use strict;
use warnings;
package Config::INI::Writer;
$Config::INI::Writer::VERSION = '0.024';
use Mixin::Linewise::Writers;
# ABSTRACT: a subclassable .ini-file emitter
use Carp ();
our @CARP_NOT = qw(Mixin::Linewise::Writers);
#pod =head1 SYNOPSIS
#pod
#pod If <$hash> contains:
#pod
#pod {
#pod '_' => { admin => 'rjbs' },
#pod rjbs => {
#pod awesome => 'yes',
#pod height => q{5' 10"},
#pod },
#pod mj => {
#pod awesome => 'totally',
#pod height => '23"',
#pod },
#pod }
#pod
#pod Then when your program contains:
#pod
#pod Config::INI::Writer->write_file($hash, 'family.ini');
#pod
#pod F<family.ini> will contains:
#pod
#pod admin = rjbs
#pod
#pod [rjbs]
#pod awesome = yes
#pod height = 5' 10"
#pod
#pod [mj]
#pod awesome = totally
#pod height = 23"
#pod
#pod =head1 DESCRIPTION
#pod
#pod Config::INI::Writer is I<yet another> config module implementing I<yet another>
#pod slightly different take on the undeniably easy to read L<".ini" file
#pod format|Config::INI>. Its default behavior is quite similar to that of
#pod L<Config::Tiny>, on which it is based.
#pod
#pod The chief difference is that Config::INI::Writer is designed to be subclassed
#pod to allow for side-effects and self-reconfiguration to occur during the course
#pod of reading its input.
#pod
#pod =head1 METHODS FOR WRITING CONFIG
#pod
#pod There are three writer methods, C<write_string>, C<write_file>, and
#pod C<write_handle>. The first two are implemented in terms of the third. It
#pod iterates over a collection of data, emitting lines to the filehandle as it
#pod goes. The lines are generated by events produced by iterating over the data.
#pod Those events are detailed below in the L</METHODS FOR SUBCLASSING> section.
#pod
#pod The given data should be a hashref of hashrefs:
#pod
#pod {
#pod section_name_1 => { prop1 => 'value1', prop2 => 'value2' },
#pod section_name_2 => ...
#pod }
#pod
#pod ...or an arrayref of section name and arrayref pairs:
#pod
#pod [
#pod section_name_1 => [ prop1 => 'value1', prop2 => 'value2' ],
#pod section_name_2 => ...
#pod ]
#pod
#pod ...or a combination of those:
#pod
#pod [
#pod section_name_1 => { prop1 => 'value1', prop2 => 'value2' },
#pod section_name_2 => [ prop3 => 'value3', prop4 => 'value4' ],
#pod section_name_3 => ...
#pod ]
#pod
#pod
#pod All the reader methods throw an exception when they encounter an error.
#pod
#pod =head2 write_file
#pod
#pod Config::INI::Writer->write_file($input, $filename);
#pod
#pod This method writes out the configuration represented by C<$data> to the file
#pod named by C<$filename>. If a file by that name exists, it is overwritten.
#pod
#pod This method will either succeed or raise an exception. (Its return value is
#pod not defined.)
#pod
#pod =head2 write_string
#pod
#pod my $string = Config::INI::Writer->write_string($input);
#pod
#pod This method returns a string containing the INI content describing the given
#pod data.
#pod
#pod =head2 write_handle
#pod
#pod Config::INI::Writer->write_handle($input, $handle);
#pod
#pod This method writes the data in C<$data> to the IO::Handle-like object in
#pod C<$handle>. This method should either succeed or throw an exception.
#pod
#pod =cut
sub write_handle {
my ($invocant, $input, $handle) = @_;
my $self = ref $invocant ? $invocant : $invocant->new;
$input = $self->preprocess_input($input);
$self->validate_input($input);
my $starting_section_name = $self->starting_section;
SECTION: for (my $i = 0; $i < $#$input; $i += 2) {
my ($section_name, $section_data) = @$input[ $i, $i + 1 ];
$self->change_section($section_name);
$handle->print($self->stringify_section($section_data))
or Carp::croak "error writing section $section_name: $!";
$self->finish_section;
}
}
#pod =head1 METHODS FOR SUBCLASSING
#pod
#pod These are the methods you need to understand and possibly change when
#pod subclassing Config::INI::Reader to handle a different format of input.
