fetchevents.py

from __future__ import print_function
import argparse
import datetime
import json
import pickle
import os.path
import sys

from googleapiclient.discovery import build

import utils

# If modifying these scopes, delete the file token.pickle.
SCOPES = ['https://www.googleapis.com/auth/calendar.readonly']
SECRETS_FILE = 'files/credentials.json'
TOKEN_FILE = 'files/token.pickle'


def parse_args(args):
    parser = argparse.ArgumentParser()
    parser.add_argument('--token', default=TOKEN_FILE, help='Token file location')
    parser.add_argument('--count', default=10, help='Number of events to fetch, 10 by default')
    parser.add_argument('--secrets', default=SECRETS_FILE, help='File with google calendar oath credentials location')
    parser.add_argument('--scope', action='append', default=SCOPES,
                        help='Additional scopes to parse, default is {}'.format(SCOPES[0]))
    parser.add_argument('--id', default='primary', help='Calendar id, default is primary')
    parser.add_argument('--output', help='File to save fetched results')
    return parser.parse_args(args)


def _fetch_eventlist(creds, count, calendar_id='primary'):
    """Returns a list of dicts {date, name, description, location}"""

    service = build('calendar', 'v3', credentials=creds)

    # Call the Calendar API
    now = datetime.datetime.utcnow().isoformat() + 'Z' # 'Z' indicates UTC time
    events_result = service.events().list(calendarId=calendar_id, timeMin=now,
                                          maxResults=count, singleEvents=True,
                                          orderBy='startTime').execute()
    results = []

    def parse_date(start, date_format):
        try:
            return datetime.datetime.strptime(start, date_format)
        except ValueError:
            return None

    for event in events_result.get('items', []):
        start = event['start'].get('dateTime', event['start'].get('date'))
        start_dt = parse_date(start, "%Y-%m-%dT%H:%M:%S%z")
        start_dt = next((parse_date(start, f) for f in ["%Y-%m-%dT%H:%M:%S%z", "%Y-%m-%d"] if parse_date(start, f)), None)
        # XXX FIXME A quick hack, figure out why dateparsing of +offset is inconsistent on different machines
        # (python 3 version?)
        start_dt = start_dt if start_dt else parse_date(start.split('+')[0], "%Y-%m-%dT%H:%M:%S")
        if not start_dt:
            # don't know how to parse date, skipping event
            continue
        # parse date here for the frontend component to use
        # EVENT_LINK found in description will be removed and put as url in google location link
        # VENUE will be taken from the location (hope we are lucky here) and displayed in the event description
        start_details = {"month": start_dt.strftime("%b"), "day": start_dt.day, "year": start_dt.year,
                         "time": start_dt.strftime("%H:%M"), "datetime": start_dt.strftime("%Y-%m-%d %H%M")}
        url = next((w for w in event.get('description', '').split() if w.startswith('http')), None)
        location = ('https://www.google.com/maps/search/?api=1&query={}'.format(event['location'].replace('&', '%26'))
                    if event.get('location') else None)
        venue = event.get('location').split(',')[0] if location else ''
        res = {'start': start_details, 'name': event['summary'], 'description': venue,
               'location': location, 'url': url}
        results.append(res)
    return results


def main():
    parsed = parse_args(sys.argv[1:])
    try:
       creds = utils.get_creds(parsed.token, parsed.secrets, parsed.scope)
       events = _fetch_eventlist(creds, parsed.count, parsed.id)
       output = open(parsed.output, 'w') if parsed.output else sys.stdout
       json.dump(events, output)
    except Exception as e:
        # XXX FIXME in desperate need of proper logging
        print("An error has occurred: {}". format(str(e)))

if __name__ == '__main__':
    main()