"""Default variable filters."""
from __future__ import unicode_literals
import re
import random as random_module
from decimal import Decimal, InvalidOperation, Context, ROUND_HALF_UP
from functools import wraps
from pprint import pformat
from django.template.base import Variable, Library, VariableDoesNotExist
from django.conf import settings
from django.utils import formats
from django.utils.dateformat import format, time_format
from django.utils.encoding import force_text, iri_to_uri
from django.utils.html import (conditional_escape, escapejs, fix_ampersands,
escape, urlize as urlize_impl, linebreaks, strip_tags, avoid_wrapping)
from django.utils.http import urlquote
from django.utils.text import Truncator, wrap, phone2numeric
from django.utils.safestring import mark_safe, SafeData, mark_for_escaping
from django.utils import six
from django.utils.timesince import timesince, timeuntil
from django.utils.translation import ugettext, ungettext
from django.utils.text import normalize_newlines
register = Library()
#######################
# STRING DECORATOR #
#######################
def stringfilter(func):
"""
Decorator for filters which should only receive unicode objects. The object
passed as the first positional argument will be converted to a unicode
object.
"""
def _dec(*args, **kwargs):
if args:
args = list(args)
args[0] = force_text(args[0])
if (isinstance(args[0], SafeData) and
getattr(_dec._decorated_function, 'is_safe', False)):
return mark_safe(func(*args, **kwargs))
return func(*args, **kwargs)
# Include a reference to the real function (used to check original
# arguments by the template parser, and to bear the 'is_safe' attribute
# when multiple decorators are applied).
_dec._decorated_function = getattr(func, '_decorated_function', func)
return wraps(func)(_dec)
###################
# STRINGS #
###################
@register.filter(is_safe=True)
@stringfilter
def addslashes(value):
"""
Adds slashes before quotes. Useful for escaping strings in CSV, for
example. Less useful for escaping JavaScript; use the ``escapejs``
filter instead.
"""
return value.replace('\\', '\\\\').replace('"', '\\"').replace("'", "\\'")
@register.filter(is_safe=True)
@stringfilter
def capfirst(value):
"""Capitalizes the first character of the value."""
return value and value[0].upper() + value[1:]
@register.filter("escapejs")
@stringfilter
def escapejs_filter(value):
"""Hex encodes characters for use in JavaScript strings."""
return escapejs(value)
@register.filter("fix_ampersands", is_safe=True)
@stringfilter
def fix_ampersands_filter(value):
"""Replaces ampersands with ``&`` entities."""
return fix_ampersands(value)
# Values for testing floatformat input against infinity and NaN representations,
# which differ across platforms and Python versions. Some (i.e. old Windows
# ones) are not recognized by Decimal but we want to return them unchanged vs.
# returning an empty string as we do for completely invalid input. Note these
# need to be built up from values that are not inf/nan, since inf/nan values do
# not reload properly from .pyc files on Windows prior to some level of Python 2.5
# (see Python Issue757815 and Issue1080440).
pos_inf = 1e200 * 1e200
neg_inf = -1e200 * 1e200
nan = (1e200 * 1e200) // (1e200 * 1e200)
special_floats = [str(pos_inf), str(neg_inf), str(nan)]
@register.filter(is_safe=True)
def floatformat(text, arg=-1):
"""
Displays a float to a specified number of decimal places.
If called without an argument, it displays the floating point number with
one decimal place -- but only if there's a decimal place to be displayed:
* num1 = 34.23234
* num2 = 34.00000
* num3 = 34.26000
* {{ num1|floatformat }} displays "34.2"
* {{ num2|floatformat }} displays "34"
* {{ num3|floatformat }} displays "34.3"
If arg is positive, it will always display exactly arg number of decimal
places:
* {{ num1|floatformat:3 }} displays "34.232"
* {{ num2|floatformat:3 }} displays "34.000"
* {{ num3|floatformat:3 }} displays "34.260"
If arg is negative, it will display arg number of decimal places -- but
only if there are places to be displayed:
* {{ num1|floatformat:"-3" }} displays "34.232"
* {{ num2|floatformat:"-3" }} displays "34"
* {{ num3|floatformat:"-3" }} displays "34.260"
If the input float is infinity or NaN, the (platform-dependent) string
representation of that value will be displayed.
