Dict to Query conversion

[Alan Etkin]

I wrote this snippet that accepts a database query represented as Python dictionary and builds a Query instance. I think this could be used by the DAL class for accepting this syntax:

>>> db({"op": "GT", "first": {"tablename": "auth_user", "fieldname": "id"}, "second": 0})
<Set (auth_user.id > 0)>

http://www.web2pyslices.com/slice/show/1593/class-for-building-db-queries-from-python-dictionaries

I think that Set could also support Set.as_dict() for mapping Query objects with the above syntax

I know there's also Query.__dict__ and Set.__dict__, but those attributes return non json-serializable objects and much of the data cannot be easily converted to protocols like JSON or XML.

[Massimo DiPierro]

It would be really be nice to have a way to do

  def dalservice(): db.expose_service()

and in a different application

  db = DAL('dal://127.0.0.1:8000/otherapp/default/dalservice')

i think your code may enable it.

On Jan 27, 2013, at 2:45 PM, Alan Etkin wrote:

I wrote this snippet that accepts a represented as Python dictionary and builds a Query instance. I think this could be used by the DAL class for accepting this syntax:

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[Alan Etkin]

It would be really be nice to have a way to do ...

 

I'm not sure I understood  expose_service, but with the experimental db.as_dict, we could return the model as xml/json.
The missing feature would be the serialization of the actions (different service resources). Perhaps it would be possible to register action definitions (args, output) in a service object so they can be consumed by expose_service in a similar way as pysimplesoap does.

About the dal(url), I belive this is more explicit and consistent with the other types of engines

remotedb = DAL("service://<url>")