# NAME
JSON::Pointer - A Perl implementation of JSON Pointer (RFC6901)
# VERSION
This document describes JSON::Pointer version 0.07.
# SYNOPSIS
use JSON::Pointer;
my $obj = {
foo => 1,
bar => [ { qux => "hello" }, 3 ],
baz => { boo => [ 1, 3, 5, 7 ] }
};
JSON::Pointer->get($obj, "/foo"); ### $obj->{foo}
JSON::Pointer->get($obj, "/bar/0"); ### $obj->{bar}[0]
JSON::Pointer->get($obj, "/bar/0/qux"); ### $obj->{bar}[0]{qux}
JSON::Pointer->get($obj, "/bar/1"); ### $obj->{bar}[1]
JSON::Pointer->get($obj, "/baz/boo/2"); ### $obj->{baz}{boo}[2]
# DESCRIPTION
This library is implemented JSON Pointer ([http://tools.ietf.org/html/rfc6901](http://tools.ietf.org/html/rfc6901)) and
some useful operator from JSON Patch ([http://tools.ietf.org/html/rfc6902](http://tools.ietf.org/html/rfc6902)).
JSON Pointer is available to identify a specified value in JSON document, and it is simillar to XPath.
Please read the both of specifications for details.
# METHODS
## get($document :HashRef/ArrayRef/Scalar, $pointer :Str, $strict :Int) :Scalar
- $document :HashRef/ArrayRef/Scalar
Target perl data structure that is able to be presented by JSON format.
- $pointer :Str
JSON Pointer string to identify specified value in the document.
- $strict :Int
Strict mode. When this value equals true value, this method may throw exception on error.
When this value equals false value, this method return undef value on error.
Get specified value identified by _$pointer_ from _$document_.
For example,
use JSON::Pointer;
print JSON::Pointer->get({ foo => 1, bar => { "qux" => "hello" } }, "/bar/qux"); ### hello
## get\_relative($document :HashRef/ArrayRef/Scalar, $current\_pointer :Str, $relative\_pointer :Str, $strict :Int) :Scalar
**This method is highly EXPERIMENTAL**. Because this method depends on [http://tools.ietf.org/html/draft-luff-relative-json-pointer-00](http://tools.ietf.org/html/draft-luff-relative-json-pointer-00) draft spec.
- $document :HashRef/ArrayRef/Scalar
Target perl data structure that is able to be presented by JSON format.
- $current\_pointer : Str
JSON Pointer string to identify specified current position in the document.
- $relative\_pointer : Str
JSON Relative Pointer string to identify specified value from current position in the document
- $strict :Int
Strict mode. When this value equals true value, this method may throw exception on error.
When this value equals false value, this method return undef value on error.
## contains($document :HashRef/ArrayRef/Scalar, $pointer :Str) :Int
- $document :HashRef/ArrayRef/Scalar
Target perl data structure that is able to present by JSON format.
- $pointer :Str
JSON Pointer string to identify specified value in the document.
Return which the target location identified by _$pointer_ exists or not in the _$document_.
use JSON::Pointer;
my $document = { foo => 1 };
if (JSON::Pointer->contains($document, "/foo")) {
print "/foo exists";
}
## add($document :HashRef/ArrayRef/Scalar, $pointer :Str, $value :HashRef/ArrayRef/Scalar) :HashRef/ArrayRef/Scalar
- $document :HashRef/ArrayRef/Scalar
Target perl data structure that is able to be presented by JSON format.
- $pointer :Str
JSON Pointer string to identify specified value in the document.
- $value :HashRef/ArrayRef/Scalar
The perl data structure that is able to be presented by JSON format.
Add specified _$value_ on target location identified by _$pointer_ in the _$document_.
For example,
use JSON::Pointer;
my $document = +{ foo => 1, };
my $value = +{ qux => "hello" };
my $patched_document = JSON::Pointer->add($document, "/bar", $value);
print $patched_document->{bar}{qux}; ### hello
## remove($document, $pointer) :Array/Scalar
- $document :HashRef/ArrayRef/Scalar
Target perl data structure that is able to be presented by JSON format.
- $pointer :Str
JSON Pointer string to identify specified value in the document.
Remove target location identified by _$pointer_ in the _$document_.
use JSON::Pointer;
my $document = { foo => 1 };
my $patched_document = JSON::Pointer->remove($document, "/foo");
unless (exists $patched_document->{foo}) {
print "removed /foo";
}
This method is contextial return value. When the return value of _wantarray_ equals true,
return _$patched\_document_ and _$removed\_value_, or not return _$patched\_document_ only.