#pod
#pod =head2 preprocess_input
#pod
#pod my $processed_input = $writer->preprocess_input($input_data);
#pod
#pod This method is called to ensure that the data given to the C<write_*> methods
#pod are in a canonical form for processing and emitting. The default
#pod implementation converts hashrefs to arrayrefs and, if the input is a hashref,
#pod moves the L</starting_section> to the beginning of the produced arrayref.
#pod
#pod In other words, given:
#pod
#pod {
#pod section_1 => { a => 1, b => 2 },
#pod section_2 => { c => 3, c => 4 },
#pod _ => { d => 5, e => 6 },
#pod }
#pod
#pod This method will return:
#pod
#pod [
#pod _ => [ d => 5, e => 6 ],
#pod section_2 => [ c => 3, c => 4 ],
#pod section_1 => [ a => 1, b => 2 ],
#pod ]
#pod
#pod The only guaranteed ordering when hashes are provided as input is that the
#pod starting section will appear first.
#pod
#pod =cut
sub preprocess_input {
my ($self, $data) = @_;
my @new_data;
if (ref $data eq 'HASH') {
my $starting_section_name = $self->starting_section;
for my $name (
$starting_section_name,
grep { $_ ne $starting_section_name } keys %$data
) {
my $props = $data->{ $name };
next unless defined $props;
push @new_data,
$name => ((ref($props) || '') eq 'HASH') ? [ %$props ] : $props;
}
} elsif (ref $data eq 'ARRAY') {
for (my $i = 0; $i < $#$data; $i += 2) {
my ($name, $props) = @$data[ $i, $i + 1 ];
push @new_data, $name, (ref $props eq 'HASH') ? [ %$props ] : $props;
}
} else {
my $class = ref $self;
Carp::croak "can't output $data via $class";
}
return \@new_data;
}
#pod =head2 validate_section_name
#pod
#pod Carp::croak "section name contains illegal character"
#pod if not $writer->is_valid_section_name($name);
#pod
#pod =cut
sub is_valid_section_name {
my ($self, $name) = @_;
return $name !~ qr/(?:\n|\s;|^\s|\s$)/;
}
#pod =head2 is_valid_property_name
#pod
#pod Carp::croak "property name contains illegal character"
#pod if not $writer->is_valid_property_name($name);
#pod
#pod =cut
sub is_valid_property_name {
my ($self, $property) = @_;
return $property !~ qr/(?:\n|\s;|^\s|\s|=$)/;
}
#pod =head2 is_valid_value
#pod
#pod Carp::croak "value contains illegal character"
#pod if not $writer->is_valid_value($name);
#pod
#pod =cut
sub is_valid_value {
my ($self, $value) = @_;
return $value !~ qr/(?:\n|\s;|^\s|\s$)/;
}
#pod =head2 validate_input
#pod
#pod $writer->validate_input($input);
#pod
#pod This method is called on the input data once they've been preprocessed by
#pod C<L</preprocess_input>>.
#pod
#pod It ensures that the processed input is structurally sound before beginning to
#pod output it. For example, it ensures that no property is ever assigned more than
#pod once in a given section.
#pod
#pod This method either raises an exception or it doesn't.
#pod
#pod =cut
sub validate_input {
my ($self, $input) = @_;
my %seen;
for (my $i = 0; $i < $#$input; $i += 2) {
my ($name, $props) = @$input[ $i, $i + 1 ];
$seen{ $name } ||= {};
Carp::croak "illegal section name '$name'"
if not $self->is_valid_section_name($name);
for (my $j = 0; $j < $#$props; $j += 2) {
my $property = $props->[ $j ];
my $value = $props->[ $j + 1 ];
Carp::croak "property name '$property' contains illegal character"
if not $self->is_valid_property_name($property);
Carp::croak "value for $name.$property contains illegal character"
if defined $value and not $self->is_valid_value($value);
if ( $seen{ $name }{ $property }++ ) {
Carp::croak "multiple assignments found for $name.$property";
}
}
}
}
#pod =head2 change_section
#pod
#pod $writer->change_section($section_name);
#pod
#pod This method is called each time a new section is going to be written out. If
#pod the same section appears twice in a row in the input, this method will still be
#pod called between instances of that section.
