Block out a load of IDs

gistfile1.py

from google.appengine.ext import db
import sys
import inspect

def fetch_all(model_or_query):
    '''Fetch all the entities of the given model, or satisfying the given query.
    '''
    if isinstance(model_or_query, type) and issubclass(model_or_query, db.Model):
        query = model_or_query.all(keys_only=False)
    elif isinstance(model_or_query, db.Query):
        query = model_or_query
    else:
        raise Exception("model_or_query is neither a model nor a query")
    
    results = []
    while True:
        to_fetch = query.fetch(500)
        results += to_fetch
        if len(to_fetch) < 500:
            return results
        query.with_cursor(query.cursor())

def do_the_business():
    model_classes = inspect.getmembers(sys.modules["core.models"], inspect.isclass)
    for item in model_classes:
        cls = item[1]
        cls_name = item[0]
        if issubclass(cls, db.Model) and cls.__name__ != "PolyModel":
            print("getting data for %s" % cls_name)
            highest_id = 0
            all_instances = fetch_all(cls.all(keys_only=True))
            for e in all_instances:
                id = e.id()
                highest_id = id if id > highest_id else highest_id
            print("highest_id: %d" % highest_id)
            if highest_id:
                print("allocating ids until: %d" % highest_id)
                handmade_key = db.Key.from_path(cls_name, 1)
                db.allocate_id_range(handmade_key, 1, highest_id)