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# -*- coding: utf-8 -*-
"""
jinja2.filters
~~~~~~~~~~~~~~
Bundled jinja filters.
:copyright: (c) 2017 by the Jinja Team.
:license: BSD, see LICENSE for more details.
"""
import re
import math
import random
import warnings
from itertools import groupby, chain
from collections import namedtuple
from jinja2.utils import Markup, escape, pformat, urlize, soft_unicode, \
unicode_urlencode, htmlsafe_json_dumps
from jinja2.runtime import Undefined
from jinja2.exceptions import FilterArgumentError
from jinja2._compat import imap, string_types, text_type, iteritems, PY2
_word_re = re.compile(r'\w+', re.UNICODE)
_word_beginning_split_re = re.compile(r'([-\s\(\{\[\<]+)', re.UNICODE)
def contextfilter(f):
"""Decorator for marking context dependent filters. The current
:class:`Context` will be passed as first argument.
"""
f.contextfilter = True
return f
def evalcontextfilter(f):
"""Decorator for marking eval-context dependent filters. An eval
context object is passed as first argument. For more information
about the eval context, see :ref:`eval-context`.
.. versionadded:: 2.4
"""
f.evalcontextfilter = True
return f
def environmentfilter(f):
"""Decorator for marking environment dependent filters. The current
:class:`Environment` is passed to the filter as first argument.
"""
f.environmentfilter = True
return f
def ignore_case(value):
"""For use as a postprocessor for :func:`make_attrgetter`. Converts strings
to lowercase and returns other types as-is."""
return value.lower() if isinstance(value, string_types) else value
def make_attrgetter(environment, attribute, postprocess=None):
"""Returns a callable that looks up the given attribute from a
passed object with the rules of the environment. Dots are allowed
to access attributes of attributes. Integer parts in paths are
looked up as integers.
"""
if attribute is None:
attribute = []
elif isinstance(attribute, string_types):
attribute = [int(x) if x.isdigit() else x for x in attribute.split('.')]
else:
attribute = [attribute]
def attrgetter(item):
for part in attribute:
item = environment.getitem(item, part)
if postprocess is not None:
item = postprocess(item)
return item
return attrgetter
def do_forceescape(value):
"""Enforce HTML escaping. This will probably double escape variables."""
if hasattr(value, '__html__'):
value = value.__html__()
return escape(text_type(value))
def do_urlencode(value):
"""Escape strings for use in URLs (uses UTF-8 encoding). It accepts both
dictionaries and regular strings as well as pairwise iterables.
.. versionadded:: 2.7
"""
itemiter = None
if isinstance(value, dict):
itemiter = iteritems(value)
elif not isinstance(value, string_types):
try:
itemiter = iter(value)
except TypeError:
pass
if itemiter is None:
return unicode_urlencode(value)
return u'&'.join(unicode_urlencode(k) + '=' +
unicode_urlencode(v, for_qs=True)
for k, v in itemiter)
@evalcontextfilter
def do_replace(eval_ctx, s, old, new, count=None):
"""Return a copy of the value with all occurrences of a substring
replaced with a new one. The first argument is the substring
that should be replaced, the second is the replacement string.
If the optional third argument ``count`` is given, only the first
``count`` occurrences are replaced:
.. sourcecode:: jinja
{{ "Hello World"|replace("Hello", "Goodbye") }}
-> Goodbye World
{{ "aaaaargh"|replace("a", "d'oh, ", 2) }}
-> d'oh, d'oh, aaargh
"""
if count is None:
count = -1
if not eval_ctx.autoescape:
return text_type(s).replace(text_type(old), text_type(new), count)
if hasattr(old, '__html__') or hasattr(new, '__html__') and \
not hasattr(s, '__html__'):
s = escape(s)
else:
s = soft_unicode(s)
return s.replace(soft_unicode(old), soft_unicode(new), count)
def do_upper(s):
"""Convert a value to uppercase."""
return soft_unicode(s).upper()
def do_lower(s):
"""Convert a value to lowercase."""
return soft_unicode(s).lower()
@evalcontextfilter
def do_xmlattr(_eval_ctx, d, autospace=True):
"""Create an SGML/XML attribute string based on the items in a dict.
