chiark - git - matthewv - gooswapper/blob - gooswapper.py

   1 #!/usr/bin/env python3
   2
   3 import sys
   4 import getpass
   5 import os
   6 import pickle
   7 import collections
   8 import logging
   9 logger = logging.getLogger('gooswapper')
  10 logger.setLevel(logging.INFO)
  11 consolelog = logging.StreamHandler()
  12 consolelog.setLevel(logging.INFO)
  13 logformatter = logging.Formatter('%(name)s - %(levelname)s - %(message)s')
  14 consolelog.setFormatter(logformatter)
  15 logger.addHandler(consolelog)
  16 #We can't use this, because that way all the libraries' logs spam us
  17 #logging.basicConfig(level=logging.INFO)
  18
  19 #Exchange-related library
  20 sys.path.append("/upstreams/exchangelib")
  21 import exchangelib
  22
  23 #Google calendar-api libraries
  24 import httplib2
  25 import apiclient.discovery
  26 import oauth2client
  27 import oauth2client.file
  28 import oauth2client.client
  29
  30 #Not sure what the distribution approach here is...
  31 gcal_client_id = '805127902516-ptbbtgpq9o8pjr6r3k6hsm60j589o85u.apps.googleusercontent.com'
  32 gcal_client_secret = '8hpdxV3MauorryTDoZ1YK8JO'
  33
  34 #scope URL for r/w calendar access
  35 scope = 'https://www.googleapis.com/auth/calendar'
  36 #flow object, for doing OAuth2.0 stuff
  37 flow = oauth2client.client.OAuth2WebServerFlow(gcal_client_id,
  38                                                gcal_client_secret,
  39                                                scope)
  40
  41
  42 gcal_authpath=".gooswap_gcal_creds.dat"
  43
  44 cachepath=".gooswapcache"
  45
  46 exchange_credential = None
  47
  48 CachedExEvent=collections.namedtuple('CachedExEvent',
  49                                      ['changekey','gcal_link'])
  50
  51 class ex_gcal_link(exchangelib.ExtendedProperty):
  52     distinguished_property_set_id = 'PublicStrings'
  53     property_name = "google calendar event id"
  54     property_type = 'String'
  55
  56 exchangelib.CalendarItem.register('gcal_link',ex_gcal_link)
  57
  58 def get_ex_event_by_itemid(calendar,itemid):
  59     return calendar.get(item_id=itemid)
  60
  61 def get_ex_event_by_id_and_changekey(acct,itemid,changekey):
  62     l=list(acct.fetch([(itemid,changekey)]))
  63     return list(acct.fetch([(itemid,changekey)]))[0]
  64
  65 def get_ex_cred(username="SANGER\mv3",password=None):
  66     if password is None:
  67         password = getpass.getpass(prompt="Password for user %s: " % username)
  68     return exchangelib.ServiceAccount(username,password)
  69
  70 def ex_login(emailaddr,autodiscover=True):
  71     global exchange_credential
  72     if exchange_credential is None:
  73         exchange_credential = get_ex_cred()
  74     return exchangelib.Account(emailaddr,
  75                                credentials = exchange_credential,
  76                                autodiscover = autodiscover)
  77
  78 def get_ex_events(calendar):
  79     ans={}
  80     for event in calendar.all().only('changekey','item_id','gcal_link'):
  81         if event.item_id in ans:
  82             logger.warning("Event item_id %s was duplicated!" % event.item_id)
  83         ans[event.item_id] = CachedExEvent(event.changekey,event.gcal_link)
  84     logger.info("%d events found" % len(ans))
  85     return ans
  86
  87 def ex_event_changes(old,new):
  88     olds = set(old.keys())
  89     news = set(new.keys())
  90     added = list(news-olds)
  91     deleted = list(olds-news)
  92     changed = []
  93     #intersection - i.e. common to both sets
  94     for event in olds & news:
  95         if old[event].changekey != new[event].changekey:
  96             changed.append(event)
  97     logger.info("%d events updated, %d added, %d deleted" % (len(changed),
  98                                                               len(added),
