NAME
Config::IOD::Reader - Read IOD/INI configuration files
VERSION
This document describes version 0.344 of Config::IOD::Reader (from Perl
distribution Config-IOD-Reader), released on 2022-05-02.
SYNOPSIS
use Config::IOD::Reader;
my $reader = Config::IOD::Reader->new(
# list of known attributes, with their default values
# default_section => 'GLOBAL',
# enable_directive => 1,
# enable_encoding => 1,
# enable_quoting => 1,
# enable_backet => 1,
# enable_brace => 1,
# allow_encodings => undef, # or ['base64','json',...]
# disallow_encodings => undef, # or ['base64','json',...]
# allow_directives => undef, # or ['include','merge',...]
# disallow_directives => undef, # or ['include','merge',...]
# allow_bang_only => 1,
# enable_expr => 0,
# allow_duplicate_key => 1,
# ignore_unknown_directive => 0,
);
my $config_hash = $reader->read_file('config.iod');
DESCRIPTION
This module reads IOD configuration files (IOD is an INI-like format
with more precise specification, some extra features, and 99% compatible
with typical INI format). It is a minimalist alternative to the more
fully-featured Config::IOD. It cannot write IOD files and is optimized
for low startup overhead.
EXPRESSION
Expression allows you to do things like:
[section1]
foo=1
bar="monkey"
[section2]
baz =!e 1+1
qux =!e "grease" . val("section1.bar")
quux=!e val("qux") . " " . val('baz')
And the result will be:
{
section1 => {foo=>1, bar=>"monkey"},
section2 => {baz=>2, qux=>"greasemonkey", quux=>"greasemonkey 2"},
}
For safety, you'll need to set "enable_expr" attribute to 1 first to
enable this feature.
The syntax of the expression (the "expr" encoding) is not officially
specified yet in the IOD specification. It will probably be Expr (see
Language::Expr::Manual::Syntax). At the moment, this module implements a
very limited subset that is compatible (lowest common denominator) with
Perl syntax and uses "eval()" to evaluate the expression. However, only
the limited subset is allowed (checked by Perl 5.10 regular expression).
The supported terms:
number
string (double-quoted and single-quoted)
undef literal
simple variable ($abc, no namespace, no array/hash sigil, no special variables)
function call (only the 'val' function is supported)
grouping (parenthesis)
The supported operators are:
+ - .
* / % x
**
unary -, unary +, !, ~
The "val()" function refers to the configuration key. If the argument
contains ".", it will be assumed as "SECTIONNAME.KEYNAME", otherwise it
will access the current section's key. Since parsing is done in a single
pass, you can only refer to the already mentioned key.
Code will be compiled using Perl's "eval()" in the
"Config::IOD::Expr::_Compiled" namespace, with "no strict", "no
warnings".
ATTRIBUTES
default_section => str (default: "GLOBAL")
If a key line is specified before any section line, this is the section
that the key will be put in.
enable_directive => bool (default: 1)
If set to false, then directives will not be parsed. Lines such as below
will be considered a regular comment:
;!include foo.ini
and lines such as below will be considered a syntax error (regardless of
the "allow_bang_only" setting):
!include foo.ini
NOTE: Turning this setting off violates IOD specification.
enable_encoding => bool (default: 1)
If set to false, then encoding notation will be ignored and key value
will be parsed as verbatim. Example:
name = !json null
With "enable_encoding" turned off, value will not be undef but will be
string with the value of (as Perl literal) "!json null".
NOTE: Turning this setting off violates IOD specification.
enable_quoting => bool (default: 1)
If set to false, then quotes on key value will be ignored and key value
will be parsed as verbatim. Example:
name = "line 1\nline2"
With "enable_quoting" turned off, value will not be a two-line string,
but will be a one line string with the value of (as Perl literal) "line
1\\nline2".
NOTE: Turning this setting off violates IOD specification.
enable_bracket => bool (default: 1)
If set to false, then JSON literal array will be parsed as verbatim.
Example:
name = [1,2,3]
With "enable_bracket" turned off, value will not be a three-element
array, but will be a string with the value of (as Perl literal)
"[1,2,3]".
NOTE: Turning this setting off violates IOD specification.
enable_brace => bool (default: 1)
If set to false, then JSON literal object (hash) will be parsed as
verbatim. Example:
name = {"a":1,"b":2}
With "enable_brace" turned off, value will not be a hash with two pairs,
but will be a string with the value of (as Perl literal)
'{"a":1,"b":2}'.
NOTE: Turning this setting off violates IOD specification.
enable_tilde => bool (default: 1)
If set to true (the default), then value that starts with "~" (tilde)
will be assumed to use !path encoding, unless an explicit encoding has
been otherwise specified.
Example:
log_dir = ~/logs ; ~ will be resolved to current user's home directory
With "enable_tilde" turned off, value will still be literally "~/logs".
