OLD | NEW |
(Empty) | |
| 1 # -*- coding: utf-8 -*- |
| 2 """ |
| 3 jinja2.utils |
| 4 ~~~~~~~~~~~~ |
| 5 |
| 6 Utility functions. |
| 7 |
| 8 :copyright: (c) 2010 by the Jinja Team. |
| 9 :license: BSD, see LICENSE for more details. |
| 10 """ |
| 11 import re |
| 12 import errno |
| 13 from collections import deque |
| 14 from jinja2._compat import text_type, string_types, implements_iterator, \ |
| 15 allocate_lock, url_quote |
| 16 |
| 17 |
| 18 _word_split_re = re.compile(r'(\s+)') |
| 19 _punctuation_re = re.compile( |
| 20 '^(?P<lead>(?:%s)*)(?P<middle>.*?)(?P<trail>(?:%s)*)$' % ( |
| 21 '|'.join(map(re.escape, ('(', '<', '<'))), |
| 22 '|'.join(map(re.escape, ('.', ',', ')', '>', '\n', '>'))) |
| 23 ) |
| 24 ) |
| 25 _simple_email_re = re.compile(r'^\S+@[a-zA-Z0-9._-]+\.[a-zA-Z0-9._-]+$') |
| 26 _striptags_re = re.compile(r'(<!--.*?-->|<[^>]*>)') |
| 27 _entity_re = re.compile(r'&([^;]+);') |
| 28 _letters = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ' |
| 29 _digits = '0123456789' |
| 30 |
| 31 # special singleton representing missing values for the runtime |
| 32 missing = type('MissingType', (), {'__repr__': lambda x: 'missing'})() |
| 33 |
| 34 # internal code |
| 35 internal_code = set() |
| 36 |
| 37 concat = u''.join |
| 38 |
| 39 |
| 40 def contextfunction(f): |
| 41 """This decorator can be used to mark a function or method context callable. |
| 42 A context callable is passed the active :class:`Context` as first argument w
hen |
| 43 called from the template. This is useful if a function wants to get access |
| 44 to the context or functions provided on the context object. For example |
| 45 a function that returns a sorted list of template variables the current |
| 46 template exports could look like this:: |
| 47 |
| 48 @contextfunction |
| 49 def get_exported_names(context): |
| 50 return sorted(context.exported_vars) |
| 51 """ |
| 52 f.contextfunction = True |
| 53 return f |
| 54 |
| 55 |
| 56 def evalcontextfunction(f): |
| 57 """This decorator can be used to mark a function or method as an eval |
| 58 context callable. This is similar to the :func:`contextfunction` |
| 59 but instead of passing the context, an evaluation context object is |
| 60 passed. For more information about the eval context, see |
| 61 :ref:`eval-context`. |
| 62 |
| 63 .. versionadded:: 2.4 |
| 64 """ |
| 65 f.evalcontextfunction = True |
| 66 return f |
| 67 |
| 68 |
| 69 def environmentfunction(f): |
| 70 """This decorator can be used to mark a function or method as environment |
| 71 callable. This decorator works exactly like the :func:`contextfunction` |
| 72 decorator just that the first argument is the active :class:`Environment` |
| 73 and not context. |
| 74 """ |
| 75 f.environmentfunction = True |
| 76 return f |
| 77 |
| 78 |
| 79 def internalcode(f): |
| 80 """Marks the function as internally used""" |
| 81 internal_code.add(f.__code__) |
| 82 return f |
| 83 |
| 84 |
| 85 def is_undefined(obj): |
| 86 """Check if the object passed is undefined. This does nothing more than |
| 87 performing an instance check against :class:`Undefined` but looks nicer. |
| 88 This can be used for custom filters or tests that want to react to |
| 89 undefined variables. For example a custom default filter can look like |
| 90 this:: |
| 91 |
| 92 def default(var, default=''): |
| 93 if is_undefined(var): |
| 94 return default |