"""
try:
input_val = force_text(text)
d = Decimal(input_val)
except UnicodeEncodeError:
return ''
except InvalidOperation:
if input_val in special_floats:
return input_val
try:
d = Decimal(force_text(float(text)))
except (ValueError, InvalidOperation, TypeError, UnicodeEncodeError):
return ''
try:
p = int(arg)
except ValueError:
return input_val
try:
m = int(d) - d
except (ValueError, OverflowError, InvalidOperation):
return input_val
if not m and p < 0:
return mark_safe(formats.number_format('%d' % (int(d)), 0))
if p == 0:
exp = Decimal(1)
else:
exp = Decimal('1.0') / (Decimal(10) ** abs(p))
try:
# Set the precision high enough to avoid an exception, see #15789.
tupl = d.as_tuple()
units = len(tupl[1]) - tupl[2]
prec = abs(p) + units + 1
# Avoid conversion to scientific notation by accessing `sign`, `digits`
# and `exponent` from `Decimal.as_tuple()` directly.
sign, digits, exponent = d.quantize(exp, ROUND_HALF_UP,
Context(prec=prec)).as_tuple()
digits = [six.text_type(digit) for digit in reversed(digits)]
while len(digits) <= abs(exponent):
digits.append('0')
digits.insert(-exponent, '.')
if sign:
digits.append('-')
number = ''.join(reversed(digits))
return mark_safe(formats.number_format(number, abs(p)))
except InvalidOperation:
return input_val
@register.filter(is_safe=True)
@stringfilter
def iriencode(value):
"""Escapes an IRI value for use in a URL."""
return force_text(iri_to_uri(value))
@register.filter(is_safe=True, needs_autoescape=True)
@stringfilter
def linenumbers(value, autoescape=None):
"""Displays text with line numbers."""
lines = value.split('\n')
# Find the maximum width of the line count, for use with zero padding
# string format command
width = six.text_type(len(six.text_type(len(lines))))
if not autoescape or isinstance(value, SafeData):
for i, line in enumerate(lines):
lines[i] = ("%0" + width + "d. %s") % (i + 1, line)
else:
for i, line in enumerate(lines):
lines[i] = ("%0" + width + "d. %s") % (i + 1, escape(line))
return mark_safe('\n'.join(lines))
@register.filter(is_safe=True)
@stringfilter
def lower(value):
"""Converts a string into all lowercase."""
return value.lower()
@register.filter(is_safe=False)
@stringfilter
def make_list(value):
"""
Returns the value turned into a list.
For an integer, it's a list of digits.
For a string, it's a list of characters.
"""
return list(value)
@register.filter(is_safe=True)
@stringfilter
def slugify(value):
"""
Converts to lowercase, removes non-word characters (alphanumerics and
underscores) and converts spaces to hyphens. Also strips leading and
trailing whitespace.
"""
from django.utils.text import slugify
return slugify(value)
@register.filter(is_safe=True)
def stringformat(value, arg):
"""
Formats the variable according to the arg, a string formatting specifier.
This specifier uses Python string formating syntax, with the exception that
the leading "%" is dropped.
See http://docs.python.org/lib/typesseq-strings.html for documentation
of Python string formatting
"""
try:
return ("%" + six.text_type(arg)) % value
except (ValueError, TypeError):
return ""
@register.filter(is_safe=True)
@stringfilter
def title(value):
"""Converts a string into titlecase."""
t = re.sub("([a-z])'([A-Z])", lambda m: m.group(0).lower(), value.title())
return re.sub("\d([A-Z])", lambda m: m.group(0).lower(), t)
@register.filter(is_safe=True)
@stringfilter
def truncatechars(value, arg):
"""
Truncates a string after a certain number of characters.
Argument: Number of characters to truncate after.
