Profiles API

2013-03-13 - Proposal Draft

The Profiles API bring together the various interfaces that Avocado exposes for describing, accessing, and interpreting a data field. These currently include:

• a DataField model instances which represents the descriptors and metadata for the field itself
• a data Interface (proposal) which exposes the direct data access API at the field-level
• a query processing and interpretation API (supersedes the Translator API) which exposes the query parsing, validation, construction, and execution behavior of the field
• a Formatter component (not yet defined at the field level) for introducing formatting capabilities

In addition, the Profiles API removes the need to use the database-backend components of Avocado which increases the stability of the API (i.e. a bad data migration won't alter the data API behavior).

Profiles are exposed on the DataField or DataConcept instances under the profile property, although most public API methods will be proxied directly on the instance.

from avocado.models import DataField

f = DataField.init('app.model.field')
f.profile

Profiles can be directly registered for model fields:

from avocado import profiles
# Register a custom profile or set of options for the
# default profile.
profiles.register_field('app.model.field', {...})

Concepts can be defined similarly:

# Concept name, a list of fields, and an optional profile instance
# or dict of options for the default profile.
profiles.register_concept('some name', ['app.model.field', ...], {...})

In either case, the {...} can be a dict of options passed into the respective *Profile class or it can be a *Profile instance itself. This enables subclassing and customizing the behavior directly rather than initializing via options.