| 95 return var |
| 96 """ |
| 97 from jinja2.runtime import Undefined |
| 98 return isinstance(obj, Undefined) |
| 99 |
| 100 |
| 101 def consume(iterable): |
| 102 """Consumes an iterable without doing anything with it.""" |
| 103 for event in iterable: |
| 104 pass |
| 105 |
| 106 |
| 107 def clear_caches(): |
| 108 """Jinja2 keeps internal caches for environments and lexers. These are |
| 109 used so that Jinja2 doesn't have to recreate environments and lexers all |
| 110 the time. Normally you don't have to care about that but if you are |
| 111 messuring memory consumption you may want to clean the caches. |
| 112 """ |
| 113 from jinja2.environment import _spontaneous_environments |
| 114 from jinja2.lexer import _lexer_cache |
| 115 _spontaneous_environments.clear() |
| 116 _lexer_cache.clear() |
| 117 |
| 118 |
| 119 def import_string(import_name, silent=False): |
| 120 """Imports an object based on a string. This is useful if you want to |
| 121 use import paths as endpoints or something similar. An import path can |
| 122 be specified either in dotted notation (``xml.sax.saxutils.escape``) |
| 123 or with a colon as object delimiter (``xml.sax.saxutils:escape``). |
| 124 |
| 125 If the `silent` is True the return value will be `None` if the import |
| 126 fails. |
| 127 |
| 128 :return: imported object |
| 129 """ |
| 130 try: |
| 131 if ':' in import_name: |
| 132 module, obj = import_name.split(':', 1) |
| 133 elif '.' in import_name: |
| 134 items = import_name.split('.') |
| 135 module = '.'.join(items[:-1]) |
| 136 obj = items[-1] |
| 137 else: |
| 138 return __import__(import_name) |
| 139 return getattr(__import__(module, None, None, [obj]), obj) |
| 140 except (ImportError, AttributeError): |
| 141 if not silent: |
| 142 raise |
| 143 |
| 144 |
| 145 def open_if_exists(filename, mode='rb'): |
| 146 """Returns a file descriptor for the filename if that file exists, |
| 147 otherwise `None`. |
| 148 """ |
| 149 try: |
| 150 return open(filename, mode) |
| 151 except IOError as e: |
| 152 if e.errno not in (errno.ENOENT, errno.EISDIR): |
| 153 raise |
| 154 |
| 155 |
| 156 def object_type_repr(obj): |
| 157 """Returns the name of the object's type. For some recognized |
| 158 singletons the name of the object is returned instead. (For |
| 159 example for `None` and `Ellipsis`). |
| 160 """ |
| 161 if obj is None: |
| 162 return 'None' |
| 163 elif obj is Ellipsis: |
| 164 return 'Ellipsis' |
| 165 # __builtin__ in 2.x, builtins in 3.x |
| 166 if obj.__class__.__module__ in ('__builtin__', 'builtins'): |
| 167 name = obj.__class__.__name__ |
| 168 else: |
| 169 name = obj.__class__.__module__ + '.' + obj.__class__.__name__ |
| 170 return '%s object' % name |
| 171 |
| 172 |
| 173 def pformat(obj, verbose=False): |
| 174 """Prettyprint an object. Either use the `pretty` library or the |
| 175 builtin `pprint`. |
| 176 """ |
| 177 try: |
| 178 from pretty import pretty |
| 179 return pretty(obj, verbose=verbose) |
| 180 except ImportError: |
| 181 from pprint import pformat |
| 182 return pformat(obj) |
| 183 |
| 184 |
| 185 def urlize(text, trim_url_limit=None, nofollow=False): |
| 186 """Converts any URLs in text into clickable links. Works on http://, |
| 187 https:// and www. links. Links can have trailing punctuation (periods, |
| 188 commas, close-parens) and leading punctuation (opening parens) and |
| 189 it'll still do the right thing. |