"""
try:
length = int(arg)
except ValueError: # Invalid literal for int().
return value # Fail silently.
return Truncator(value).chars(length)
@register.filter(is_safe=True)
@stringfilter
def truncatewords(value, arg):
"""
Truncates a string after a certain number of words.
Argument: Number of words to truncate after.
Newlines within the string are removed.
"""
try:
length = int(arg)
except ValueError: # Invalid literal for int().
return value # Fail silently.
return Truncator(value).words(length, truncate=' ...')
@register.filter(is_safe=True)
@stringfilter
def truncatewords_html(value, arg):
"""
Truncates HTML after a certain number of words.
Argument: Number of words to truncate after.
Newlines in the HTML are preserved.
"""
try:
length = int(arg)
except ValueError: # invalid literal for int()
return value # Fail silently.
return Truncator(value).words(length, html=True, truncate=' ...')
@register.filter(is_safe=False)
@stringfilter
def upper(value):
"""Converts a string into all uppercase."""
return value.upper()
@register.filter(is_safe=False)
@stringfilter
def urlencode(value, safe=None):
"""
Escapes a value for use in a URL.
Takes an optional ``safe`` parameter used to determine the characters which
should not be escaped by Django's ``urlquote`` method. If not provided, the
default safe characters will be used (but an empty string can be provided
when *all* characters should be escaped).
"""
kwargs = {}
if safe is not None:
kwargs['safe'] = safe
return urlquote(value, **kwargs)
@register.filter(is_safe=True, needs_autoescape=True)
@stringfilter
def urlize(value, autoescape=None):
"""Converts URLs in plain text into clickable links."""
return mark_safe(urlize_impl(value, nofollow=True, autoescape=autoescape))
@register.filter(is_safe=True, needs_autoescape=True)
@stringfilter
def urlizetrunc(value, limit, autoescape=None):
"""
Converts URLs into clickable links, truncating URLs to the given character
limit, and adding 'rel=nofollow' attribute to discourage spamming.
Argument: Length to truncate URLs to.
"""
return mark_safe(urlize_impl(value, trim_url_limit=int(limit), nofollow=True,
autoescape=autoescape))
@register.filter(is_safe=False)
@stringfilter
def wordcount(value):
"""Returns the number of words."""
return len(value.split())
@register.filter(is_safe=True)
@stringfilter
def wordwrap(value, arg):
"""
Wraps words at specified line length.
Argument: number of characters to wrap the text at.
"""
return wrap(value, int(arg))
@register.filter(is_safe=True)
@stringfilter
def ljust(value, arg):
"""
Left-aligns the value in a field of a given width.
Argument: field size.
"""
return value.ljust(int(arg))
@register.filter(is_safe=True)
@stringfilter
def rjust(value, arg):
"""
Right-aligns the value in a field of a given width.
Argument: field size.
"""
return value.rjust(int(arg))
@register.filter(is_safe=True)
@stringfilter
def center(value, arg):
"""Centers the value in a field of a given width."""
return value.center(int(arg))
@register.filter
@stringfilter
def cut(value, arg):
"""
Removes all values of arg from the given string.
"""
safe = isinstance(value, SafeData)
value = value.replace(arg, '')
if safe and arg != ';':
return mark_safe(value)
return value
###################
# HTML STRINGS #
###################
@register.filter("escape", is_safe=True)
@stringfilter
def escape_filter(value):
"""
Marks the value as a string that should not be auto-escaped.
"""
return mark_for_escaping(value)
@register.filter(is_safe=True)
@stringfilter
def force_escape(value):
"""
Escapes a string's HTML. This returns a new string containing the escaped
characters (as opposed to "escape", which marks the content for later
possible escaping).
"""
return escape(value)
@register.filter("linebreaks", is_safe=True, needs_autoescape=True)
@stringfilter
def linebreaks_filter(value, autoescape=None):
"""
Replaces line breaks in plain text with appropriate HTML; a single
newline becomes an HTML line break (``
``) and a new line
followed by a blank line becomes a paragraph break (``