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# ABSTRACT: File utility helpers
$Dancer2::FileUtils::VERSION = '1.1.2';
use strict;
use Carp;
use Exporter 'import';
our @EXPORT_OK = qw(
dirname open_file path read_file_content read_glob_content
path_or_empty set_file_mode normalize_path escape_filename
);
sub path {
my @parts = @_;
my $path = File::Spec->catfile(@parts);
return normalize_path($path);
}
sub path_or_empty {
my @parts = @_;
my $path = path(@parts);
# return empty if it doesn't exist
return -e $path ? $path : '';
}
sub dirname { File::Basename::dirname(@_) }
sub set_file_mode {
my $fh = shift;
my $charset = 'utf-8';
binmode $fh, ":encoding($charset)";
return $fh;
}
sub open_file {
my ( $mode, $filename ) = @_;
open my $fh, $mode, $filename
or croak "Can't open '$filename' using mode '$mode': $!";
return set_file_mode($fh);
}
sub read_file_content {
my $file = shift or return;
my $fh = open_file( '<', $file );
return wantarray
? read_glob_content($fh)
: scalar read_glob_content($fh);
}
sub read_glob_content {
my $fh = shift;
my @content = <$fh>;
close $fh;
return wantarray ? @content : join '', @content;
}
sub normalize_path {
# this is a revised version of what is described in
# by Mitch Frazier
my $path = shift or return;
my $seqregex = qr{
[^/]* # anything without a slash
/\.\.(/|\z) # that is accompanied by two dots as such
}x;
$path =~ s{/\./}{/}g;
while ( $path =~ s{$seqregex}{} ) {}
$path =~ s{^//}{/};
return $path;
}
sub escape_filename {
my $filename = shift or return;
# based on escaping used in CHI::Driver. Our use-case is one-way,
# so we allow utf8 chars to be escaped, but NEVER do the inverse
# operation.
$filename =~ s/([^A-Za-z0-9_\=\-\~])/sprintf("+%02x", ord($1))/ge;
return $filename;
}
1;
__END__
=pod
=encoding UTF-8
=head1 NAME
Dancer2::FileUtils - File utility helpers
=head1 VERSION
version 1.1.2
=head1 SYNOPSIS
use Dancer2::FileUtils qw/dirname path path_or_empty/;
# for 'path/to/file'
my $dir = dirname($path); # returns 'path/to'
my $path = path($path); # returns '/abs/path/to/file'
my $path = path_or_empty($path); # returns '' if file doesn't exist
use Dancer2::FileUtils qw/path read_file_content/;
my $content = read_file_content( path( 'folder', 'folder', 'file' ) );
my @content = read_file_content( path( 'folder', 'folder', 'file' ) );
use Dancer2::FileUtils qw/read_glob_content set_file_mode/;
open my $fh, '<', $file or die "$!\n";
set_file_mode($fh);
my @content = read_glob_content($fh);
my $content = read_glob_content($fh);
use Dancer2::FileUtils qw/open_file/;
my $fh = open_file('<', $file) or die $message;
use Dancer2::FileUtils 'set_file_mode';
set_file_mode($fh);
=head1 DESCRIPTION
Dancer2::FileUtils includes a few file related utilities that Dancer2
uses internally. Developers may use it instead of writing their own
file reading subroutines or using additional modules.
=head1 FUNCTIONS
=head2 my $path = path( 'folder', 'folder', 'filename');
Provides comfortable path resolution, internally using L<File::Spec>. 'path'
does not verify paths, it just normalizes the path.
=head2 my $path = path_or_empty('folder, 'folder','filename');
Like path, but returns '' if path doesn't exist.
=head2 dirname
use Dancer2::FileUtils 'dirname';
my $dir = dirname($path);
Exposes L<File::Basename>'s I<dirname>, to allow fetching a directory name from
a path. On most OS, returns all but last level of file path. See
L<File::Basename> for details.
=head2 set_file_mode($fh);
use Dancer2::FileUtils 'set_file_mode';
set_file_mode($fh);
Applies charset setting from Dancer2's configuration. Defaults to utf-8 if no
charset setting.
=head2 my $fh = open_file('<', $file) or die $message;
use Dancer2::FileUtils 'open_file';
my $fh = open_file('<', $file) or die $message;
Calls open and returns a filehandle. Takes in account the 'charset' setting
from Dancer2's configuration to open the file in the proper encoding (or
defaults to utf-8 if setting not present).
=head2 my $content = read_file_content($file);
use Dancer2::FileUtils 'read_file_content';
my @content = read_file_content($file);
my $content = read_file_content($file);
Returns either the content of a file (whose filename is the input), or I<undef>
if the file could not be opened.
In array context it returns each line (as defined by $/) as a separate element;
in scalar context returns the entire contents of the file.
=head2 my $content = read_glob_content($fh);
use Dancer2::FileUtils 'read_glob_content';
open my $fh, '<', $file or die "$!\n";
binmode $fh, ':encoding(utf-8)';
my @content = read_glob_content($fh);
my $content = read_glob_content($fh);
Similar to I<read_file_content>, only it accepts a file handle. It is
assumed that the appropriate PerlIO layers are applied to the file handle.
Returns the content and B<closes the file handle>.
=head2 my $norm_path=normalize_path ($path);
=head2 my $escaped_filename = escape_filename( $filename );
Escapes characters in a filename that may alter a path when concatenated.
use Dancer2::FileUtils 'escape_filename';
my $safe = escape_filename( "a/../b.txt" ); # a+2f+2e+2e+2fb+2etxt
=head1 EXPORT
Nothing by default. You can provide a list of subroutines to import.
=head1 AUTHOR
Dancer Core Developers
=head1 COPYRIGHT AND LICENSE
This software is copyright (c) 2024 by Alexis Sukrieh.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.
=cut