Anki/anki/utils.py
Damien Elmes f32787c18e add guid and flags to facts
Syncing and shared decks have conflicting priorities:

- For syncing, we need to ensure that the deck remains in a consistent state.
  In the past, Anki allowed deletions to be overriden by a more recently
  modified object, but this could lead to a broken deck in certain
  circumstances. For example, if a user deletes a fact (and its cards) on one
  side, but does something to bump a card's mod time on another side, then
  when syncing the card would be brought back to life without its fact. Short
  of complex code to check all the relations, we're limited to two options:
  forcing a full sync when things are deleted, or ensuring objects can't come
  back to life.

- When facts are shared between people, we need a way to identify if two facts
  arose from the same source. We can't compare based on content, as the
  content may have changed partially or completely. And we can't use the
  timestamp ids because of the above restriction on bringing objects back to
  life. If we did that, people could download a shared deck, decide they don't
  want it, and delete it. When they later decide to add it again, it wouldn't
  be possible: either nothing would be imported because of the old graves, or
  the ids would have to be rewritten. If we do the latter, the facts are no
  longer associated with each other, and we lose the ability to update the
  deck.

So we need to give facts two IDs: one used as the primary key and for syncing,
and another 'global id' for importing/sharing. I used a 64 bit random number,
because a) it's what Anki's used in the past, so by reusing the old IDs we
don't break existing associations on upgrade, and b) it's a decent compromise
between the possibility of conflicts and performance.

Also re-added a flags column to the facts. The 'data' column is intended to
store JSON in the future for extra features without changing the schema, but
that's slow for simple state checks. Flags will be used as a bitmask.
2011-09-18 04:31:53 +09:00

