CouchObject.py

class CouchObject(object):
    '''
        Convert between a CouchDB document and Python object. 
        Create Python objects while maintaining a schema-free database.
        Define object properties without storing null fields.
    '''

    @property
    def id(self):
        return self._id
    
    @property
    def rev(self):
        return self._rev

    def all_fields(self):
        # return a list of expected fields
        raise NotImplementedError("all_fields must return a list of all fields for %s" % self.__class__)

    def __init__(self, **kwargs):
        self.server, self.db = get_server_db()

        # create object properties for all desired fields
        for field_name in self.all_fields():
            # check if field exists in document
            if field_name in kwargs and kwargs[field_name] is not None:
                value = kwargs[field_name]
            else:
                value = None
            setattr(self, field_name, value)

    def to_dict(self):
        # dictionary from properties
        data_dict = {}
        for field_name in self.all_fields():
            value = getattr(self, field_name)
            if value is not None: # don't store null fields!
                data_dict[field_name] = value
        return data_dict     

    def save(self):
        self.db.update([self.to_dict()])
    
    @staticmethod
    def save_batch(docs):
        server, db = get_server_db()
        db.update([doc.to_dict() for doc in docs])
    
    def delete(self):
        del self.db[self._id]