#pod
#pod In other words, given this input:
#pod
#pod [
#pod section_1 => [ a => 1 ],
#pod section_1 => [ b => 2 ],
#pod ]
#pod
#pod C<change_section> will be called twice: once before the first C<section_1> and
#pod once before the second C<section_1>.
#pod
#pod =cut
sub change_section {
my ($self, $section_name) = @_;
$self->{current_section} = $section_name;
}
#pod =head2 current_section
#pod
#pod $writer->current_section
#pod
#pod This method returns the section currently being written out.
#pod
#pod =cut
sub current_section {
my ($self) = @_;
return $self->{current_section};
}
#pod =head2 finish_section
#pod
#pod $writer->finish_section
#pod
#pod This method is called after all of the current section's properties have been
#pod written.
#pod
#pod =cut
sub finish_section {
my ($self) = @_;
return $self->{did_section}{ $self->current_section }++;
}
#pod =head2 done_sections
#pod
#pod my @names = $writer->done_sections;
#pod
#pod This method returns a list of all sections that have been written out and
#pod finished. The fact that a section name is returned by C<done_sections> does
#pod not mean that there will be no more data for that section, but that at least
#pod one entire set of data has been written out for it.
#pod
#pod =cut
sub done_sections {
my ($self) = @_;
return keys %{ $self->{did_section} };
}
#pod =head2 stringify_section
#pod
#pod my $string = $writer->stringify_section($props);
#pod
#pod This method returns a string assigning all the properties set in the given
#pod data. This still will include the section header, if needed. (The only case
#pod in which it is not needed is when the C<L</explicit_starting_header>> method
#pod returns false, no other sections have been done, and the section about to be
#pod stringified is the C<L</starting_section>>.
#pod
#pod This method is implemented in terms of C<L</stringify_section_header>> and
#pod C<L</stringify_section_data>>.
#pod
#pod =cut
sub stringify_section {
my ($self, $section_data) = @_;
my $output = '';
my $current_section_name = $self->current_section;
my $starting_section_name = $self->starting_section;
unless (
$starting_section_name
and $starting_section_name eq $current_section_name
and ! $self->done_sections
and ! $self->explicit_starting_header
) {
$output .= $self->stringify_section_header($self->current_section);
}
$output .= $self->stringify_section_data($section_data);
return $output;
}
#pod =head2 stringify_section_data
#pod
#pod my $string = $writer->stringify_section_data($props)
#pod
#pod This method returns a string containing a series of lines, each containing a
#pod value assignment for the given properties.
#pod
#pod =cut
sub stringify_section_data {
my ($self, $values) = @_;
my $output = '';
for (my $i = 0; $i < $#$values; $i += 2) {
$output .= $self->stringify_value_assignment(@$values[ $i, $i + 1]);
}
return $output;
}
#pod =head2 stringify_value_assignment
#pod
#pod my $string = $writer->stringify_value_assignment($name => $value);
#pod
#pod This method returns a string that assigns a value to a named property. If the
#pod value is undefined, an empty string is returned.
#pod
#pod =cut
sub stringify_value_assignment {
my ($self, $name, $value) = @_;
return '' unless defined $value;
return $name . ' = ' . $self->stringify_value($value) . "\n";
}
#pod =head2 stringify_value
#pod
#pod my $string = $writer->stringify_value($value);
#pod
#pod This method returns the string that will represent the given value in a
#pod property assignment.