280 lines
8.3 KiB
Python

# -*- coding: utf-8 -*-
# Copyright: Damien Elmes <anki@ichi2.net>
# License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
import re, os, random, time, types, math, htmlentitydefs, subprocess, \
tempfile, shutil
from hashlib import md5, sha1
from anki.lang import _, ngettext
import locale, sys
if sys.version_info[1] < 5:
def format_string(a, b):
return a % b
locale.format_string = format_string
# Time handling
##############################################################################
def intTime(scale=1):
"The time in integer seconds. Pass scale=1000 to get milliseconds."
return int(time.time()*scale)
timeTable = {
"years": lambda n: ngettext("%s year", "%s years", n),
"months": lambda n: ngettext("%s month", "%s months", n),
"days": lambda n: ngettext("%s day", "%s days", n),
"hours": lambda n: ngettext("%s hour", "%s hours", n),
"minutes": lambda n: ngettext("%s minute", "%s minutes", n),
"seconds": lambda n: ngettext("%s second", "%s seconds", n),
}
afterTimeTable = {
"years": lambda n: ngettext("%s year<!--after-->", "%s years<!--after-->", n),
"months": lambda n: ngettext("%s month<!--after-->", "%s months<!--after-->", n),
"days": lambda n: ngettext("%s day<!--after-->", "%s days<!--after-->", n),
"hours": lambda n: ngettext("%s hour<!--after-->", "%s hours<!--after-->", n),
"minutes": lambda n: ngettext("%s minute<!--after-->", "%s minutes<!--after-->", n),
"seconds": lambda n: ngettext("%s second<!--after-->", "%s seconds<!--after-->", n),
}
shortTimeTable = {
"years": _("%sy"),
"months": _("%smo"),
"days": _("%sd"),
"hours": _("%sh"),
"minutes": _("%sm"),
"seconds": _("%ss"),
}
def fmtTimeSpan(time, pad=0, point=0, short=False, after=False, unit=99):
"Return a string representing a time span (eg '2 days')."
(type, point) = optimalPeriod(time, point, unit)
time = convertSecondsTo(time, type)
if not point:
time = math.floor(time)
if short:
fmt = shortTimeTable[type]
else:
if after:
fmt = afterTimeTable[type](_pluralCount(time, point))
else:
fmt = timeTable[type](_pluralCount(time, point))
timestr = "%(a)d.%(b)df" % {'a': pad, 'b': point}
return locale.format_string("%" + (fmt % timestr), time)
def optimalPeriod(time, point, unit):
if abs(time) < 60 or unit < 1:
type = "seconds"
point -= 1
elif abs(time) < 3599 or unit < 2:
type = "minutes"
elif abs(time) < 60 * 60 * 24 or unit < 3:
type = "hours"
elif abs(time) < 60 * 60 * 24 * 30 or unit < 4:
type = "days"
elif abs(time) < 60 * 60 * 24 * 365 or unit < 5:
type = "months"
point += 1
else:
type = "years"
point += 1
return (type, max(point, 0))
def convertSecondsTo(seconds, type):
if type == "seconds":
return seconds
elif type == "minutes":
return seconds / 60.0
elif type == "hours":
return seconds / 3600.0
elif type == "days":
return seconds / 86400.0
elif type == "months":
return seconds / 2592000.0
elif type == "years":
return seconds / 31536000.0
assert False
def _pluralCount(time, point):
if point:
return 2
return math.floor(time)
# Locale
##############################################################################
def fmtPercentage(float_value, point=1):
"Return float with percentage sign"
fmt = '%' + "0.%(b)df" % {'b': point}
return locale.format_string(fmt, float_value) + "%"
def fmtFloat(float_value, point=1):
"Return a string with decimal separator according to current locale"
fmt = '%' + "0.%(b)df" % {'b': point}
return locale.format_string(fmt, float_value)
# HTML
##############################################################################
def stripHTML(s):
s = re.sub("(?s)<style.*?>.*?</style>", "", s)
s = re.sub("(?s)<script.*?>.*?</script>", "", s)
s = re.sub("<.*?>", "", s)
s = entsToTxt(s)
return s
def stripHTMLMedia(s):
"Strip HTML but keep media filenames"
s = re.sub("<img src=[\"']?([^\"'>]+)[\"']? ?/?>", " \\1 ", s)
return stripHTML(s)
def minimizeHTML(s):
"Correct Qt's verbose bold/underline/etc."
s = re.sub('<span style="font-weight:600;">(.*?)</span>', '<b>\\1</b>',
s)
s = re.sub('<span style="font-style:italic;">(.*?)</span>', '<i>\\1</i>',
s)
s = re.sub('<span style="text-decoration: underline;">(.*?)</span>',
'<u>\\1</u>', s)
return s
def entsToTxt(html):
def fixup(m):
text = m.group(0)
if text[:2] == "&#":
# character reference
try:
if text[:3] == "&#x":
return unichr(int(text[3:-1], 16))
else:
return unichr(int(text[2:-1]))
except ValueError:
pass
else:
# named entity
try:
text = unichr(htmlentitydefs.name2codepoint[text[1:-1]])
except KeyError:
pass
return text # leave as is
return re.sub("&#?\w+;", fixup, html)
# IDs
##############################################################################
def hexifyID(id):
return "%x" % int(id)
def dehexifyID(id):
return int(id, 16)
def ids2str(ids):
"""Given a list of integers, return a string '(int1,int2,...)'."""
return "(%s)" % ",".join(str(i) for i in ids)
def timestampID(db, table):
"Return a non-conflicting timestamp for table."
# be careful not to create multiple objects without flushing them, or they
# may share an ID.
t = intTime(1000)
while db.scalar("select id from %s where id = ?" % table, t):
t += 1
return t
def guid64():
return random.randint(-sys.maxint-1, sys.maxint)
# Fields
##############################################################################
def joinFields(list):
return "\x1f".join(list)
def splitFields(string):
return string.split("\x1f")
# Checksums
##############################################################################
def checksum(data):
return md5(data).hexdigest()
def sha1sum(data):
return sha1(data).hexdigest()
def fieldChecksum(data):
# 32 bit unsigned number from first 8 digits of md5 hash
return int(checksum(data.encode("utf-8"))[:8], 16)
# Temp files
##############################################################################
_tmpdir = None
def tmpdir():
"A reusable temp folder which we clean out on each program invocation."
global _tmpdir
if not _tmpdir:
def cleanup():
shutil.rmtree(_tmpdir)
import atexit
atexit.register(cleanup)
_tmpdir = os.path.join(tempfile.gettempdir(), "anki_temp")
try:
shutil.rmtree(_tmpdir)
except (IOError, OSError):
pass
os.mkdir(_tmpdir)
return _tmpdir
def tmpfile(prefix=None, suffix=None):
return tempfile.mkstemp(dir=tmpdir(), prefix=prefix, suffix=suffix)
def namedtmp(name):
"Return tmpdir+name. Deletes any existing file."
path = os.path.join(tmpdir(), name)
try:
os.unlink(path)
except (OSError, IOError):
pass
return path
# Cmd invocation
##############################################################################
def call(argv, wait=True, **kwargs):
"Execute a command. If WAIT, return exit code."
# ensure we don't open a separate window for forking process on windows
if isWin:
si = subprocess.STARTUPINFO()
try:
si.dwFlags |= subprocess.STARTF_USESHOWWINDOW
except:
si.dwFlags |= subprocess._subprocess.STARTF_USESHOWWINDOW
else:
si = None
# run
try:
o = subprocess.Popen(argv, startupinfo=si, **kwargs)
except OSError:
# command not found
return -1
# wait for command to finish
if wait:
while 1:
try:
ret = o.wait()
except OSError:
# interrupted system call
continue
break
else:
ret = 0
return ret
# OS helpers
##############################################################################
isMac = sys.platform.startswith("darwin")
isWin = sys.platform.startswith("win32")