JSON::Validator - Validate data against a JSON schema
0.87
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;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 can be used standalone, but if you want to define a specification for your webserver's API, then have a look at Mojolicious::Plugin::OpenAPI, which will replace Mojolicious::Plugin::Swagger2.
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. The order is set by which module that performs the best, so it might change in the future.
Here are some resources that are related to JSON schemas and validation:
This module comes with some JSON specifications bundled, so your application don't have to fetch those from the web. These specifications should be up to date, but please submit an issue if they are not.
Note that the bundled specifications can be ignored, by customizing "cache_paths".
JSON schema, draft 4
Web page: http://json-schema.org
JSON schema for JSONPatch files
Web page: http://jsonpatch.com
Swagger / OpenAPI specification, version 2
Web page: https://openapis.org
Custom error document
There is a custom schema used by Mojolicious::Plugin::OpenAPI as a default error document. This document might be extended later, but it will always be backward compatible.
Specification: https://github.com/jhthorsen/json-validator/blob/master/lib/JSON/Validator/cache/630949337805585c8e52deea27d11419
$ref: http://git.io/vcKD4#.Swagger Petstore
This is used for unit tests, and should probably not be relied on by external users.
The method "validate" and the function "validate_json" returns error objects when the input data violates the "schema". Each of the objects looks like this:
bless {
message => "Some description",
path => "/json/path/to/node",
}, "JSON::Validator::Error"See also JSON::Validator::Error.
The error object overloads the following operators:
bool
Returns a true value.
string
Returns the "path" and "message" part as a string: "$path: $message".
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 => "(String is too long: 8/5. String is too short: 8/12)",
path => "/json/path/to/node",
}, "JSON::Validator::Error"Note that these error messages are subject for change. Any suggestions are most welcome!
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.
Deprecated in favor of "cache_paths".
$self = $self->cache_paths(\@paths);
$array_ref = $self->cache_paths;Search paths to where cached specifications are stored. Defaults to JSON_VALIDATOR_CACHE_DIR and the bundled spec files that are shipped with this distribution.
JSON_VALIDATOR_CACHE_DIR=/cache/dir:/some/other/location perl script.plTo download a file and add it to the cache, do this:
$ curl http://swagger.io/v2/schema.json > /cache/dir/$(md5 -qs http://swagger.io/v2/schema.json)Files referenced to an URL will automatically be cached if the first path in "cache_paths" is writable.
$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.
regex
EXPERIMENTAL. Will check if the string is a regex, using
qr{...}.uri
Validated against the RFC3986 spec.
$code = $self->resolver;
$self = $self->resolver(sub { my ($self, $namespace, $refs) = @_; });Set this to a sub without any logic if you want to skip resolving references, like this:
$self->resolver(sub {});This attribute is EXPERIMENTAL.
$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)
$self = $self->coerce(booleans => 1, numbers => 1, strings => 1);
$self = $self->coerce({booleans => 1, numbers => 1, strings => 1});
$self = $self->coerce(1) # enable all
$hash = $self->coerce;Set the given type to coerce. Before enabling coercion this module is very strict when it comes to validating types. Example: The string "1" is not the same as the number 1, unless you have coercion enabled.
WARNING! Enabling coercion might hide bugs in your api, which would have been detected if you were strict. For example JavaScript is very picky on a number being an actual number. This module tries it best to convert the data on the fly into the proper value, but this means that you unit tests might be ok, but the client side libraries (that care about types) might break.
Loading a YAML document will enable "booleans" automatically. This feature is experimental, but was added since YAML has no real concept of booleans, such as Mojo::JSON or other JSON parsers.
The coercion rules are EXPERIMENTAL and will be tighten/loosen if bugs are reported. See jhthorsen#8 for more details.
$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.
$self = $class->singleton;Returns the JSON::Validator object used by "validate_json".
@errors = $self->validate($data);
@errors = $self->validate($data, $schema);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.
$schema is optional, but when specified, it will override schema stored in "schema". Example:
$self->validate({hero => "superwoman"}, {type => "object"});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.
Jan Henning Thorsen - [email protected]