Export from Google App Engine Datastore Backup LevelDB format to JSON flat file

export.py

import sys, os, json
import datetime

sys.path.append(os.path.expanduser('~/google-cloud-sdk/platform/google_appengine/'))
from google.appengine.api.files import records
from google.appengine.datastore import entity_pb
from google.appengine.api import datastore

def myconverter(o):
    if isinstance(o, datetime.datetime):
        return o.isoformat()

for path, dirs, files in os.walk('./'):

    for fn in files:
        f = os.path.join(path, fn)
        if not fn.startswith('output'):
            continue

        with open(f, 'r') as raw:

            reader = records.RecordsReader(raw)

            for record in reader:
                entity_proto = entity_pb.EntityProto(contents=record)
                entity = datastore.Entity.FromPb(entity_proto)
                entity['table'] = path[2:]
                j = json.dumps(entity, default=myconverter)
                print (j)

Thanks for this ! It helped me export some data from an old App Engine app that I'd been putting off doing for years. I've forked it with some extra instructions and tweaks to better export entity kinds and key paths (ie entity identifiers) for my purposes.