On Dec 20, 5:04 pm, "Rick Morrison" <[EMAIL PROTECTED]> wrote: > You're not going to be able to serialize Python class instances in JSON: > json strings are simple object literals limited to basic Javascript types. > Pickle does some pretty heavy lifting to serialize and reconstitute class > instances.
I've already figured this out -- you can use class "hinting" as outlined in this page: http://json-rpc.org/wiki/specification So a datetime using this format and converted to JSON might look like: "modification_time": {"__jsonclass__": ["datetime.datetime", [2007, 12, 19, 23, 3, 2, 2]]} My deserialization routine loads the datetime module, then gets the datetime attribute (which in this case is a type, but could be a function too), and calls that with the arguments in the list. This sort of thing works for generic classes too using the pickle __reduce__ hooks. The JSON part I'm actually handling through cjson or simplejson -- my serialization/deserialization is working all on python objects. > Easiest way to store JSON in the database is to limit the type of data you > store in JSON strings to straightforward objects that only use primitive JS > types, and then serialize back and forth to Python dictionaries. That's what > libraries like SimpleJSON or cJSON do. Using Sqlalchemy, you can then store > those JSON strings in database VARCHARS, TEXT and so on fields. I don't really want to store JSON in the DB, but just use it as a serialization format for sqlalchemy objects. We want our frontend to render data from the same type of object with a couple different possible backend sources. One being the database through the sqlalchemy ORM and another being some sort of JSON/XML interface that we can backend from whatever... --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To post to this group, send email to sqlalchemy@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~----------~----~----~----~------~----~------~--~---
