JSON::Schema::Modern::Result(3pm)

NAME
JSON::Schema::Modern::Result - Contains the result of a JSON Schema evaluation

VERSION
version 0.641

SYNOPSIS
  use JSON::Schema::Modern;
  my $js = JSON::Schema::Modern->new;
  my $result = $js->evaluate($data, $schema);
  my @errors = $result->errors;

  my $result_data_encoded = encode_json($result); # calls TO_JSON

  # use in numeric and boolean context
  say sprintf('got %d %ss', $result, ($result->valid ? 'annotation' : 'error'));

  # use in string context
  say 'full results: ', $result;

  # combine two results into one:
  my $overall_result = $result1 & $result2;

DESCRIPTION
This object holds the complete results of evaluating a data payload against a JSON Schema using JSON::Schema::Modern.

OVERLOADS
The object contains a string overload, which evaluates to a potentially multi-line string summarizing the errors within (if any); this is intended to be used as a user-oriented error message that references data locations, but not schema locations.

The object also contains a bitwise AND overload ("&"), for combining two results into one (the result is valid iff both inputs are valid; annotations and errors from the second argument are appended to those of the first in a new Result object).

CONSTRUCTOR ARGUMENTS
Unless otherwise noted, these are also available as read-only accessors.

  valid
A boolean. Indicates whether validation was successful or failed.

Optional, as it can be calculated from the presence of "errors" or "annotations".

  errors
An array of JSON::Schema::Modern::Error objects.

  annotations
An array of JSON::Schema::Modern::Annotation objects.

  output_format
Also available as a read/write accessor.

One of: "flag", "basic", "strict_basic", "terse", "data_only". Defaults to "basic".

•   "flag" returns just the result of the evaluation: either "{"valid": true}" or "{"valid": false}".

•   "basic" adds the list of "errors" or "annotations" to the boolean evaluation result. "instance_location" and "keyword_location" are always included, as JSON pointers, describing the path to the evaluation location; "absolute_keyword_location" is added (as a resolved URI) whenever it is known and different from "keyword_location".

•   "strict_basic" is like "basic" but follows the draft-2019-09 specification precisely, including replicating an error fixed in the next draft, in that "instance_location" and "keyword_location" values are provided as fragment-only URI references rather than JSON pointers.

•   "terse" is not described in any specification; it is like "basic", but omits some redundant errors (for example the one for the "allOf" keyword that is added when any of the subschemas under "allOf" failed evaluation).

•   "data_only" returns a string, not a data structure: it contains a list of errors identified only by their "instance_location" and error message (or "keyword_location", when the error occurred while loading the schema itself). This format is suitable for generating errors when the schema is not published, or for describing errors with the schema itself. This is not an official specification format and may change slightly over time, as it is tested in production environments.

  formatted_annotations
A boolean flag indicating whether "format" should include annotations in the output. Defaults to true.

  exception
Indicates that evaluation stopped due to a severe error.

  recommended_response
A tuple, consisting of "[ integer, string ]", indicating the recommended HTTP response code and string to use for this result (if validating an HTTP request). This could exist for things like a failed authentication check in OpenAPI validation, in which case it would contain "[ 401, 'Unauthorized' ]".

Only populated when there are errors; when not explicitly set by an evaluator, defaults to "[ 500, 'Internal Server Error' ]" if any errors indicate an exception, and "[ 400, <first error string> ]" otherwise. The exact error string is hidden in the case of 500 errors because you should not leak internal issues with your application, but you may also wish to obfuscate normal validation errors, in which case you should check for 400 and change the string to 'Bad Request'.

Also available as a read/write accessor.

  defaults
A hashref, mapping json pointer locations in the instance data to the default value assigned to the property at this location, taken from "default" keywords in the schema under "properties" and "patternProperties" keywords (requires the "defaults" in JSON::Schema::Modern configuration to be enabled). This data will also be included in the "basic" output format when it is defined.

  data
Contains a cloned copy of the instance data that was evaluated; includes decoded values from "contentEncoding" and "contentMediaType" keywords, and is also populated with defaults if "defaults" is set (via "with_defaults" in JSON::Schema::Modern).

In results coming from OpenAPI::Modern, this value may contain deserialized data from various parts of the HTTP message, such as path and query parameters, header values, and the deserialized message body. Refer to that documentation for more details.

METHODS

  format
Returns a data structure suitable for serialization; requires one argument specifying the output format to use, which corresponds to the formats documented in <https://json-schema.org/draft/2019-09/json-schema-core.html#rfc.section.10.4>. The only supported formats at this time are "flag", "basic", "strict_basic", and "terse".

  TO_JSON
Calls "format" with the style configured in "output_format".

  count
Returns the number of annotations when the result is true, or the number of errors when the result is false.

  combine
When provided with another result object, returns a new object with the combination of all results. See "&" at "OVERLOADS".

  dump
Returns a JSON string representing the result object, using the requested "format", according to the draft2019-09 specification <https://json-schema.org/draft/2019-09/json-schema-core.html#rfc.section.10> and the draft2020-12 specification <https://json-schema.org/draft/2020-12/json-schema-core#section-12>.

SERIALIZATION
Results (and their contained errors and annotations) can be serialized in a number of ways.

Results have defined "output_format"s, which can be generated as nested unblessed hashes/arrays and are suitable for serializing using a JSON encoder for use in another application. A JSON string of the result can be obtained directly using "dump".

If it is preferable to omit direct references to the schema (for example in an application where the schema is not published), but still convey some semantic information about the nature of the errors, stringify the object directly. This also means that result objects can be thrown as exceptions, or embedded in error messages.

If you are embedding the full result inside another data structure, perhaps to be serialized to JSON (or another format) later on, use "TO_JSON" or "format".

GIVING THANKS
If you found this module to be useful, please show your appreciation by adding a +1 in MetaCPAN <https://metacpan.org/dist/JSON-Schema-Modern> and a star in GitHub <https://github.com/karenetheridge/JSON-Schema-Modern>.

SUPPORT
Bugs may be submitted through <https://github.com/karenetheridge/JSON-Schema-Modern/issues>.

I am also usually active on irc, as 'ether' at "irc.perl.org" and "irc.libera.chat".

You can also find me on the JSON Schema Slack server <https://json-schema.slack.com> and OpenAPI Slack server <https://open-api.slack.com>, which are also great resources for finding help.

AUTHOR
Karen Etheridge <ether@cpan.org>

COPYRIGHT AND LICENCE
This software is copyright (c) 2020 by Karen Etheridge.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.

Some schema files have their own licence, in share/LICENSE.