All values that are neither `none` nor `undefined` are automatically
escaped:
.. sourcecode:: html+jinja
<ul{{ {'class': 'my_list', 'missing': none,
'id': 'list-%d'|format(variable)}|xmlattr }}>
...
</ul>
Results in something like this:
.. sourcecode:: html
<ul class="my_list" id="list-42">
...
</ul>
As you can see it automatically prepends a space in front of the item
if the filter returned something unless the second parameter is false.
"""
rv = u' '.join(
u'%s="%s"' % (escape(key), escape(value))
for key, value in iteritems(d)
if value is not None and not isinstance(value, Undefined)
)
if autospace and rv:
rv = u' ' + rv
if _eval_ctx.autoescape:
rv = Markup(rv)
return rv
def do_capitalize(s):
"""Capitalize a value. The first character will be uppercase, all others
lowercase.
"""
return soft_unicode(s).capitalize()
def do_title(s):
"""Return a titlecased version of the value. I.e. words will start with
uppercase letters, all remaining characters are lowercase.
"""
return ''.join(
[item[0].upper() + item[1:].lower()
for item in _word_beginning_split_re.split(soft_unicode(s))
if item])
def do_dictsort(value, case_sensitive=False, by='key', reverse=False):
"""Sort a dict and yield (key, value) pairs. Because python dicts are
unsorted you may want to use this function to order them by either
key or value:
.. sourcecode:: jinja
{% for item in mydict|dictsort %}
sort the dict by key, case insensitive
{% for item in mydict|dictsort(reverse=true) %}
sort the dict by key, case insensitive, reverse order
{% for item in mydict|dictsort(true) %}
sort the dict by key, case sensitive
{% for item in mydict|dictsort(false, 'value') %}
sort the dict by value, case insensitive
"""
if by == 'key':
pos = 0
elif by == 'value':
pos = 1
else:
raise FilterArgumentError(
'You can only sort by either "key" or "value"'
)
def sort_func(item):
value = item[pos]
if not case_sensitive:
value = ignore_case(value)
return value
return sorted(value.items(), key=sort_func, reverse=reverse)
@environmentfilter
def do_sort(
environment, value, reverse=False, case_sensitive=False, attribute=None
):
"""Sort an iterable. Per default it sorts ascending, if you pass it
true as first argument it will reverse the sorting.
If the iterable is made of strings the third parameter can be used to
control the case sensitiveness of the comparison which is disabled by
default.
.. sourcecode:: jinja
{% for item in iterable|sort %}
...
{% endfor %}
It is also possible to sort by an attribute (for example to sort
by the date of an object) by specifying the `attribute` parameter:
.. sourcecode:: jinja
{% for item in iterable|sort(attribute='date') %}
...
{% endfor %}
.. versionchanged:: 2.6
The `attribute` parameter was added.
"""
key_func = make_attrgetter(
environment, attribute,
postprocess=ignore_case if not case_sensitive else None
)
return sorted(value, key=key_func, reverse=reverse)
@environmentfilter
def do_unique(environment, value, case_sensitive=False, attribute=None):
"""Returns a list of unique items from the the given iterable.
.. sourcecode:: jinja
{{ ['foo', 'bar', 'foobar', 'FooBar']|unique }}
-> ['foo', 'bar', 'foobar']
The unique items are yielded in the same order as their first occurrence in
the iterable passed to the filter.
:param case_sensitive: Treat upper and lower case strings as distinct.
:param attribute: Filter objects with unique values for this attribute.
