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

Substitution

Processing...

Code Generator

Language

Generated Code

$re = '~^ [0-9]{4}/[0-9]{2}/[0-9]{2} [0-9]{2}:[0-9]{2}:[0-9]{2} \[\w+\] [0-9]+#[0-9]+:( \*[0-9]+)? (.*?)(( while( \\\\w+)+)?|, client: [^,]*|, server: [^,]*|, request: \"\w+ [^\"]* HTTP/[^\"]+\"|, host: \"[^\"]*\"|, upstream: \"[^\"]*\"|, referrer: \"[^\"]*\"|, subrequest: \"[^\"]*\"|, ctx: \'[^\']*\')*$~m'; $str = ' 2019/07/05 08:07:42 [info] 12759#12759: *32118 [lua] logging.lua:60: log(): req(f6c4b9e6-9efb-11e9-b199-005056a7ce13): Public inbound request (participant avatar): /rcvideo/v1/bridges/rnd01-t11-ndb01f1741f9416bc12ca506d77/meetings/rnd01-t11-ndb01f1741f9416bc12ca506d77_1562314057547!vi11-1/participants/3a9d_2571/profile-image/584x584?access_token=QU1TMDJQMDFQQVMwMHxBQUFXdm8yZ3hqY2NiZ0NvSXNReTFqT2FvZkFCTVhUNkRKdUNJdHBrazJ4dWJyWFl2akJqeVlUNmVQejJIVHRCRi1DdG5laEVYQnJSbVpXV0FRS3hHRVFwamlILW1haC1Ja1R4YnA4cWgzWlFZLWM0UWkzQm9iYmRWQUNKRnNtZ0NfWTRpeDJnMVFRak5zRkRtaFBWM0dId3dQUTdkZ1dnQU82bjBBM3ZsbWRlSlk4b215dUxjSHowSWR4NjRyR296b1NrTzBUOWduWFNzNUh0QllSQmNkbEl8Q25FdXJBfFlyRUFjVzY0MzdFOWZHeVotWE1Gb1F8QUE&allowSvg=true, client: 10.62.134.38, server: , request: "GET /rcvideo/v1/bridges/rnd01-t11-ndb01f1741f9416bc12ca506d77/meetings/rnd01-t11-ndb01f1741f9416bc12ca506d77_1562314057547!vi11-1/participants/3a9d_2571/profile-image/584x584?access_token=QU1TMDJQMDFQQVMwMHxBQUFXdm8yZ3hqY2NiZ0NvSXNReTFqT2FvZkFCTVhUNkRKdUNJdHBrazJ4dWJyWFl2akJqeVlUNmVQejJIVHRCRi1DdG5laEVYQnJSbVpXV0FRS3hHRVFwamlILW1haC1Ja1R4YnA4cWgzWlFZLWM0UWkzQm9iYmRWQUNKRnNtZ0NfWTRpeDJnMVFRak5zRkRtaFBWM0dId3dQUTdkZ1dnQU82bjBBM3ZsbWRlSlk4b215dUxjSHowSWR4NjRyR296b1NrTzBUOWduWFNzNUh0QllSQmNkbEl8Q25FdXJBfFlyRUFjVzY0MzdFOWZHeVotWE1Gb1F8QUE&allowSvg=true HTTP/1.1", host: "rnd01-t08-pwr01.lab.nordigy.ru", referrer: "https://vi11-1-v.lab.nordigy.ru/conf/on/644926345" 2019/07/05 08:07:42 [debug] 12759#12759: *32118 [lua] logging.lua:60: log(): req(f6c4b9e6-9efb-11e9-b199-005056a7ce13): Headers: RCAccountId: ; RCExtensionId: ; RCAppEndpointId: 4db17762-a1a0-404b-b118-1e8bdec1f900; RCRequestOrigin: Internal; 2019/07/05 08:07:42 [info] 12759#12759: *32118 [lua] logging.lua:60: log(): req(f6c4b9e6-9efb-11e9-b199-005056a7ce13): Making outbound subrequest to RCT/CHS: /rcvideo/v1/intapi/bridges/rnd01-t11-ndb01f1741f9416bc12ca506d77/meetings/rnd01-t11-ndb01f1741f9416bc12ca506d77_1562314057547!vi11-1/participants/3a9d_2571/profile-uri ..., client: 10.62.134.38, server: , request: "GET /rcvideo/v1/bridges/rnd01-t11-ndb01f1741f9416bc12ca506d77/meetings/rnd01-t11-ndb01f1741f9416bc12ca506d77_1562314057547!vi11-1/participants/3a9d_2571/profile-image/584x584?access_token=QU1TMDJQMDFQQVMwMHxBQUFXdm8yZ3hqY2NiZ0NvSXNReTFqT2FvZkFCTVhUNkRKdUNJdHBrazJ4dWJyWFl2akJqeVlUNmVQejJIVHRCRi1DdG5laEVYQnJSbVpXV0FRS3hHRVFwamlILW1haC1Ja1R4YnA4cWgzWlFZLWM0UWkzQm9iYmRWQUNKRnNtZ0NfWTRpeDJnMVFRak5zRkRtaFBWM0dId3dQUTdkZ1dnQU82bjBBM3ZsbWRlSlk4b215dUxjSHowSWR4NjRyR296b1NrTzBUOWduWFNzNUh0QllSQmNkbEl8Q25FdXJBfFlyRUFjVzY0MzdFOWZHeVotWE1Gb1F8QUE&allowSvg=true HTTP/1.1", host: "rnd01-t08-pwr01.lab.nordigy.ru", referrer: "https://vi11-1-v.lab.nordigy.ru/conf/on/644926345" 2019/07/05 08:07:42 [info] 12759#12759: *32118 [lua] logging.lua:60: log(): req(f6c4b9e6-9efb-11e9-b199-005056a7ce13): RCT/CHS: Status: 200 while sending to client, client: 10.62.134.38, server: , request: "GET /rcvideo/v1/bridges/rnd01-t11-ndb01f1741f9416bc12ca506d77/meetings/rnd01-t11-ndb01f1741f9416bc12ca506d77_1562314057547!vi11-1/participants/3a9d_2571/profile-image/584x584?access_token=QU1TMDJQMDFQQVMwMHxBQUFXdm8yZ3hqY2NiZ0NvSXNReTFqT2FvZkFCTVhUNkRKdUNJdHBrazJ4dWJyWFl2akJqeVlUNmVQejJIVHRCRi1DdG5laEVYQnJSbVpXV0FRS3hHRVFwamlILW1haC1Ja1R4YnA4cWgzWlFZLWM0UWkzQm9iYmRWQUNKRnNtZ0NfWTRpeDJnMVFRak5zRkRtaFBWM0dId3dQUTdkZ1dnQU82bjBBM3ZsbWRlSlk4b215dUxjSHowSWR4NjRyR296b1NrTzBUOWduWFNzNUh0QllSQmNkbEl8Q25FdXJBfFlyRUFjVzY0MzdFOWZHeVotWE1Gb1F8QUE&allowSvg=true HTTP/1.1", host: "rnd01-t08-pwr01.lab.nordigy.ru", referrer: "https://vi11-1-v.lab.nordigy.ru/conf/on/644926345" 2019/07/05 08:07:42 [info] 12759#12759: *32118 [lua] logging.lua:60: log(): req(f6c4b9e6-9efb-11e9-b199-005056a7ce13): Internal inbound request: /rcvideo/v1/intapi/uas/profile-image?accountId=&extensionId=&avatarUrl=https%3A%2F%2Fglipdevnet-rndtapams.s3.amazonaws.com%2Fweb%2Fcustomer_files%2F2383884%2Fmodified.jpg%3FExpires%3D2075494478%26AWSAccessKeyId%3DAKIAJO2PPFO3JEGRU4ZQ%26Signature%3DZvjWU0tKo6rLyN1ET2p6zBGQ8bI%253D&displayName=Joseph%20Tribbiani&type=regular&allow_svg=true&size=584x584&request_id=f6c4b9e6-9efb-11e9-b199-005056a7ce13 ..., client: 10.62.134.38, server: , request: "GET /rcvideo/v1/bridges/rnd01-t11-ndb01f1741f9416bc12ca506d77/meetings/rnd01-t11-ndb01f1741f9416bc12ca506d77_1562314057547!vi11-1/participants/3a9d_2571/profile-image/584x584?access_token=QU1TMDJQMDFQQVMwMHxBQUFXdm8yZ3hqY2NiZ0NvSXNReTFqT2FvZkFCTVhUNkRKdUNJdHBrazJ4dWJyWFl2akJqeVlUNmVQejJIVHRCRi1DdG5laEVYQnJSbVpXV0FRS3hHRVFwamlILW1haC1Ja1R4YnA4cWgzWlFZLWM0UWkzQm9iYmRWQUNKRnNtZ0NfWTRpeDJnMVFRak5zRkRtaFBWM0dId3dQUTdkZ1dnQU82bjBBM3ZsbWRlSlk4b215dUxjSHowSWR4NjRyR296b1NrTzBUOWduWFNzNUh0QllSQmNkbEl8Q25FdXJBfFlyRUFjVzY0MzdFOWZHeVotWE1Gb1F8QUE&allowSvg=true HTTP/1.1", host: "rnd01-t08-pwr01.lab.nordigy.ru", referrer: "https://vi11-1-v.lab.nordigy.ru/conf/on/644926345" 2019/07/05 08:07:42 [debug] 12759#12759: *32118 [lua] logging.lua:60: log(): req(f6c4b9e6-9efb-11e9-b199-005056a7ce13): Redirecting to /avatar/from-url (fallbacks: /avatar/from-nodejs;/errors/cannot-generate)... 2019/07/05 08:07:42 [debug] 12759#12759: *32118 [lua] set_by_lua:12: req(f6c4b9e6-9efb-11e9-b199-005056a7ce13): Fallback information: arg_fallback: "%2Favatar%2Ffrom-nodejs%3B%2Ferrors%2Fcannot-generate"; fallback_location: "/avatar/from-nodejs"; fallback_url: "/avatar/from-nodejs?fallback=%2Ferrors%2Fcannot%2Dgenerate&size=584x584&extension_id=&avatar_url=https%3A%2F%2Fglipdevnet-rndtapams.s3.amazonaws.com%2Fweb%2Fcustomer_files%2F2383884%2Fmodified.jpg%3FExpires%3D2075494478%26AWSAccessKeyId%3DAKIAJO2PPFO3JEGRU4ZQ%26Signature%3DZvjWU0tKo6rLyN1ET2p6zBGQ8bI%253D&request_id=f6c4b9e6-9efb-11e9-b199-005056a7ce13&account_id=&allow_svg=true&type=regular&display_name=Joseph%20Tribbiani&without_user_pic=false"; args_reduced_fallback: "size=584x584&extension_id=&avatar_url=https%3A%2F%2Fglipdevnet-rndtapams.s3.amazonaws.com%2Fweb%2Fcustomer_files%2F2383884%2Fmodified.jpg%3FExpires%3D2075494478%26AWSAccessKeyId%3DAKIAJO2PPFO3JEGRU4ZQ%26Signature%3DZvjWU0tKo6rLyN1ET2p6zBGQ8bI%253D&request_id=f6c4b9e6-9efb-11e9-b199-005056a7ce13&account_id=&allow_svg=true&type=regular&display_name=Joseph%20Tribbiani&without_user_pic=false"; args: "fallback=%2Favatar%2Ffrom-nodejs%3B%2Ferrors%2Fcannot-generate&size=584x584&extension_id=&avatar_url=https%3A%2F%2Fglipdevnet-rndtapams.s3.amazonaws.com%2Fweb%2Fcustomer_files%2F2383884%2Fmodified.jpg%3FExpires%3D2075494478%26AWSAccessKeyId%3DAKIAJO2PPFO3JEGRU4ZQ%26Signature%3DZvjWU0tKo6rLyN1ET2p6zBGQ8bI%253D&request_id=f6c4b9e6-9efb-11e9-b199-005056a7ce13&account_id=&allow_svg=true&type=regular&display_name=Joseph%20Tribbiani&without_user_pic=false" 2019/07/05 08:07:42 [info] 12759#12759: *32118 [lua] rewrite_by_lua(uas-base-location.conf:48):5: req(f6c4b9e6-9efb-11e9-b199-005056a7ce13): Making