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JSON-Validator-0.55
River stage two • 16 direct dependents • 26 total dependents
35 ++
/ JSON::Validator

NAME

JSON::Validator - Validate data against a JSON schema

VERSION

0.55

SYNOPSIS

  use JSON::Validator;
  my $validator = JSON::Validator->new;

  # Define a schema - http://json-schema.org/examples.html
  # You can also load schema from disk or web
  $validator->schema(
    {
      type       => "object",
      required   => ["firstName", "lastName"],
      properties => {
        firstName => {type => "string"},
        lastName  => {type => "string"},
        age       => {type => "integer", minimum => 0, description => "Age in years"}
      }
    }
  );

  # Validate your data
  @errors = $validator->validate({firstName => "Jan Henning", lastName => "Thorsen", age => -42});

  # Do something if any errors was found
  die "@errors" if @errors;

DESCRIPTION

JSON::Validator is a class for validating data against JSON schemas. You might want to use this instead of JSON::Schema if you need to validate data against draft 4 of the specification.

This module is currently EXPERIMENTAL. Hopefully nothing drastic will change, but it needs to fit together nicely with Swagger2 - Since this is a spin-off project.

Supported schema formats

JSON::Validator can load JSON schemas in multiple formats: Plain perl data structured (as shown in "SYNOPSIS") or files on disk/web in the JSON/YAML format. The JSON parsing is done using Mojo::JSON, while the YAML parsing is done with an optional modules which need to be installed manually. JSON::Validator will look for the YAML modules in this order: YAML::XS, YAML::Syck, YAML::Tiny, YAML. The order is set by which module that performs the best, so it might change in the future.

Resources

Here are some resources that are related to JSON schemas and validation:

ERROR OBJECT

Overview

The method "validate" and the function "validate_json" returns error objects when the input data violates the "schema". Each of the objects looks like this:

  bless {
    message => "Some description",
    path => "/json/path/to/node",
  }, "JSON::Validator::Error"

Operators

The error object overloads the following operators:

  • bool

    Returns a true value.

  • string

    Returns the "path" and "message" part as a string: "$path: $message".

Special cases

Have a look at the test suite for documented examples of the error cases. Especially look at jv-allof.t, jv-anyof.t and jv-oneof.t.

The special cases for "allOf", "anyOf" and "oneOf" will contain the error messages from all the failing rules below. It can be a bit hard to read, so if the error message is long, then you might want to run a smaller test with JSON_VALIDATOR_DEBUG=1.

Example error object:

  bless {
    message => "[0] String is too long: 8/5. [1] Expected number - got string.",
    path => "/json/path/to/node",
  }, "JSON::Validator::Error"

Note that these error messages are subject for change. Any suggestions are most welcome!

FUNCTIONS

validate_json

  use JSON::Validator "validate_json";
  @errors = validate_json $data, $schema;

This can be useful in web applications:

  @errors = validate_json $c->req->json, "data://main/spec.json";

See also "validate" and "ERROR OBJECT" for more details.

ATTRIBUTES

cache_dir

  $self = $self->cache_dir($path);
  $path = $self->cache_dir;

Path to where downloaded spec files should be cached. Defaults to JSON_VALIDATOR_CACHE_DIR or the bundled spec files that are shipped with this distribution.

coerce

  $self = $self->coerce(1);
  $bool = $self->coerce;

Set this to true if you want to coerce numbers into string and the other way around.

This is EXPERIMENTAL and could be removed without notice!

formats

  $hash_ref = $self->formats;
  $self = $self->formats(\%hash);

Holds a hash-ref, where the keys are supported JSON type "formats", and the values holds a code block which can validate a given format.

Note! The modules mentioned below are optional.

  • date-time

    An RFC3339 timestamp in UTC time. This is formatted as "YYYY-MM-DDThh:mm:ss.fffZ". The milliseconds portion (".fff") is optional

  • email

    Validated against the RFC5322 spec.

  • hostname

    Will be validated using Data::Validate::Domain if installed.

  • ipv4

    Will be validated using Data::Validate::IP if installed or fall back to a plain IPv4 IP regex.

  • ipv6

    Will be validated using Data::Validate::IP if installed.

  • uri

    Validated against the RFC3986 spec.

ua

  $ua = $self->ua;
  $self = $self->ua(Mojo::UserAgent->new);

Holds a Mojo::UserAgent object, used by "schema" to load a JSON schema from remote location.

Note that the default Mojo::UserAgent will detect proxy settings and have "max_redirects" in Mojo::UserAgent set to 3. (These settings are EXPERIMENTAL and might change without a warning)

METHODS

schema

  $self = $self->schema(\%schema);
  $self = $self->schema($url);
  $schema = $self->schema;

Used to set a schema from either a data structure or a URL.

$schema will be a Mojo::JSON::Pointer object when loaded, and undef by default.

The $url can take many forms, but needs to point to a text file in the JSON or YAML format.

  • http://... or https://...

    A web resource will be fetched using the Mojo::UserAgent, stored in "ua".

  • data://Some::Module/file.name

    This version will use "data_section" in Mojo::Loader to load "file.name" from the module "Some::Module".

  • /path/to/file

    An URL (without a recognized scheme) will be loaded from disk.

singleton

  $self = $class->singleton;

Returns the JSON::Validator object used by "validate_json".

validate

  @errors = $self->validate($data);

Validates $data against a given JSON "schema". @errors will contain validation error objects or be an empty list on success.

See "ERROR OBJECT" for details.

COPYRIGHT AND LICENSE

Copyright (C) 2014-2015, Jan Henning Thorsen

This program is free software, you can redistribute it and/or modify it under the terms of the Artistic License version 2.0.

AUTHOR

Jan Henning Thorsen - jhthorsen@cpan.org