uri_validate.py

#!/usr/bin/env python

"""
Regex for URIs

These regex are directly derived from the collected ABNF in RFC3986
(except for DIGIT, ALPHA and HEXDIG, defined by RFC2234).

They should be processed with re.VERBOSE.
"""

__license__ = """
Copyright (c) 2009 Mark Nottingham (code portions)

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
"""

### basics

DIGIT = r"[\x30-\x39]"

ALPHA = r"[\x41-\x5A\x61-\x7A]"

HEXDIG = r"[\x30-\x39A-Fa-f]"

#   pct-encoded   = "%" HEXDIG HEXDIG
pct_encoded = r" %% %(HEXDIG)s %(HEXDIG)s"  % locals()

#   unreserved    = ALPHA / DIGIT / "-" / "." / "_" / "~"
unreserved = r"(?: %(ALPHA)s | %(DIGIT)s | \- | \. | _ | ~ )"  % locals()

#   gen-delims    = ":" / "/" / "?" / "#" / "[" / "]" / "@"
gen_delims = r"(?: : | / | \? | \# | \[ | \] | @ )"

#   sub-delims    = "!" / "$" / "&" / "'" / "(" / ")"
#                 / "*" / "+" / "," / ";" / "="
sub_delims = r"""(?: ! | \$ | & | ' | \( | \) |
                     \* | \+ | , | ; | = )"""

#   pchar         = unreserved / pct-encoded / sub-delims / ":" / "@"
pchar = r"(?: %(unreserved)s | %(pct_encoded)s | %(sub_delims)s | : | @ )" % locals()

#   reserved      = gen-delims / sub-delims
reserved = r"(?: %(gen_delims)s | %(sub_delims)s )" % locals()


### scheme

#   scheme        = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )
scheme = r"%(ALPHA)s (?: %(ALPHA)s | %(DIGIT)s | \+ | \- | \. )*" % locals()


### authority

#   dec-octet     = DIGIT                 ; 0-9
#                 / %x31-39 DIGIT         ; 10-99
#                 / "1" 2DIGIT            ; 100-199
#                 / "2" %x30-34 DIGIT     ; 200-249
#                 / "25" %x30-35          ; 250-255
dec_octet = r"""(?: %(DIGIT)s |
                    [\x31-\x39] %(DIGIT)s |
                    1 %(DIGIT)s{2} |
                    2 [\x30-\x34] %(DIGIT)s |
                    25 [\x30-\x35]
                )
""" % locals()

#  IPv4address   = dec-octet "." dec-octet "." dec-octet "." dec-octet
IPv4address = r"%(dec_octet)s \. %(dec_octet)s \. %(dec_octet)s \. %(dec_octet)s" % locals()

#  h16           = 1*4HEXDIG
h16 = r"(?: %(HEXDIG)s ){1,4}" % locals()

#  ls32          = ( h16 ":" h16 ) / IPv4address
ls32 = r"(?: (?: %(h16)s : %(h16)s ) | %(IPv4address)s )" % locals()

#   IPv6address   =                            6( h16 ":" ) ls32
#                 /                       "::" 5( h16 ":" ) ls32
#                 / [               h16 ] "::" 4( h16 ":" ) ls32
#                 / [ *1( h16 ":" ) h16 ] "::" 3( h16 ":" ) ls32
#                 / [ *2( h16 ":" ) h16 ] "::" 2( h16 ":" ) ls32
#                 / [ *3( h16 ":" ) h16 ] "::"    h16 ":"   ls32
#                 / [ *4( h16 ":" ) h16 ] "::"              ls32
#                 / [ *5( h16 ":" ) h16 ] "::"              h16
#                 / [ *6( h16 ":" ) h16 ] "::"
IPv6address = r"""(?:                                  (?: %(h16)s : ){6} %(ls32)s |
                                                    :: (?: %(h16)s : ){5} %(ls32)s |
                                            %(h16)s :: (?: %(h16)s : ){4} %(ls32)s |
                         (?: %(h16)s : )    %(h16)s :: (?: %(h16)s : ){3} %(ls32)s |
                         (?: %(h16)s : ){2} %(h16)s :: (?: %(h16)s : ){2} %(ls32)s |
                         (?: %(h16)s : ){3} %(h16)s ::     %(h16)s :      %(ls32)s |
                         (?: %(h16)s : ){4} %(h16)s ::                    %(ls32)s |
                         (?: %(h16)s : ){5} %(h16)s ::                    %(h16)s  |
                         (?: %(h16)s : ){6} %(h16)s ::
                  )
""" % locals()

#   IPvFuture     = "v" 1*HEXDIG "." 1*( unreserved / sub-delims / ":" )
IPvFuture = r"v %(HEXDIG)s+ \. (?: %(unreserved)s | %(sub_delims)s | : )+" % locals()

