[v11,2/3] devtools: script to send notifications of expired symbols

diff --git a/devtools/notify-symbol-maintainers.py b/devtools/notify-symbol-maintainers.py
new file mode 100755
index 0000000000..edf330f88b
--- /dev/null
+++ b/devtools/notify-symbol-maintainers.py
@@ -0,0 +1,302 @@ 
+#!/usr/bin/env python3
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright(c) 2021 Intel Corporation
+# pylint: disable=invalid-name
+'''Tool to notify maintainers of expired symbols'''
+import os
+import smtplib
+import ssl
+import sys
+import subprocess
+import argparse
+from argparse import RawTextHelpFormatter
+import time
+from email.message import EmailMessage
+from pathlib import Path
+
+DESCRIPTION = '''
+Use this script with the output of the DPDK symbol tool, to notify maintainers
+and contributors of expired symbols by email. You need to define the environment
+variable DPDK_GETMAINTAINER_PATH for this tool to work.
+
+Use terminal output to review the emails before sending.
+e.g.
+$ devtools/symbol-tool.py list-expired --format-output csv \\
+| DPDK_GETMAINTAINER_PATH=<somewhere>/get_maintainer.pl \\
+{s} --format-output terminal
+
+Then use email output to send the emails to the maintainers.
+e.g.
+$ devtools/symbol-tool.py list-expired --format-output csv \\
+| DPDK_GETMAINTAINER_PATH=<somewhere>/get_maintainer.pl \\
+{s} --format-output email \\
+--smtp-server <server> --sender <someone@somewhere.com> --password <password> \\
+--cc <someone@somewhere.com>
+'''  # noqa: E501
+
+EMAIL_TEMPLATE = '''Hi there,
+
+Please note the symbols listed below have expired. In line with the DPDK ABI
+policy, they should be scheduled for removal, in the next DPDK release.
+
+For more information, please see the DPDK ABI Policy, section 3.5.3.
+https://doc.dpdk.org/guides/contributing/abi_policy.html
+
+Thanks,
+
+The DPDK Symbol Bot
+
+'''  # noqa: E501
+
+ABI_POLICY = 'doc/guides/contributing/abi_policy.rst'
+DPDK_GMP_ENV_VAR = 'DPDK_GETMAINTAINER_PATH'
+MAINTAINERS = 'MAINTAINERS'
+get_maintainer = ['devtools/get-maintainer.sh',
+                  '--email', '-f']
+
+
+class EnvironException(Exception):
+    '''Subclass exception for Pylint\'s happiness.'''
+
+
+def _die_on_exception(e):
+    '''Print an exception, and quit'''
+
+    print('Fatal Error: ' + str(e))
+    sys.exit()
+
+
+def _check_get_maintainers_env():
+    '''Check get maintainers scripts are setup'''
+
+    if not Path(get_maintainer[0]).is_file():
+        raise EnvironException('Cannot locate DPDK\'s get maintainers script, '
+                               ' usually at $' + get_maintainer[0] + '.')
+
+    if DPDK_GMP_ENV_VAR not in os.environ:
+        raise EnvironException(DPDK_GMP_ENV_VAR + ' is not defined.')
+
+    if not Path(os.environ[DPDK_GMP_ENV_VAR]).is_file():
+        raise EnvironException('Cannot locate get maintainers script, usually'
+                               ' at ' + DPDK_GMP_ENV_VAR + '.')