outbound subrequest to get avatar by direct url to "glipdevnet-rndtapams.s3.amazonaws.com": https://glipdevnet-rndtapams.s3.amazonaws.com/web/customer_files/2383884/modified.jpg?Expires=2075494478&AWSAccessKeyId=AKIAJO2PPFO3JEGRU4ZQ&Signature=ZvjWU0tKo6rLyN1ET2p6zBGQ8bI%3D ..., client: 10.62.134.38, server: , request: "GET /rcvideo/v1/bridges/rnd01-t11-ndb01f1741f9416bc12ca506d77/meetings/rnd01-t11-ndb01f1741f9416bc12ca506d77_1562314057547!vi11-1/participants/3a9d_2571/profile-image/584x584?access_token=QU1TMDJQMDFQQVMwMHxBQUFXdm8yZ3hqY2NiZ0NvSXNReTFqT2FvZkFCTVhUNkRKdUNJdHBrazJ4dWJyWFl2akJqeVlUNmVQejJIVHRCRi1DdG5laEVYQnJSbVpXV0FRS3hHRVFwamlILW1haC1Ja1R4YnA4cWgzWlFZLWM0UWkzQm9iYmRWQUNKRnNtZ0NfWTRpeDJnMVFRak5zRkRtaFBWM0dId3dQUTdkZ1dnQU82bjBBM3ZsbWRlSlk4b215dUxjSHowSWR4NjRyR296b1NrTzBUOWduWFNzNUh0QllSQmNkbEl8Q25FdXJBfFlyRUFjVzY0MzdFOWZHeVotWE1Gb1F8QUE&allowSvg=true HTTP/1.1", host: "rnd01-t08-pwr01.lab.nordigy.ru", referrer: "https://vi11-1-v.lab.nordigy.ru/conf/on/644926345" 2019/07/05 08:07:42 [debug] 12759#12759: *32118 [lua] rewrite_by_lua(uas-base-location.conf:48):6: req(f6c4b9e6-9efb-11e9-b199-005056a7ce13): Additional info: size: 584x584 2019/07/05 08:07:42 [debug] 12759#12759: *32118 [lua] log_by_lua(uas-base-location.conf:53):2: resp(f6c4b9e6-9efb-11e9-b199-005056a7ce13): Avatar fetched by url 2019/07/05 08:07:42 [info] 12759#12759: *32118 [lua] log_by_lua(uas-base-location.conf:53):3: resp(f6c4b9e6-9efb-11e9-b199-005056a7ce13): Upstream status: 200 while logging request, client: 10.62.134.38, server: , request: "GET /rcvideo/v1/bridges/rnd01-t11-ndb01f1741f9416bc12ca506d77/meetings/rnd01-t11-ndb01f1741f9416bc12ca506d77_1562314057547!vi11-1/participants/3a9d_2571/profile-image/584x584?access_token=QU1TMDJQMDFQQVMwMHxBQUFXdm8yZ3hqY2NiZ0NvSXNReTFqT2FvZkFCTVhUNkRKdUNJdHBrazJ4dWJyWFl2akJqeVlUNmVQejJIVHRCRi1DdG5laEVYQnJSbVpXV0FRS3hHRVFwamlILW1haC1Ja1R4YnA4cWgzWlFZLWM0UWkzQm9iYmRWQUNKRnNtZ0NfWTRpeDJnMVFRak5zRkRtaFBWM0dId3dQUTdkZ1dnQU82bjBBM3ZsbWRlSlk4b215dUxjSHowSWR4NjRyR296b1NrTzBUOWduWFNzNUh0QllSQmNkbEl8Q25FdXJBfFlyRUFjVzY0MzdFOWZHeVotWE1Gb1F8QUE&allowSvg=true HTTP/1.1", host: "rnd01-t08-pwr01.lab.nordigy.ru", referrer: "https://vi11-1-v.lab.nordigy.ru/conf/on/644926345" '; $subst = "$2"; $result = preg_replace($re, $subst, $str); echo "The result of the substitution is ".$result;

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php