471 lines
14 KiB
Python
471 lines
14 KiB
Python
import gzip
|
|
import re
|
|
import secrets
|
|
import unicodedata
|
|
from gzip import GzipFile
|
|
from gzip import compress as gzip_compress
|
|
from io import BytesIO
|
|
|
|
from django.core.exceptions import SuspiciousFileOperation
|
|
from django.utils.functional import SimpleLazyObject, keep_lazy_text, lazy
|
|
from django.utils.regex_helper import _lazy_re_compile
|
|
from django.utils.translation import gettext as _
|
|
from django.utils.translation import gettext_lazy, pgettext
|
|
|
|
|
|
@keep_lazy_text
|
|
def capfirst(x):
|
|
"""Capitalize the first letter of a string."""
|
|
if not x:
|
|
return x
|
|
if not isinstance(x, str):
|
|
x = str(x)
|
|
return x[0].upper() + x[1:]
|
|
|
|
|
|
# Set up regular expressions
|
|
re_words = _lazy_re_compile(r"<[^>]+?>|([^<>\s]+)", re.S)
|
|
re_chars = _lazy_re_compile(r"<[^>]+?>|(.)", re.S)
|
|
re_tag = _lazy_re_compile(r"<(/)?(\S+?)(?:(\s*/)|\s.*?)?>", re.S)
|
|
re_newlines = _lazy_re_compile(r"\r\n|\r") # Used in normalize_newlines
|
|
re_camel_case = _lazy_re_compile(r"(((?<=[a-z])[A-Z])|([A-Z](?![A-Z]|$)))")
|
|
|
|
|
|
@keep_lazy_text
|
|
def wrap(text, width):
|
|
"""
|
|
A word-wrap function that preserves existing line breaks. Expects that
|
|
existing line breaks are posix newlines.
|
|
|
|
Preserve all white space except added line breaks consume the space on
|
|
which they break the line.
|
|
|
|
Don't wrap long words, thus the output text may have lines longer than
|
|
``width``.
|
|
"""
|
|
|
|
def _generator():
|
|
for line in text.splitlines(True): # True keeps trailing linebreaks
|
|
max_width = min((line.endswith("\n") and width + 1 or width), width)
|
|
while len(line) > max_width:
|
|
space = line[: max_width + 1].rfind(" ") + 1
|
|
if space == 0:
|
|
space = line.find(" ") + 1
|
|
if space == 0:
|
|
yield line
|
|
line = ""
|
|
break
|
|
yield "%s\n" % line[: space - 1]
|
|
line = line[space:]
|
|
max_width = min((line.endswith("\n") and width + 1 or width), width)
|
|
if line:
|
|
yield line
|
|
|
|
return "".join(_generator())
|
|
|
|
|
|
class Truncator(SimpleLazyObject):
|
|
"""
|
|
An object used to truncate text, either by characters or words.
|
|
|
|
When truncating HTML text (either chars or words), input will be limited to
|
|
at most `MAX_LENGTH_HTML` characters.
|
|
"""
|
|
|
|
# 5 million characters are approximately 4000 text pages or 3 web pages.
|
|
MAX_LENGTH_HTML = 5_000_000
|
|
|
|
def __init__(self, text):
|
|
super().__init__(lambda: str(text))
|
|
|
|
def add_truncation_text(self, text, truncate=None):
|
|
if truncate is None:
|
|
truncate = pgettext(
|
|
"String to return when truncating text", "%(truncated_text)s…"
|
|
)
|
|
if "%(truncated_text)s" in truncate:
|
|
return truncate % {"truncated_text": text}
|
|
# The truncation text didn't contain the %(truncated_text)s string
|
|
# replacement argument so just append it to the text.
|
|
if text.endswith(truncate):
|
|
# But don't append the truncation text if the current text already
|
|
# ends in this.
|
|
return text
|
|
return "%s%s" % (text, truncate)
|
|
|
|
def chars(self, num, truncate=None, html=False):
|
|
"""
|
|
Return the text truncated to be no longer than the specified number
|
|
of characters.
|
|
|
|
`truncate` specifies what should be used to notify that the string has
|
|
been truncated, defaulting to a translatable string of an ellipsis.