+
+
+def _get_maintainers(libpath):
+    '''Get the maintainers for given library'''
+
+    try:
+        _check_get_maintainers_env()
+    except EnvironException as e:
+        _die_on_exception(e)
+
+    try:
+        cmd = get_maintainer + [libpath]
+        result = subprocess.run(cmd,
+                                stdout=subprocess.PIPE,
+                                stderr=subprocess.PIPE,
+                                check=True)
+    except subprocess.CalledProcessError as e:
+        _die_on_exception(e)
+
+    if result is None:
+        return None
+
+    email = result.stdout.decode('utf-8')
+    if email == '':
+        return None
+
+    email = list(filter(None, email.split('\n')))
+    return email
+
+
+default_maintainers = _get_maintainers(ABI_POLICY) + \
+    _get_maintainers(MAINTAINERS)
+
+
+def get_maintainers(libpath):
+    '''Get the maintainers for given library'''
+    maintainers = _get_maintainers(libpath)
+
+    if maintainers is None:
+        maintainers = default_maintainers
+
+    return maintainers
+
+
+def get_message(library, symbols, config):
+    '''Build email message from symbols, config and maintainers'''
+    contributors = {}
+    message = {}
+    maintainers = get_maintainers(library)
+
+    if maintainers != default_maintainers:
+        message['CC'] = default_maintainers.copy()
+
+    if 'CC' in config:
+        message.setdefault('CC', []).append(config['CC'])
+
+    message['Subject'] = 'Expired symbols in {}\n'.format(library)
+
+    body = EMAIL_TEMPLATE
+    body += '{:<50}{:<25}{:<25}\n'.format('Symbol', 'Contributor', 'Email')
+    for sym in symbols:
+        body += ('{:<50}{:<25}{:<25}\n'.format(sym,
+                                               symbols[sym]['name'],
+                                               symbols[sym]['email']))
+        email = symbols[sym]['email']
+        contributors[email] = ''
+
+    contributors = list(contributors.keys())
+
+    message['To'] = maintainers + contributors
+    message['Body'] = body
+
+    return message
+
+
+class OutputEmail():
+    '''Format the output for email'''
+
+    def __init__(self, config):
+        self.config = config
+
+        self.terminal = OutputTerminal(config)
+        context = ssl.create_default_context()
+
+        # Try to log in to server and send email
+        try:
+            self.server = smtplib.SMTP(config['smtp_server'], 587)
+            self.server.starttls(context=context)  # Secure the connection
+            self.server.login(config['sender'], config['password'])
+        except EnvironException as e:
+            _die_on_exception(e)
+
+    def message(self, message):
+        '''send email'''
+        self.terminal.message(message)
+
+        msg = EmailMessage()
+        msg.set_content(message.pop('Body'))
+
+        for key in message.keys():
+            msg[key] = message[key]
+
+        msg['From'] = self.config['sender']
+        msg['Reply-To'] = 'no-reply@dpdk.org'
+
+        self.server.send_message(msg)
+
+        time.sleep(1)
+
+    def __del__(self):
+        self.server.quit()
+
+
+class OutputTerminal():  # pylint: disable=too-few-public-methods
+    '''Format the output for the terminal'''
+
+    def __init__(self, config):
+        self.config = config
+
+    def message(self, message):
+        '''Print email to terminal'''
+
+        terminal = 'To:' + ', '.join(message['To']) + '\n'
+        if 'sender' in self.config.keys():
+            terminal += 'From:' + self.config['sender'] + '\n'
+
+        terminal += 'Reply-To:' + 'no-reply@dpdk.org' + '\n'
+
+        if 'CC' in message:
+            terminal += 'CC:' + ', '.join(message['CC']) + '\n'
+
+        terminal += 'Subject:' + message['Subject'] + '\n'
+        terminal += 'Body:' + message['Body'] + '\n'
+
+        print(terminal)
+        print('-' * 80)
+
+
+def parse_config(args):
+    '''put the command line args in the right places'''
+    config = {}
+    error_msg = None
+
+    outputs = {
+        None: OutputTerminal,
+        'terminal': OutputTerminal,
+        'email': OutputEmail
+    }
+
+    if args.format_output == 'email':
+        if args.smtp_server is None:
+            error_msg = 'SMTP server'
+        else:
+            config['smtp_server'] = args.smtp_server
+
+        if args.sender is None:
+            error_msg = 'sender'
+        else:
+            config['sender'] = args.sender
+
+        if args.password is None:
+            error_msg = 'password'
+        else:
+            config['password'] = args.password
+
+    if args.cc is not None:
+        config['CC'] = args.cc
+
+    if error_msg is not None:
+        print('Please specify a {} for email output'.format(error_msg))
+        return None
+
+    config['output'] = outputs[args.format_output]
+    return config
+
+
+def main():
+    '''Main entry point'''
+    parser = \
+        argparse.ArgumentParser(description=DESCRIPTION.format(s=__file__),
+                                formatter_class=RawTextHelpFormatter)
+    parser.add_argument('--format-output',
+                        choices=['terminal', 'email'],
+                        default='terminal')
+    parser.add_argument('--smtp-server')
+    parser.add_argument('--password')
+    parser.add_argument('--sender')
+    parser.add_argument('--cc')
+
+    args = parser.parse_args()
+    config = parse_config(args)
+    if config is None:
+        return
+
+    symbols = {}
+    lastlib = library = ''
+
+    output = config['output'](config)
+
+    for line in sys.stdin:
+        line = line.rstrip('\n')
+
+        if line.find('mapfile') >= 0:
+            continue
+        library, symbol, name, email = line.split(',')
+
+        if library != lastlib:
+            message = get_message(lastlib, symbols, config)
+            output.message(message)
+            symbols = {}
+
+        lastlib = library
+        symbols[symbol] = {'name': name, 'email': email}
+
+    # print the last library
+    message = get_message(lastlib, symbols, config)
+    output.message(message)
+
+
+if __name__ == '__main__':
+    main()