view hgext/zeroconf/__init__.py @ 50310:4c1061b3e55a stable

transaction: allow to backup file that already have an offset

This will be useful in the next changeset to deal with rolling back the split of
inline revlog on transaction failure.

This involve deeper change to the transaction logic as we need to make sure we
restore the backup -before- the truncation step. Otherwise, the truncation
would act on the wrong file and be overwritten by the backup restoration later.

# zeroconf.py - zeroconf support for Mercurial
#
# Copyright 2005-2007 Olivia Mackall <[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.
'''discover and advertise repositories on the local network

The zeroconf extension will advertise :hg:`serve` instances over
DNS-SD so that they can be discovered using the :hg:`paths` command
without knowing the server's IP address.

To allow other people to discover your repository using run
:hg:`serve` in your repository::

  $ cd test
  $ hg serve

You can discover Zeroconf-enabled repositories by running
:hg:`paths`::

  $ hg paths
  zc-test = http://example.com:8000/test
'''

import os
import socket
import time

from . import Zeroconf
from mercurial import (
    dispatch,
    encoding,
    extensions,
    hg,
    pycompat,
    rcutil,
    ui as uimod,
)
from mercurial.hgweb import server as servermod

# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = b'ships-with-hg-core'

# publish

server = None
localip = None


def getip():
    # finds external-facing interface without sending any packets (Linux)
    try:
        s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
        s.connect(('1.0.0.1', 0))
        ip = s.getsockname()[0]
        return ip
    except socket.error:
        pass

    # Generic method, sometimes gives useless results
    try:
        dumbip = socket.gethostbyaddr(socket.gethostname())[2][0]
        if ':' in dumbip:
            dumbip = '127.0.0.1'
        if not dumbip.startswith('127.'):
            return dumbip
    except (socket.gaierror, socket.herror):
        dumbip = '127.0.0.1'

    # works elsewhere, but actually sends a packet
    try:
        s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
        s.connect(('1.0.0.1', 1))
        ip = s.getsockname()[0]
        return ip
    except socket.error:
        pass

    return dumbip


def publish(name, desc, path, port):
    global server, localip
    if not server:
        ip = getip()
        if ip.startswith('127.'):
            # if we have no internet connection, this can happen.
            return
        localip = socket.inet_aton(ip)
        server = Zeroconf.Zeroconf(ip)

    hostname = socket.gethostname().split('.')[0]
    host = hostname + ".local"
    name = "%s-%s" % (hostname, name)

    # advertise to browsers
    svc = Zeroconf.ServiceInfo(
        b'_http._tcp.local.',
        pycompat.bytestr(name + '._http._tcp.local.'),
        server=host,
        port=port,
        properties={b'description': desc, b'path': b"/" + path},
        address=localip,
        weight=0,
        priority=0,
    )
    server.registerService(svc)

    # advertise to Mercurial clients
    svc = Zeroconf.ServiceInfo(
        b'_hg._tcp.local.',
        pycompat.bytestr(name + '._hg._tcp.local.'),
        server=host,
        port=port,
        properties={b'description': desc, b'path': b"/" + path},
        address=localip,
        weight=0,
        priority=0,
    )
    server.registerService(svc)


def zc_create_server(create_server, ui, app):
    httpd = create_server(ui, app)
    port = httpd.port

    try:
        repos = app.repos
    except AttributeError:
        # single repo
        with app._obtainrepo() as repo:
            name = app.reponame or os.path.basename(repo.root)
            path = repo.ui.config(b"web", b"prefix", b"").strip(b'/')
            desc = repo.ui.config(b"web", b"description")
            if not desc:
                desc = name
        publish(name, desc, path, port)
    else:
        # webdir
        prefix = app.ui.config(b"web", b"prefix", b"").strip(b'/') + b'/'
        for repo, path in repos:
            u = app.ui.copy()
            if rcutil.use_repo_hgrc():
                u.readconfig(os.path.join(path, b'.hg', b'hgrc'))
            name = os.path.basename(repo)
            path = (prefix + repo).strip(b'/')
            desc = u.config(b'web', b'description')
            if not desc:
                desc = name
            publish(name, desc, path, port)
    return httpd


# listen


class listener:
    def __init__(self):
        self.found = {}

    def removeService(self, server, type, name):
        if repr(name) in self.found:
            del self.found[repr(name)]

    def addService(self, server, type, name):
        self.found[repr(name)] = server.getServiceInfo(type, name)


def getzcpaths():
    ip = getip()
    if ip.startswith('127.'):
        return
    server = Zeroconf.Zeroconf(ip)
    l = listener()
    Zeroconf.ServiceBrowser(server, b"_hg._tcp.local.", l)
    time.sleep(1)
    server.close()
    for value in l.found.values():
        name = value.name[: value.name.index(b'.')]
        url = "http://%s:%s%s" % (
            socket.inet_ntoa(value.address),
            value.port,
            value.properties.get("path", "/"),
        )
        yield b"zc-" + name, pycompat.bytestr(url)


def config(orig, self, section, key, *args, **kwargs):
    if section == b"paths" and key.startswith(b"zc-"):
        for name, path in getzcpaths():
            if name == key:
                return path
    return orig(self, section, key, *args, **kwargs)


def configitems(orig, self, section, *args, **kwargs):
    repos = orig(self, section, *args, **kwargs)
    if section == b"paths":
        repos += getzcpaths()
    return repos


def configsuboptions(orig, self, section, name, *args, **kwargs):
    opt, sub = orig(self, section, name, *args, **kwargs)
    if section == b"paths" and name.startswith(b"zc-"):
        # We have to find the URL in the zeroconf paths.  We can't cons up any
        # suboptions, so we use any that we found in the original config.
        for zcname, zcurl in getzcpaths():
            if zcname == name:
                return zcurl, sub
    return opt, sub


def defaultdest(orig, source):
    for name, path in getzcpaths():
        if path == source:
            return name.encode(encoding.encoding)
    return orig(source)


def cleanupafterdispatch(orig, ui, options, cmd, cmdfunc):
    try:
        return orig(ui, options, cmd, cmdfunc)
    finally:
        # we need to call close() on the server to notify() the various
        # threading Conditions and allow the background threads to exit
        global server
        if server:
            server.close()


extensions.wrapfunction(dispatch, b'_runcommand', cleanupafterdispatch)

extensions.wrapfunction(uimod.ui, b'config', config)
extensions.wrapfunction(uimod.ui, b'configitems', configitems)
extensions.wrapfunction(uimod.ui, b'configsuboptions', configsuboptions)
extensions.wrapfunction(hg, b'defaultdest', defaultdest)
extensions.wrapfunction(servermod, b'create_server', zc_create_server)