Parent resides in datastore, assign children uploaded using CSV bulkloader

Question

Presently I have a Team residing in the datastore:

team = Team.get_by_key_name('Plants')

And I have the following CSV file in my local computer:

name,level
Pea Shooter,1
Threepeater,3
Melon-pult,20

My bulkloader.yaml looks like this:

python_preamble:
- import: models
- import: my_transforms

transformers:
- kind: Character
  connector: csv
  property_map:
  - property: name
    external_name: name

  - property: level
    external_name: level
    import_transform: my_transforms.transform_integer

I wrote a models.py that looks like this:

from google.appengine.ext import db

class Team(db.Model):
  name = db.StringProperty()

class Character(db.Model):
  name = db.StringProperty()
  level = db.IntegerProperty()

I also wrote a my_transforms.py:

def transform_integer(integer_string):
  return int(integer_string)

Question: How do I upload the CSV file so that when the Characters enter the datastore, their parent properties are assigned to team?

Answer 1

The first answer lacks detail but I was able to glean some information from it.

I added another column to my CSV file named Character.csv:

team,name,level
Plants,Pea Shooter,1
Plants,Threepeater,3
Plants,Melon-pult,20

The bulkloader.yaml now looks like this:

python_preamble:
- import: models
- import: my_transforms

transformers:
- kind: Character
  connector: csv
  property_map:
  - property: __key__
    external_name: team
    import_transform: transform.create_deep_key(('Team', 'team', False),
                                                ('Character', 'name', False))

  - property: name
    external_name: name

  - property: level
    external_name: level
    import_transform: my_transforms.transform_integer

Then I do the following in the Terminal:

$ cd /path/to/app
$ appcfg.py upload_data --config_file=bulkloader.yaml \
                        --filename=Character.csv \
                        --kind=Character \
                        --url=http://localhost:8082/_ah/remote_api