##// END OF EJS Templates
wireproto: define and implement protocol for issuing requests...
wireproto: define and implement protocol for issuing requests The existing HTTP and SSH wire protocols suffer from a host of flaws and shortcomings. I've been wanting to rewrite the protocol for a while now. Supporting partial clone - which will require new wire protocol commands and capabilities - and other advanced server functionality will be much easier if we start from a clean slate and don't have to be constrained by limitations of the existing wire protocol. This commit starts to introduce a new data exchange format for use over the wire protocol. The new protocol is built on top of "frames," which are atomic units of metadata + data. Frames will make it easier to implement proxies and other mechanisms that want to inspect data without having to maintain state. The existing frame metadata is very minimal and it will evolve heavily. (We will eventually support things like concurrent requests, out-of-order responses, compression, side-channels for status updates, etc. Some of these will require additions to the frame header.) Another benefit of frames is that all reads are of a fixed size. A reader works by consuming a frame header, extracting the payload length, then reading that many bytes. No lookahead, buffering, or memory reallocations are needed. The new protocol attempts to be transport agnostic. I want all that's required to use the new protocol to be a pair of unidirectional, half-duplex pipes. (Yes, we will eventually make use of full-duplex pipes, but that's for another commit.) Notably, when the SSH transport switches to this new protocol, stderr will be unused. This is by design: the lack of stderr on HTTP harms protocol behavior there. By shoehorning everything into a pair of pipes, we can have more consistent behavior across transports. We currently only define the client side parts of the new protocol, specifically the bits for requesting that a command run. This keeps the new code and feature small and somewhat easy to review. We add support to `hg debugwireproto` for writing frames into HTTP request bodies. Our tests that issue commands to the new HTTP endpoint have been updated to transmit frames. The server bits haven't been touched to consume the frames yet. This will occur in the next commit... Astute readers may notice that the command name is transmitted in both the HTTP request URL and the command request frame. This is partially a kludge from me initially implementing the frame-based protocol for SSH first. But it is also a feature: I intend to eventually support issuing multiple commands per HTTP request. This will allow us to replace the abomination that is the "batch" wire protocol command with a protocol-level mechanism for performing multi-dispatch. Because I want the frame-based protocol to be as similar as possible across transports, I'd rather we (redundantly) include the command name in the frame than differ behavior between transports that have out-of-band routing information (like HTTP) readily available. Differential Revision: https://phab.mercurial-scm.org/D2851

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progress.py
302 lines | 10.9 KiB | text/x-python | PythonLexer
# progress.py progress bars related code
#
# Copyright (C) 2010 Augie Fackler <durin42@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 threading
import time
from .i18n import _
from . import encoding
def spacejoin(*args):
return ' '.join(s for s in args if s)
def shouldprint(ui):
return not (ui.quiet or ui.plain('progress')) and (
ui._isatty(ui.ferr) or ui.configbool('progress', 'assume-tty'))
def fmtremaining(seconds):
"""format a number of remaining seconds in human readable way
This will properly display seconds, minutes, hours, days if needed"""
if seconds < 60:
# i18n: format XX seconds as "XXs"
return _("%02ds") % (seconds)
minutes = seconds // 60
if minutes < 60:
seconds -= minutes * 60
# i18n: format X minutes and YY seconds as "XmYYs"
return _("%dm%02ds") % (minutes, seconds)
# we're going to ignore seconds in this case
minutes += 1
hours = minutes // 60
minutes -= hours * 60
if hours < 30:
# i18n: format X hours and YY minutes as "XhYYm"
return _("%dh%02dm") % (hours, minutes)
# we're going to ignore minutes in this case
hours += 1
days = hours // 24
hours -= days * 24
if days < 15:
# i18n: format X days and YY hours as "XdYYh"
return _("%dd%02dh") % (days, hours)
# we're going to ignore hours in this case
days += 1
weeks = days // 7
days -= weeks * 7
if weeks < 55:
# i18n: format X weeks and YY days as "XwYYd"
return _("%dw%02dd") % (weeks, days)
# we're going to ignore days and treat a year as 52 weeks
weeks += 1
years = weeks // 52
weeks -= years * 52
# i18n: format X years and YY weeks as "XyYYw"
return _("%dy%02dw") % (years, weeks)
