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

/
/
mxg

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""" ^.*((?<req_method>GET|POST|PUT|DELETE|CONNECT|OPTIONS|HEAD[^ ]\w+)\s*(?<req_path>[^ ][-._?=%&\/[:alnum:]]*)\s*(?<req_protocol>[^ ][.\/\dHTFSP]+){0,1})|(\s*(status:\s*(?<req_status>[^ ]\d+))\s*(len:\ (?<req_len>[^ ]\d+)){0,1}\s*(time:\s*(?<req_time>[^ ][.\d]+)){0,1}\s*(microversion:\s*(?<req_mver>[^ ][.\d]+)){0,1}){0,1}$ """ test_str = ("\n" "# suse\n\n" "2017-08-14T12:25:56+00:00 d2c-76-8a-ac-64-50 nova-api: 0.3074s 10.60.2.84 GET /latest/user-data None:None 200 [Python-httplib2/0.9.2 (gzip)] text/plain text/plain\n" "2017-08-14T12:25:56+00:00 d2c-76-8a-ac-64-50 nova-api: 10.3.4.171,10.60.2.84 \"GET /latest/user-data HTTP/1.1\" status: 200 len: 374 time: 0.0037200\n" "2017-08-14T12:25:56+00:00 d2c-76-8a-ac-64-6e nova-api: 0.6576s 10.60.2.84 GET /latest/user-data None:None 200 [Python-httplib2/0.9.2 (gzip)] text/plain text/plain\n" "2017-08-14T12:25:56+00:00 d2c-76-8a-ac-64-6e nova-api: 10.3.4.171,10.60.2.84 \"GET /latest/user-data HTTP/1.1\" status: 200 len: 374 time: 0.0074589\n" "2017-08-14T12:25:56+00:00 d2c-76-8a-ac-65-68 nova-api: 0.2532s 10.60.2.84 GET /latest/user-data None:None 200 [Python-httplib2/0.9.2 (gzip)] text/plain text/plain\n" "2017-08-14T12:25:56+00:00 d2c-76-8a-ac-65-68 nova-api: 10.3.4.172,10.60.2.84 \"GET /latest/user-data HTTP/1.1\" status: 200 len: 374 time: 0.0029602\n" "kkk\n" "2017-08-14T12:25:56+00:00 d2c-76-8a-ac-64-50 nova-api: 0.3033s 10.60.2.84 GET /latest/meta-data/public-keys/0/openssh-key None:None 200 [Python-httplib2/0.9.2 (gzip)] text/plain text/plain\n" "2017-08-14T12:25:56+00:00 d2c-76-8a-ac-64-50 nova-api: 0.3033s 10.60.2.84 GET /latest/meta-data/public-keys/0/openssh-key None:None 200 [Python-httplib2/0.9.2 (gzip)] text/plain text/plain\n" "kkkk\n" "2017-08-14T12:25:56+00:00 d2c-76-8a-ac-64-50 nova-api: 10.3.4.85,10.60.2.84 \"GET /latest/meta-data/public-keys/0/openssh-key HTTP/1.1\" status: 200 len: 881 time: 0.0036240\n\n\n" "# mirantis\n\n\n" "==> ./nova-api.log <==\n" "2017-09-27 07:54:18.201 5490 INFO nova.metadata.wsgi.server [-] 172.17.45.11 \"OPTIONS / HTTP/1.0\" status: 200 len: 234 time: 0.0007069\n" "2017-09-27 07:54:19.852 5490 INFO nova.metadata.wsgi.server [-] 172.17.45.13 \"OPTIONS / HTTP/1.0\" status: 200 len: 234 time: 0.0010118\n" "2017-09-27 07:54:20.243 5474 INFO nova.osapi_compute.wsgi.server [req-88f8732a-4a36-42b0-9e00-6cf0aca395da 6335aa7b2294478d867b25f3b1b0c77c 26e4dd19485249608ee3685f254f3909 - default default] 172.17.48.232,172.17.45.13 \"GET /v2.1/26e4dd19485249608ee3685f254f3909/servers/detail?name=%5Ectl03%5C.kkk-deploy-heat-k8s-ha-calico-161%5C.kkk-mk%5C.kk%24&status=ACTIVE HTTP/1.1\" status: 200 len: 3239 time: 0.8562572\n" "2017-09-27 07:54:21.291 5474 INFO nova.osapi_compute.wsgi.server [-] 172.17.45.12 \"GET / HTTP/1.1\" status: 200 len: 482 time: 0.0020030\n" "2017-09-27 07:54:22.398 5474 INFO nova.osapi_compute.wsgi.server [-] 172.17.45.12 \"OPTIONS / HTTP/1.0\" status: 200 len: 501 time: 0.0011830\n" "2017-09-27 07:54:23.323 5484 INFO nova.metadata.wsgi.server [-] 172.17.45.12 \"OPTIONS / HTTP/1.0\" status: 200 len: 234 time: 0.0010719\n" "2017-09-27 07:54:25.713 5476 INFO nova.osapi_compute.wsgi.server [-] 172.17.45.13 \"OPTIONS / HTTP/1.0\" status: 200 