One document matched: draft-gellens-imapext-regex-00.txt
Internet Draft R. Gellens
Document: draft-gellens-imapext-regex-00 QUALCOMM
Expires: September 2000 March 2000
IMAP Regular Expressions SEARCH Extension
Status of this Memo:
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as
Internet-Drafts.
Internet-Drafts are draft documents valid for a maximum of six
months and may be updated, replaced, or obsoleted by other documents
at any time. It is inappropriate to use Internet- Drafts as
reference material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at
<http://www.ietf.org/ietf/1id-abstracts.txt>
The list of Internet-Draft Shadow Directories can be accessed at
<http://www.ietf.org/shadow.html>.
A version of this draft document is intended for submission to the
RFC editor as a Proposed Standard for the Internet Community.
Discussion and suggestions for improvement are requested.
Copyright Notice
Copyright (C) The Internet Society 2000. All Rights Reserved.
Gellens Expires September 2000 [Page 1] Internet Draft IMAP Regular Expressions SEARCH Extension March 2000
Table of Contents
1. Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions Used in this Document . . . . . . . . . . . . . . 2
3. Comments . . . . . . . . . . . . . . . . . . . . . . . . . . 2
4. Open Issues . . . . . . . . . . . . . . . . . . . . . . . . . 2
5. REGEX Modifier to SEARCH (and UID SEARCH) Criteria . . . . . 3
6. Formal Syntax Changes . . . . . . . . . . . . . . . . . . . . 3
7. Regular Expression Details . . . . . . . . . . . . . . . . . 3
8. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 4
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 4
10. Security Considerations . . . . . . . . . . . . . . . . . . . 5
11. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . 5
12. Author's Address . . . . . . . . . . . . . . . . . . . . . . 5
13. Full Copyright Statement . . . . . . . . . . . . . . . . . . 5
1. Abstract
This memo describes a regular-expression search facility for the
[IMAP] protocol.
A server advertises support for this facility by the capability name
REGEX.
2. Conventions Used in this Document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [KEYWORDS].
3. Comments
Public comments can be sent to the IETF IMAP Extensions mailing
list, <ietf-imapext@imc.org>. To subscribe, send a message to
<ietf-imapext-request@imc.org> with the word SUBSCRIBE as the body.
Private comments should be sent to the author.
4. Open Issues
- Should the regular expression syntax be specified in a simple
form, as is done here, or should it be a reference to a published,
more complex form, such as POSIX 1003.2?
- Should ^ and $ be used for token, line, or a message part (such as
a header field)?
Gellens Expires September 2000 [Page 2] Internet Draft IMAP Regular Expressions SEARCH Extension March 2000
- Should REGEX come after the search key?
- The current Formal Syntax allows for sillyness such as SEARCH
REGEXP REGEXP CC "gork"
5. REGEX Modifier to SEARCH (and UID SEARCH) Criteria
This extension adds an additional optional REGEXP modifier to all
SEARCH criteria which take strings. When this modifier is present,
the search criteria string is interpreted as a regular expression,
as described in section 7.
If the string supplied with the search criteria does not contain a
valid regular expression, the server MUST return a BAD response.
If the search criteria does not take a string, the server MUST
return a BAD response.
6. Formal Syntax Changes
This section described the changes to the Formal Syntax of the IMAP
protocol, using [ABNF]:
search-key =/ REGEX SP search-key
; modifies existing IMAP search-key so
; that string values in search-key are treated
; as regular expressions for pattern matching
7. Regular Expression Details
The regular expression syntax described in this section is a subset
of that used in many applications and systems. It is however very
simple and does not include the logical operators AND and OR.
Searches using regular expressions are always substring matches
except when the regular expression contains the characters '^' or
'$'.
Character Function
--------- --------
<any except those
listed in this table> Matches itself
. Matches any character
a* Matches zero or more 'a's
a+ Matches one or more 'a's
[ab] Matches 'a' or 'b'
[a-c] Matches 'a', 'b' or 'c'
[^ab] Matches any character
except 'a' or 'b'
Gellens Expires September 2000 [Page 3] Internet Draft IMAP Regular Expressions SEARCH Extension March 2000
^ Matches beginning of
a token
$ Matches end of a token
\ Next character matches
itself
Examples
---------
String Matches Doesn't Match
------- ------- -------------
hello xhelloy heello
h.llo hello helio
h.*o hello helloa
h[a-f]llo hello hgllo
^he.* hello ehello
.*lo$ hello helloo
hel+o hello helo
8. Examples
This example finds messages that have "MAKE*MONEY*FAST" in the
subject, but not "MAKE!MONEY!FAST":
C: Z SEARCH REGEX SUBJECT "MAKE[ _\-\*]+MONEY[ _\-\*]+FAST"
S: * SEARCH 2 22 98 2048
S: Z OK SEARCH Completed
This example uses an invalid regular expression:
C: Y SEARCH REGEX TO ".["
S: Y BAD Invalid regular expression syntax
This example uses REGEX with a search criteria that does not take a
string:
C: X SEARCH REGEX LARGER 10000
S: X BAD Cannot use regular expressions with the LARGER criteria
This example searches for messages without the \ANSWERED flag where
the envelope from matches the regular expression "mump.*wump" and
the text matches the substring "a[0-9]*" (note that the text
criteria is not a regular expression):
C: W SEARCH UNANSWERED REGEX FROM "mump.*wump" TEXT "a[0-9]*"
S: * SEARCH 3
S: W OK SEARCH Completed
Gellens Expires September 2000 [Page 4] Internet Draft IMAP Regular Expressions SEARCH Extension March 2000
9. References
[ABNF] Crocker, Overell, "Augmented BNF for Syntax Specifications:
ABNF", RFC 2234, Internet Mail Consortium, Demon Internet Ltd.,
November 1997. <ftp://ftp.isi.edu/in-notes/rfc2234.txt>
[IMAP4] Crispin, "Internet Message Access Protocol - Version 4rev1",
RFC 2060, University of Washington, December 1996.
[KEYWORDS] Bradner, "Key words for use in RFCs to Indicate
Requirement Levels", RFC 2119, Harvard University, March 1997.
<ftp://ftp.isi.edu/in-notes/rfc2119.txt>
10. Security Considerations
This extension does not alter the security semantics of IMAP.
11. Acknowledgments
The table in section 7 is based on the one in RFC 1835.
12. Author's Address
Randall Gellens +1 858 651 5115
QUALCOMM Incorporated randy@qualcomm.com
5775 Morehouse Drive
San Diego, CA 92121-2779
U.S.A.
13. Full Copyright Statement
Copyright (C) The Internet Society 2000. All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph
are included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
Gellens Expires September 2000 [Page 5] Internet Draft IMAP Regular Expressions SEARCH Extension March 2000
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Gellens Expires September 2000 [Page 6]
| PAFTECH AB 2003-2026 | 2026-04-24 09:17:54 |