"""
getter = make_attrgetter(
environment, attribute,
postprocess=ignore_case if not case_sensitive else None
)
seen = set()
for item in value:
key = getter(item)
if key not in seen:
seen.add(key)
yield item
def _min_or_max(environment, value, func, case_sensitive, attribute):
it = iter(value)
try:
first = next(it)
except StopIteration:
return environment.undefined('No aggregated item, sequence was empty.')
key_func = make_attrgetter(
environment, attribute,
ignore_case if not case_sensitive else None
)
return func(chain([first], it), key=key_func)
@environmentfilter
def do_min(environment, value, case_sensitive=False, attribute=None):
"""Return the smallest item from the sequence.
.. sourcecode:: jinja
{{ [1, 2, 3]|min }}
-> 1
:param case_sensitive: Treat upper and lower case strings as distinct.
:param attribute: Get the object with the max value of this attribute.
"""
return _min_or_max(environment, value, min, case_sensitive, attribute)
@environmentfilter
def do_max(environment, value, case_sensitive=False, attribute=None):
"""Return the smallest item from the sequence.
.. sourcecode:: jinja
{{ [1, 2, 3]|max }}
-> 3
:param case_sensitive: Treat upper and lower case strings as distinct.
:param attribute: Get the object with the max value of this attribute.
"""
return _min_or_max(environment, value, max, case_sensitive, attribute)
def do_default(value, default_value=u'', boolean=False):
"""If the value is undefined it will return the passed default value,
otherwise the value of the variable:
.. sourcecode:: jinja
{{ my_variable|default('my_variable is not defined') }}
This will output the value of ``my_variable`` if the variable was
defined, otherwise ``'my_variable is not defined'``. If you want
to use default with variables that evaluate to false you have to
set the second parameter to `true`:
.. sourcecode:: jinja
{{ ''|default('the string was empty', true) }}
"""
if isinstance(value, Undefined) or (boolean and not value):
return default_value
return value
@evalcontextfilter
def do_join(eval_ctx, value, d=u'', attribute=None):
"""Return a string which is the concatenation of the strings in the
sequence. The separator between elements is an empty string per
default, you can define it with the optional parameter:
.. sourcecode:: jinja
{{ [1, 2, 3]|join('|') }}
-> 1|2|3
{{ [1, 2, 3]|join }}
-> 123
It is also possible to join certain attributes of an object:
.. sourcecode:: jinja
{{ users|join(', ', attribute='username') }}
.. versionadded:: 2.6
The `attribute` parameter was added.
"""
if attribute is not None:
value = imap(make_attrgetter(eval_ctx.environment, attribute), value)
# no automatic escaping? joining is a lot eaiser then
if not eval_ctx.autoescape:
return text_type(d).join(imap(text_type, value))
# if the delimiter doesn't have an html representation we check
# if any of the items has. If yes we do a coercion to Markup
if not hasattr(d, '__html__'):
value = list(value)
do_escape = False
for idx, item in enumerate(value):
if hasattr(item, '__html__'):
do_escape = True
else:
value[idx] = text_type(item)
if do_escape:
d = escape(d)
else:
d = text_type(d)
return d.join(value)
# no html involved, to normal joining
return soft_unicode(d).join(imap(soft_unicode, value))
def do_center(value, width=80):
"""Centers the value in a field of a given width."""
return text_type(value).center(width)
@environmentfilter
def do_first(environment, seq):
"""Return the first item of a sequence."""
try:
return next(iter(seq))
except StopIteration:
return environment.undefined('No first item, sequence was empty.')
@environmentfilter
def do_last(environment, seq):
"""Return the last item of a sequence."""
try:
return next(iter(reversed(seq)))
except StopIteration:
return environment.undefined('No last item, sequence was empty.')
@contextfilter
def do_random(context, seq):
"""Return a random item from the sequence."""
try:
return random.choice(seq)
except IndexError:
return context.environment.undefined('No random item, sequence was empty.')
def do_filesizeformat(value, binary=False):
"""Format the value like a 'human-readable' file size (i.e. 13 kB,
4.1 MB, 102 Bytes, etc). Per default decimal prefixes are used (Mega,
Giga, etc.), if the second parameter is set to `True` the binary
prefixes are used (Mebi, Gibi).