len: 501 time: 0.0013640\n" "2017-09-27 07:54:27.261 5473 INFO nova.osapi_compute.wsgi.server [-] 172.17.45.11 \"OPTIONS / HTTP/1.0\" status: 200 len: 501 time: 0.0017979\n" "2017-09-27 07:54:27.594 5471 INFO nova.osapi_compute.wsgi.server [req-7ba73d12-c18a-4c59-9b35-95be06ea45a2 6335aa7b2294478d867b25f3b1b0c77c 26e4dd19485249608ee3685f254f3909 - default default] 172.17.48.231,172.17.45.13 \"GET /v2.1/26e4dd19485249608ee3685f254f3909/servers/detail?name=%5Ectl01%5C.kkkk-deploy-heat-k8s-ha-calico-161%5C.kk-mk%5C.kk%24&status=ACTIVE HTTP/1.1\" status: 200 len: 3239 time: 0.8599730\n" "2017-09-27 07:54:27.885 5486 INFO nova.metadata.wsgi.server [-] 172.17.45.11 \"OPTIONS / HTTP/1.0\" status: 200 len: 234 time: 0.0009840\n\n" "==> ./nova-cert.log <==\n\n" "==> ./nova-conductor.log <==\n\n" " File \"/usr/lib/python2.7/dist-packages/nova/scheduler/manager.py\", line 98, in select_destinations\n" " dests = self.driver.select_destinations(ctxt, spec_obj)\n\n" " File \"/usr/lib/python2.7/dist-packages/nova/scheduler/filter_scheduler.py\", line 79, in select_destinations\n" " raise exception.NoValidHost(reason=reason)\n\n" "NoValidHost: No valid host was found. There are not enough hosts available.\n\n" "2017-09-27 07:15:40.310 21389 WARNING nova.scheduler.utils [req-c8be6870-ab24-4080-80e9-864130bf382a 38faea7239db49aca33e866451271d47 5e6af85573c5434190c59cbd2caa0558 - - -] [instance: 5a2e94e6-2dfa-4e15-b60c-d0819b456a3c] Setting instance to ERROR state.\n\n" "==> ./nova-consoleauth.log <==\n\n" "==> ./nova-manage.log <==\n\n" "==> ./nova-novncproxy.log <==\n\n" "==> ./nova-placement-api.log <==\n" "2017-09-27 07:54:29.137 19423 INFO nova.api.openstack.placement.requestlog [req-b5049cf9-9453-4990-942d-1420bc91b33c 78061f04af2741309c970a4c360d1a27 2e6cdfb7870c43e8b5ed0d216430c0f2 - default default] 172.17.45.13 \"GET /allocations/18fec513-0a0e-4427-9c9f-fecac9f2b3dd\" status: 200 len: 139 microversion: 1.0\n" "2017-09-27 07:54:29.255 19420 INFO nova.api.openstack.placement.requestlog [req-36804863-094b-415d-a7b4-ca60bdcba3cb 78061f04af2741309c970a4c360d1a27 2e6cdfb7870c43e8b5ed0d216430c0f2 - default default] 172.17.45.13 \"GET /allocations/47ca5912-2f84-4619-8ea3-b13bba51e3ab\" status: 200 len: 138 microversion: 1.0\n" "2017-09-27 07:54:29.309 19423 INFO nova.api.openstack.placement.requestlog [req-f144ce6c-0e5c-40e1-8dfa-9665a22ce61e 78061f04af2741309c970a4c360d1a27 2e6cdfb7870c43e8b5ed0d216430c0f2 - default default] 172.17.45.13 \"GET /allocations/66fbf2d6-9081-4124-a0ab-353373ef65c5\" status: 200 len: 140 microversion: 1.0\n" "2017-09-27 07:54:29.379 19422 INFO nova.api.openstack.placement.requestlog [req-8fa4cb3e-0aa2-4d8c-ba60-9e53399930d2 78061f04af2741309c970a4c360d1a27 2e6cdfb7870c43e8b5ed0d216430c0f2 - default default] 172.17.45.13 \"GET /allocations/1392ea8e-c15d-4429-a8f6-028486c62069\" status: 200 len: 139 microversion: 1.0\n" "2017-09-27 07:54:29.461 19424 INFO nova.api.openstack.placement.requestlog [req-91d23b20-2266-4134-8ee8-7c92f0b95597 78061f04af2741309c970a4c360d1a27 2e6cdfb7870c43e8b5ed0d216430c0f2 - default default] 172.17.45.13 \"GET /allocations/d07be933-717b-4c6a-bb87-04eff357401f\" status: 200 len: 139 microversion: 1.0\n" "2017-09-27 07:54:29.554 19421 INFO nova.api.openstack.placement.requestlog [req-abade4bf-ca08-4057-b5ab-d87f131d332d 