## replace($document :HashRef/ArrayRef/Scalar, $pointer :Str, $value :HashRef/ArrayRef/Scalar) :Array/HashRef/ArrayRef/Scalar
- $document :HashRef/ArrayRef/Scalar
Target perl data structure that is able to be presented by JSON format.
- $pointer :Str
JSON Pointer string to identify specified value in the document.
- $value :HashRef/ArrayRef/Scalar
The perl data structure that is able to be presented by JSON format.
Replace the value of target location specified by _$pointer_ to the _$value_ in the _$document_.
use JSON::Pointer;
my $document = { foo => 1 };
my $patched_document = JSON::Pointer->replace($document, "/foo", 2);
print $patched_document->{foo}; ## 2
This method is contextial return value. When the return value of _wantarray_ equals true,
return _$patched\_document_ and _$replaced\_value_, or not return _$patched\_document_ only.
## set($document :HashRef/ArrayRef/Scalar, $pointer :Str, $value :HashRef/ArrayRef/Scalar) :Array/HashRef/ArrayRef/Scalar
This method is alias of replace method.
## copy($document :HashRef/ArrayRef/Scalar, $from\_pointer :Str, $to\_pointer :Str) :HashRef/ArrayRef/Scalar
- $document :HashRef/ArrayRef/Scalar
Target perl data structure that is able to be presented by JSON format.
- $from\_pointer :Str
JSON Pointer string to identify specified value in the document.
- $to\_pointer :Str
JSON Pointer string to identify specified value in the document.
Copy the value identified by _$from\_pointer_ to target location identified by _$to\_pointer_.
For example,
use JSON::Pointer;
my $document = +{ foo => [ { qux => "hello" } ], bar => [ 1 ] };
my $patched_document = JSON::Pointer->copy($document, "/foo/0/qux", "/bar/-");
print $patched_document->{bar}[1]; ## hello
Note that "-" notation means next of last element in the array.
In this example, "-" means 1.
## move($document :HashRef/ArrayRef/Scalar, $from\_pointer :Str, $to\_pointer :Str) :HashRef/ArrayRef/Scalar
- $document :HashRef/ArrayRef/Scalar
Target perl data structure that is able to be presented by JSON format.
- $from\_pointer :Str
JSON Pointer string to identify specified value in the document.
- $to\_pointer :Str
JSON Pointer string to identify specified value in the document.
Move the value identified by _$from\_pointer_ to target location identified by _$to\_pointer_.
For example,
use JSON;
use JSON::Pointer;
my $document = +{ foo => [ { qux => "hello" } ], bar => [ 1 ] };
my $patched_document = JSON::Pointer->move($document, "/foo/0/qux", "/bar/-");
print encode_json($patched_document); ## {"bar":[1,"hello"],"foo":[{}]}
## test($document :HashRef/ArrayRef/Scalar, $pointer :Str, $value :HashRef/ArrayRef/Scalar) :Int
- $document :HashRef/ArrayRef/Scalar
Target perl data structure that is able to be presented by JSON format.
- $pointer :Str
JSON Pointer string to identify specified value in the document.
- $value :HashRef/ArrayRef/Scalar
The perl data structure that is able to be presented by JSON format.
Return which the value identified by _$pointer_ equals _$value_ or not in the _$document_.
This method distinguish type of each values.
use JSON::Pointer;
my $document = { foo => 1 };
print JSON::Pointer->test($document, "/foo", 1); ### 1
print JSON::Pointer->test($document, "/foo", "1"); ### 0
## traverse($document, $pointer, $opts) : JSON::Pointer::Context
This method is used as internal implementation only.
# DEPENDENCIES
Perl 5.8.1 or later.
# BUGS
All complex software has bugs lurking in it, and this module is no
exception. If you find a bug please either email me, or add the bug
to cpan-RT.
# SEE ALSO
- [perl](https://metacpan.org/pod/perl)
- [Mojo::JSON::Pointer](https://metacpan.org/pod/Mojo::JSON::Pointer)
Many codes in this module is inspired by the module.
- [http://tools.ietf.org/html/rfc6901](http://tools.ietf.org/html/rfc6901)
- [http://tools.ietf.org/html/rfc6902](http://tools.ietf.org/html/rfc6902)
- [http://tools.ietf.org/html/draft-luff-relative-json-pointer-00](http://tools.ietf.org/html/draft-luff-relative-json-pointer-00)
# AUTHOR
Toru Yamaguchi <zigorou at cpan.org>
# LICENSE AND COPYRIGHT
Copyright (c) 2013, Toru Yamaguchi. All rights reserved.
This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.