| # -*- coding: utf-8 -*- |
| """ |
| jinja2.utils |
| ~~~~~~~~~~~~ |
| |
| Utility functions. |
| |
| :copyright: (c) 2010 by the Jinja Team. |
| :license: BSD, see LICENSE for more details. |
| """ |
| import re |
| import errno |
| from collections import deque |
| from jinja2._compat import text_type, string_types, implements_iterator, \ |
| allocate_lock, url_quote |
| |
| |
| _word_split_re = re.compile(r'(\s+)') |
| _punctuation_re = re.compile( |
| '^(?P<lead>(?:%s)*)(?P<middle>.*?)(?P<trail>(?:%s)*)$' % ( |
| '|'.join(map(re.escape, ('(', '<', '<'))), |
| '|'.join(map(re.escape, ('.', ',', ')', '>', '\n', '>'))) |
| ) |
| ) |
| _simple_email_re = re.compile(r'^\S+@[a-zA-Z0-9._-]+\.[a-zA-Z0-9._-]+$') |
| _striptags_re = re.compile(r'(<!--.*?-->|<[^>]*>)') |
| _entity_re = re.compile(r'&([^;]+);') |
| _letters = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ' |
| _digits = '0123456789' |
| |
| # special singleton representing missing values for the runtime |
| missing = type('MissingType', (), {'__repr__': lambda x: 'missing'})() |
| |
| # internal code |
| internal_code = set() |
| |
| concat = u''.join |
| |
| |
| def contextfunction(f): |
| """This decorator can be used to mark a function or method context callable. |
| A context callable is passed the active :class:`Context` as first argument when |
| called from the template. This is useful if a function wants to get access |
| to the context or functions provided on the context object. For example |
| a function that returns a sorted list of template variables the current |
| template exports could look like this:: |
| |
| @contextfunction |
| def get_exported_names(context): |
| return sorted(context.exported_vars) |
| """ |
| f.contextfunction = True |
| return f |
| |
| |
| def evalcontextfunction(f): |
| """This decorator can be used to mark a function or method as an eval |
| context callable. This is similar to the :func:`contextfunction` |
| but instead of passing the context, an evaluation context object is |
| passed. For more information about the eval context, see |
| :ref:`eval-context`. |
| |
| .. versionadded:: 2.4 |
| """ |
| f.evalcontextfunction = True |
| return f |
| |
| |
| def environmentfunction(f): |
| """This decorator can be used to mark a function or method as environment |
| callable. This decorator works exactly like the :func:`contextfunction` |
| decorator just that the first argument is the active :class:`Environment` |
| and not context. |
| """ |
| f.environmentfunction = True |
| return f |
| |
| |
| def internalcode(f): |
| """Marks the function as internally used""" |
| internal_code.add(f.__code__) |
| return f |
| |
| |
| def is_undefined(obj): |
| """Check if the object passed is undefined. This does nothing more than |
| performing an instance check against :class:`Undefined` but looks nicer. |
| This can be used for custom filters or tests that want to react to |
| undefined variables. For example a custom default filter can look like |
| this:: |
| |
| def default(var, default=''): |
| if is_undefined(var): |
| return default |
| return var |
| """ |
| from jinja2.runtime import Undefined |
| return isinstance(obj, Undefined) |
| |
| |
| def consume(iterable): |
| """Consumes an iterable without doing anything with it.""" |
| for event in iterable: |
| pass |
| |
| |
| def clear_caches(): |
| """Jinja2 keeps internal caches for environments and lexers. These are |
| used so that Jinja2 doesn't have to recreate environments and lexers all |
| the time. Normally you don't have to care about that but if you are |
| messuring memory consumption you may want to clean the caches. |
| """ |
| from jinja2.environment import _spontaneous_environments |
| from jinja2.lexer import _lexer_cache |
