# httppeer.py - HTTP repository proxy classes for mercurial

#

# Copyright 2005, 2006 Matt Mackall <mpm@selenic.com>

# Copyright 2006 Vadim Gelfer <vadim.gelfer@gmail.com>

#

# This software may be used and distributed according to the terms of the

# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

import errno

import httplib

import os

import socket

import tempfile

import urllib

import urllib2

import zlib

from .i18n import _

from .node import nullid

from . import (

    changegroup,

    error,

    httpconnection,

    statichttprepo,

    url,

    util,

    wireproto,

)

def zgenerator(f):

    zd = zlib.decompressobj()

    try:

        for chunk in util.filechunkiter(f):

            while chunk:

                yield zd.decompress(chunk, 2**18)

                chunk = zd.unconsumed_tail

    except httplib.HTTPException:

        raise IOError(None, _('connection ended unexpectedly'))

    yield zd.flush()

class httppeer(wireproto.wirepeer):

    def __init__(self, ui, path):

        self.path = path

        self.caps = None

        self.handler = None

        self.urlopener = None

        self.requestbuilder = None

        u = util.url(path)

        if u.query or u.fragment:

            raise error.Abort(_('unsupported URL component: "%s"') %

                             (u.query or u.fragment))

        # urllib cannot handle URLs with embedded user or passwd

        self._url, authinfo = u.authinfo()

        self.ui = ui

        self.ui.debug('using %s\n' % self._url)

        self.urlopener = url.opener(ui, authinfo)

        self.requestbuilder = urllib2.Request

    def __del__(self):

        if self.urlopener:

            for h in self.urlopener.handlers:

                h.close()

                getattr(h, "close_all", lambda : None)()

    def url(self):

        return self.path

    # look up capabilities only when needed

    def _fetchcaps(self):

        self.caps = set(self._call('capabilities').split())

    def _capabilities(self):

        if self.caps is None:

            try:

                self._fetchcaps()

            except error.RepoError:

                self.caps = set()

            self.ui.debug('capabilities: %s\n' %

                          (' '.join(self.caps or ['none'])))

        return self.caps

    def lock(self):

        raise error.Abort(_('operation not supported over http'))

    def _callstream(self, cmd, **args):

        if cmd == 'pushkey':

            args['data'] = ''

        data = args.pop('data', None)

        size = 0

        if util.safehasattr(data, 'length'):

            size = data.length

        elif data is not None:

            size = len(data)

        headers = args.pop('headers', {})

        if data is not None and 'Content-Type' not in headers:

            headers['Content-Type'] = 'application/mercurial-0.1'

        if size and self.ui.configbool('ui', 'usehttp2', False):

            headers['Expect'] = '100-Continue'

            headers['X-HgHttp2'] = '1'

        self.ui.debug("sending %s command\n" % cmd)

        q = [('cmd', cmd)]

        headersize = 0

        if len(args) > 0:

            httpheader = self.capable('httpheader')

            if httpheader:

                headersize = int(httpheader.split(',')[0])

        if headersize > 0:

            # The headers can typically carry more data than the URL.

            encargs = urllib.urlencode(sorted(args.items()))

            headerfmt = 'X-HgArg-%s'

            contentlen = headersize - len(headerfmt % '000' + ': \r\n')

            headernum = 0

            for i in xrange(0, len(encargs), contentlen):

                headernum += 1

                header = headerfmt % str(headernum)

                headers[header] = encargs[i:i + contentlen]

            varyheaders = [headerfmt % str(h) for h in range(1, headernum + 1)]

            headers['Vary'] = ','.join(varyheaders)

        else:

            q += sorted(args.items())

        qs = '?%s' % urllib.urlencode(q)

        cu = "%s%s" % (self._url, qs)

        req = self.requestbuilder(cu, data, headers)

        if data is not None:

            self.ui.debug("sending %s bytes\n" % size)

            req.add_unredirected_header('Content-Length', '%d' % size)

        try:

            resp = self.urlopener.open(req)

        except urllib2.HTTPError as inst:

            if inst.code == 401:

                raise error.Abort(_('authorization failed'))

            raise

        except httplib.HTTPException as inst:

            self.ui.debug('http error while sending %s command\n' % cmd)

            self.ui.traceback()

            raise IOError(None, inst)

        except IndexError:

            # this only happens with Python 2.3, later versions raise URLError

            raise error.Abort(_('http error, possibly caused by proxy setting'))