|
|
"""
|
|
self._setup()
|
|
length = int(num)
|
|
text = unicodedata.normalize("NFC", self._wrapped)
|
|
|
|
# Calculate the length to truncate to (max length - end_text length)
|
|
truncate_len = length
|
|
for char in self.add_truncation_text("", truncate):
|
|
if not unicodedata.combining(char):
|
|
truncate_len -= 1
|
|
if truncate_len == 0:
|
|
break
|
|
if html:
|
|
return self._truncate_html(length, truncate, text, truncate_len, False)
|
|
return self._text_chars(length, truncate, text, truncate_len)
|
|
|
|
def _text_chars(self, length, truncate, text, truncate_len):
|
|
"""Truncate a string after a certain number of chars."""
|
|
s_len = 0
|
|
end_index = None
|
|
for i, char in enumerate(text):
|
|
if unicodedata.combining(char):
|
|
# Don't consider combining characters
|
|
# as adding to the string length
|
|
continue
|
|
s_len += 1
|
|
if end_index is None and s_len > truncate_len:
|
|
end_index = i
|
|
if s_len > length:
|
|
# Return the truncated string
|
|
return self.add_truncation_text(text[: end_index or 0], truncate)
|
|
|
|
# Return the original string since no truncation was necessary
|
|
return text
|
|
|
|
def words(self, num, truncate=None, html=False):
|
|
"""
|
|
Truncate a string after a certain number of words. `truncate` specifies
|
|
what should be used to notify that the string has been truncated,
|
|
defaulting to ellipsis.
|
|
"""
|
|
self._setup()
|
|
length = int(num)
|
|
if html:
|
|
return self._truncate_html(length, truncate, self._wrapped, length, True)
|
|
return self._text_words(length, truncate)
|
|
|
|
def _text_words(self, length, truncate):
|
|
"""
|
|
Truncate a string after a certain number of words.
|
|
|
|
Strip newlines in the string.
|
|
"""
|
|
words = self._wrapped.split()
|
|
if len(words) > length:
|
|
words = words[:length]
|
|
return self.add_truncation_text(" ".join(words), truncate)
|
|
return " ".join(words)
|
|
|
|
def _truncate_html(self, length, truncate, text, truncate_len, words):
|
|
"""
|
|
Truncate HTML to a certain number of chars (not counting tags and
|
|
comments), or, if words is True, then to a certain number of words.
|
|
Close opened tags if they were correctly closed in the given HTML.
|
|
|
|
Preserve newlines in the HTML.
|
|
"""
|
|
if words and length <= 0:
|
|
return ""
|
|
|
|
size_limited = False
|
|
if len(text) > self.MAX_LENGTH_HTML:
|
|
text = text[: self.MAX_LENGTH_HTML]
|
|
size_limited = True
|
|
|
|
html4_singlets = (
|
|
"br",
|
|
"col",
|
|
"link",
|
|
"base",
|
|
"img",
|
|
"param",
|
|
"area",
|
|
"hr",
|
|
"input",
|
|
)
|
|
|
|
# Count non-HTML chars/words and keep note of open tags
|
|
pos = 0
|
|
end_text_pos = 0
|
|
current_len = 0
|
|
open_tags = []
|
|
|
|
regex = re_words if words else re_chars
|
|
|
|
while current_len <= length:
|
|
m = regex.search(text, pos)
|
|
if not m:
|
|
# Checked through whole string
|
|
break
|
|
pos = m.end(0)
|
|
if m[1]:
|
|
# It's an actual non-HTML word or char
|
|
current_len += 1
|
|
if current_len == truncate_len:
|
|
end_text_pos = pos
|
|
continue
|
|
# Check for tag
|
|
tag = re_tag.match(m[0])
|
|
if not tag or current_len >= truncate_len:
|
|
# Don't worry about non tags or tags after our truncate point
|
|
continue
|
|
closing_tag, tagname, self_closing = tag.groups()
|
|
# Element names are always case-insensitive
|
|
tagname = tagname.lower()
|
|
if self_closing or tagname in html4_singlets:
|
|
pass
|
|
elif closing_tag:
|
|
# Check for match in open tags list
|
|
try:
|
|
i = open_tags.index(tagname)
|
|
except ValueError:
|
|
pass
|
|
else:
|
|
# SGML: An end tag closes, back to the matching start tag,
|
|
# all unclosed intervening start tags with omitted end tags
|
|
open_tags = open_tags[i + 1 :]
|
|
else:
|
|
# Add it to the start of the open tags list
|
|
open_tags.insert(0, tagname)
|
|
|
|
truncate_text = self.add_truncation_text("", truncate)
|
|
|
|
if current_len <= length:
|
|
if size_limited and truncate_text:
|
|
text += truncate_text
|
|
return text
|
|
|
|
out = text[:end_text_pos]
|
|
if truncate_text:
|
|
out += truncate_text
|
|
# Close any tags still open
|
|
for tag in open_tags:
|
|
out += "</%s>" % tag
|
|
# Return string
|
|
return out
|
|
|
|
|
|
@keep_lazy_text
|
|
def get_valid_filename(name):
|
|
"""
|
|
Return the given string converted to a string that can be used for a clean
|
|
filename. Remove leading and trailing spaces; convert other spaces to
|
|
underscores; and remove anything that is not an alphanumeric, dash,
|
|
underscore, or dot.
