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"^t=(?<longtime>[^ ]+)\s*lvl=(?<loglevel>[^ ]+)\s*msg=(?<msg>(?:\"[^\"]+\"|[^ ]+))\s*logger=(?<logger>[^ ]+)\s*(?:addresses=(?<email>(?:\"\[[^\"]+\]\"|[^ ]+)))?(?:userId=(?<userID>[^ ]+))?\s*(?:orgId=(?<orgID>[^ ]+))?\s*(?:uname=(?<uname>[^ ]+|[??]*))?\s*(?:method=(?<method>[^ ]+))?\s*(?:path=(?<path>(?:\"[^\"]+\"|[^ ]+)))?\s*(?:ruleId=(?<ruleID>[^ ]+))?\s*(?:name=(?<name>(?:\"[^\"]+\"|[^ ]+)))?\s*(?:error=(?<error>(?:\"[^\"]+\"|[^ ]+)))?\s*(?:changing state to=(?<ChStateTo>[^ ]+))?\s*(?:status=(?<status>[^ ]+))?\s*(?:remote_addr=(?<remote_addr>[^ ]+))?\s*(?:time_ms=(?<time_ms>[^ ]+))?\s*(?:size=(?<size>[^ ]+))?\s*(?:referer=(?<referer>(?:\"[^\"]+\"|[^ ]+)|[??]*))?\s*(?:alertId=(?<alertID>[^ ]+))?\s*(?:newState=(?<NewState>[^ ]+))?\s*(?:prev state=(?<prevState>[^ ]+))?\s*(?:url=(?<url>[^ ]+))?$" test_str = ("t=2019-07-30T07:22:35+0300 lvl=eror msg=\"Alert Rule Result Error\" logger=alerting.evalContext ruleId=22 name=\"Выдача сломалась!\" error=\"Alert execution exceeded the timeout\" changing state to=alerting\n" "t=2019-07-30T07:22:39+0300 lvl=info msg=\"New state change\" logger=alerting.resultHandler alertId=48 newState=alerting prev state=ok\n" "t=2019-07-30T07:22:39+0300 lvl=info msg=\"uploaded screenshot of alert to external image store\" logger=alerting.notifier url=http://10.233.60.59:8080/grafana/TylgxQWG4Aiq6kmlSrM4.png\n" "t=2019-07-30T07:22:39+0300 lvl=info msg=\"uploaded screenshot of alert to external image store\" logger=alerting.notifier url=http://10.233.60.59:8080/grafana/lsfc738fTMkR034AZM2j.png\n" "t=2019-07-30T07:22:39+0300 lvl=info msg=\"Sending webhook\" logger=alerting.notifier.webhook\n" "t=2019-07-30T07:22:39+0300 lvl=info msg=\"Sending webhook\" logger=alerting.notifier.webhook\n" "t=2019-07-30T07:22:40+0300 lvl=eror msg=\"Alert Rule Result Error\" logger=alerting.evalContext ruleId=89 name=Вход.Формы.Статусы error=\"Alert execution exceeded the timeout\" changing state to=alerting\n" "t=2019-07-30T07:22:40+0300 lvl=info msg=\"New state change\" logger=alerting.resultHandler alertId=89 newState=alerting prev state=ok\n" "t=2019-07-30T07:22:40+0300 lvl=eror msg=\"Alert Rule Result Error\" logger=alerting.evalContext ruleId=88 name=\"Exception State alert\" error=\"Alert execution exceeded the timeout\" changing state to=alerting\n" "t=2019-07-30T07:22:40+0300 lvl=info msg=\"uploaded screenshot of alert to external image store\" logger=alerting.notifier url=http://10.233.60.59:8080/grafana/tQeLMXFNBU6y6USKOe5E.png\n" "t=2019-07-30T07:22:40+0300 lvl=info msg=\"Sending webhook\" logger=alerting.notifier.webhook\n" "t=2019-07-30T07:22:42+0300 lvl=eror msg=\"Alert Rule Result Error\" logger=alerting.evalContext ruleId=21 name=\"HermesApiErrors alert\" error=\"Alert execution exceeded the timeout\" changing state