view hgext/zeroconf/__init__.py @ 27586:42910f9fffeb

revset: use delayregistrar to register predicate in extension easily

Previous patch introduced 'revset.predicate' decorator to register
revset predicate function easily.

But it shouldn't be used in extension directly, because it registers
specified function immediately. Registration itself can't be restored,
even if extension loading fails after that.

Therefore, registration should be delayed until 'uisetup()' or so.

This patch uses 'extpredicate' decorator derived from 'delayregistrar'
to register predicate in extension easily.

This patch also tests whether 'registrar.delayregistrar' avoids
function registration if 'setup()' isn't invoked on it, because
'extpredicate' is the first user of it.

# zeroconf.py - zeroconf support for Mercurial
#
# Copyright 2005-2007 Matt 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

Zeroconf-enabled repositories will be announced in a network without
the need to configure a server or a service. They can be discovered
without knowing their actual 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 socket, time, os

import Zeroconf
from mercurial import ui, hg, encoding, dispatch
from mercurial import extensions
from mercurial.hgweb import server as servermod

# Note for extension authors: ONLY specify testedwith = 'internal' 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 = 'internal'

# 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 not dumbip.startswith('127.') and ':' not in dumbip:
            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('_http._tcp.local.',
                               name + '._http._tcp.local.',
                               server = host,
                               port = port,
                               properties = {'description': desc,
                                             'path': "/" + path},
                               address = localip, weight = 0, priority = 0)
    server.registerService(svc)

    # advertise to Mercurial clients
    svc = Zeroconf.ServiceInfo('_hg._tcp.local.',
                               name + '._hg._tcp.local.',
                               server = host,
                               port = port,
                               properties = {'description': desc,
                                             'path': "/" + 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
        name = app.reponame or os.path.basename(app.repo.root)
        path = app.repo.ui.config("web", "prefix", "").strip('/')
        desc = app.repo.ui.config("web", "description", name)
        publish(name, desc, path, port)
    else:
        # webdir
        prefix = app.ui.config("web", "prefix", "").strip('/') + '/'
        for repo, path in repos:
            u = app.ui.copy()
            u.readconfig(os.path.join(path, '.hg', 'hgrc'))
            name = os.path.basename(repo)
            path = (prefix + repo).strip('/')
            desc = u.config('web', 'description', name)
            publish(name, desc, path, port)
    return httpd

# listen

class listener(object):
    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, "_hg._tcp.local.", l)
    time.sleep(1)
    server.close()
    for value in l.found.values():
        name = value.name[:value.name.index('.')]
        url = "http://%s:%s%s" % (socket.inet_ntoa(value.address), value.port,
                                  value.properties.get("path", "/"))
        yield "zc-" + name, url

def config(orig, self, section, key, default=None, untrusted=False):
    if section == "paths" and key.startswith("zc-"):
        for name, path in getzcpaths():
            if name == key:
                return path
    return orig(self, section, key, default, untrusted)

def configitems(orig, self, section, untrusted=False):
    repos = orig(self, section, untrusted)
    if section == "paths":
        repos += getzcpaths()
    return repos

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, '_runcommand', cleanupafterdispatch)

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