  99                                                               len(deleted)))
 100     return added, deleted, changed
 101
 102 def add_ex_to_gcal(ex_acct,
 103                    gcal_acct,gcal_tz,events,
 104                    added,
 105                    gcal_id="primary"):
 106     for ev_id in added:
 107         event = get_ex_event_by_itemid(ex_acct.calendar,ev_id)
 108         if event.is_all_day:
 109             gevent={}
 110             gevent["summary"]=event.subject
 111             gevent["end"]={"date": str(event.end.astimezone(gcal_tz).date())}
 112             gevent["start"]={"date": str(event.start.astimezone(gcal_tz).date())}
 113             if event.text_body.strip() != '':
 114                 gevent["description"] = event.text_body
 115             if event.location is not None:
 116                 gevent["location"] = event.location
 117             gevent["extendedProperties"]={"shared": {"ex_id": event.item_id}}
 118             gevent=gcal_acct.events().insert(calendarId=gcal_id, body=gevent).execute()
 119             event.gcal_link = gevent.get("id")
 120             event.save()
 121             events[event.item_id] = events[event.item_id]._replace(changekey=event.changekey)
 122         else:
 123             logger.warning("only all-day events supported")
 124
 125 def del_ex_to_gcal(ex_acct, gcal_acct, events, deleted, gcal_id="primary"):
 126     for ev_id in deleted:
 127         if events[ev_id].gcal_link is not None:
 128             gcal_acct.events().delete(calendarId=gcal_id,
 129                                       eventId=events[ev_id].gcal_link,
 130                                       sendUpdates="none").execute()
 131
 132 def get_gcal_cred():
 133     #each such file can only store a single credential
 134     storage = oauth2client.file.Storage(gcal_authpath)
 135     gcal_credential = storage.get()
 136     #if no credential found, or they're invalid (e.g. expired),
 137     #then get a new one; pass --noauth_local_webserver on the command line
 138     #if you don't want it to spawn a browser
 139     if gcal_credential is None or gcal_credential.invalid:
 140         gcal_credential = oauth2client.tools.run_flow(flow,
 141                                                       storage,
 142                                                       oauth2client.tools.argparser.parse_args())
 143     return gcal_credential
 144
 145 def gcal_login():
 146     gcal_credential = get_gcal_cred()
 147     # Object to handle http requests; could add proxy details
 148     http = httplib2.Http()
 149     http = gcal_credential.authorize(http)
 150     return apiclient.discovery.build('calendar', 'v3', http=http)
 151
 152 def get_gcal_timezone(gcal_account,calendarid="primary"):
 153     gcal = gcal_account.calendars().get(calendarId=calendarid).execute()
 154     return exchangelib.EWSTimeZone.timezone(gcal['timeZone'])
 155
 156 def main():
 157     try:
 158         with open(cachepath,"rb") as f:
 159             cache = pickle.load(f)
 160     except FileNotFoundError:
 161         cache = None
 162
 163     ex_account = ex_login("mv3@sanger.ac.uk")
 164     current = get_ex_events(ex_account.calendar)
 165
 166     gcal_account = gcal_login()
 167     gcal_tz = get_gcal_timezone(gcal_account)
 168
 169     if cache is not None:
 170         added,deleted,changed = ex_event_changes(cache,current)
 171         add_ex_to_gcal(ex_account,gcal_account,gcal_tz,current,added)
 172         #delete op needs the "cache" set, as that has the link ids in
 173         #for events that are now deleted
 174         del_ex_to_gcal(ex_account,gcal_account,cache,deleted)
 175
 176     with open(cachepath,"wb") as f:
 177         pickle.dump(current,f)
 178
 179 if __name__ == "__main__":
 180     main()
 181
 182