Simple Log Service:Regular expression functions

Extracts a value that matches a regular expression.

• Syntax

  regex_select(value, r"regular expression", mi=None, gi=None)

• Parameters

  Parameter Name	Parameter Type	Required	Description
  value	any	Yes	The value to match.
  regular expression	String	Yes	The regular expression for matching.
  mi	int	No	The index of the match to return. The default value is None or 0, which returns the first match.
  gi	int	No	The index of the capturing group to return. The default value is None or 0, which returns the first group.

• Response

  Returns the matched value.

• Examples

  • Example 1: Extract the first value from the str field that matches the regular expression.

    • Raw log

      str: iZbp1a65x3r1vhpe94fi2qZ

    • Transformation rule

      e_set("regex", regex_select(v("str"), r"\d+"))
      e_set("regex2", regex_select(v("str"), r"\d+", mi=None))
      e_set("regex3", regex_select(v("str"), r"\d+", mi=0))

    • Result

      regex:1
      regex2:1
      regex3:1
      str:iZbp1a65x3r1vhpe94fi2qZ

  • Example 2: Extract the first and second values from the str field that match the regular expression.

    • Raw log

      str: abc123 xyz456

    • Transformation rule

      # Extract the first value from the str field that matches the regular expression.
      e_set("regex", regex_select(v("str"), r"\d+"))
      # Extract the second value from the str field that matches the regular expression.
      e_set("regex2", regex_select(v("str"), r"\d+", mi=1))

    • Result

      regex:   123
      regex2:  456
      str: abc123 xyz456

  • Example 3

    • Raw log

      str: abc123 xyz456

    • Transformation rule

      # Extract the value of the first group from the first expression in the str field that matches the regular expression.
      e_set("regex", regex_select(v("str"),r"[a-z]+(\d+)",gi=0))
      # Extract the value of the first group from the second expression in the str field that matches the regular expression.
      e_set("regex2", regex_select(v("str"),r"[a-z]+(\d+)",mi=1,gi=0))
      # Extract the value of the first group from the first expression in the str field that matches the regular expression.
      e_set("regex3", regex_select(v("str"),r"([a-z]+)(\d+)",gi=0))
      # Extract the value of the second group from the first expression in the str field that matches the regular expression.
      e_set("regex4", regex_select(v("str"),r"([a-z]+)(\d+)",gi=1))

    • Result

      str: abc123 xyz456
      regex:   123
      regex2:  456
      regex3:  abc
      regex4:  123

Returns an array of all values that match a regular expression.

• Syntax

  regex_findall(value, r"regular expression")

• Parameters

  Parameter Name	Parameter Type	Required	Description
  value	any	Yes	The value to match.
  regular expression	String	Yes	The regular expression.

• Response

  Returns a list of all matching values.

• Examples

  Extract all numbers from the str field:

  • Raw log

    str: iZbp1a65x3r1vhpe94fi2qZ

  • Transformation rule

    e_set("regex_findall", regex_findall(v("str"),r"\d+"))

  • Result

    str: iZbp1a65x3r1vhpe94fi2qZ
    regex_findall:  ["1", "65", "3", "1", "94", "2"]

Checks whether a value matches a regular expression.

• Syntax

  regex_match(value, r"regular expression", full=False)

• Parameters

  Parameter Name	Parameter type	Required	Description
  value	any	Yes	The value to match.
  regular expression	string	Yes	The regular expression.
  full	Bool	No	Specifies whether to require a full match. The default value is False.

• Response

  Returns true or false indicating whether the value matches.

• Examples

  Check whether the str field contains numbers:

  • Raw log

    str: iZbp1a65x3r1vhpe94fi2qZ

  • Transformation rule

    # Check whether the str field contains numbers.
    e_set("regex_match", regex_match(v("str"),r"\d+"))
    # Check whether the str field consists of only numbers.
    e_set("regex_match2", regex_match(v("str"),r"\d+",full=True))

  • Result

    str: iZbp1a65x3r1vhpe94fi2qZ
    regex_match:  true
    regex_match2:  false

Replaces specified characters in a string based on a regular expression.

• Syntax

  regex_replace(value, r"regular expression", replace="", count=0)

• Parameters

  Parameter name	Parameter Type	Required	Description
  value	any	Yes	The value to be replaced.
  regular expression	string	Yes	The regular expression.
  replace	string	No	The replacement string. The default value is an empty string, which deletes the matched characters. Regular expressions are supported. For example, r"\1****\2" specifies that the replacement string uses capturing group references. \1 represents the first group. \2 represents the second group.
  count	Number	No	The number of replacements. The default value is 0, which replaces all matches.

• Response

  The string after replacement.

• Examples

  • Example 1: Replace all numbers in the str field with 13.

    • Raw log

      str: iZbp1a65x3r1vhpe94fi2qZ
      replace: 13

    • Transformation rule

      e_set("regex_replace", regex_replace(v("str"),r"\d+",v("replace")))

    • Result

      str: iZbp1a65x3r1vhpe94fi2qZ
      replace: 13
      regex_replace:  iZbp13a13x13r13vhpe13fi13qZ

  • Example 2: Mask the middle four digits of a mobile phone number.

    • Raw log

      iphone: 13900001234

    • Transformation rule

      e_set(
          "sec_iphone",
          regex_replace(v("iphone"), r"(\d{0,3})\d{4}(\d{4})", replace=r"\1****\2"),
      )

      Note

      • replace=r"\1****\2" indicates that the replacement string is formatted as r"\1****\2".

      • \1 represents the first group, which is (\d{0,3}).

      • \2 represents the second group, which is (\d{4}).

    • Result

      iphone: 13900001234
      sec_iphone: 139****1234

Splits a string into an array of strings.

• Syntax

  regex_split(value, r"regular expression", maxsplit=0)

• Parameters

  Parameter Name	Parameter type	Required	Description
  value	any	Yes	The value to split.
  regular expression	string	Yes	The regular expression.
  maxsplit	int	No	The maximum number of splits. The default value is 0, which splits the string at all matches. A value of 1 splits only at the first match.

• Response

  An array of the resulting substrings.

• Examples

  Split the str field by numbers:

  • Raw log

    str: iZbp1a65x3r1vhpe94fi2qZ

  • Transformation rule

    e_set("regex_split", regex_split(v("str"),r"\d+"))

  • Result

    str: iZbp1a65x3r1vhpe94fi2qZ
    regex_split:  ["iZbp", "a", "x", "r", "vhpe", "fi", "qZ"]