"""
bytes = float(value)
base = binary and 1024 or 1000
prefixes = [
(binary and 'KiB' or 'kB'),
(binary and 'MiB' or 'MB'),
(binary and 'GiB' or 'GB'),
(binary and 'TiB' or 'TB'),
(binary and 'PiB' or 'PB'),
(binary and 'EiB' or 'EB'),
(binary and 'ZiB' or 'ZB'),
(binary and 'YiB' or 'YB')
]
if bytes == 1:
return '1 Byte'
elif bytes < base:
return '%d Bytes' % bytes
else:
for i, prefix in enumerate(prefixes):
unit = base ** (i + 2)
if bytes < unit:
return '%.1f %s' % ((base * bytes / unit), prefix)
return '%.1f %s' % ((base * bytes / unit), prefix)
def do_pprint(value, verbose=False):
"""Pretty print a variable. Useful for debugging.
With Jinja 1.2 onwards you can pass it a parameter. If this parameter
is truthy the output will be more verbose (this requires `pretty`)
"""
return pformat(value, verbose=verbose)
@evalcontextfilter
def do_urlize(eval_ctx, value, trim_url_limit=None, nofollow=False,
target=None, rel=None):
"""Converts URLs in plain text into clickable links.
If you pass the filter an additional integer it will shorten the urls
to that number. Also a third argument exists that makes the urls
"nofollow":
.. sourcecode:: jinja
{{ mytext|urlize(40, true) }}
links are shortened to 40 chars and defined with rel="nofollow"
If *target* is specified, the ``target`` attribute will be added to the
``<a>`` tag:
.. sourcecode:: jinja
{{ mytext|urlize(40, target='_blank') }}
.. versionchanged:: 2.8+
The *target* parameter was added.
"""
policies = eval_ctx.environment.policies
rel = set((rel or '').split() or [])
if nofollow:
rel.add('nofollow')
rel.update((policies['urlize.rel'] or '').split())
if target is None:
target = policies['urlize.target']
rel = ' '.join(sorted(rel)) or None
rv = urlize(value, trim_url_limit, rel=rel, target=target)
if eval_ctx.autoescape:
rv = Markup(rv)
return rv
def do_indent(
s, width=4, first=False, blank=False, indentfirst=None
):
"""Return a copy of the string with each line indented by 4 spaces. The
first line and blank lines are not indented by default.
:param width: Number of spaces to indent by.
:param first: Don't skip indenting the first line.
:param blank: Don't skip indenting empty lines.
.. versionchanged:: 2.10
Blank lines are not indented by default.
Rename the ``indentfirst`` argument to ``first``.
"""
if indentfirst is not None:
warnings.warn(DeprecationWarning(
'The "indentfirst" argument is renamed to "first".'
), stacklevel=2)
first = indentfirst
s += u'\n' # this quirk is necessary for splitlines method
indention = u' ' * width
if blank:
rv = (u'\n' + indention).join(s.splitlines())
else:
lines = s.splitlines()
rv = lines.pop(0)
if lines:
rv += u'\n' + u'\n'.join(
indention + line if line else line for line in lines
)
if first:
rv = indention + rv
return rv
@environmentfilter
def do_truncate(env, s, length=255, killwords=False, end='...', leeway=None):
"""Return a truncated copy of the string. The length is specified
with the first parameter which defaults to ``255``. If the second
parameter is ``true`` the filter will cut the text at length. Otherwise
it will discard the last word. If the text was in fact
truncated it will append an ellipsis sign (``"..."``). If you want a
different ellipsis sign than ``"..."`` you can specify it using the
third parameter. Strings that only exceed the length by the tolerance
margin given in the fourth parameter will not be truncated.
.. sourcecode:: jinja
{{ "foo bar baz qux"|truncate(9) }}
-> "foo..."
{{ "foo bar baz qux"|truncate(9, True) }}
-> "foo ba..."