| _spontaneous_environments.clear() |
| _lexer_cache.clear() |
| |
| |
| def import_string(import_name, silent=False): |
| """Imports an object based on a string. This is useful if you want to |
| use import paths as endpoints or something similar. An import path can |
| be specified either in dotted notation (``xml.sax.saxutils.escape``) |
| or with a colon as object delimiter (``xml.sax.saxutils:escape``). |
| |
| If the `silent` is True the return value will be `None` if the import |
| fails. |
| |
| :return: imported object |
| """ |
| try: |
| if ':' in import_name: |
| module, obj = import_name.split(':', 1) |
| elif '.' in import_name: |
| items = import_name.split('.') |
| module = '.'.join(items[:-1]) |
| obj = items[-1] |
| else: |
| return __import__(import_name) |
| return getattr(__import__(module, None, None, [obj]), obj) |
| except (ImportError, AttributeError): |
| if not silent: |
| raise |
| |
| |
| def open_if_exists(filename, mode='rb'): |
| """Returns a file descriptor for the filename if that file exists, |
| otherwise `None`. |
| """ |
| try: |
| return open(filename, mode) |
| except IOError as e: |
| if e.errno not in (errno.ENOENT, errno.EISDIR): |
| raise |
| |
| |
| def object_type_repr(obj): |
| """Returns the name of the object's type. For some recognized |
| singletons the name of the object is returned instead. (For |
| example for `None` and `Ellipsis`). |
| """ |
| if obj is None: |
| return 'None' |
| elif obj is Ellipsis: |
| return 'Ellipsis' |
| # __builtin__ in 2.x, builtins in 3.x |
| if obj.__class__.__module__ in ('__builtin__', 'builtins'): |
| name = obj.__class__.__name__ |
| else: |
| name = obj.__class__.__module__ + '.' + obj.__class__.__name__ |
| return '%s object' % name |
| |
| |
| def pformat(obj, verbose=False): |
| """Prettyprint an object. Either use the `pretty` library or the |
| builtin `pprint`. |
| """ |
| try: |
| from pretty import pretty |
| return pretty(obj, verbose=verbose) |
| except ImportError: |
| from pprint import pformat |
| return pformat(obj) |
| |
| |
| def urlize(text, trim_url_limit=None, nofollow=False): |
| """Converts any URLs in text into clickable links. Works on http://, |
| https:// and www. links. Links can have trailing punctuation (periods, |
| commas, close-parens) and leading punctuation (opening parens) and |
| it'll still do the right thing. |
| |
| If trim_url_limit is not None, the URLs in link text will be limited |
| to trim_url_limit characters. |
| |
| If nofollow is True, the URLs in link text will get a rel="nofollow" |
| attribute. |
| """ |
| trim_url = lambda x, limit=trim_url_limit: limit is not None \ |
| and (x[:limit] + (len(x) >=limit and '...' |
| or '')) or x |
| words = _word_split_re.split(text_type(escape(text))) |
| nofollow_attr = nofollow and ' rel="nofollow"' or '' |
| for i, word in enumerate(words): |
| match = _punctuation_re.match(word) |
| if match: |
| lead, middle, trail = match.groups() |
| if middle.startswith('www.') or ( |
| '@' not in middle and |
| not middle.startswith('http://') and |
| not middle.startswith('https://') and |
| len(middle) > 0 and |
| middle[0] in _letters + _digits and ( |
| middle.endswith('.org') or |
| middle.endswith('.net') or |
| middle.endswith('.com') |
| )): |
| middle = '<a href="http://%s"%s>%s</a>' % (middle, |
| nofollow_attr, trim_url(middle)) |
| if middle.startswith('http://') or \ |
| middle.startswith('https://'): |
| middle = '<a href="%s"%s>%s</a>' % (middle, |
| nofollow_attr, trim_url(middle)) |
| if '@' in middle and not middle.startswith('www.') and \ |
| not ':' in middle and _simple_email_re.match(middle): |
| middle = '<a href="mailto:%s">%s</a>' % (middle, middle) |