| 190 |
| 191 If trim_url_limit is not None, the URLs in link text will be limited |
| 192 to trim_url_limit characters. |
| 193 |
| 194 If nofollow is True, the URLs in link text will get a rel="nofollow" |
| 195 attribute. |
| 196 """ |
| 197 trim_url = lambda x, limit=trim_url_limit: limit is not None \ |
| 198 and (x[:limit] + (len(x) >=limit and '...' |
| 199 or '')) or x |
| 200 words = _word_split_re.split(text_type(escape(text))) |
| 201 nofollow_attr = nofollow and ' rel="nofollow"' or '' |
| 202 for i, word in enumerate(words): |
| 203 match = _punctuation_re.match(word) |
| 204 if match: |
| 205 lead, middle, trail = match.groups() |
| 206 if middle.startswith('www.') or ( |
| 207 '@' not in middle and |
| 208 not middle.startswith('http://') and |
| 209 not middle.startswith('https://') and |
| 210 len(middle) > 0 and |
| 211 middle[0] in _letters + _digits and ( |
| 212 middle.endswith('.org') or |
| 213 middle.endswith('.net') or |
| 214 middle.endswith('.com') |
| 215 )): |
| 216 middle = '<a href="http://%s"%s>%s</a>' % (middle, |
| 217 nofollow_attr, trim_url(middle)) |
| 218 if middle.startswith('http://') or \ |
| 219 middle.startswith('https://'): |
| 220 middle = '<a href="%s"%s>%s</a>' % (middle, |
| 221 nofollow_attr, trim_url(middle)) |
| 222 if '@' in middle and not middle.startswith('www.') and \ |
| 223 not ':' in middle and _simple_email_re.match(middle): |
| 224 middle = '<a href="mailto:%s">%s</a>' % (middle, middle) |
| 225 if lead + middle + trail != word: |
| 226 words[i] = lead + middle + trail |
| 227 return u''.join(words) |
| 228 |
| 229 |
| 230 def generate_lorem_ipsum(n=5, html=True, min=20, max=100): |
| 231 """Generate some lorem impsum for the template.""" |
| 232 from jinja2.constants import LOREM_IPSUM_WORDS |
| 233 from random import choice, randrange |
| 234 words = LOREM_IPSUM_WORDS.split() |
| 235 result = [] |
| 236 |
| 237 for _ in range(n): |
| 238 next_capitalized = True |
| 239 last_comma = last_fullstop = 0 |
| 240 word = None |
| 241 last = None |
| 242 p = [] |
| 243 |
| 244 # each paragraph contains out of 20 to 100 words. |
| 245 for idx, _ in enumerate(range(randrange(min, max))): |
| 246 while True: |
| 247 word = choice(words) |
| 248 if word != last: |
| 249 last = word |
| 250 break |
| 251 if next_capitalized: |
| 252 word = word.capitalize() |
| 253 next_capitalized = False |
| 254 # add commas |
| 255 if idx - randrange(3, 8) > last_comma: |
| 256 last_comma = idx |
| 257 last_fullstop += 2 |
| 258 word += ',' |
| 259 # add end of sentences |
| 260 if idx - randrange(10, 20) > last_fullstop: |
| 261 last_comma = last_fullstop = idx |
| 262 word += '.' |
| 263 next_capitalized = True |
| 264 p.append(word) |
| 265 |
| 266 # ensure that the paragraph ends with a dot. |
| 267 p = u' '.join(p) |
| 268 if p.endswith(','): |
| 269 p = p[:-1] + '.' |
| 270 elif not p.endswith('.'): |
| 271 p += '.' |
| 272 result.append(p) |
| 273 |
| 274 if not html: |
| 275 return u'\n\n'.join(result) |
| 276 return Markup(u'\n'.join(u'<p>%s</p>' % escape(x) for x in result)) |
| 277 |
| 278 |
| 279 def unicode_urlencode(obj, charset='utf-8'): |
| 280 """URL escapes a single bytestring or unicode string with the |
| 281 given charset if applicable to URL safe quoting under all rules |
| 282 that need to be considered under all supported Python versions. |
| 283 |
