--- name: "JSON::Pointer" section: "3pm" platform: "linux" package: "libjson-pointer-perl" version: "0.07-2" release: "Debian 13 (Trixie)" platforms: ["linux"] url: "https://new.carta.tech/JSON::Pointer" --- # JSON::Pointer(3pm) A Perl implementation of JSON Pointer (RFC6901) ## 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 (\) and some useful operator from JSON Patch (\). 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 \ 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 - Mojo::JSON::Pointer Many codes in this module is inspired by the module. - \ - \ - \ ## AUTHOR Toru Yamaguchi \ ## 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.