"""Copyright 2018 Google LLC

Licensed under the Apache License, Version 2.0 (the "License");

you may not use this file except in compliance with the License.

You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software

distributed under the License is distributed on an "AS IS" BASIS,

WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

See the License for the specific language governing permissions and

limitations under the License.

"""

# [START gmail_show_chatty_threads]

from __future__ import print_function

import google.auth

from googleapiclient.discovery import build

from googleapiclient.errors import HttpError

def show_chatty_threads():

"""Display threads with long conversations(>= 3 messages)

Return: None

Load pre-authorized user credentials from the environment.

TODO(developer) - See https://developers.google.com/identity

for guides on implementing OAuth2 for the application.

"""

creds, _ = google.auth.default()

try:

# create gmail api client

service = build('gmail', 'v1', credentials=creds)

# pylint: disable=maybe-no-member

threads = service.users().threads().list(userId='me').execute().get('threads', [])

for thread in threads:

tdata = service.users().threads().get(userId='me', id=thread['id']).execute()

nmsgs = len(tdata['messages'])

# skip if <3 msgs in thread

if nmsgs > 2:

msg = tdata['messages'][0]['payload']

subject = ''

for header in msg['headers']:

if header['name'] == 'Subject':

subject = header['value']

break

if subject: # skip if no Subject line

print(F'- {subject}, {nmsgs}')

except HttpError as error:

print(F'An error occurred: {error}')

if __name__ == '__main__':

show_chatty_threads()

# [END gmail_show_chatty_threads]