| if lead + middle + trail != word: |
| words[i] = lead + middle + trail |
| return u''.join(words) |
| |
| |
| def generate_lorem_ipsum(n=5, html=True, min=20, max=100): |
| """Generate some lorem impsum for the template.""" |
| from jinja2.constants import LOREM_IPSUM_WORDS |
| from random import choice, randrange |
| words = LOREM_IPSUM_WORDS.split() |
| result = [] |
| |
| for _ in range(n): |
| next_capitalized = True |
| last_comma = last_fullstop = 0 |
| word = None |
| last = None |
| p = [] |
| |
| # each paragraph contains out of 20 to 100 words. |
| for idx, _ in enumerate(range(randrange(min, max))): |
| while True: |
| word = choice(words) |
| if word != last: |
| last = word |
| break |
| if next_capitalized: |
| word = word.capitalize() |
| next_capitalized = False |
| # add commas |
| if idx - randrange(3, 8) > last_comma: |
| last_comma = idx |
| last_fullstop += 2 |
| word += ',' |
| # add end of sentences |
| if idx - randrange(10, 20) > last_fullstop: |
| last_comma = last_fullstop = idx |
| word += '.' |
| next_capitalized = True |
| p.append(word) |
| |
| # ensure that the paragraph ends with a dot. |
| p = u' '.join(p) |
| if p.endswith(','): |
| p = p[:-1] + '.' |
| elif not p.endswith('.'): |
| p += '.' |
| result.append(p) |
| |
| if not html: |
| return u'\n\n'.join(result) |
| return Markup(u'\n'.join(u'<p>%s</p>' % escape(x) for x in result)) |
| |
| |
| def unicode_urlencode(obj, charset='utf-8'): |
| """URL escapes a single bytestring or unicode string with the |
| given charset if applicable to URL safe quoting under all rules |
| that need to be considered under all supported Python versions. |
| |
| If non strings are provided they are converted to their unicode |
| representation first. |
| """ |
| if not isinstance(obj, string_types): |
| obj = text_type(obj) |
| if isinstance(obj, text_type): |
| obj = obj.encode(charset) |
| return text_type(url_quote(obj)) |
| |
| |
| class LRUCache(object): |
| """A simple LRU Cache implementation.""" |
| |
| # this is fast for small capacities (something below 1000) but doesn't |
| # scale. But as long as it's only used as storage for templates this |
| # won't do any harm. |
| |
| def __init__(self, capacity): |
| self.capacity = capacity |
| self._mapping = {} |
| self._queue = deque() |
| self._postinit() |
| |
| def _postinit(self): |
| # alias all queue methods for faster lookup |
| self._popleft = self._queue.popleft |
| self._pop = self._queue.pop |
| self._remove = self._queue.remove |
| self._wlock = allocate_lock() |
| self._append = self._queue.append |
| |
| def __getstate__(self): |
| return { |
| 'capacity': self.capacity, |
| '_mapping': self._mapping, |
| '_queue': self._queue |
| } |
| |
| def __setstate__(self, d): |
| self.__dict__.update(d) |
| self._postinit() |
| |
| def __getnewargs__(self): |
| return (self.capacity,) |
| |
| def copy(self): |
| """Return a shallow copy of the instance.""" |
| rv = self.__class__(self.capacity) |
| rv._mapping.update(self._mapping) |
| rv._queue = deque(self._queue) |
| return rv |
| |
| def get(self, key, default=None): |
| """Return an item from the cache dict or `default`""" |
| try: |
| return self[key] |
| except KeyError: |
| return default |
| |
| def setdefault(self, key, default=None): |
| """Set `default` if the key is not in the cache otherwise |
| leave unchanged. Return the value of this key. |
| """ |
| self._wlock.acquire() |
| try: |
| try: |
| return self[key] |
| except KeyError: |
| self[key] = default |
| return default |
| finally: |
| self._wlock.release() |
| |
| def clear(self): |
| """Clear the cache.""" |
| self._wlock.acquire() |
| try: |
| self._mapping.clear() |
| self._queue.clear() |
| finally: |
| self._wlock.release() |
| |
