scripts/interactive.py

   1 #!/usr/bin/python2.5
   2 #
   3 # Copyright 2009 the Melange authors.
   4 #
   5 # Licensed under the Apache License, Version 2.0 (the "License");
   6 # you may not use this file except in compliance with the License.
   7 # You may obtain a copy of the License at
   8 #
   9 #   http://www.apache.org/licenses/LICENSE-2.0
  10 #
  11 # Unless required by applicable law or agreed to in writing, software
  12 # distributed under the License is distributed on an "AS IS" BASIS,
  13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14 # See the License for the specific language governing permissions and
  15 # limitations under the License.
  16
  17 """This module supplies an interactive shell with remote api configured.
  18
  19 Usage is simple:
  20
  21 App Engine interactive console
  22 >>> from soc.models.user import User
  23 >>> gen = lambda: User.all()
  24 >>> it = deepFetch(gen)
  25 >>> result = [i for i in it]
  26 """
  27
  28 __authors__ = [
  29   '"Sverre Rabbelier" <sverre@rabbelier.nl>',
  30 ]
  31
  32
  33
  34 import code
  35 import getpass
  36 import os
  37 import sys
  38 import sys
  39
  40
  41 def auth_func():
  42   """Returns a tuple with username and password.
  43   """
  44
  45   return raw_input('Username:'), getpass.getpass('Password:')
  46
  47
  48 def deepFetch(queryGen,key=None,batchSize = 100):
  49   """Iterator that yields an entity in batches.
  50
  51   Args:
  52     queryGen: should return a Query object
  53     key: used to .filter() for __key__
  54     batchSize: how many entities to retrieve in one datastore call
  55
  56   Retrieved from http://tinyurl.com/d887ll (AppEngine cookbook).
  57   """
  58
  59    # AppEngine will not fetch more than 1000 results
  60   batchSize = min(batchSize,1000)
  61
  62   query = None
  63   done = False
  64   count = 0
  65
  66   if key:
  67     key = db.Key(key)
  68
  69   while not done:
  70     query = queryGen()
  71     if key:
  72       query.filter("__key__ > ",key)
  73     results = query.fetch(batchSize)
  74     for result in results:
  75       count += 1
  76       yield result
  77     if batchSize > len(results):
  78       done = True
  79     else:
  80       key = results[-1].key()
  81
  82
  83 def remote(args):
  84   """Starts a shell with the datastore as remote_api_stub.
  85   """
  86
  87   from google.appengine.ext import db
  88   from google.appengine.ext.remote_api import remote_api_stub
  89
  90   app_id = args[0]
  91
  92   if len(args) > 1:
  93     host = args[1]
  94   else:
  95     host = '%s.appspot.com' % app_id
  96
  97   remote_api_stub.ConfigureRemoteDatastore(app_id, '/remote_api', auth_func, host)
  98
  99   context = {
 100       'deepFetch': deepFetch,
 101   }
 102
 103   code.interact('App Engine interactive console for %s' % (app_id,), None, context)
 104
 105
 106 def main(args):
 107   """Sets up the sys.path and environment for development.
 108   """
 109
 110   here = os.path.abspath(__file__)
 111   here = os.path.join(os.path.dirname(here), '..')
 112   here = os.path.normpath(here)
 113
 114   appengine_location = os.path.join(here, 'thirdparty', 'google_appengine')
 115
 116   extra_paths = [here,
 117                  os.path.join(appengine_location, 'lib', 'django'),
 118                  os.path.join(appengine_location, 'lib', 'webob'),
 119                  os.path.join(appengine_location, 'lib', 'yaml', 'lib'),
 120                  appengine_location,
 121                  os.path.join(here, 'app'),
 122                 ]
 123
 124   sys.path = extra_paths + sys.path
 125
 126   os.environ['SERVER_SOFTWARE'] = 'Development Interactive Shell'
 127
 128   import main as app_main
 129
 130   remote(args)
 131
 132
 133 if __name__ == '__main__':
 134   if len(sys.argv) < 2:
 135     print "Usage: %s app_id [host]" % (sys.argv[0],)
 136     sys.exit(1)
 137
 138   main(sys.argv[1:])