view hgext/blackbox.py @ 23637:13f53a2aa342

merge: write manifestmerge() using dictionary with entry per file

In the same vein as 38e55e55ae4d (largefiles: rewrite merge code using
dictionary with entry per file, 2014-12-09), rewrite manifestmerge()
itself as dictionary with the filename as key. This will let us
simplify some of the other code in merge.py and eventually drop the
conversion in the largefiles code.

No difference in speed could be detected (well within the noise level
when run in Mozilla repo).

# blackbox.py - log repository events to a file for post-mortem debugging
#
# Copyright 2010 Nicolas Dumazet
# Copyright 2013 Facebook, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

"""log repository events to a blackbox for debugging

Logs event information to .hg/blackbox.log to help debug and diagnose problems.
The events that get logged can be configured via the blackbox.track config key.
Examples::

  [blackbox]
  track = *

  [blackbox]
  track = command, commandfinish, commandexception, exthook, pythonhook

  [blackbox]
  track = incoming

  [blackbox]
  # limit the size of a log file
  maxsize = 1.5 MB
  # rotate up to N log files when the current one gets too big
  maxfiles = 3

"""

from mercurial import util, cmdutil
from mercurial.i18n import _
import errno, os, re

cmdtable = {}
command = cmdutil.command(cmdtable)
testedwith = 'internal'
lastblackbox = None

def wrapui(ui):
    class blackboxui(ui.__class__):
        @util.propertycache
        def track(self):
            return self.configlist('blackbox', 'track', ['*'])

        def _openlogfile(self):
            def rotate(oldpath, newpath):
                try:
                    os.unlink(newpath)
                except OSError, err:
                    if err.errno != errno.ENOENT:
                        self.debug("warning: cannot remove '%s': %s\n" %
                                   (newpath, err.strerror))
                try:
                    if newpath:
                        os.rename(oldpath, newpath)
                except OSError, err:
                    if err.errno != errno.ENOENT:
                        self.debug("warning: cannot rename '%s' to '%s': %s\n" %
                                   (newpath, oldpath, err.strerror))

            fp = self._bbopener('blackbox.log', 'a')
            maxsize = self.configbytes('blackbox', 'maxsize', 1048576)
            if maxsize > 0:
                st = os.fstat(fp.fileno())
                if st.st_size >= maxsize:
                    path = fp.name
                    fp.close()
                    maxfiles = self.configint('blackbox', 'maxfiles', 7)
                    for i in xrange(maxfiles - 1, 1, -1):
                        rotate(oldpath='%s.%d' % (path, i - 1),
                               newpath='%s.%d' % (path, i))
                    rotate(oldpath=path,
                           newpath=maxfiles > 0 and path + '.1')
                    fp = self._bbopener('blackbox.log', 'a')
            return fp

        def log(self, event, *msg, **opts):
            global lastblackbox
            super(blackboxui, self).log(event, *msg, **opts)

            if not '*' in self.track and not event in self.track:
                return

            if util.safehasattr(self, '_blackbox'):
                blackbox = self._blackbox
            elif util.safehasattr(self, '_bbopener'):
                try:
                    self._blackbox = self._openlogfile()
                except (IOError, OSError), err:
                    self.debug('warning: cannot write to blackbox.log: %s\n' %
                               err.strerror)
                    del self._bbopener
                    self._blackbox = None
                blackbox = self._blackbox
            else:
                # certain ui instances exist outside the context of
                # a repo, so just default to the last blackbox that
                # was seen.
                blackbox = lastblackbox

            if blackbox:
                date = util.datestr(None, '%Y/%m/%d %H:%M:%S')
                user = util.getuser()
                formattedmsg = msg[0] % msg[1:]
                try:
                    blackbox.write('%s %s> %s' % (date, user, formattedmsg))
                except IOError, err:
                    self.debug('warning: cannot write to blackbox.log: %s\n' %
                               err.strerror)
                lastblackbox = blackbox

        def setrepo(self, repo):
            self._bbopener = repo.opener

    ui.__class__ = blackboxui

def uisetup(ui):
    wrapui(ui)

def reposetup(ui, repo):
    # During 'hg pull' a httppeer repo is created to represent the remote repo.
    # It doesn't have a .hg directory to put a blackbox in, so we don't do
    # the blackbox setup for it.
    if not repo.local():
        return

    if util.safehasattr(ui, 'setrepo'):
        ui.setrepo(repo)

@command('^blackbox',
    [('l', 'limit', 10, _('the number of events to show')),
    ],
    _('hg blackbox [OPTION]...'))
def blackbox(ui, repo, *revs, **opts):
    '''view the recent repository events
    '''

    if not os.path.exists(repo.join('blackbox.log')):
        return

    limit = opts.get('limit')
    blackbox = repo.opener('blackbox.log', 'r')
    lines = blackbox.read().split('\n')

    count = 0
    output = []
    for line in reversed(lines):
        if count >= limit:
            break

        # count the commands by matching lines like: 2013/01/23 19:13:36 root>
        if re.match('^\d{4}/\d{2}/\d{2} \d{2}:\d{2}:\d{2} .*> .*', line):
            count += 1
        output.append(line)

    ui.status('\n'.join(reversed(output)))