        # record the url we got redirected to

        resp_url = resp.geturl()

        if resp_url.endswith(qs):

            resp_url = resp_url[:-len(qs)]

        if self._url.rstrip('/') != resp_url.rstrip('/'):

            if not self.ui.quiet:

                self.ui.warn(_('real URL is %s\n') % resp_url)

        self._url = resp_url

        try:

            proto = resp.getheader('content-type')

        except AttributeError:

            proto = resp.headers.get('content-type', '')

        safeurl = util.hidepassword(self._url)

        if proto.startswith('application/hg-error'):

            raise error.OutOfBandError(resp.read())

        # accept old "text/plain" and "application/hg-changegroup" for now

        if not (proto.startswith('application/mercurial-') or

                (proto.startswith('text/plain')

                 and not resp.headers.get('content-length')) or

                proto.startswith('application/hg-changegroup')):

            self.ui.debug("requested URL: '%s'\n" % util.hidepassword(cu))

            raise error.RepoError(

                _("'%s' does not appear to be an hg repository:\n"

                  "---%%<--- (%s)\n%s\n---%%<---\n")

                % (safeurl, proto or 'no content-type', resp.read(1024)))

        if proto.startswith('application/mercurial-'):

            try:

                version = proto.split('-', 1)[1]

                version_info = tuple([int(n) for n in version.split('.')])

            except ValueError:

                raise error.RepoError(_("'%s' sent a broken Content-Type "

                                        "header (%s)") % (safeurl, proto))

            if version_info > (0, 1):

                raise error.RepoError(_("'%s' uses newer protocol %s") %

                                      (safeurl, version))

        return resp

    def _call(self, cmd, **args):

        fp = self._callstream(cmd, **args)

        try:

            return fp.read()

        finally:

            # if using keepalive, allow connection to be reused

            fp.close()

    def _callpush(self, cmd, cg, **args):

        # have to stream bundle to a temp file because we do not have

        # http 1.1 chunked transfer.

        types = self.capable('unbundle')

        try:

            types = types.split(',')

        except AttributeError:

            # servers older than d1b16a746db6 will send 'unbundle' as a

            # boolean capability. They only support headerless/uncompressed

            # bundles.

            types = [""]

        for x in types:

            if x in changegroup.bundletypes:

                type = x

                break

        tempname = changegroup.writebundle(self.ui, cg, None, type)

        fp = httpconnection.httpsendfile(self.ui, tempname, "rb")

        headers = {'Content-Type': 'application/mercurial-0.1'}

        try:

            r = self._call(cmd, data=fp, headers=headers, **args)

            vals = r.split('\n', 1)

            if len(vals) < 2:

                raise error.ResponseError(_("unexpected response:"), r)

            return vals

        except socket.error as err:

            if err.args[0] in (errno.ECONNRESET, errno.EPIPE):

                raise error.Abort(_('push failed: %s') % err.args[1])

            raise error.Abort(err.args[1])

        finally:

            fp.close()

            os.unlink(tempname)

    def _calltwowaystream(self, cmd, fp, **args):

        fh = None

        fp_ = None

        filename = None

        try:

            # dump bundle to disk

            fd, filename = tempfile.mkstemp(prefix="hg-bundle-", suffix=".hg")

            fh = os.fdopen(fd, "wb")

            d = fp.read(4096)

            while d:

                fh.write(d)

                d = fp.read(4096)

            fh.close()

            # start http push

            fp_ = httpconnection.httpsendfile(self.ui, filename, "rb")

            headers = {'Content-Type': 'application/mercurial-0.1'}

            return self._callstream(cmd, data=fp_, headers=headers, **args)

        finally:

            if fp_ is not None:

                fp_.close()

            if fh is not None:

                fh.close()

                os.unlink(filename)

    def _callcompressable(self, cmd, **args):

        return util.chunkbuffer(zgenerator(stream))

    def _abort(self, exception):

        raise exception

class httpspeer(httppeer):

    def __init__(self, ui, path):

        if not url.has_https:

            raise error.Abort(_('Python support for SSL and HTTPS '

                               'is not installed'))

        httppeer.__init__(self, ui, path)

def instance(ui, path, create):

    if create:

        raise error.Abort(_('cannot create new http repository'))

    try:

        if path.startswith('https:'):

            inst = httpspeer(ui, path)

        else:

            inst = httppeer(ui, path)

        try:

            # Try to do useful work when checking compatibility.

            # Usually saves a roundtrip since we want the caps anyway.

            inst._fetchcaps()

        except error.RepoError:

            # No luck, try older compatibility check.

            inst.between([(nullid, nullid)])

        return inst

    except error.RepoError as httpexception:

        try:

            r = statichttprepo.instance(ui, "static-" + path, create)

            ui.note('(falling back to static-http)\n')

            return r

        except error.RepoError:

            raise httpexception # use the original http RepoError instead