|
|
>>> get_valid_filename("john's portrait in 2004.jpg")
|
|
'johns_portrait_in_2004.jpg'
|
|
"""
|
|
s = str(name).strip().replace(" ", "_")
|
|
s = re.sub(r"(?u)[^-\w.]", "", s)
|
|
if s in {"", ".", ".."}:
|
|
raise SuspiciousFileOperation("Could not derive file name from '%s'" % name)
|
|
return s
|
|
|
|
|
|
@keep_lazy_text
|
|
def get_text_list(list_, last_word=gettext_lazy("or")):
|
|
"""
|
|
>>> get_text_list(['a', 'b', 'c', 'd'])
|
|
'a, b, c or d'
|
|
>>> get_text_list(['a', 'b', 'c'], 'and')
|
|
'a, b and c'
|
|
>>> get_text_list(['a', 'b'], 'and')
|
|
'a and b'
|
|
>>> get_text_list(['a'])
|
|
'a'
|
|
>>> get_text_list([])
|
|
''
|
|
"""
|
|
if not list_:
|
|
return ""
|
|
if len(list_) == 1:
|
|
return str(list_[0])
|
|
return "%s %s %s" % (
|
|
# Translators: This string is used as a separator between list elements
|
|
_(", ").join(str(i) for i in list_[:-1]),
|
|
str(last_word),
|
|
str(list_[-1]),
|
|
)
|
|
|
|
|
|
@keep_lazy_text
|
|
def normalize_newlines(text):
|
|
"""Normalize CRLF and CR newlines to just LF."""
|
|
return re_newlines.sub("\n", str(text))
|
|
|
|
|
|
@keep_lazy_text
|
|
def phone2numeric(phone):
|
|
"""Convert a phone number with letters into its numeric equivalent."""
|
|
char2number = {
|
|
"a": "2",
|
|
"b": "2",
|
|
"c": "2",
|
|
"d": "3",
|
|
"e": "3",
|
|
"f": "3",
|
|
"g": "4",
|
|
"h": "4",
|
|
"i": "4",
|
|
"j": "5",
|
|
"k": "5",
|
|
"l": "5",
|
|
"m": "6",
|
|
"n": "6",
|
|
"o": "6",
|
|
"p": "7",
|
|
"q": "7",
|
|
"r": "7",
|
|
"s": "7",
|
|
"t": "8",
|
|
"u": "8",
|
|
"v": "8",
|
|
"w": "9",
|
|
"x": "9",
|
|
"y": "9",
|
|
"z": "9",
|
|
}
|
|
return "".join(char2number.get(c, c) for c in phone.lower())
|
|
|
|
|
|
def _get_random_filename(max_random_bytes):
|
|
return b"a" * secrets.randbelow(max_random_bytes)
|
|
|
|
|
|
def compress_string(s, *, max_random_bytes=None):
|
|
compressed_data = gzip_compress(s, compresslevel=6, mtime=0)
|
|
|
|
if not max_random_bytes:
|
|
return compressed_data
|
|
|
|
compressed_view = memoryview(compressed_data)
|
|
header = bytearray(compressed_view[:10])
|
|
header[3] = gzip.FNAME
|
|
|
|
filename = _get_random_filename(max_random_bytes) + b"\x00"
|
|
|
|
return bytes(header) + filename + compressed_view[10:]
|
|
|
|
|
|
class StreamingBuffer(BytesIO):
|
|
def read(self):
|
|
ret = self.getvalue()
|
|
self.seek(0)
|
|
self.truncate()
