1/*
2 * Copyright 2015-present Facebook, Inc.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#pragma once
18
19#include <folly/ExceptionWrapper.h>
20#include <folly/Range.h>
21#include <folly/dynamic.h>
22
23/**
24 * Validation according to the draft v4 standard: http://json-schema.org/
25 *
26 * If your schema is invalid, then it won't validate anything. For example, if
27 * you set "type": "invalid_type" in your schema, then it won't check for any
28 * type, as if you had left that property out. If you want to make sure your
29 * schema is valid, you can optionally validate it first according to the
30 * metaschema.
31 *
32 * Limitations:
33 * - We don't support fetching schemas via HTTP.
34 * - We don't support remote $refs.
35 * - We don't support $ref via id (only by path).
36 * - We don't support UTF-8 for string lengths, i.e. we will count bytes for
37 * schemas that use minLength/maxLength.
38 */
39
40namespace folly {
41namespace jsonschema {
42
43/**
44 * Interface for a schema validator.
45 */
46struct Validator {
47 virtual ~Validator() = 0;
48
49 /**
50 * Check whether the given value passes the schema. Throws if it fails.
51 */
52 virtual void validate(const dynamic& value) const = 0;
53
54 /**
55 * Check whether the given value passes the schema. Returns an
56 * exception_wrapper indicating success or what the failure was.
57 */
58 virtual exception_wrapper try_validate(const dynamic& value) const
59 noexcept = 0;
60};
61
62/**
63 * Make a validator that can be used to check various json. Thread-safe.
64 */
65std::unique_ptr<Validator> makeValidator(const dynamic& schema);
66
67/**
68 * Makes a validator for schemas. You should probably check your schema with
69 * this before you use makeValidator().
70 */
71std::shared_ptr<Validator> makeSchemaValidator();
72} // namespace jsonschema
73} // namespace folly
74