstattung) : AMK
    • OtherConfirmation (Sonstige) : Lebensmittelbank

AidType.content_type : Art der Unterklasse. Darf nicht mehr geändert werden wenn mindestens ein Record existiert.

User-Interface : eine HtmlBox mit einer Aktion für jede Bestätigungsart.

Datenmigration : unwichtig, weil ich die einfach manuell rauskommentieren kann.

Choosers on subclasses

I discovered and fixed a subtle framework bug. For example when I defined a base model and two subclasses thereof:

class Confirmation(dd.Model):

    aid_type = dd.ForeignKey(...)

    @classmethod
    def get_aid_types(cls):
        ct = ConfirmationTypes.get_by_value(dd.full_model_name(cls))
        return rt.modules.aids.AidType.objects.filter(confirmation_type=ct)

class A(Confirmation):
    ...

class B(Confirmation):

    ...

Then the combobox for aid_type on an A row and of a B row had the same content. It is possible (I didn’t verify) that this happened only for MTI constellations, i.e. when the model which defines the aid_type field was not abstract.

Explanation: This was because Lino stored these choosers on the database field object. Which caused the chooser for A.aid_type to be overwritten by the chooser for B.aid_type.

Solution: choosers are now stored in a dict _lino_choosers on the model (or action).

TODO: replace the insert method of ConfirmationsByClient so that it asks for the ConfirmationType and inserts into corresponding the MTI child and not into the base model Confirmation.

The easy solution would be an HtmlBox with one clickable action per ConfirmationType.