78061f04af2741309c970a4c360d1a27 2e6cdfb7870c43e8b5ed0d216430c0f2 - default default] 172.17.45.13 \"GET /allocations/be4a8fdb-e752-426c-b289-e3d348c17c32\" status: 200 len: 138 microversion: 1.0\n" "2017-09-27 07:54:29.657 19420 INFO nova.api.openstack.placement.requestlog [req-323f54dc-ac28-4132-8d0d-bcec02adbb46 78061f04af2741309c970a4c360d1a27 2e6cdfb7870c43e8b5ed0d216430c0f2 - default default] 172.17.45.13 \"GET /allocations/059795b7-1fb1-471d-8c1d-155796829654\" status: 200 len: 140 microversion: 1.0\n" "2017-09-27 07:54:29.788 19424 INFO nova.api.openstack.placement.requestlog [req-49a4f749-b4c3-4bc1-8ff8-cda84a76c5d6 78061f04af2741309c970a4c360d1a27 2e6cdfb7870c43e8b5ed0d216430c0f2 - default default] 172.17.45.13 \"GET /allocations/2bda36f7-554b-401d-a164-d54c4dbf8541\" status: 200 len: 138 microversion: 1.0\n" "2017-09-27 07:54:29.873 19423 INFO nova.api.openstack.placement.requestlog [req-fb403cec-b321-4359-8080-60aac7b45a89 78061f04af2741309c970a4c360d1a27 2e6cdfb7870c43e8b5ed0d216430c0f2 - default default] 172.17.45.13 \"GET /allocations/d6dd2de7-be41-45b3-baba-5040a124ce62\" status: 200 len: 138 microversion: 1.0\n" "2017-09-27 07:54:29.979 19420 INFO nova.api.openstack.placement.requestlog [req-63204536-50d7-4d22-bbca-fa7c487d50cb 78061f04af2741309c970a4c360d1a27 2e6cdfb7870c43e8b5ed0d216430c0f2 - default default] 172.17.45.13 \"GET /allocations/d28b8bcc-c615-47c2-b1a8-bf2442822c6c\" status: 200 len: 138 microversion: 1.0\n\n" "==> ./nova-scheduler.log <==\n" "2017-09-27 07:53:42.368 21466 INFO nova.scheduler.host_manager [req-2d01b887-5204-420f-88ea-418c64709a69 - - - - -] Successfully synced instances from host 'cmp010'.\n" "2017-09-27 07:53:44.275 21466 INFO nova.scheduler.host_manager [req-76046843-1bc5-4beb-9880-6757eb786d42 - - - - -] Successfully synced instances from host 'cmp020'.\n" "2017-09-27 07:54:00.299 21466 INFO nova.scheduler.host_manager [req-deb8cc20-9764-401f-8247-8afb67dfd203 - - - - -] Successfully synced instances from host 'cmp017'.\n" "2017-09-27 07:54:07.404 21466 INFO nova.scheduler.host_manager [req-80bf05f3-6d17-4e23-9dda-b26c564f54c6 - - - - -] Successfully synced instances from host 'cmp022'.\n" "2017-09-27 07:54:12.376 21466 INFO nova.scheduler.host_manager [req-13ba5740-05c4-4afc-b79e-f6400ce0fa49 - - - - -] Successfully synced instances from host 'cmp016'.\n" "2017-09-27 07:54:15.779 21466 INFO nova.scheduler.host_manager [req-20de93ad-3f06-47a0-966e-0edc038f67b7 - - - - -] Successfully synced instances from host 'cmp011'.\n" "2017-09-27 07:54:22.353 21466 INFO nova.scheduler.host_manager [req-c6526914-d9ee-460c-b837-69779acc93b8 - - - - -] Successfully synced instances from host 'cmp005'.\n" "2017-09-27 07:54:25.333 21466 INFO nova.scheduler.host_manager [req-b1cfabef-1f65-44a9-bfce-dd31d3aac46b - - - - -] Successfully synced instances from host 'cmp004'.\n" "2017-09-27 07:54:27.122 21466 INFO nova.scheduler.host_manager [req-aff27712-931a-4293-8ea2-cb17557c96d5 - - - - -] Successfully synced instances from host 'cmp003'.\n" "2017-09-27 07:54:29.753 21466 INFO nova.scheduler.host_manager [req-f61a4b58-7f3a-4c82-a214-c3ba8e722de5 - - - - -] Successfully synced instances from host 'cmp031'.\n") matches = re.finditer(regex, test_str, re.MULTILINE | re.VERBOSE) 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