NOTE: Turning this setting off violates IOD specification.
allow_encodings => array
If defined, set list of allowed encodings. Note that if
"disallow_encodings" is also set, an encoding must also not be in that
list.
Also note that, for safety reason, if you want to enable "expr"
encoding, you'll also need to set "enable_expr" to 1.
disallow_encodings => array
If defined, set list of disallowed encodings. Note that if
"allow_encodings" is also set, an encoding must also be in that list.
Also note that, for safety reason, if you want to enable "expr"
encoding, you'll also need to set "enable_expr" to 1.
enable_expr => bool (default: 0)
Whether to enable "expr" encoding. By default this is turned off, for
safety. Please see "EXPRESSION" for more details.
allow_directives => array
If defined, only directives listed here are allowed. Note that if
"disallow_directives" is also set, a directive must also not be in that
list.
disallow_directives => array
If defined, directives listed here are not allowed. Note that if
"allow_directives" is also set, a directive must also be in that list.
allow_bang_only => bool (default: 1)
Since the mistake of specifying a directive like this:
!foo
instead of the correct:
;!foo
is very common, the spec allows it. This reader, however, can be
configured to be more strict.
allow_duplicate_key => bool (default: 1)
If set to 0, you can forbid duplicate key, e.g.:
[section]
a=1
a=2
or:
[section]
a=1
b=2
c=3
a=10
In traditional INI file, to specify an array you specify multiple keys.
But when there is only a single key, it is unclear if the value is a
single-element array or a scalar. You can use this setting to avoid this
array/scalar ambiguity in config file and force user to use JSON
encoding or bracket to specify array:
[section]
a=[1,2]
NOTE: Turning this setting off violates IOD specification.
ignore_unknown_directive => bool (default: 0)
If set to true, will not die if an unknown directive is encountered. It
will simply be ignored as a regular comment.
NOTE: Turning this setting on violates IOD specification.
warn_perl => bool (default: 0)
Emit warning if configuration contains key line like these:
foo=>"bar"
foo => bar,
which suggest user is assuming configuration is in Perl format instead
of INI.
METHODS
new(%attrs) => obj
$reader->read_file($filename[ , $callback ]) => hash
Read IOD configuration from a file. Die on errors.
See "read_string" for more information on $callback argument.
$reader->read_string($str[ , $callback ]) => hash
Read IOD configuration from a string. Die on errors.
$callback is an optional coderef argument that will be called during
various stages. It can be useful if you want more information
(especially ordering). It will be called with hash argument %args
* Found a directive line
Arguments passed: "event" (str, has the value of 'directive'),
"linum" (int, line number, starts from 1), "line" (str, raw line),
"directive" (str, directive name), "cur_section" (str, current
section name), "args" (array, directive arguments).
* Found a comment line
Arguments passed: "event" (str, 'comment'), "linum", "line",
"cur_section".
* Found a section line
Arguments passed: "event" (str, 'section'), "linum", "line",
"cur_section", "section" (str, section name).
* Found a key line
Arguments passed: "event" (str, 'section'), "linum", "line",
"cur_section", "key" (str, key name), "val" (any, value name,
already decoded if encoded), "raw_val" (str, raw value).
TODO: callback when there is merging.
HOMEPAGE
Please visit the project's homepage at
<https://metacpan.org/release/Config-IOD-Reader>.
SOURCE
Source repository is at
<https://github.com/perlancar/perl-Config-IOD-Reader>.
SEE ALSO
IOD - specification
Config::IOD - round-trip parser for reading as well as writing IOD
documents
IOD::Examples - sample documents
AUTHOR
perlancar <perlancar@cpan.org>
CONTRIBUTOR
Steven Haryanto <stevenharyanto@gmail.com>
CONTRIBUTING
To contribute, you can send patches by email/via RT, or send pull
requests on GitHub.
Most of the time, you don't need to build the distribution yourself. You
can simply modify the code, then test via:
% prove -l
If you want to build the distribution (e.g. to try to install it locally
on your system), you can install Dist::Zilla,
Dist::Zilla::PluginBundle::Author::PERLANCAR, and sometimes one or two
other Dist::Zilla plugin and/or Pod::Weaver::Plugin. Any additional
steps required beyond that are considered a bug and can be reported to
me.
COPYRIGHT AND LICENSE
This software is copyright (c) 2022, 2021, 2019, 2018, 2017, 2016, 2015,
2014 by perlancar <perlancar@cpan.org>.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.
BUGS
Please report any bugs or feature requests on the bugtracker website
<https://rt.cpan.org/Public/Dist/Display.html?Name=Config-IOD-Reader>
When submitting a bug or request, please include a test-file or a patch
to an existing test-file that illustrates the bug or desired feature.
