Sah-Schemas-JSON/lib/Sah/Schema/any_from_json.pm
package Sah::Schema::any_from_json;
use strict;
use warnings;
our $AUTHORITY = 'cpan:PERLANCAR'; # AUTHORITY
our $DATE = '2022-11-15'; # DATE
our $DIST = 'Sah-Schemas-JSON'; # DIST
our $VERSION = '0.007'; # VERSION
our $schema = [any => {
summary => 'A data structure, coerced from JSON string',
'prefilters' => ['JSON::decode_str'],
description => <<'_',
You can use this schema if you want to accept any data (a data structure or
simple scalar), but if user supplies a defined string e.g. in a command-line
script as command-line argument or option, the string will be assumed to be a
JSON-encoded value and decoded. Data will not be valid if the string does not
contain valid JSON.
Thus, if you want to supply a string, you have to JSON-encode it.
_
examples => [
{value=>'', valid=>0, summary=>'Empty string is not a valid JSON'},
{value=>'1', valid=>1, summary=>"A number"},
{value=>'null', valid=>1, validated_value=>undef},
{value=>'foo', valid=>0, summary=>'Not a valid JSON literal, you have to encode string in JSON'},
{value=>'"foo"', valid=>1, validated_value=>'foo', summary=>'If you want to pass a string, it must be in JSON-encoded form'},
{value=>'[1,2,3,{}]', valid=>1, validated_value=>[1,2,3,{}]},
{value=>'[1,2', valid=>0, summary=>'Missing closing square bracket'},
{value=>'[1,2,]', valid=>0, summary=>'Dangling comma'},
{value=>[1,2], valid=>1, summary=>'Not coerced, already an array'},
{value=>{}, valid=>1, summary=>'Not coerced, already a hash'},
{value=>undef, valid=>1, summary=>'Not coerced, already an undef'},
],
}];
1;
# ABSTRACT: A data structure, coerced from JSON string
__END__
=pod
=encoding UTF-8
=head1 NAME
Sah::Schema::any_from_json - A data structure, coerced from JSON string
=head1 VERSION
This document describes version 0.007 of Sah::Schema::any_from_json (from Perl distribution Sah-Schemas-JSON), released on 2022-11-15.
=head1 SYNOPSIS
=head2 Sample data and validation results against this schema
"" # INVALID (Empty string is not a valid JSON)
1 # valid (A number)
"null" # valid, becomes undef
"foo" # INVALID (Not a valid JSON literal, you have to encode string in JSON)
"\"foo\"" # valid (If you want to pass a string, it must be in JSON-encoded form), becomes "foo"
"[1,2,3,{}]" # valid, becomes [1,2,3,{}]
"[1,2" # INVALID (Missing closing square bracket)
"[1,2,]" # INVALID (Dangling comma)
[1,2] # valid (Not coerced, already an array)
{} # valid (Not coerced, already a hash)
undef # valid (Not coerced, already an undef)
=head2 Using with Data::Sah
To check data against this schema (requires L<Data::Sah>):
use Data::Sah qw(gen_validator);
my $validator = gen_validator("any_from_json*");
say $validator->($data) ? "valid" : "INVALID!";
The above schema returns a boolean result (true if data is valid, false if
otherwise). To return an error message string instead (empty string if data is
valid, a non-empty error message otherwise):
my $validator = gen_validator("any_from_json", {return_type=>'str_errmsg'});
my $errmsg = $validator->($data);
# a sample valid data
$data = [1,2];
my $errmsg = $validator->($data); # => ""
# a sample invalid data
$data = "[1,2";
my $errmsg = $validator->($data); # => "String is not a valid JSON: , or ] expected while parsing array, at character offset 4 (before \"(end of string)\") at (eval 2418) line 13.\n"
Often a schema has coercion rule or default value, so after validation the
validated value is different. To return the validated (set-as-default, coerced,
prefiltered) value:
my $validator = gen_validator("any_from_json", {return_type=>'str_errmsg+val'});
my $res = $validator->($data); # [$errmsg, $validated_val]
# a sample valid data
$data = [1,2];
my $res = $validator->($data); # => ["",[1,2]]
# a sample invalid data
$data = "[1,2";
my $res = $validator->($data); # => ["String is not a valid JSON: , or ] expected while parsing array, at character offset 4 (before \"(end of string)\") at (eval 2424) line 13.\n","[1,2"]
Data::Sah can also create validator that returns a hash of detailed error
message. Data::Sah can even create validator that targets other language, like
JavaScript, from the same schema. Other things Data::Sah can do: show source
code for validator, generate a validator code with debug comments and/or log
statements, generate human text from schema. See its documentation for more
details.
=head2 Using with Params::Sah
To validate function parameters against this schema (requires L<Params::Sah>):
use Params::Sah qw(gen_validator);
sub myfunc {
my @args = @_;
state $validator = gen_validator("any_from_json*");
$validator->(\@args);
...
}
=head2 Using with Perinci::CmdLine::Lite
To specify schema in L<Rinci> function metadata and use the metadata with
L<Perinci::CmdLine> (L<Perinci::CmdLine::Lite>) to create a CLI:
# in lib/MyApp.pm
package
MyApp;
our %SPEC;
$SPEC{myfunc} = {
v => 1.1,
summary => 'Routine to do blah ...',
args => {
arg1 => {
summary => 'The blah blah argument',
schema => ['any_from_json*'],
},
...
},
};
sub myfunc {
my %args = @_;
...
}
1;
# in myapp.pl
package
main;
use Perinci::CmdLine::Any;
Perinci::CmdLine::Any->new(url=>'/MyApp/myfunc')->run;
# in command-line
% ./myapp.pl --help
myapp - Routine to do blah ...
...
% ./myapp.pl --version
% ./myapp.pl --arg1 ...
=head2 Using with Type::Tiny
To create a type constraint and type library from a schema:
package My::Types {
use Type::Library -base;
use Type::FromSah qw( sah2type );
__PACKAGE__->add_type(
sah2type('$sch_name*', name=>'AnyFromJson')
);
}
use My::Types qw(AnyFromJson);
AnyFromJson->assert_valid($data);
=head1 DESCRIPTION
You can use this schema if you want to accept any data (a data structure or
simple scalar), but if user supplies a defined string e.g. in a command-line
script as command-line argument or option, the string will be assumed to be a
JSON-encoded value and decoded. Data will not be valid if the string does not
contain valid JSON.
Thus, if you want to supply a string, you have to JSON-encode it.
=head1 HOMEPAGE
Please visit the project's homepage at L<https://metacpan.org/release/Sah-Schemas-JSON>.
=head1 SOURCE
Source repository is at L<https://github.com/perlancar/perl-Sah-Schemas-JSON>.
=head1 AUTHOR
perlancar <perlancar@cpan.org>
=head1 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 L<Dist::Zilla>,
L<Dist::Zilla::PluginBundle::Author::PERLANCAR>,
L<Pod::Weaver::PluginBundle::Author::PERLANCAR>, and sometimes one or two other
Dist::Zilla- and/or Pod::Weaver plugins. Any additional steps required beyond
that are considered a bug and can be reported to me.
=head1 COPYRIGHT AND LICENSE
This software is copyright (c) 2022, 2021 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.
=head1 BUGS
Please report any bugs or feature requests on the bugtracker website L<https://rt.cpan.org/Public/Dist/Display.html?Name=Sah-Schemas-JSON>
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.
=cut