1#!/usr/bin/python2
2# Copyright 2015 The Chromium OS Authors. All rights reserved.
3# Use of this source code is governed by a BSD-style license that can be
4# found in the LICENSE file.
5
6"""
7Mail the content of standard input.
8
9Example usage:
10  Use pipe:
11     $ echo "Some content" |./gmail_lib.py -s "subject" abc@bb.com xyz@gmail.com
12
13  Manually input:
14     $ ./gmail_lib.py -s "subject" abc@bb.com xyz@gmail.com
15     > Line 1
16     > Line 2
17     Ctrl-D to end standard input.
18"""
19from __future__ import absolute_import
20from __future__ import division
21from __future__ import print_function
22
23import argparse
24import base64
25import httplib2
26import logging
27import sys
28import os
29import random
30from email.mime.text import MIMEText
31
32import common
33from autotest_lib.client.bin import utils
34from autotest_lib.client.common_lib import global_config
35from autotest_lib.server import site_utils
36
37try:
38  from apiclient.discovery import build as apiclient_build
39  from apiclient import errors as apiclient_errors
40  from oauth2client import file as oauth_client_fileio
41except ImportError as e:
42  apiclient_build = None
43  logging.debug("API client for gmail disabled. %s", e)
44
45# Note: These imports needs to come after the apiclient imports, because
46# of a sys.path war between chromite and autotest crbug.com/622988
47from autotest_lib.server import utils as server_utils
48from chromite.lib import retry_util
49
50try:
51    from chromite.lib import metrics
52except ImportError:
53    metrics = utils.metrics_mock
54
55
56DEFAULT_CREDS_FILE = global_config.global_config.get_config_value(
57        'NOTIFICATIONS', 'gmail_api_credentials', default=None)
58RETRY_DELAY = 5
59RETRY_BACKOFF_FACTOR = 1.5
60MAX_RETRY = 10
61RETRIABLE_MSGS = [
62        # User-rate limit exceeded
63        r'HttpError 429',]
64
65class GmailApiException(Exception):
66    """Exception raised in accessing Gmail API."""
67
68
69class Message():
70    """An email message."""
71
72    def __init__(self, to, subject, message_text):
73        """Initialize a message.
74
75        @param to: The recievers saperated by comma.
76                   e.g. 'abc@gmail.com,xyz@gmail.com'
77        @param subject: String, subject of the message
78        @param message_text: String, content of the message.
79        """
80        self.to = to
81        self.subject = subject
82        self.message_text = message_text
83
84
85    def get_payload(self):
86        """Get the payload that can be sent to the Gmail API.
87
88        @return: A dictionary representing the message.
89        """
90        message = MIMEText(self.message_text)
91        message['to'] = self.to
92        message['subject'] = self.subject
93        return {'raw': base64.urlsafe_b64encode(message.as_string())}
94
95
96class GmailApiClient():
97    """Client that talks to Gmail API."""
98
99    def __init__(self, oauth_credentials):
100        """Init Gmail API client
101
102        @param oauth_credentials: Path to the oauth credential token.
103        """
104        if not apiclient_build:
105            raise GmailApiException('Cannot get apiclient library.')
106
107        storage = oauth_client_fileio.Storage(oauth_credentials)
108        credentials = storage.get()
109        if not credentials or credentials.invalid:
110            raise GmailApiException('Invalid credentials for Gmail API, '
111                                    'could not send email.')
112        http = credentials.authorize(httplib2.Http())
113        self._service = apiclient_build('gmail', 'v1', http=http)
114
115
116    def send_message(self, message, ignore_error=True):
117        """Send an email message.
118
119        @param message: Message to be sent.
120        @param ignore_error: If True, will ignore any HttpError.
121        """
122        try:
123            # 'me' represents the default authorized user.
124            message = self._service.users().messages().send(
125                    userId='me', body=message.get_payload()).execute()
126            logging.debug('Email sent: %s' , message['id'])
127        except apiclient_errors.HttpError as error:
128            if ignore_error:
129                logging.error('Failed to send email: %s', error)
130            else:
131                raise
132
133
134def send_email(to, subject, message_text, retry=True, creds_path=None):
135    """Send email.
136
137    @param to: The recipients, separated by comma.
138    @param subject: Subject of the email.
139    @param message_text: Text to send.
140    @param retry: If retry on retriable failures as defined in RETRIABLE_MSGS.
141    @param creds_path: The credential path for gmail account, if None,
142                       will use DEFAULT_CREDS_FILE.
143    """
144    auth_creds = server_utils.get_creds_abspath(
145        creds_path or DEFAULT_CREDS_FILE)
146    if not auth_creds or not os.path.isfile(auth_creds):
147        logging.error('Failed to send email to %s: Credential file does not '
148                      'exist: %s. If this is a prod server, puppet should '
149                      'install it. If you need to be able to send email, '
150                      'find the credential file from chromeos-admin repo and '
151                      'copy it to %s', to, auth_creds, auth_creds)
152        return
153    client = GmailApiClient(oauth_credentials=auth_creds)
154    m = Message(to, subject, message_text)
155    retry_count = MAX_RETRY if retry else 0
156
157    def _run():
158        """Send the message."""
159        client.send_message(m, ignore_error=False)
160
161    def handler(exc):
162        """Check if exc is an HttpError and is retriable.
163
164        @param exc: An exception.
165
166        @return: True if is an retriable HttpError.
167        """
168        if not isinstance(exc, apiclient_errors.HttpError):
169            return False
170
171        error_msg = str(exc)
172        should_retry = any([msg in error_msg for msg in RETRIABLE_MSGS])
173        if should_retry:
174            logging.warning('Will retry error %s', exc)
175        return should_retry
176
177    success = False
178    try:
179        retry_util.GenericRetry(
180                handler, retry_count, _run, sleep=RETRY_DELAY,
181                backoff_factor=RETRY_BACKOFF_FACTOR)
182        success = True
183    finally:
184        metrics.Counter('chromeos/autotest/send_email/count').increment(
185                fields={'success': success})
186
187
188if __name__ == '__main__':
189    logging.basicConfig(level=logging.DEBUG)
190    parser = argparse.ArgumentParser(
191            description=__doc__, formatter_class=argparse.RawTextHelpFormatter)
192    parser.add_argument('-s', '--subject', type=str, dest='subject',
193                        required=True, help='Subject of the mail')
194    parser.add_argument('-p', type=float, dest='probability',
195                        required=False, default=0,
196                        help='(optional) per-addressee probability '
197                             'with which to send email. If not specified '
198                             'all addressees will receive message.')
199    parser.add_argument('recipients', nargs='*',
200                        help='Email addresses separated by space.')
201    args = parser.parse_args()
202    if not args.recipients or not args.subject:
203        print('Requires both recipients and subject.')
204        sys.exit(1)
205
206    message_text = sys.stdin.read()
207
208    if args.probability:
209        recipients = []
210        for r in args.recipients:
211            if random.random() < args.probability:
212                recipients.append(r)
213        if recipients:
214            print('Randomly selected recipients %s' % recipients)
215        else:
216            print('Random filtering removed all recipients. Sending nothing.')
217            sys.exit(0)
218    else:
219        recipients = args.recipients
220
221
222    with site_utils.SetupTsMonGlobalState('gmail_lib', short_lived=True):
223        send_email(','.join(recipients), args.subject , message_text)
224