regex – Tools for representing MongoDB regular expressions

New in version 2.7.

Tools for representing MongoDB regular expressions.

class bson.regex.Regex(pattern, flags=0)

BSON regular expression data.

This class is useful to store and retrieve regular expressions that are incompatible with Python’s regular expression dialect.

• classmethod from_native(regex)

  Convert a Python regular expression into a Regex instance.

  Note that in Python 3, a regular expression compiled from a str has the re.UNICODE flag set. If it is undesirable to store this flag in a BSON regular expression, unset it first:

  >>> pattern = re.compile('.*')
  >>> regex = Regex.from_native(pattern)
  >>> regex.flags ^= re.UNICODE
  >>> db.collection.insert({'pattern': regex})

  Parameters:	regex: A regular expression object from re.compile().

  Warning

  Python regular expressions use a different syntax and different set of flags than MongoDB, which uses PCRE. A regular expression retrieved from the server may not compile in Python, or may match a different set of strings in Python than when used in a MongoDB query.

• try_compile()

  Compile this Regex as a Python regular expression.

  Warning

  Python regular expressions use a different syntax and different set of flags than MongoDB, which uses PCRE. A regular expression retrieved from the server may not compile in Python, or may match a different set of strings in Python than when used in a MongoDB query. try_compile() may raise re.error.