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      1 # Copyright 2014 Google Inc. All Rights Reserved.
      2 #
      3 # Licensed under the Apache License, Version 2.0 (the "License");
      4 # you may not use this file except in compliance with the License.
      5 # You may obtain a copy of the License at
      6 #
      7 #      http://www.apache.org/licenses/LICENSE-2.0
      8 #
      9 # Unless required by applicable law or agreed to in writing, software
     10 # distributed under the License is distributed on an "AS IS" BASIS,
     11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     12 # See the License for the specific language governing permissions and
     13 # limitations under the License.
     14 
     15 """Utilities for making samples.
     16 
     17 Consolidates a lot of code commonly repeated in sample applications.
     18 """
     19 from __future__ import absolute_import
     20 
     21 __author__ = 'jcgregorio (at] google.com (Joe Gregorio)'
     22 __all__ = ['init']
     23 
     24 
     25 import argparse
     26 import os
     27 
     28 from googleapiclient import discovery
     29 from googleapiclient.http import build_http
     30 
     31 def init(argv, name, version, doc, filename, scope=None, parents=[], discovery_filename=None):
     32   """A common initialization routine for samples.
     33 
     34   Many of the sample applications do the same initialization, which has now
     35   been consolidated into this function. This function uses common idioms found
     36   in almost all the samples, i.e. for an API with name 'apiname', the
     37   credentials are stored in a file named apiname.dat, and the
     38   client_secrets.json file is stored in the same directory as the application
     39   main file.
     40 
     41   Args:
     42     argv: list of string, the command-line parameters of the application.
     43     name: string, name of the API.
     44     version: string, version of the API.
     45     doc: string, description of the application. Usually set to __doc__.
     46     file: string, filename of the application. Usually set to __file__.
     47     parents: list of argparse.ArgumentParser, additional command-line flags.
     48     scope: string, The OAuth scope used.
     49     discovery_filename: string, name of local discovery file (JSON). Use when discovery doc not available via URL.
     50 
     51   Returns:
     52     A tuple of (service, flags), where service is the service object and flags
     53     is the parsed command-line flags.
     54   """
     55   try:
     56       from oauth2client import client
     57       from oauth2client import file
     58       from oauth2client import tools
     59   except ImportError:
     60       raise ImportError('googleapiclient.sample_tools requires oauth2client. Please install oauth2client and try again.')
     61 
     62   if scope is None:
     63     scope = 'https://www.googleapis.com/auth/' + name
     64 
     65   # Parser command-line arguments.
     66   parent_parsers = [tools.argparser]
     67   parent_parsers.extend(parents)
     68   parser = argparse.ArgumentParser(
     69       description=doc,
     70       formatter_class=argparse.RawDescriptionHelpFormatter,
     71       parents=parent_parsers)
     72   flags = parser.parse_args(argv[1:])
     73 
     74   # Name of a file containing the OAuth 2.0 information for this
     75   # application, including client_id and client_secret, which are found
     76   # on the API Access tab on the Google APIs
     77   # Console <http://code.google.com/apis/console>.
     78   client_secrets = os.path.join(os.path.dirname(filename),
     79                                 'client_secrets.json')
     80 
     81   # Set up a Flow object to be used if we need to authenticate.
     82   flow = client.flow_from_clientsecrets(client_secrets,
     83       scope=scope,
     84       message=tools.message_if_missing(client_secrets))
     85 
     86   # Prepare credentials, and authorize HTTP object with them.
     87   # If the credentials don't exist or are invalid run through the native client
     88   # flow. The Storage object will ensure that if successful the good
     89   # credentials will get written back to a file.
     90   storage = file.Storage(name + '.dat')
     91   credentials = storage.get()
     92   if credentials is None or credentials.invalid:
     93     credentials = tools.run_flow(flow, storage, flags)
     94   http = credentials.authorize(http=build_http())
     95 
     96   if discovery_filename is None:
     97     # Construct a service object via the discovery service.
     98     service = discovery.build(name, version, http=http)
     99   else:
    100     # Construct a service object using a local discovery document file.
    101     with open(discovery_filename) as discovery_file:
    102       service = discovery.build_from_document(
    103           discovery_file.read(),
    104           base='https://www.googleapis.com/',
    105           http=http)
    106   return (service, flags)
    107