#pod
#pod =cut
sub stringify_value {
my ($self, $value) = @_;
$value = defined $value ? $value : '';
return $value;
}
#pod =head2 stringify_section_header
#pod
#pod my $string = $writer->stringify_section_header($section_name);
#pod
#pod This method returns the string (a line) that represents the given section name.
#pod Basically, this returns:
#pod
#pod [section_name]
#pod
#pod =cut
sub stringify_section_header {
my ($self, $section_name) = @_;
my $output = '';
$output .= "\n" if $self->done_sections;
$output .= "[$section_name]\n";
return $output;
}
#pod =head2 starting_section
#pod
#pod This method returns the name of the starting section. If this section appears
#pod first (as it will, when given a hashref as input) and if
#pod C<L</explicit_starting_header>> returns false, its section header can be
#pod omitted.
#pod
#pod =cut
sub starting_section { return '_' }
#pod =head2 explicit_starting_header
#pod
#pod If this method returns true (which it does I<not>, by default), then the
#pod section header for the starting section will be emitted, even if it appears
#pod first.
#pod
#pod =cut
sub explicit_starting_header { 0 }
#pod =head2 new
#pod
#pod
#pod my $reader = Config::INI::Writer->new;
#pod
#pod This method returns a new writer. This generally does not need to be called by
#pod anything but the various C<write_*> methods, which create a writer object only
#pod ephemerally.
#pod
#pod =cut
sub new {
my ($class) = @_;
my $self = bless { did_section => {} } => $class;
return $self;
}
1;
__END__
=pod
=encoding UTF-8
=head1 NAME
Config::INI::Writer - a subclassable .ini-file emitter
=head1 VERSION
version 0.024
=head1 SYNOPSIS
If <$hash> contains:
{
'_' => { admin => 'rjbs' },
rjbs => {
awesome => 'yes',
height => q{5' 10"},
},
mj => {
awesome => 'totally',
height => '23"',
},
}
Then when your program contains:
Config::INI::Writer->write_file($hash, 'family.ini');
F<family.ini> will contains:
admin = rjbs
[rjbs]
awesome = yes
height = 5' 10"
[mj]
awesome = totally
height = 23"
=head1 DESCRIPTION
Config::INI::Writer is I<yet another> config module implementing I<yet another>
slightly different take on the undeniably easy to read L<".ini" file
format|Config::INI>. Its default behavior is quite similar to that of
L<Config::Tiny>, on which it is based.
The chief difference is that Config::INI::Writer is designed to be subclassed
to allow for side-effects and self-reconfiguration to occur during the course
of reading its input.
=head1 METHODS FOR WRITING CONFIG
There are three writer methods, C<write_string>, C<write_file>, and
C<write_handle>. The first two are implemented in terms of the third. It
iterates over a collection of data, emitting lines to the filehandle as it
goes. The lines are generated by events produced by iterating over the data.
Those events are detailed below in the L</METHODS FOR SUBCLASSING> section.
The given data should be a hashref of hashrefs:
{
section_name_1 => { prop1 => 'value1', prop2 => 'value2' },
section_name_2 => ...
}
...or an arrayref of section name and arrayref pairs:
[
section_name_1 => [ prop1 => 'value1', prop2 => 'value2' ],
section_name_2 => ...
]
...or a combination of those:
[
section_name_1 => { prop1 => 'value1', prop2 => 'value2' },
section_name_2 => [ prop3 => 'value3', prop4 => 'value4' ],
section_name_3 => ...
]
All the reader methods throw an exception when they encounter an error.
=head2 write_file
Config::INI::Writer->write_file($input, $filename);
This method writes out the configuration represented by C<$data> to the file
named by C<$filename>. If a file by that name exists, it is overwritten.
This method will either succeed or raise an exception. (Its return value is
not defined.)
=head2 write_string
my $string = Config::INI::Writer->write_string($input);
This method returns a string containing the INI content describing the given
data.
=head2 write_handle
Config::INI::Writer->write_handle($input, $handle);
This method writes the data in C<$data> to the IO::Handle-like object in
C<$handle>. This method should either succeed or throw an exception.