{{ "foo bar baz qux"|truncate(11) }}
-> "foo bar baz qux"
{{ "foo bar baz qux"|truncate(11, False, '...', 0) }}
-> "foo bar..."
The default leeway on newer Jinja2 versions is 5 and was 0 before but
can be reconfigured globally.
"""
if leeway is None:
leeway = env.policies['truncate.leeway']
assert length >= len(end), 'expected length >= %s, got %s' % (len(end), length)
assert leeway >= 0, 'expected leeway >= 0, got %s' % leeway
if len(s) <= length + leeway:
return s
if killwords:
return s[:length - len(end)] + end
result = s[:length - len(end)].rsplit(' ', 1)[0]
return result + end
@environmentfilter
def do_wordwrap(environment, s, width=79, break_long_words=True,
wrapstring=None):
"""
Return a copy of the string passed to the filter wrapped after
``79`` characters. You can override this default using the first
parameter. If you set the second parameter to `false` Jinja will not
split words apart if they are longer than `width`. By default, the newlines
will be the default newlines for the environment, but this can be changed
using the wrapstring keyword argument.
.. versionadded:: 2.7
Added support for the `wrapstring` parameter.
"""
if not wrapstring:
wrapstring = environment.newline_sequence
import textwrap
return wrapstring.join(textwrap.wrap(s, width=width, expand_tabs=False,
replace_whitespace=False,
break_long_words=break_long_words))
def do_wordcount(s):
"""Count the words in that string."""
return len(_word_re.findall(s))
def do_int(value, default=0, base=10):
"""Convert the value into an integer. If the
conversion doesn't work it will return ``0``. You can
override this default using the first parameter. You
can also override the default base (10) in the second
parameter, which handles input with prefixes such as
0b, 0o and 0x for bases 2, 8 and 16 respectively.
The base is ignored for decimal numbers and non-string values.
"""
try:
if isinstance(value, string_types):
return int(value, base)
return int(value)
except (TypeError, ValueError):
# this quirk is necessary so that "42.23"|int gives 42.
try:
return int(float(value))
except (TypeError, ValueError):
return default
def do_float(value, default=0.0):
"""Convert the value into a floating point number. If the
conversion doesn't work it will return ``0.0``. You can
override this default using the first parameter.
"""
try:
return float(value)
except (TypeError, ValueError):
return default
def do_format(value, *args, **kwargs):
"""
Apply python string formatting on an object:
.. sourcecode:: jinja
{{ "%s - %s"|format("Hello?", "Foo!") }}
-> Hello? - Foo!
"""
if args and kwargs:
raise FilterArgumentError('can\'t handle positional and keyword '
'arguments at the same time')
return soft_unicode(value) % (kwargs or args)
def do_trim(value):
"""Strip leading and trailing whitespace."""
return soft_unicode(value).strip()
def do_striptags(value):
"""Strip SGML/XML tags and replace adjacent whitespace by one space.
"""
if hasattr(value, '__html__'):
value = value.__html__()
return Markup(text_type(value)).striptags()
def do_slice(value, slices, fill_with=None):
"""Slice an iterator and return a list of lists containing
those items. Useful if you want to create a div containing
three ul tags that represent columns:
.. sourcecode:: html+jinja
<div class="columwrapper">
{%- for column in items|slice(3) %}
<ul class="column-{{ loop.index }}">
{%- for item in column %}
<li>{{ item }}</li>
{%- endfor %}
</ul>
{%- endfor %}
</div>
If you pass it a second argument it's used to fill missing
values on the last iteration.