| 284 If non strings are provided they are converted to their unicode |
| 285 representation first. |
| 286 """ |
| 287 if not isinstance(obj, string_types): |
| 288 obj = text_type(obj) |
| 289 if isinstance(obj, text_type): |
| 290 obj = obj.encode(charset) |
| 291 return text_type(url_quote(obj)) |
| 292 |
| 293 |
| 294 class LRUCache(object): |
| 295 """A simple LRU Cache implementation.""" |
| 296 |
| 297 # this is fast for small capacities (something below 1000) but doesn't |
| 298 # scale. But as long as it's only used as storage for templates this |
| 299 # won't do any harm. |
| 300 |
| 301 def __init__(self, capacity): |
| 302 self.capacity = capacity |
| 303 self._mapping = {} |
| 304 self._queue = deque() |
| 305 self._postinit() |
| 306 |
| 307 def _postinit(self): |
| 308 # alias all queue methods for faster lookup |
| 309 self._popleft = self._queue.popleft |
| 310 self._pop = self._queue.pop |
| 311 self._remove = self._queue.remove |
| 312 self._wlock = allocate_lock() |
| 313 self._append = self._queue.append |
| 314 |
| 315 def __getstate__(self): |
| 316 return { |
| 317 'capacity': self.capacity, |
| 318 '_mapping': self._mapping, |
| 319 '_queue': self._queue |
| 320 } |
| 321 |
| 322 def __setstate__(self, d): |
| 323 self.__dict__.update(d) |
| 324 self._postinit() |
| 325 |
| 326 def __getnewargs__(self): |
| 327 return (self.capacity,) |
| 328 |
| 329 def copy(self): |
| 330 """Return a shallow copy of the instance.""" |
| 331 rv = self.__class__(self.capacity) |
| 332 rv._mapping.update(self._mapping) |
| 333 rv._queue = deque(self._queue) |
| 334 return rv |
| 335 |
| 336 def get(self, key, default=None): |
| 337 """Return an item from the cache dict or `default`""" |
| 338 try: |
| 339 return self[key] |
| 340 except KeyError: |
| 341 return default |
| 342 |
| 343 def setdefault(self, key, default=None): |
| 344 """Set `default` if the key is not in the cache otherwise |
| 345 leave unchanged. Return the value of this key. |
| 346 """ |
| 347 self._wlock.acquire() |
| 348 try: |
| 349 try: |
| 350 return self[key] |
| 351 except KeyError: |
| 352 self[key] = default |
| 353 return default |
| 354 finally: |
| 355 self._wlock.release() |
| 356 |
| 357 def clear(self): |
| 358 """Clear the cache.""" |
| 359 self._wlock.acquire() |
| 360 try: |
| 361 self._mapping.clear() |
| 362 self._queue.clear() |
| 363 finally: |
| 364 self._wlock.release() |
| 365 |
| 366 def __contains__(self, key): |
| 367 """Check if a key exists in this cache.""" |
| 368 return key in self._mapping |
| 369 |
| 370 def __len__(self): |
| 371 """Return the current size of the cache.""" |
| 372 return len(self._mapping) |
| 373 |
| 374 def __repr__(self): |
| 375 return '<%s %r>' % ( |
| 376 self.__class__.__name__, |
| 377 self._mapping |
| 378 ) |
| 379 |
| 380 def __getitem__(self, key): |
| 381 """Get an item from the cache. Moves the item up so that it has the |
| 382 highest priority then. |
| 383 |
| 384 Raise a `KeyError` if it does not exist. |
| 385 """ |
| 386 self._wlock.acquire() |
| 387 try: |
| 388 rv = self._mapping[key] |
| 389 if self._queue[-1] != key: |
| 390 try: |
| 391 self._remove(key) |
| 392 except ValueError: |
| 393 # if something removed the key from the container |
| 394 # when we read, ignore the ValueError that we would |
| 395 # get otherwise. |
| 396 pass |
| 397 self._append(key) |
| 398 return rv |
| 399 finally: |