# file_write() and file_flush() of Python 2 do not restart on EINTR if
# the file is attached to a "slow" device (e.g. a terminal) and raise
# IOError. We cannot know how many bytes would be written by file_write(),
# but a progress text is known to be short enough to be written by a
# single write() syscall, so we can just retry file_write() with the whole
# text. (issue5532)
#
# This should be a short-term workaround. We'll need to fix every occurrence
# of write() to a terminal or pipe.
def _eintrretry(func, *args):
while True:
try:
return func(*args)
except IOError as err:
if err.errno == errno.EINTR:
continue
raise
class progbar(object):
def __init__(self, ui):
self.ui = ui
self._refreshlock = threading.Lock()
self.resetstate()
def resetstate(self):
self.topics = []
self.topicstates = {}
self.starttimes = {}
self.startvals = {}
self.printed = False
self.lastprint = time.time() + float(self.ui.config(
'progress', 'delay'))
self.curtopic = None
self.lasttopic = None
self.indetcount = 0
self.refresh = float(self.ui.config(
'progress', 'refresh'))
self.changedelay = max(3 * self.refresh,
float(self.ui.config(
'progress', 'changedelay')))
self.order = self.ui.configlist('progress', 'format')
self.estimateinterval = self.ui.configwith(
float, 'progress', 'estimateinterval')
def show(self, now, topic, pos, item, unit, total):
if not shouldprint(self.ui):
return
termwidth = self.width()
self.printed = True
head = ''
needprogress = False
tail = ''
for indicator in self.order:
add = ''
if indicator == 'topic':
add = topic
elif indicator == 'number':
if total:
add = b'%*d/%d' % (len(str(total)), pos, total)
else:
add = b'%d' % pos
elif indicator.startswith('item') and item:
slice = 'end'
if '-' in indicator:
wid = int(indicator.split('-')[1])
elif '+' in indicator:
slice = 'beginning'
wid = int(indicator.split('+')[1])
else:
wid = 20
if slice == 'end':
add = encoding.trim(item, wid, leftside=True)
else:
add = encoding.trim(item, wid)
add += (wid - encoding.colwidth(add)) * ' '
elif indicator == 'bar':
add = ''
needprogress = True
elif indicator == 'unit' and unit:
add = unit
elif indicator == 'estimate':
add = self.estimate(topic, pos, total, now)
elif indicator == 'speed':
add = self.speed(topic, pos, unit, now)
if not needprogress:
head = spacejoin(head, add)
else:
tail = spacejoin(tail, add)
if needprogress:
used = 0
if head:
used += encoding.colwidth(head) + 1
if tail:
used += encoding.colwidth(tail) + 1
progwidth = termwidth - used - 3
if total and pos <= total:
amt = pos * progwidth // total
bar = '=' * (amt - 1)
if amt > 0:
bar += '>'
bar += ' ' * (progwidth - amt)
else:
progwidth -= 3
self.indetcount += 1
# mod the count by twice the width so we can make the
# cursor bounce between the right and left sides
amt = self.indetcount % (2 * progwidth)
amt -= progwidth
bar = (' ' * int(progwidth - abs(amt)) + '<=>' +
' ' * int(abs(amt)))
prog = ''.join(('[', bar, ']'))
out = spacejoin(head, prog, tail)
else:
out = spacejoin(head, tail)
self._writeerr('\r' + encoding.trim(out, termwidth))
self.lasttopic = topic
self._flusherr()
def clear(self):
if not self.printed or not self.lastprint or not shouldprint(self.ui):
return
self._writeerr('\r%s\r' % (' ' * self.width()))
if self.printed:
# force immediate re-paint of progress bar
self.lastprint = 0
def complete(self):
if not shouldprint(self.ui):
return
if self.ui.configbool('progress', 'clear-complete'):
self.clear()
else:
self._writeerr('\n')
self._flusherr()
def _flusherr(self):
_eintrretry(self.ui.ferr.flush)
def _writeerr(self, msg):
_eintrretry(self.ui.ferr.write, msg)
def width(self):
tw = self.ui.termwidth()
return min(int(self.ui.config('progress', 'width', default=tw)), tw)
def estimate(self, topic, pos, total, now):
if total is None:
return ''
initialpos = self.startvals[topic]
target = total - initialpos
delta = pos - initialpos
if delta > 0:
elapsed = now - self.starttimes[topic]
seconds = (elapsed * (target - delta)) // delta + 1
return fmtremaining(seconds)
return ''
def speed(self, topic, pos, unit, now):
initialpos = self.startvals[topic]
delta = pos - initialpos
elapsed = now - self.starttimes[topic]
if elapsed > 0:
return _('%d %s/sec') % (delta / elapsed, unit)
return ''
def _oktoprint(self, now):
'''Check if conditions are met to print - e.g. changedelay elapsed'''
if (self.lasttopic is None # first time we printed
# not a topic change
or self.curtopic == self.lasttopic
# it's been long enough we should print anyway
or now - self.lastprint >= self.changedelay):
return True
else:
return False
def _calibrateestimate(self, topic, now, pos):
'''Adjust starttimes and startvals for topic so ETA works better
If progress is non-linear (ex. get much slower in the last minute),
it's more friendly to only use a recent time span for ETA and speed
calculation.
[======================================> ]
^^^^^^^
estimateinterval, only use this for estimation
'''
interval = self.estimateinterval
if interval <= 0:
return
elapsed = now - self.starttimes[topic]
if elapsed > interval:
delta = pos - self.startvals[topic]
newdelta = delta * interval / elapsed
# If a stall happens temporarily, ETA could change dramatically
# frequently. This is to avoid such dramatical change and make ETA
# smoother.
if newdelta < 0.1:
return
self.startvals[topic] = pos - newdelta
self.starttimes[topic] = now - interval
def progress(self, topic, pos, item='', unit='', total=None):
now = time.time()
self._refreshlock.acquire()
try:
if pos is None:
self.starttimes.pop(topic, None)
self.startvals.pop(topic, None)
self.topicstates.pop(topic, None)
# reset the progress bar if this is the outermost topic
if self.topics and self.topics[0] == topic and self.printed:
self.complete()
self.resetstate()
# truncate the list of topics assuming all topics within
# this one are also closed
if topic in self.topics:
self.topics = self.topics[:self.topics.index(topic)]
# reset the last topic to the one we just unwound to,
# so that higher-level topics will be stickier than
# lower-level topics
if self.topics:
self.lasttopic = self.topics[-1]
else:
self.lasttopic = None
else:
if topic not in self.topics:
self.starttimes[topic] = now
self.startvals[topic] = pos
self.topics.append(topic)
self.topicstates[topic] = pos, item, unit, total
self.curtopic = topic
self._calibrateestimate(topic, now, pos)
if now - self.lastprint >= self.refresh and self.topics:
if self._oktoprint(now):
self.lastprint = now
self.show(now, topic, *self.topicstates[topic])
finally:
self._refreshlock.release()