#   IP-literal    = "[" ( IPv6address / IPvFuture  ) "]"
IP_literal = r"\[ (?: %(IPv6address)s | %(IPvFuture)s ) \]" % locals()

#   reg-name      = *( unreserved / pct-encoded / sub-delims )
reg_name = r"(?: %(unreserved)s | %(pct_encoded)s | %(sub_delims)s )*" % locals()

#   userinfo      = *( unreserved / pct-encoded / sub-delims / ":" )
userinfo = r"(?: %(unreserved)s | %(pct_encoded)s | %(sub_delims)s | : )" % locals()

#   host          = IP-literal / IPv4address / reg-name
host = r"(?: %(IP_literal)s | %(IPv4address)s | %(reg_name)s )" % locals()

#   port          = *DIGIT
port = r"(?: %(DIGIT)s )*" % locals()

#   authority     = [ userinfo "@" ] host [ ":" port ]
authority = r"(?: %(userinfo)s @)? %(host)s (?: : %(port)s)?" % locals()



### Path

#   segment       = *pchar
segment = r"%(pchar)s*" % locals()

#   segment-nz    = 1*pchar
segment_nz = r"%(pchar)s+" % locals()

#   segment-nz-nc = 1*( unreserved / pct-encoded / sub-delims / "@" )
#                 ; non-zero-length segment without any colon ":"
segment_nz_nc = r"(?: %(unreserved)s | %(pct_encoded)s | %(sub_delims)s | @ )+" % locals()

#   path-abempty  = *( "/" segment )
path_abempty = r"(?: / %(segment)s )*" % locals()

#   path-absolute = "/" [ segment-nz *( "/" segment ) ]
path_absolute = r"/ (?: %(segment_nz)s (?: / %(segment)s )* )?" % locals()

#   path-noscheme = segment-nz-nc *( "/" segment )
path_noscheme = r"%(segment_nz_nc)s (?: / %(segment)s )*" % locals()

#   path-rootless = segment-nz *( "/" segment )
path_rootless = r"%(segment_nz)s (?: / %(segment)s )*" % locals()

#   path-empty    = 0<pchar>
path_empty = r""  ### FIXME

#   path          = path-abempty    ; begins with "/" or is empty
#                 / path-absolute   ; begins with "/" but not "//"
#                 / path-noscheme   ; begins with a non-colon segment
#                 / path-rootless   ; begins with a segment
#                 / path-empty      ; zero characters
path = r"""(?: %(path_abempty)s |
               %(path_absolute)s |
               %(path_noscheme)s |
               %(path_rootless)s |
               %(path_empty)s
            )
""" % locals()



### Query and Fragment

#   query         = *( pchar / "/" / "?" )
query = r"(?: %(pchar)s | / | \? )*" % locals()

#   fragment      = *( pchar / "/" / "?" )
fragment = r"(?: %(pchar)s | / | \? )*" % locals()



### URIs

#   hier-part     = "//" authority path-abempty
#                 / path-absolute
#                 / path-rootless
#                 / path-empty
hier_part = r"""(?: (?: // %(authority)s %(path_abempty)s ) |
                    %(path_absolute)s |
                    %(path_rootless)s |
                    %(path_empty)s
                )
""" % locals()

#   relative-part = "//" authority path-abempty
#                 / path-absolute
#                 / path-noscheme
#                 / path-empty
relative_part = r"""(?: (?: // %(authority)s %(path_abempty)s ) |
                        %(path_absolute)s |
                        %(path_noscheme)s |
                        %(path_empty)s
                    )
""" % locals()

#   relative-ref  = relative-part [ "?" query ] [ "#" fragment ]
relative_ref = r"%(relative_part)s (?: \? %(query)s)? (?: \# %(fragment)s)?" % locals()

#   URI           = scheme ":" hier-part [ "?" query ] [ "#" fragment ]
URI = r"(?: %(scheme)s : %(hier_part)s (?: \? %(query)s )? (?: \# %(fragment)s )? )" % locals()

#   URI-reference = URI / relative-ref
URI_reference = r"(?: %(URI)s | %(relative_ref)s )" % locals()

#   absolute-URI  = scheme ":" hier-part [ "?" query ]
absolute_URI = r"(?: %(scheme)s : %(hier_part)s (?: \? %(query)s )? )" % locals()


if "__main__" == __name__:
        import re
        import sys
        try:
                instr = sys.argv[1]
        except IndexError:
                print "usage: %s test-string" % sys.argv[0]
                sys.exit(1)
        
        print 'testing: "%s"' % instr
        
        print "URI:",
        if re.match("^%s$" % URI, instr, re.VERBOSE):
                print "yes"
        else:
                print "no"
        
        print "URI reference:",
        if re.match("^%s$" % URI_reference, instr, re.VERBOSE):
                print "yes"
        else:
                print "no"
        
        print "Absolute URI:",
        if re.match("^%s$" % absolute_URI, instr, re.VERBOSE):
                print "yes"
        else:
                print "no"