URI::Find(3) User Contributed Perl Documentation URI::Find(3)NAMEURI::Find - Find URIs in arbitrary text
SYNOPSIS
require URI::Find;
my $finder = URI::Find->new(\&callback);
$how_many_found = $finder->find(\$text);
DESCRIPTION
This module does one thing: Finds URIs and URLs in plain text. It
finds them quickly and it finds them all (or what URI::URL considers a
URI to be.) It only finds URIs which include a scheme (http:// or the
like), for something a bit less strict have a look at
URI::Find::Schemeless.
For a command-line interface, urifind is provided.
Public Methods
new
my $finder = URI::Find->new(\&callback);
Creates a new URI::Find object.
&callback is a function which is called on each URI found. It is
passed two arguments, the first is a URI::URL object representing
the URI found. The second is the original text of the URI found.
The return value of the callback will replace the original URI in
the text.
find
my $how_many_found = $finder->find(\$text);
$text is a string to search and possibly modify with your callback.
Alternatively, "find" can be called with a replacement function for
the rest of the text:
use CGI qw(escapeHTML);
# ...
my $how_many_found = $finder->find(\$text, \&escapeHTML);
will not only call the callback function for every URL found (and
perform the replacement instructions therein), but also run the
rest of the text through "escapeHTML()". This makes it easier to
turn plain text which contains URLs into HTML (see example below).
Protected Methods
I got a bunch of mail from people asking if I'd add certain features to
URI::Find. Most wanted the search to be less restrictive, do more
heuristics, etc... Since many of the requests were contradictory, I'm
letting people create their own custom subclasses to do what they want.
The following are methods internal to URI::Find which a subclass can
override to change the way URI::Find acts. They are only to be called
inside a URI::Find subclass. Users of this module are NOT to use these
methods.
uri_re
my $uri_re = $self->uri_re;
Returns the regex for finding absolute, schemed URIs
(http://www.foo.com and such). This, combined with
schemeless_uri_re() is what finds candidate URIs.
Usually this method does not have to be overridden.
schemeless_uri_re
my $schemeless_re = $self->schemeless_uri_re;
Returns the regex for finding schemeless URIs (www.foo.com and
such) and other things which might be URIs. By default this will
match nothing (though it used to try to find schemeless URIs which
started with "www" and "ftp").
Many people will want to override this method. See
URI::Find::Schemeless for a subclass does a reasonable job of
finding URIs which might be missing the scheme.
uric_set
my $uric_set = $self->uric_set;
Returns a set matching the 'uric' set defined in RFC 2396 suitable
for putting into a character set ([]) in a regex.
You almost never have to override this.
cruft_set
my $cruft_set = $self->cruft_set;
Returns a set of characters which are considered garbage. Used by
decruft().
decruft
my $uri = $self->decruft($uri);
Sometimes garbage characters like periods and parenthesis get
accidentally matched along with the URI. In order for the URI to
be properly identified, it must sometimes be "decrufted", the
garbage characters stripped.
This method takes a candidate URI and strips off any cruft it
finds.
recruft
my $uri = $self->recruft($uri);
This method puts back the cruft taken off with decruft(). This is
necessary because the cruft is destructively removed from the
string before invoking the user's callback, so it has to be put
back afterwards.
schemeless_to_schemed
my $schemed_uri = $self->schemeless_to_schemed($schemeless_uri);
This takes a schemeless URI and returns an absolute, schemed URI.
The standard implementation supplies ftp:// for URIs which start
with ftp., and http:// otherwise.
is_schemed
$obj->is_schemed($uri);
Returns whether or not the given URI is schemed or schemeless.
True for schemed, false for schemeless.
badinvo
__PACKAGE__->badinvo($extra_levels, $msg)
This is used to complain about bogus subroutine/method invocations.
The args are optional.
Old Functions
The old find_uri() function is still around and it works, but its
deprecated.
EXAMPLES
Store a list of all URIs (normalized) in the document.
my @uris;
my $finder = URI::Find->new(sub {
my($uri) = shift;
push @uris, $uri;
});
$finder->find(\$text);
Print the original URI text found and the normalized representation.
my $finder = URI::Find->new(sub {
my($uri, $orig_uri) = @_;
print "The text '$orig_uri' represents '$uri'\n";
return $orig_uri;
});
$finder->find(\$text);
Check each URI in document to see if it exists.
use LWP::Simple;
my $finder = URI::Find->new(sub {
my($uri, $orig_uri) = @_;
if( head $uri ) {
print "$orig_uri is okay\n";
}
else {
print "$orig_uri cannot be found\n";
}
return $orig_uri;
});
$finder->find(\$text);
Turn plain text into HTML, with each URI found wrapped in an HTML
anchor.
use CGI qw(escapeHTML);
use URI::Find;
my $finder = URI::Find->new(sub {
my($uri, $orig_uri) = @_;
return qq|<a href="$uri">$orig_uri</a>|;
});
$finder->find(\$text, \&escapeHTML);
print "<pre>$text</pre>";
NOTES
Will not find URLs with Internationalized Domain Names or pretty much
any non-ascii stuff in them. See
<http://rt.cpan.org/Ticket/Display.html?id=44226>
AUTHOR
Michael G Schwern <schwern@pobox.com> with insight from Uri Gutman,
Greg Bacon, Jeff Pinyan, Roderick Schertler and others.
Roderick Schertler <roderick@argon.org> maintained versions 0.11 to
0.16.
Darren Chamberlain wrote urifind.
LICENSE
Copyright 2000, 2009-2010 by Michael G Schwern <schwern@pobox.com>.
This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
See http://www.perlfoundation.org/artistic_license_1_0
SEE ALSO
urifind, URI::Find::Schemeless, URI::URL, URI, RFC 3986 Appendix C
perl v5.14.1 2011-06-21 URI::Find(3)
