calendar-invite.py

import csv
import getpass
import sys
import os
import base64
import re

from email.utils import formataddr
from email.header import Header
from googleapiclient.discovery import build
from google.oauth2.credentials import Credentials
from google_auth_oauthlib.flow import InstalledAppFlow
from google.auth.transport.requests import Request
from templates.variable_mappings import variable_column_mapping

# Help and number of argument passed checker
if len(sys.argv) < 5:
    #DONT USE <LOBBY LINK VARIABLE>
    print("USAGE: python3 calendar-invite.py <template_file> <csv_file> <include_meet> <slot_time> (OPTIONAL)<variables_with_same_value_for_all_mails>")
    print('python3 calendar-invite.py selections/onboarding onboarding.csv YES slot_time="Tuesday, 3 June 2023, 10:00 PM - 11:00 PM"')
    print("python3 calendar-invite.py selections/onboarding onboarding.csv NO slot_time='Tuesday, 2 February 2030, 8:00 AM - 1:00 PM' number_of_applicants='250+'")
    sys.exit(1)
    
# If modifying SCOPES, delete the file token.json.
SCOPES = ["https://www.googleapis.com/auth/gmail.send", "https://www.googleapis.com/auth/calendar.events"]

# Various files being used
template_file = "./templates/" + sys.argv[1]
csv_file = "./csv/" + sys.argv[2]
signature_file = "./templates/signature"
hasMeet = (sys.argv[3].lower() == 'yes')

# Getting subject and mail body
lines = []
with open(template_file, "r") as file:
    subject_template = file.readline().strip()
    lines = file.readlines()[1:]  # Slice the list starting from index 2 (line number 3)
email_body_template = "".join(lines)
# Getting signature
with open(signature_file) as file:
    signature = file.read()

def convert_to_RFC3339(input):
    lookUp={'January': 1, 'February': 2, 'March': 3, 'April': 4, 'May': 5, 'June': 6, 'July': 7, 'August': 8, 'September': 9, 'October': 10, 'November': 11, 'December': 12}

    chunks = re.findall(r"[\w']+",input)
    chunks[2] = lookUp[chunks[2]]
    if chunks[6]=='PM':
        chunks[4]=int(chunks[4])+12
    if chunks[9]=='PM':
        chunks[7]=int(chunks[7])+12

    chunks[4]=str(chunks[4]).zfill(2)
    chunks[7]=str(chunks[7]).zfill(2)
    chunks[1]=str(chunks[1]).zfill(2)
    chunks[2]=str(chunks[2]).zfill(2)

    return [f"{chunks[3]}-{chunks[2]}-{chunks[1]}T{chunks[4]}:{chunks[5]}:00",f"{chunks[3]}-{chunks[2]}-{chunks[1]}T{chunks[7]}:{chunks[8]}:00"]

def create_event(sender, email_list, subject, message, timeRange, has_meet):
    formatted_sender = formataddr((str(Header('KOSS IIT Kharagpur', 'utf-8')), sender))
    attendee_data = []
    for address in email_list:
        attendee_data.append({'email': address})

    if(has_meet):
        event = {
            'summary': f'{subject}',
            'description': f'{message}',
            'start': {
                'dateTime': f'{timeRange[0]}+05:30',
                'timeZone': 'Asia/Kolkata'
            },
            'end': {
                'dateTime': f'{timeRange[1]}+05:30',
                'timeZone': 'Asia/Kolkata'
            },
            'attendees': attendee_data,
            'reminders': {
                'useDefault': False,
                'overrides': [
                #email reminder 1 day before event
                {'method': 'email', 'minutes': 24 * 60},
                #pop-up reminder 10 minutes before event
                {'method': 'popup', 'minutes': 10},
                ],
            },
            'guestsCanSeeOtherGuests': False,
            'guestsCanInviteOthers': False,
            "conferenceData": {"createRequest": {"requestId": "sample123", "conferenceSolutionKey": {"type": "hangoutsMeet"}}}
        }
        return event
    
    event = {
            'summary': f'{subject}',
            'description': f'{message}',
            'start': {
                'dateTime': f'{timeRange[0]}+05:30',
                'timeZone': 'Asia/Kolkata'
            },
            'end': {
                'dateTime': f'{timeRange[1]}+05:30',
                'timeZone': 'Asia/Kolkata'
            },
            'attendees': attendee_data,
            'reminders': {
                'useDefault': False,
                'overrides': [
                #email reminder 1 day before event
                {'method': 'email', 'minutes': 24 * 60},
                #pop-up reminder 10 minutes before event
                {'method': 'popup', 'minutes': 10},
                ],
            },
            'guestsCanSeeOtherGuests': False,
            'guestsCanInviteOthers': False,
        }
    return event

def send_event(service, event):
    event = service.events().insert(calendarId='primary', body=event, sendNotifications=True,sendUpdates='all',conferenceDataVersion=1).execute()
    print ('Event created: %s' % (event.get('htmlLink')))
    print ('Meet link: %s' % (event.get('hangoutLink')))
    return event

def fill_variables(content, variables):
    for variable, value in variables.items():
        placeholder = "{" + variable + "}"
        content = content.replace(placeholder, value)

    return content 

def validate_email(email):
    pattern = r'^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$'
    if re.match(pattern, email):
        return True
    else:
        return False

def main(subject_template, email_body_template, signature):
    creds = None

    if os.path.exists("token.json"):
        creds = Credentials.from_authorized_user_file("token.json", SCOPES)

    if not creds or not creds.valid:
        if creds and creds.expired and creds.refresh_token:
            creds.refresh(Request())
        else:
            flow = InstalledAppFlow.from_client_secrets_file(
                "credentials.json", SCOPES
            )
            creds = flow.run_local_server(port=0)
        with open("token.json", "w") as token:
            token.write(creds.to_json())

    service = build("gmail", "v1", credentials=creds)
    serviceCal = build("calendar", "v3", credentials=creds)

    timeSlot=[]
    
    # Getting extra static variables(those which are same for all mails) if required by the template - from arguments
    if len(sys.argv) > 4:
        variables = {}
        for arg in sys.argv[4:]:
            variable, value = arg.split("=")
            variables[variable] = value.strip()
        
        if 'slot_time' in variables:
            timeSlot=convert_to_RFC3339(variables['slot_time'])

        email_body_template = fill_variables(email_body_template, variables)
        subject_template = fill_variables(subject_template, variables)

    sender = "admin@kossiitkgp.org"

    with open(csv_file, newline="") as file:
        reader = csv.DictReader(file)

        emailList=[]

        for row in reader:
            # Getting unique variables values - from the CSV file
            required_columns = set([column for variables in variable_column_mapping.values() for column in variables if column in row])

            variables = {}
            for variable, columns in variable_column_mapping.items():
                for column in columns:
                    if column in required_columns:
                        variables[variable] = row.get(column, "").strip()
                        break
                    
            email = variables['email'].strip()

            if not validate_email(email):
                print(f'Invalid mail provided: {email}')
                continue

            emailList.append(email)

    # calendar invites cannot have personalised details
    email_body = email_body_template 
    subject = subject_template

    email_content = email_body + signature

    event_obj = create_event(sender,emailList,subject,email_content,timeSlot,hasMeet)
    send_event(serviceCal,event_obj)

    print("Script execution completed.")

if __name__ == "__main__":
    main(subject_template, email_body_template, signature)