| def __contains__(self, key): |
| """Check if a key exists in this cache.""" |
| return key in self._mapping |
| |
| def __len__(self): |
| """Return the current size of the cache.""" |
| return len(self._mapping) |
| |
| def __repr__(self): |
| return '<%s %r>' % ( |
| self.__class__.__name__, |
| self._mapping |
| ) |
| |
| def __getitem__(self, key): |
| """Get an item from the cache. Moves the item up so that it has the |
| highest priority then. |
| |
| Raise a `KeyError` if it does not exist. |
| """ |
| self._wlock.acquire() |
| try: |
| rv = self._mapping[key] |
| if self._queue[-1] != key: |
| try: |
| self._remove(key) |
| except ValueError: |
| # if something removed the key from the container |
| # when we read, ignore the ValueError that we would |
| # get otherwise. |
| pass |
| self._append(key) |
| return rv |
| finally: |
| self._wlock.release() |
| |
| def __setitem__(self, key, value): |
| """Sets the value for an item. Moves the item up so that it |
| has the highest priority then. |
| """ |
| self._wlock.acquire() |
| try: |
| if key in self._mapping: |
| self._remove(key) |
| elif len(self._mapping) == self.capacity: |
| del self._mapping[self._popleft()] |
| self._append(key) |
| self._mapping[key] = value |
| finally: |
| self._wlock.release() |
| |
| def __delitem__(self, key): |
| """Remove an item from the cache dict. |
| Raise a `KeyError` if it does not exist. |
| """ |
| self._wlock.acquire() |
| try: |
| del self._mapping[key] |
| try: |
| self._remove(key) |
| except ValueError: |
| # __getitem__ is not locked, it might happen |
| pass |
| finally: |
| self._wlock.release() |
| |
| def items(self): |
| """Return a list of items.""" |
| result = [(key, self._mapping[key]) for key in list(self._queue)] |
| result.reverse() |
| return result |
| |
| def iteritems(self): |
| """Iterate over all items.""" |
| return iter(self.items()) |
| |
| def values(self): |
| """Return a list of all values.""" |
| return [x[1] for x in self.items()] |
| |
| def itervalue(self): |
| """Iterate over all values.""" |
| return iter(self.values()) |
| |
| def keys(self): |
| """Return a list of all keys ordered by most recent usage.""" |
| return list(self) |
| |
| def iterkeys(self): |
| """Iterate over all keys in the cache dict, ordered by |
| the most recent usage. |
| """ |
| return reversed(tuple(self._queue)) |
| |
| __iter__ = iterkeys |
| |
| def __reversed__(self): |
| """Iterate over the values in the cache dict, oldest items |
| coming first. |
| """ |
| return iter(tuple(self._queue)) |
| |
| __copy__ = copy |
| |
| |
| # register the LRU cache as mutable mapping if possible |
| try: |
| from collections import MutableMapping |
| MutableMapping.register(LRUCache) |
| except ImportError: |
| pass |
| |
| |
| @implements_iterator |
| class Cycler(object): |
| """A cycle helper for templates.""" |
| |
| def __init__(self, *items): |
| if not items: |
| raise RuntimeError('at least one item has to be provided') |
| self.items = items |
| self.reset() |
| |
| def reset(self): |
| """Resets the cycle.""" |
| self.pos = 0 |
| |
| @property |
| def current(self): |
| """Returns the current item.""" |
| return self.items[self.pos] |
| |
| def __next__(self): |
| """Goes one item ahead and returns it.""" |
| rv = self.current |
| self.pos = (self.pos + 1) % len(self.items) |
| return rv |
| |
| |
| class Joiner(object): |
| """A joining helper for templates.""" |
| |
| def __init__(self, sep=u', '): |
| self.sep = sep |
| self.used = False |
| |
| def __call__(self): |
| if not self.used: |
| self.used = True |
| return u'' |
| return self.sep |
| |
| |
| # Imported here because that's where it was in the past |
| from markupsafe import Markup, escape, soft_unicode |