"""
seq = list(value)
length = len(seq)
items_per_slice = length // slices
slices_with_extra = length % slices
offset = 0
for slice_number in range(slices):
start = offset + slice_number * items_per_slice
if slice_number < slices_with_extra:
offset += 1
end = offset + (slice_number + 1) * items_per_slice
tmp = seq[start:end]
if fill_with is not None and slice_number >= slices_with_extra:
tmp.append(fill_with)
yield tmp
def do_batch(value, linecount, fill_with=None):
"""
A filter that batches items. It works pretty much like `slice`
just the other way round. It returns a list of lists with the
given number of items. If you provide a second parameter this
is used to fill up missing items. See this example:
.. sourcecode:: html+jinja
<table>
{%- for row in items|batch(3, '&nbsp;') %}
<tr>
{%- for column in row %}
<td>{{ column }}</td>
{%- endfor %}
</tr>
{%- endfor %}
</table>
"""
tmp = []
for item in value:
if len(tmp) == linecount:
yield tmp
tmp = []
tmp.append(item)
if tmp:
if fill_with is not None and len(tmp) < linecount:
tmp += [fill_with] * (linecount - len(tmp))
yield tmp
def do_round(value, precision=0, method='common'):
"""Round the number to a given precision. The first
parameter specifies the precision (default is ``0``), the
second the rounding method:
- ``'common'`` rounds either up or down
- ``'ceil'`` always rounds up
- ``'floor'`` always rounds down
If you don't specify a method ``'common'`` is used.
.. sourcecode:: jinja
{{ 42.55|round }}
-> 43.0
{{ 42.55|round(1, 'floor') }}
-> 42.5
Note that even if rounded to 0 precision, a float is returned. If
you need a real integer, pipe it through `int`:
.. sourcecode:: jinja
{{ 42.55|round|int }}
-> 43
"""
if not method in ('common', 'ceil', 'floor'):
raise FilterArgumentError('method must be common, ceil or floor')
if method == 'common':
return round(value, precision)
func = getattr(math, method)
return func(value * (10 ** precision)) / (10 ** precision)
# Use a regular tuple repr here. This is what we did in the past and we
# really want to hide this custom type as much as possible. In particular
# we do not want to accidentally expose an auto generated repr in case
# people start to print this out in comments or something similar for
# debugging.
_GroupTuple = namedtuple('_GroupTuple', ['grouper', 'list'])
_GroupTuple.__repr__ = tuple.__repr__
_GroupTuple.__str__ = tuple.__str__
@environmentfilter
def do_groupby(environment, value, attribute):
"""Group a sequence of objects by a common attribute.
If you for example have a list of dicts or objects that represent persons
with `gender`, `first_name` and `last_name` attributes and you want to
group all users by genders you can do something like the following
snippet:
.. sourcecode:: html+jinja
<ul>
{% for group in persons|groupby('gender') %}
<li>{{ group.grouper }}<ul>
{% for person in group.list %}
<li>{{ person.first_name }} {{ person.last_name }}</li>
{% endfor %}</ul></li>
{% endfor %}
</ul>
Additionally it's possible to use tuple unpacking for the grouper and
list:
.. sourcecode:: html+jinja
<ul>
{% for grouper, list in persons|groupby('gender') %}
...
{% endfor %}
</ul>
As you can see the item we're grouping by is stored in the `grouper`
attribute and the `list` contains all the objects that have this grouper
in common.
.. versionchanged:: 2.6
It's now possible to use dotted notation to group by the child
attribute of another attribute.
"""
expr = make_attrgetter(environment, attribute)
return [_GroupTuple(key, list(values)) for key, values
in groupby(sorted(value, key=expr), expr)]
@environmentfilter
def do_sum(environment, iterable, attribute=None, start=0):
"""Returns the sum of a sequence of numbers plus the value of parameter
'start' (which defaults to 0). When the sequence is empty it returns
start.
It is also possible to sum up only certain attributes:
.. sourcecode:: jinja
Total: {{ items|sum(attribute='price') }}
.. versionchanged:: 2.6
The `attribute` parameter was added to allow suming up over
attributes. Also the `start` parameter was moved on to the right.
"""
if attribute is not None:
iterable = imap(make_attrgetter(environment, attribute), iterable)
return sum(iterable, start)
def do_list(value):
"""Convert the value into a list. If it was a string the returned list
will be a list of characters.
