view tests/dummysmtpd.py @ 52285:94cf83d9a2c9

sslutil: drop support for Python prior to 3.7

There's also a block of code around line 47 related to `ssl.HAS_TLSv1` to
determine the supported protocols that references "Python 3.7", but I'm not
altering that because the commit referenced there wasn't landed until just prior
to the 3.9 release, and I'm not sure what flavors of py38 might not have a
backport.

Avoid de-indenting for now for a clearer text diff.

#!/usr/bin/env python

"""dummy SMTP server for use in tests"""


import io
import optparse
import os
import socket
import ssl
import sys

from mercurial import (
    pycompat,
    server,
    sslutil,
    ui as uimod,
)

if pycompat.iswindows:
    sys.stdout = io.TextIOWrapper(
        sys.stdout.buffer,
        sys.stdout.encoding,
        sys.stdout.errors,
        newline="\n",
    )

if os.environ.get('HGIPV6', '0') == '1':
    family = socket.AF_INET6
else:
    family = socket.AF_INET


def log(msg):
    sys.stdout.write(msg)
    sys.stdout.flush()


def mocksmtpserversession(conn, addr):
    conn.send(b'220 smtp.example.com ESMTP\r\n')

    try:
        # Newer versions of OpenSSL raise on EOF
        line = conn.recv(1024)
    except ssl.SSLError:
        log('no hello: EOF\n')
        return

    if not line.lower().startswith(b'ehlo '):
        # Older versions of OpenSSl don't raise
        log('no hello: %s\n' % line)
        return

    conn.send(b'250 Hello\r\n')

    line = conn.recv(1024)
    if not line.lower().startswith(b'mail from:'):
        log('no mail from: %s\n' % line)
        return
    mailfrom = line[10:].decode().rstrip()
    if mailfrom.startswith('<') and mailfrom.endswith('>'):
        mailfrom = mailfrom[1:-1]

    conn.send(b'250 Ok\r\n')

    rcpttos = []
    while True:
        line = conn.recv(1024)
        if not line.lower().startswith(b'rcpt to:'):
            break
        rcptto = line[8:].decode().rstrip()
        if rcptto.startswith('<') and rcptto.endswith('>'):
            rcptto = rcptto[1:-1]
        rcpttos.append(rcptto)

        conn.send(b'250 Ok\r\n')

    if not line.lower().strip() == b'data':
        log('no rcpt to or data: %s' % line)

    conn.send(b'354 Go ahead\r\n')

    data = b''
    while True:
        line = conn.recv(1024)
        if not line:
            log('connection closed before end of data')
            break
        data += line
        if data.endswith(b'\r\n.\r\n'):
            data = data[:-5]
            break

    conn.send(b'250 Ok\r\n')

    log(
        '%s from=%s to=%s\n%s\n'
        % (addr[0], mailfrom, ', '.join(rcpttos), data.decode())
    )


def run(host, port, certificate):
    ui = uimod.ui.load()
    with socket.socket(family, socket.SOCK_STREAM) as s:
        s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
        s.bind((host, port))
        # log('listening at %s:%d\n' % (host, port))
        s.listen(1)
        try:
            while True:
                conn, addr = s.accept()
                if certificate:
                    try:
                        conn = sslutil.wrapserversocket(
                            conn, ui, certfile=certificate
                        )
                    except ssl.SSLError as e:
                        log('%s ssl error: %s\n' % (addr[0], e))
                        conn.close()
                        continue
                log("connection from %s:%s\n" % addr)
                mocksmtpserversession(conn, addr)
                conn.close()
        except KeyboardInterrupt:
            pass


def _encodestrsonly(v):
    if isinstance(v, type(u'')):
        return v.encode('ascii')
    return v


def bytesvars(obj):
    unidict = vars(obj)
    bd = {k.encode('ascii'): _encodestrsonly(v) for k, v in unidict.items()}
    if bd[b'daemon_postexec'] is not None:
        bd[b'daemon_postexec'] = [
            _encodestrsonly(v) for v in bd[b'daemon_postexec']
        ]
    return bd


def main():
    op = optparse.OptionParser()
    op.add_option('-d', '--daemon', action='store_true')
    op.add_option('--daemon-postexec', action='append')
    op.add_option('-p', '--port', type=int, default=8025)
    op.add_option('-a', '--address', default='localhost')
    op.add_option('--pid-file', metavar='FILE')
    op.add_option('--tls', choices=['none', 'smtps'], default='none')
    op.add_option('--certificate', metavar='FILE')
    op.add_option('--logfile', metavar='FILE')

    opts, args = op.parse_args()
    if (opts.tls == 'smtps') != bool(opts.certificate):
        op.error('--certificate must be specified with --tls=smtps')

    server.runservice(
        bytesvars(opts),
        runfn=lambda: run(opts.address, opts.port, opts.certificate),
        runargs=[pycompat.sysexecutable, pycompat.fsencode(__file__)]
        + pycompat.sysargv[1:],
        logfile=opts.logfile,
    )


if __name__ == '__main__':
    main()