|
|
return ret
|
|
|
|
|
|
# Like compress_string, but for iterators of strings.
|
|
def compress_sequence(sequence, *, max_random_bytes=None):
|
|
buf = StreamingBuffer()
|
|
filename = _get_random_filename(max_random_bytes) if max_random_bytes else None
|
|
with GzipFile(
|
|
filename=filename, mode="wb", compresslevel=6, fileobj=buf, mtime=0
|
|
) as zfile:
|
|
# Output headers...
|
|
yield buf.read()
|
|
for item in sequence:
|
|
zfile.write(item)
|
|
data = buf.read()
|
|
if data:
|
|
yield data
|
|
yield buf.read()
|
|
|
|
|
|
# Expression to match some_token and some_token="with spaces" (and similarly
|
|
# for single-quoted strings).
|
|
smart_split_re = _lazy_re_compile(
|
|
r"""
|
|
((?:
|
|
[^\s'"]*
|
|
(?:
|
|
(?:"(?:[^"\\]|\\.)*" | '(?:[^'\\]|\\.)*')
|
|
[^\s'"]*
|
|
)+
|
|
) | \S+)
|
|
""",
|
|
re.VERBOSE,
|
|
)
|
|
|
|
|
|
def smart_split(text):
|
|
r"""
|
|
Generator that splits a string by spaces, leaving quoted phrases together.
|
|
Supports both single and double quotes, and supports escaping quotes with
|
|
backslashes. In the output, strings will keep their initial and trailing
|
|
quote marks and escaped quotes will remain escaped (the results can then
|
|
be further processed with unescape_string_literal()).
|
|
|
|
>>> list(smart_split(r'This is "a person\'s" test.'))
|
|
['This', 'is', '"a person\\\'s"', 'test.']
|
|
>>> list(smart_split(r"Another 'person\'s' test."))
|
|
['Another', "'person\\'s'", 'test.']
|
|
>>> list(smart_split(r'A "\"funky\" style" test.'))
|
|
['A', '"\\"funky\\" style"', 'test.']
|
|
"""
|
|
for bit in smart_split_re.finditer(str(text)):
|
|
yield bit[0]
|
|
|
|
|
|
@keep_lazy_text
|
|
def unescape_string_literal(s):
|
|
r"""
|
|
Convert quoted string literals to unquoted strings with escaped quotes and
|
|
backslashes unquoted::
|
|
|
|
>>> unescape_string_literal('"abc"')
|
|
'abc'
|
|
>>> unescape_string_literal("'abc'")
|
|
'abc'
|
|
>>> unescape_string_literal('"a \"bc\""')
|
|
'a "bc"'
|
|
>>> unescape_string_literal("'\'ab\' c'")
|
|
"'ab' c"
|
|
"""
|
|
if not s or s[0] not in "\"'" or s[-1] != s[0]:
|
|
raise ValueError("Not a string literal: %r" % s)
|
|
quote = s[0]
|
|
return s[1:-1].replace(r"\%s" % quote, quote).replace(r"\\", "\\")
|
|
|
|
|
|
@keep_lazy_text
|
|
def slugify(value, allow_unicode=False):
|
|
"""
|
|
Convert to ASCII if 'allow_unicode' is False. Convert spaces or repeated
|
|
dashes to single dashes. Remove characters that aren't alphanumerics,
|
|
underscores, or hyphens. Convert to lowercase. Also strip leading and
|
|
trailing whitespace, dashes, and underscores.
|
|
"""
|
|
value = str(value)
|
|
if allow_unicode:
|
|
value = unicodedata.normalize("NFKC", value)
|
|
else:
|
|
value = (
|
|
unicodedata.normalize("NFKD", value)
|
|
.encode("ascii", "ignore")
|
|
.decode("ascii")
|
|
)
|
|
value = re.sub(r"[^\w\s-]", "", value.lower())
|
|
return re.sub(r"[-\s]+", "-", value).strip("-_")
|
|
|
|
|
|
def camel_case_to_spaces(value):
|
|
"""
|
|
Split CamelCase and convert to lowercase. Strip surrounding whitespace.
|
|
"""
|
|
return re_camel_case.sub(r" \1", value).strip().lower()
|
|
|
|
|
|
def _format_lazy(format_string, *args, **kwargs):
|
|
"""
|
|
Apply str.format() on 'format_string' where format_string, args,
|
|
and/or kwargs might be lazy.
|
|
"""
|
|
return format_string.format(*args, **kwargs)
|
|
|
|
|
|
format_lazy = lazy(_format_lazy, str)
|