"""
return list(value)
def do_mark_safe(value):
"""Mark the value as safe which means that in an environment with automatic
escaping enabled this variable will not be escaped.
"""
return Markup(value)
def do_mark_unsafe(value):
"""Mark a value as unsafe. This is the reverse operation for :func:`safe`."""
return text_type(value)
def do_reverse(value):
"""Reverse the object or return an iterator that iterates over it the other
way round.
"""
if isinstance(value, string_types):
return value[::-1]
try:
return reversed(value)
except TypeError:
try:
rv = list(value)
rv.reverse()
return rv
except TypeError:
raise FilterArgumentError('argument must be iterable')
@environmentfilter
def do_attr(environment, obj, name):
"""Get an attribute of an object. ``foo|attr("bar")`` works like
``foo.bar`` just that always an attribute is returned and items are not
looked up.
See :ref:`Notes on subscriptions <notes-on-subscriptions>` for more details.
"""
try:
name = str(name)
except UnicodeError:
pass
else:
try:
value = getattr(obj, name)
except AttributeError:
pass
else:
if environment.sandboxed and not \
environment.is_safe_attribute(obj, name, value):
return environment.unsafe_undefined(obj, name)
return value
return environment.undefined(obj=obj, name=name)
@contextfilter
def do_map(*args, **kwargs):
"""Applies a filter on a sequence of objects or looks up an attribute.
This is useful when dealing with lists of objects but you are really
only interested in a certain value of it.
The basic usage is mapping on an attribute. Imagine you have a list
of users but you are only interested in a list of usernames:
.. sourcecode:: jinja
Users on this page: {{ users|map(attribute='username')|join(', ') }}
Alternatively you can let it invoke a filter by passing the name of the
filter and the arguments afterwards. A good example would be applying a
text conversion filter on a sequence:
.. sourcecode:: jinja
Users on this page: {{ titles|map('lower')|join(', ') }}
.. versionadded:: 2.7
"""
seq, func = prepare_map(args, kwargs)
if seq:
for item in seq:
yield func(item)
@contextfilter
def do_select(*args, **kwargs):
"""Filters a sequence of objects by applying a test to each object,
and only selecting the objects with the test succeeding.
If no test is specified, each object will be evaluated as a boolean.
Example usage:
.. sourcecode:: jinja
{{ numbers|select("odd") }}
{{ numbers|select("odd") }}
{{ numbers|select("divisibleby", 3) }}
{{ numbers|select("lessthan", 42) }}
{{ strings|select("equalto", "mystring") }}
.. versionadded:: 2.7
"""
return select_or_reject(args, kwargs, lambda x: x, False)
@contextfilter
def do_reject(*args, **kwargs):
"""Filters a sequence of objects by applying a test to each object,
and rejecting the objects with the test succeeding.
If no test is specified, each object will be evaluated as a boolean.
Example usage:
.. sourcecode:: jinja
{{ numbers|reject("odd") }}
.. versionadded:: 2.7
"""
return select_or_reject(args, kwargs, lambda x: not x, False)
@contextfilter
def do_selectattr(*args, **kwargs):
"""Filters a sequence of objects by applying a test to the specified
attribute of each object, and only selecting the objects with the
test succeeding.
If no test is specified, the attribute's value will be evaluated as
a boolean.
Example usage:
.. sourcecode:: jinja
{{ users|selectattr("is_active") }}
{{ users|selectattr("email", "none") }}
.. versionadded:: 2.7
"""
return select_or_reject(args, kwargs, lambda x: x, True)
@contextfilter
def do_rejectattr(*args, **kwargs):
"""Filters a sequence of objects by applying a test to the specified
attribute of each object, and rejecting the objects with the test
succeeding.
If no test is specified, the attribute's value will be evaluated as
a boolean.
