plonedexterity

list the fields of a dexterity object

I'd like to list all the fields (and the values) of a dexterity object.

I can easily access a single field value like this myobject.myfield

But I don't know how to list all the available fields of an object.

Solution

  • Dexterity objects are defined by a schema, which is enumerable:

    from zope.interface.interfaces import IMethod

for name, desc in IYourDexteritySchema.namesAndDescriptions():
    value = getattr(yourDexterityInstance, name)
    if IMethod.providedBy(desc):
        # It's a method, call it
        value = value()

    Here I use the .namesAndDescriptions() method, but you can also just use the interface as an iterator if you don't have any methods on your schema:

    for name in IYourDexteritySchema:
    value = getattr(yourDexterityInstance, name)

    Last but not least, zope.schema has a utility method named getFieldsInOrder that will filter on zope.schema fields in an interface; the above methods also list methods and non-schema attributes, getFieldsInOrder only lists zope.schema specific attribute types:

    from zope.schema import getFieldsInOrder

for name, field in getFieldsInOrder(IYourDexteritySchema):
    value = getattr(yourDexterityInstance, name)

    If you defined the schema through-the-web, you may not know how to look up the interface for your type. You can also retrieve the schema interface through the Factory Type Information, or FTI for short:

    from plone.dexterity.interfaces import IDexterityFTI
from zope.component import getUtility

schema = getUtility(IDexterityFTI, name='your.dexterity.type').lookupSchema()

    where schema now holds your interface.