=head1 METHODS FOR SUBCLASSING
These are the methods you need to understand and possibly change when
subclassing Config::INI::Reader to handle a different format of input.
=head2 preprocess_input
my $processed_input = $writer->preprocess_input($input_data);
This method is called to ensure that the data given to the C<write_*> methods
are in a canonical form for processing and emitting. The default
implementation converts hashrefs to arrayrefs and, if the input is a hashref,
moves the L</starting_section> to the beginning of the produced arrayref.
In other words, given:
{
section_1 => { a => 1, b => 2 },
section_2 => { c => 3, c => 4 },
_ => { d => 5, e => 6 },
}
This method will return:
[
_ => [ d => 5, e => 6 ],
section_2 => [ c => 3, c => 4 ],
section_1 => [ a => 1, b => 2 ],
]
The only guaranteed ordering when hashes are provided as input is that the
starting section will appear first.
=head2 validate_section_name
Carp::croak "section name contains illegal character"
if not $writer->is_valid_section_name($name);
=head2 is_valid_property_name
Carp::croak "property name contains illegal character"
if not $writer->is_valid_property_name($name);
=head2 is_valid_value
Carp::croak "value contains illegal character"
if not $writer->is_valid_value($name);
=head2 validate_input
$writer->validate_input($input);
This method is called on the input data once they've been preprocessed by
C<L</preprocess_input>>.
It ensures that the processed input is structurally sound before beginning to
output it. For example, it ensures that no property is ever assigned more than
once in a given section.
This method either raises an exception or it doesn't.
=head2 change_section
$writer->change_section($section_name);
This method is called each time a new section is going to be written out. If
the same section appears twice in a row in the input, this method will still be
called between instances of that section.
In other words, given this input:
[
section_1 => [ a => 1 ],
section_1 => [ b => 2 ],
]
C<change_section> will be called twice: once before the first C<section_1> and
once before the second C<section_1>.
=head2 current_section
$writer->current_section
This method returns the section currently being written out.
=head2 finish_section
$writer->finish_section
This method is called after all of the current section's properties have been
written.
=head2 done_sections
my @names = $writer->done_sections;
This method returns a list of all sections that have been written out and
finished. The fact that a section name is returned by C<done_sections> does
not mean that there will be no more data for that section, but that at least
one entire set of data has been written out for it.
=head2 stringify_section
my $string = $writer->stringify_section($props);
This method returns a string assigning all the properties set in the given
data. This still will include the section header, if needed. (The only case
in which it is not needed is when the C<L</explicit_starting_header>> method
returns false, no other sections have been done, and the section about to be
stringified is the C<L</starting_section>>.
This method is implemented in terms of C<L</stringify_section_header>> and
C<L</stringify_section_data>>.
=head2 stringify_section_data
my $string = $writer->stringify_section_data($props)
This method returns a string containing a series of lines, each containing a
value assignment for the given properties.
=head2 stringify_value_assignment
my $string = $writer->stringify_value_assignment($name => $value);
This method returns a string that assigns a value to a named property. If the
value is undefined, an empty string is returned.
=head2 stringify_value
my $string = $writer->stringify_value($value);
This method returns the string that will represent the given value in a
property assignment.
=head2 stringify_section_header
my $string = $writer->stringify_section_header($section_name);
This method returns the string (a line) that represents the given section name.
Basically, this returns:
[section_name]
=head2 starting_section
This method returns the name of the starting section. If this section appears
first (as it will, when given a hashref as input) and if
C<L</explicit_starting_header>> returns false, its section header can be
omitted.
=head2 explicit_starting_header
If this method returns true (which it does I<not>, by default), then the
section header for the starting section will be emitted, even if it appears
first.
=head2 new
my $reader = Config::INI::Writer->new;
This method returns a new writer. This generally does not need to be called by
anything but the various C<write_*> methods, which create a writer object only
ephemerally.
=head1 AUTHOR
Ricardo Signes <rjbs@cpan.org>
=head1 COPYRIGHT AND LICENSE
This software is copyright (c) 2007 by Ricardo Signes.
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