Exonerate

A JSONSchema -> Elixir compiler

Documentation

Documentation is available at: https://hexdocs.pm/exonerate

Performance

Accuracy benchmark relative to GPT-3.5 and GPT-4

Performance (speed) benchmark relative to other elixir JSONSchema libraries

JsonSchema support scope:

Currently supports JSONSchema drafts 4, 6, 7, 2019, 2020. except:

• multipleOf is not supported for number types. This is because elixir does not support a floating point remainder guard, and also because it is impossible for a floating point to guarantee sane results (e.g. for IEEE Float64, 1.2 / 0.1 != 12)

• id fields with fragments in their uri identifier

• dynamicRefs and anchors.

• contentMediaType, contentEncoding:

  Because Exonerate doesn’t return the validated structured data, validating based on these filters will likely require a costly decode/parse step whose results will be immediately thrown away.

• dictionaries

Note:

• by default, ALL strings are considered to be invalid unless they are valid UTF-8 encodings and will be validated. If you require a raw binary, for example if you are ingesting raw data in multipart/form-encoded, use the {"format": "binary"} filter on your string.

Installation

Add the following lines to your mix.exs

  defp deps do
    [
      {:exonerate, "~> 1.1.0", runtime: false},
    ]
  end

Quick Start

defmodule SchemaModule do
  require Exonerate

  Exonerate.function_from_string(:def, :validate_input, """
  {
    "type":"object",
    "properties":{
      "parameter":{"type":"integer"}
    }
  }
  """)
end

iex> SchemaModule.validate_input("some string")
{:error, error_value: "some string", instance_location: "/", absolute_keyword_location: "#/type"}

iex> SchemaModule.validate_input(%{"parameter" => "2"})
{:error, error_value: "2", instance_location: "/parameter", absolute_keyword_location: "#/properties/parameter/type"}

iex> SchemaModule.validate_input(%{"parameter" => 2})
:ok

Licensing notes

This software contains verbatim code from https://github.com/json-schema-org/JSON-Schema-Test-Suite which is copyright Julian Berman, et. al, and released under the MIT license.