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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"^<.{20}(?<hlt_env>.+?) esc-logs", flags=re.MULTILINE) test_str = ("<13>Jan. 05 23:59:59 HLT-DM01 esc-logs[-]: {\"timestamp\":\"2021-01-05T23:59:59.889Z\",\"id\":\"98cf03ff-8dba-4b84-990c-4f026a2fa942\",\"tenant_name\":\"draco-910\",\"pks_uuid\":\"934ac265-9e3c-4a0d-8798-109b15876e4e\",\"hlt-cluster\":[\"api.prod-s-k8s.draco-910.sccloudres.net\",\"api.prod-m-k8s.draco-910.sccloudres.net\"],\"log_type\":\"AUDIT\",\"log_entry\":\"<14>1 2021-01-05T23:59:59.889967Z 682e85b4-e773-4ef7-9c8b-193034f2eca9.master.pks-934ac265-9e3c-4a0d-8798-109b15876e4e.service-instance-934ac265-9e3c-4a0d-8798-109b15876e4e.bosh kube-apiserver rs2 - [instance@47450 director=\\\"\\\" deployment=\\\"service-instance_934ac265-9e3c-4a0d-8798-109b15876e4e\\\" group=\\\"master\\\" az=\\\"WL-BEW-Prd-01\\\" id=\\\"682e85b4-e773-4ef7-9c8b-193034f2eca9\\\"] {\\\"kind\\\":\\\"Event\\\",\\\"apiVersion\\\":\\\"audit.k8s.io/v1\\\",\\\"level\\\":\\\"Request\\\",\\\"auditID\\\":\\\"b3b53fd5-4d9d-4626-90bb-ac0de8234585\\\",\\\"stage\\\":\\\"ResponseComplete\\\",\\\"requestURI\\\":\\\"/api/v1/nodes/321c1ee3-21ba-43e1-8c5f-4b73a30d111c/proxy/metrics\\\",\\\"verb\\\":\\\"get\\\",\\\"user\\\":{\\\"username\\\":\\\"system:serviceaccount:monitoring:prometheus-monitoring\\\",\\\"uid\\\":\\\"abb07484-47d5-462c-b460-682dd0c0768d\\\",\\\"groups\\\":[\\\"system:serviceaccounts\\\",\\\"system:serviceaccounts:monitoring\\\",\\\"system:authenticated\\\"]},\\\"sourceIPs\\\":[\\\"11.32.19.6\\\"],\\\"userAgent\\\":\\\"Prometheus/2.19.3\\\",\\\"objectRef\\\":{\\\"resource\\\":\\\"nodes\\\",\\\"name\\\":\\\"321c1ee3-21ba-43e1-8c5f-4b73a30d111c\\\",\\\"apiVersion\\\":\\\"v1\\\",\\\"subresource\\\":\\\"proxy\\\"},\\\"responseStatus\\\":{\\\"metadata\\\":{},\\\"code\\\":200},\\\"requestReceivedTimestamp\\\":\\\"2021-01-05T23:59:59.434872Z\\\",\\\"stageTimestamp\\\":\\\"2021-01-05T23:59:59.456258Z\\\",\\\"annotations\\\":{\\\"authorization.k8s.io/decision\\\":\\\"allow\\\",\\\"authorization.k8s.io/reason\\\":\\\"RBAC: allowed by ClusterRoleBinding \\\\\\\"prometheus-monitoring\\\\\\\" of ClusterRole \\\\\\\"prometheus-monitoring\\\\\\\" to ServiceAccount \\\\\\\"prometheus-monitoring/monitoring\\\\\\\"\\\"}}\",\"version\":\"1.0\",\"@version\":\"1\",\"cloud_service_name\":\"KUBERNETES\",\"@timestamp\":\"2021-01-05T23:59:59.889Z\"}\n") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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