| 400 self._wlock.release() |
| 401 |
| 402 def __setitem__(self, key, value): |
| 403 """Sets the value for an item. Moves the item up so that it |
| 404 has the highest priority then. |
| 405 """ |
| 406 self._wlock.acquire() |
| 407 try: |
| 408 if key in self._mapping: |
| 409 self._remove(key) |
| 410 elif len(self._mapping) == self.capacity: |
| 411 del self._mapping[self._popleft()] |
| 412 self._append(key) |
| 413 self._mapping[key] = value |
| 414 finally: |
| 415 self._wlock.release() |
| 416 |
| 417 def __delitem__(self, key): |
| 418 """Remove an item from the cache dict. |
| 419 Raise a `KeyError` if it does not exist. |
| 420 """ |
| 421 self._wlock.acquire() |
| 422 try: |
| 423 del self._mapping[key] |
| 424 try: |
| 425 self._remove(key) |
| 426 except ValueError: |
| 427 # __getitem__ is not locked, it might happen |
| 428 pass |
| 429 finally: |
| 430 self._wlock.release() |
| 431 |
| 432 def items(self): |
| 433 """Return a list of items.""" |
| 434 result = [(key, self._mapping[key]) for key in list(self._queue)] |
| 435 result.reverse() |
| 436 return result |
| 437 |
| 438 def iteritems(self): |
| 439 """Iterate over all items.""" |
| 440 return iter(self.items()) |
| 441 |
| 442 def values(self): |
| 443 """Return a list of all values.""" |
| 444 return [x[1] for x in self.items()] |
| 445 |
| 446 def itervalue(self): |
| 447 """Iterate over all values.""" |
| 448 return iter(self.values()) |
| 449 |
| 450 def keys(self): |
| 451 """Return a list of all keys ordered by most recent usage.""" |
| 452 return list(self) |
| 453 |
| 454 def iterkeys(self): |
| 455 """Iterate over all keys in the cache dict, ordered by |
| 456 the most recent usage. |
| 457 """ |
| 458 return reversed(tuple(self._queue)) |
| 459 |
| 460 __iter__ = iterkeys |
| 461 |
| 462 def __reversed__(self): |
| 463 """Iterate over the values in the cache dict, oldest items |
| 464 coming first. |
| 465 """ |
| 466 return iter(tuple(self._queue)) |
| 467 |
| 468 __copy__ = copy |
| 469 |
| 470 |
| 471 # register the LRU cache as mutable mapping if possible |
| 472 try: |
| 473 from collections import MutableMapping |
| 474 MutableMapping.register(LRUCache) |
| 475 except ImportError: |
| 476 pass |
| 477 |
| 478 |
| 479 @implements_iterator |
| 480 class Cycler(object): |
| 481 """A cycle helper for templates.""" |
| 482 |
| 483 def __init__(self, *items): |
| 484 if not items: |
| 485 raise RuntimeError('at least one item has to be provided') |
| 486 self.items = items |
| 487 self.reset() |
| 488 |
| 489 def reset(self): |
| 490 """Resets the cycle.""" |
| 491 self.pos = 0 |
| 492 |
| 493 @property |
| 494 def current(self): |
| 495 """Returns the current item.""" |
| 496 return self.items[self.pos] |
| 497 |
| 498 def __next__(self): |
| 499 """Goes one item ahead and returns it.""" |
| 500 rv = self.current |
| 501 self.pos = (self.pos + 1) % len(self.items) |
| 502 return rv |
| 503 |
| 504 |
| 505 class Joiner(object): |
| 506 """A joining helper for templates.""" |
| 507 |
| 508 def __init__(self, sep=u', '): |
| 509 self.sep = sep |
| 510 self.used = False |
| 511 |
| 512 def __call__(self): |
| 513 if not self.used: |
| 514 self.used = True |
| 515 return u'' |
| 516 return self.sep |
| 517 |
| 518 |
| 519 # Imported here because that's where it was in the past |
| 520 from markupsafe import Markup, escape, soft_unicode |
OLD | NEW |