hgext/hooklib/changeset_published.py

interfaces: introduce and use a protocol class for the `charencoding` module

See f2832de2a46c for details when this was done for the `bdiff` module.

This lets us dump the hack where the `pure` implementation was imported during
the type checking phase to provide signatures for the module methods it
provides.  Now the protocol classes are starting to shine, because these methods
are provided by `pure.charencoding` and `cext.parsers`, and references to
`cffi.charencoding` and `cext.charencoding` are forwarded to them as appropriate
by the `policy` module.  But none of that matters, as long as the module
returned provides the listed methods.

The interface was copy/pasted from the `pure` module, but `jsonescapeu8fallback`
is omitted because it is accessed from the `pure` module directly when the
escaping fails in the primary module's `jsonescapeu8()`.

# Copyright 2020 Joerg Sonnenberger <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""changeset_published is a hook to send a mail when an
existing draft changeset is moved to the public phase.

Correct message threading requires the same messageidseed to be used for both
the original notification and the new mail.

Usage:
  [notify]
  messageidseed = myseed

  [hooks]
  txnclose-phase.changeset_published = \
    python:hgext.hooklib.changeset_published.hook
"""

from __future__ import annotations

import email.errors as emailerrors
import email.utils as emailutils

from mercurial.i18n import _
from mercurial import (
    encoding,
    error,
    formatter,
    logcmdutil,
    mail,
    pycompat,
    registrar,
)
from mercurial.utils import (
    dateutil,
    stringutil,
)
from .. import notify

configtable = {}
configitem = registrar.configitem(configtable)

configitem(
    b'notify_published',
    b'domain',
    default=None,
)
configitem(
    b'notify_published',
    b'messageidseed',
    default=None,
)
configitem(
    b'notify_published',
    b'template',
    default=b'''Subject: changeset published

This changeset has been published.
''',
)


def _report_commit(ui, repo, ctx):
    domain = ui.config(b'notify_published', b'domain') or ui.config(
        b'notify', b'domain'
    )
    messageidseed = ui.config(
        b'notify_published', b'messageidseed'
    ) or ui.config(b'notify', b'messageidseed')
    template = ui.config(b'notify_published', b'template')
    spec = formatter.literal_templatespec(template)
    templater = logcmdutil.changesettemplater(ui, repo, spec)
    ui.pushbuffer()
    n = notify.notifier(ui, repo, b'incoming')

    subs = set()
    for sub, spec in n.subs:
        if spec is None:
            subs.add(sub)
            continue
        revs = repo.revs(b'%r and %d:', spec, ctx.rev())
        if len(revs):
            subs.add(sub)
            continue
    if len(subs) == 0:
        ui.debug(
            b'notify_published: no subscribers to selected repo and revset\n'
        )
        return

    templater.show(
        ctx,
        changes=ctx.changeset(),
        baseurl=ui.config(b'web', b'baseurl'),
        root=repo.root,
        webroot=n.root,
    )
    data = ui.popbuffer()

    try:
        msg = mail.parsebytes(data)
    except emailerrors.MessageParseError as inst:
        raise error.Abort(stringutil.forcebytestr(inst))

    msg['In-reply-to'] = notify.messageid(ctx, domain, messageidseed)
    msg['Message-Id'] = notify.messageid(
        ctx, domain, messageidseed + b'-published'
    )
    msg['Date'] = encoding.strfromlocal(
        dateutil.datestr(format=b"%a, %d %b %Y %H:%M:%S %1%2")
    )
    if not msg['From']:
        sender = ui.config(b'email', b'from') or ui.username()
        if b'@' not in sender or b'@localhost' in sender:
            sender = n.fixmail(sender)
        msg['From'] = mail.addressencode(ui, sender, n.charsets, n.test)
    msg['To'] = ', '.join(sorted(subs))

    msgtext = msg.as_bytes()
    if ui.configbool(b'notify', b'test'):
        ui.write(msgtext)
        if not msgtext.endswith(b'\n'):
            ui.write(b'\n')
    else:
        ui.status(_(b'notify_published: sending mail for %d\n') % ctx.rev())
        mail.sendmail(
            ui, emailutils.parseaddr(msg['From'])[1], subs, msgtext, mbox=n.mbox
        )


def hook(ui, repo, hooktype, node=None, **kwargs):
    if hooktype != b"txnclose-phase":
        raise error.Abort(
            _(b'Unsupported hook type %r') % pycompat.bytestr(hooktype)
        )
    ctx = repo.unfiltered()[node]
    if kwargs['oldphase'] == b'draft' and kwargs['phase'] == b'public':
        _report_commit(ui, repo, ctx)