to=alerting\n" "t=2019-07-30T07:22:42+0300 lvl=eror msg=\"Alert Rule Result Error\" logger=alerting.evalContext ruleId=26 name=\"Генерация отчетов на Jasper alert\" error=\"Alert execution exceeded the timeout\" changing state to=keep_state\n" "t=2019-07-30T07:22:45+0300 lvl=eror msg=\"Alert Rule Result Error\" logger=alerting.evalContext ruleId=32 name=\"СРВО. Фоновые задачи\" error=\"Alert execution exceeded the timeout\" changing state to=alerting\n" "t=2019-07-30T07:22:45+0300 lvl=info msg=\"New state change\" logger=alerting.resultHandler alertId=32 newState=alerting prev state=ok\n" "t=2019-07-30T07:22:45+0300 lvl=info msg=\"uploaded screenshot of alert to external image store\" logger=alerting.notifier url=http://10.233.60.59:8080/grafana/yZzqi4QmGCvSbYraq3UC.png\n" "t=2019-07-30T07:22:45+0300 lvl=info msg=\"Sending webhook\" logger=alerting.notifier.webhook\n" "t=2019-07-30T07:22:45+0300 lvl=info msg=\"Sending alert notification to\" logger=alerting.notifier.email addresses=\"[Andrey.Kudashkin@russianpost.ru Arkhipov.Alexander@russianpost.ru szhogin@luxoft.com OPodus@luxoft.com]\"\n" "t=2019-07-30T07:22:47+0300 lvl=eror msg=\"Alert Rule Result Error\" logger=alerting.evalContext ruleId=135 name=\"pochtaid-sso alert\" error=\"Alert execution exceeded the timeout\" changing state to=alerting\n" "t=2019-07-30T07:22:47+0300 lvl=info msg=\"New state change\" logger=alerting.resultHandler alertId=135 newState=alerting prev state=ok\n" "t=2019-07-30T07:22:47+0300 lvl=eror msg=\"Alert Rule Result Error\" logger=alerting.evalContext ruleId=90 name=\"Профиль. Статус\" error=\"Alert execution exceeded the timeout\" changing state to=alerting\n" "t=2019-07-30T07:22:47+0300 lvl=info msg=\"New state change\" logger=alerting.resultHandler alertId=90 newState=alerting prev state=ok\n" "t=2019-07-30T07:22:47+0300 lvl=eror msg=\"Alert Rule Result Error\" logger=alerting.evalContext ruleId=136 name=\"Normalization alert\" error=\"Alert execution exceeded the timeout\" changing state to=alerting\n" "t=2019-07-30T07:22:47+0300 lvl=info msg=\"New state change\" logger=alerting.resultHandler alertId=136 newState=alerting prev state=ok\n" "t=2019-07-30T07:22:47+0300 lvl=info msg=\"uploaded screenshot of alert to external image store\" logger=alerting.notifier url=http://10.233.60.59:8080/grafana/qXR85haxAmRX5g1vqrmT.png\n" "t=2019-07-30T07:22:47+0300 lvl=info msg=\"uploaded screenshot of alert to external image store\" logger=alerting.notifier url=http://10.233.60.59:8080/grafana/dOfYePDh7n3oreQhaRCR.png\n" "t=2019-07-30T07:22:47+0300 lvl=info msg=\"Sending webhook\" logger=alerting.notifier.webhook\n" "t=2019-07-30T07:22:47+0300 lvl=info msg=\"uploaded screenshot of alert to external image store\" logger=alerting.notifier url=http://10.233.60.59:8080/grafana/4eIoX3qCRuF16DoXNbRU.png\n") 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