Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gm

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"^.*?]\s(?<severity>\w+)\s+(?<group>[^\[]+)\[(?<action>\w+)\,\s+.*?name=(?<login>\w+)\,\s+usid=(?<recipient>\w+)\,\s+addr=(?<sip>.*?)\,\s+prot=(?<session>.*?)\]\,\s+db=(?<status>.*?)\]$" test_str = ("10 23 2018 09:23:59 1.1.1.1 <LOC2:WARN> Oct 23 09:24:00 2018-10-23 09:24:00,076 [Thread-0] WARN EventLHost1d- UserSessNotification[STOP_TRANS, user=[name=admin, usid=72422, addr=127.0.0.1, prot=1], db=DB_RUNNING]\n\n" "10 22 2018 17:07:48 1.1.4.1 <LOC2:WARN> Oct 22 17:08:00 2018-10-23 03: 08:00,393 [Thread-0] WARN EventLHost1d- AuditNotification[logno=103, user=admin, usid=0, msg=\"Logged in over ssh using externalauth, member of groups: admin,auditor,manage-appliance,manage-pki,manage-policy\"]\n\n" "10 19 2018 12:36:18 1.1.1.1 <LOC2:WARN> Oct 19 12:36:19 2018-10-19 12: 36:19,112 [Thread-0] WARN EventLHost1d- UserSessNotification[STOP, user=[name=admin, usid=27572, addr=127.0.0.1, prot=1], db=DB_NONE]\n\n" "10 22 2018 09:36:11 1.1.4.1 <LOC2:WARN> Oct 22 09:36:22 2018-10-22 19: 36:22,691 [Thread-0] WARN EventLHost1d- AuditNotification[logno=107, user=admin, usid=32891, msg=\"Logged out from maapi ctx=webui (closed)\"]\n\n" "10 24 2018 09:31:54 1.1.1.1 <LOC2:ALRT> Oct 24 09:31:55 SSLCDMX Health monitoring: PROBLEM - SSLCDMX Metric: Load Utilization WARNING: Memory load is at 67.46%. - Capacity util=30.31%\n\n" "10 22 2018 19:30:13 1.1.3.1 <LOC2:WARN> Oct 22 17:31:38 2018-10-22 17: 31:38,947 [Thread-0] WARN EventLHost1d- AuditNotification[logno=105, user=admin, usid=73051, msg=\"assigned to groups: manage-policy,manage-pki,manage-appliance,auditor,admin\"]\n\n" "10 23 2018 22:46:23 1.2.3.1 <LOC2:ALRT> Oct 24 01:45:01 SSLREYNOSA root: Health Monitoring (cron): Trimmed event history to 30 days.\n\n" "10 23 2018 10:04:05 1.1.1.1 <LOC2:WARN> Oct 23 10:04:06 2018-10-23 10: 04:06,531 [Thread-0] WARN EventLHost1d- AuditNotification[logno=105, user=Host2ez, usid=72793, msg=\"assigned to groups: manage-pki\"]") matches = re.finditer(regex, test_str, re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Python, please visit: https://docs.python.org/3/library/re.html