.. sourcecode:: jinja
{{ users|rejectattr("is_active") }}
{{ users|rejectattr("email", "none") }}
.. versionadded:: 2.7
"""
return select_or_reject(args, kwargs, lambda x: not x, True)
@evalcontextfilter
def do_tojson(eval_ctx, value, indent=None):
"""Dumps a structure to JSON so that it's safe to use in ``<script>``
tags. It accepts the same arguments and returns a JSON string. Note that
this is available in templates through the ``|tojson`` filter which will
also mark the result as safe. Due to how this function escapes certain
characters this is safe even if used outside of ``<script>`` tags.
The following characters are escaped in strings:
- ``<``
- ``>``
- ``&``
- ``'``
This makes it safe to embed such strings in any place in HTML with the
notable exception of double quoted attributes. In that case single
quote your attributes or HTML escape it in addition.
The indent parameter can be used to enable pretty printing. Set it to
the number of spaces that the structures should be indented with.
Note that this filter is for use in HTML contexts only.
.. versionadded:: 2.9
"""
policies = eval_ctx.environment.policies
dumper = policies['json.dumps_function']
options = policies['json.dumps_kwargs']
if indent is not None:
options = dict(options)
options['indent'] = indent
return htmlsafe_json_dumps(value, dumper=dumper, **options)
def prepare_map(args, kwargs):
context = args[0]
seq = args[1]
if len(args) == 2 and 'attribute' in kwargs:
attribute = kwargs.pop('attribute')
if kwargs:
raise FilterArgumentError('Unexpected keyword argument %r' %
next(iter(kwargs)))
func = make_attrgetter(context.environment, attribute)
else:
try:
name = args[2]
args = args[3:]
except LookupError:
raise FilterArgumentError('map requires a filter argument')
func = lambda item: context.environment.call_filter(
name, item, args, kwargs, context=context)
return seq, func
def prepare_select_or_reject(args, kwargs, modfunc, lookup_attr):
context = args[0]
seq = args[1]
if lookup_attr:
try:
attr = args[2]
except LookupError:
raise FilterArgumentError('Missing parameter for attribute name')
transfunc = make_attrgetter(context.environment, attr)
off = 1
else:
off = 0
transfunc = lambda x: x
try:
name = args[2 + off]
args = args[3 + off:]
func = lambda item: context.environment.call_test(
name, item, args, kwargs)
except LookupError:
func = bool
return seq, lambda item: modfunc(func(transfunc(item)))
def select_or_reject(args, kwargs, modfunc, lookup_attr):
seq, func = prepare_select_or_reject(args, kwargs, modfunc, lookup_attr)
if seq:
for item in seq:
if func(item):
yield item
FILTERS = {
'abs': abs,
'attr': do_attr,
'batch': do_batch,
'capitalize': do_capitalize,
'center': do_center,
'count': len,
'd': do_default,
'default': do_default,
'dictsort': do_dictsort,
'e': escape,
'escape': escape,
'filesizeformat': do_filesizeformat,
'first': do_first,
'float': do_float,
'forceescape': do_forceescape,
'format': do_format,
'groupby': do_groupby,
'indent': do_indent,
'int': do_int,
'join': do_join,
'last': do_last,
'length': len,
'list': do_list,
'lower': do_lower,
'map': do_map,
'min': do_min,
'max': do_max,
'pprint': do_pprint,
'random': do_random,
'reject': do_reject,
'rejectattr': do_rejectattr,
'replace': do_replace,
'reverse': do_reverse,
'round': do_round,
'safe': do_mark_safe,
'select': do_select,
'selectattr': do_selectattr,
'slice': do_slice,
'sort': do_sort,
'string': soft_unicode,
'striptags': do_striptags,
'sum': do_sum,
'title': do_title,
'trim': do_trim,
'truncate': do_truncate,
'unique': do_unique,
'upper': do_upper,
'urlencode': do_urlencode,
'urlize': do_urlize,
'wordcount': do_wordcount,
'wordwrap': do_wordwrap,
'xmlattr': do_xmlattr,
'tojson': do_tojson,
}