1CSS::Squish(3) User Contributed Perl Documentation CSS::Squish(3)
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6 CSS::Squish - Compact many CSS files into one big file
7
9 use CSS::Squish;
10 my $concatenated = CSS::Squish->concatenate(@files);
11 my $squisher = CSS::Squish->new( roots => ['/root1', '/root2'] );
13 my $concatenated = $squisher->concatenate(@files);
14
16 This module takes a list of CSS files and concatenates them, making
17 sure to honor any valid @import statements included in the files.
18 The benefit of this is that you get to keep your CSS as individual
20 files, but can serve it to users in one big file, saving the overhead
21 of possibly dozens of HTTP requests.
22 Following the CSS 2.1 spec, @import statements must be the first rules
24 in a CSS file. Media-specific @import statements will be honored by
25 enclosing the included file in an @media rule. This has the side
26 effect of actually improving compatibility in Internet Explorer, which
27 ignores media-specific @import rules but understands @media rules.
28 It is possible that future versions will include methods to compact
30 whitespace and other parts of the CSS itself, but this functionality is
31 not supported at the current time.
32
34 new( [roots=>[...]] )
35 A constructor. For backward compatibility with versions prior to 0.06
36 you can still call everything as a class method, but should remember
37 that roots are shared between all callers in this case.
38 if you're using persistent environment (like mod_perl) then it's very
40 recomended to use objects.
41 concatenate( @files )
43 Takes a list of files to concatenate and returns the results as one big
44 scalar.
45 concatenate_to( $dest, @files )
47 Takes a filehandle to print to and a list of files to concatenate.
48 "concatenate" uses this method with an "open"ed scalar.
49
51 The following methods help map URIs to files and find them on the disk.
52 In common situation you control CSS and can adopt it to use imports
54 with relative URIs and most probably only have to set root(s).
55 However, you can subclass these methods to parse css files before
57 submitting, implement advanced mapping of URIs to file system and other
58 things.
59 Mapping works in the following way. When you call concatenate method we
61 get content of file using file_handle method which as well lookup files
62 in roots. If roots are not defined then files are treated as absolute
63 paths or relative to the current directory. Using of absolute paths is
64 not recommended as unhide server dirrectory layout to clients in css
65 comments and as well don't allow to handle @import commands with
66 absolute URIs. When files is found we parse its content for @import
67 commands. On each URI we call resolve_uri method that convert absolute
68 and relative URIs into file paths.
69 Here is example of processing:
71 roots: /www/overlay/, /www/shared/
73 $squisher->concatenate('/css/main.css');
75 ->file_handle('/css/main.css');
77 ->resolve_file('/css/main.css');
78 <- '/www/shared/css/main.css';
79 <- handle;
80 content parsing
82 find '@import url(nav.css)'
83 -> resolve_uri('nav.css', '/css/main.css');
84 <- '/css/nav.css';
85 ... recursivly process file
86 find '@import url(/css/another.css)'
87 -> resolve_uri('/css/another.css', '/css/main.css');
88 <- '/css/another.css'
89 ...
90 roots( @dirs )
92 A getter/setter for paths to search when looking for files.
93 The paths specified here are searched for files. This is useful if your
95 server has multiple document roots or document root doesn't match the
96 current dir.
97 See also 'resolve_file' below.
99 file_handle( $file )
101 Takes a path to a file, resolves (see resolve_file) it and returns a
102 handle.
103 Returns undef if file couldn't be resolved or it's impossible to open
105 file.
106 You can subclass it to filter content, process it with templating
108 system or generate it on the fly:
109 package My::CSS::Squish;
111 use base qw(CSS::Squish);
112 sub file_handle {
114 my $self = shift;
115 my $file = shift;
116 my $content = $self->my_prepare_content($file);
118 return undef unless defined $content;
119 open my $fh, "<", \$content or warn "Couldn't open handle: $!";
121 return $fh;
122 }
123 Note that the file is not resolved yet and is relative to the root(s),
125 so you have to resolve it yourself or call resolve_file method.
126 resolve_file( $file )
128 Lookup file in the root(s) and returns first path it found or undef.
129 When roots are not set just checks if file exists.
131 _resolve_file( $file, @roots )
133 DEPRECATED. This private method is deprecated and do nothing useful
134 except maintaining backwards compatibility. If you were using it then
135 most probably to find files in roots before submitting them into
136 concatenate method. Now, it's not required and this method returns back
137 file path without changes.
138 resolve_uri( $uri_string, $base_file )
140 Takes an URI and base file path and transforms it into new file path.
141
143 At the current time, comments are not skipped. This means comments
144 happening before @import statements at the top of a file will cause the
145 @import rules to not be parsed. Make sure the @import rules are the
146 very first thing in the file (and only one per line). Processing of
147 @import rules stops as soon as the first line that doesn't match an
148 @import rule is encountered.
149 All other bugs should be reported via
151 <http://rt.cpan.org/Public/Dist/Display.html?Name=CSS-Squish> or
152 bug-CSS-Squish@rt.cpan.org.
153
155 Thomas Sibley <trs@bestpractical.com>, Ruslan Zakirov
156 <ruz@bestpractical.com>
157
159 Copyright (c) 2006.
160 This library is free software; you can redistribute it and/or modify it
162 under the same terms as Perl itself, either Perl version 5.8.3 or, at
163 your option, any later version of Perl 5 you may have available.
164perl v5.36.0 2023-01-20 CSS::Squish(3)