v7.0.0
Please note: this document covers the changes from v6.12.6.
The main changes
- support of JSON Schema draft-2019-09 features:
unevaluatedProperties
andunevaluatedItems
, dynamic recursive references and other additional keywords. - comprehensive support for standalone validation code - compiling one or multiple schemas to standalone modules with one or multiple exports.
- to reduce the mistakes in JSON schemas and unexpected validation results, strict mode is added - it prohibits ignored or ambiguous JSON Schema elements. See Strict mode and Options for more details
- to make code injection from untrusted schemas impossible, code generation is fully re-written to be type-level safe against code injection.
- to simplify Ajv extensions, the new keyword API that is used by pre-defined keywords is available to user-defined keywords - it is much easier to define any keywords now, especially with subschemas.
- schemas are compiled to ES6 code (ES5 code generation is supported with an option).
- to improve reliability and maintainability the code is migrated to TypeScript.
- separate Ajv classes from draft-07 and draft-2019-09 support with different default imports (see Getting started or v7.0.0-beta.5 for the details).
Please note:
- the support for JSON-Schema draft-04 is removed - if you have schemas using "id" attributes you have to replace them with "$id" (or continue using version 6 that will be supported until 02/28/2021).
- all formats are separated to ajv-formats package - they have to be explicitly added if you use them.
- Ajv instance can only be created with
new
keyword, as Ajv is now ES6 class. - browser bundles are automatically published to ajv-dist package (but still available on cdnjs.com).
- order of schema keyword validation changed - keywords that apply to all types (allOf etc.) are now validated first, before the keywords that apply to specific data types. You can still define custom keywords that apply to all types AND are validated after type-specific keywords using option
post: true
in keyword definition. - regular expressions in keywords "pattern" and "patternProperties" are now used as if they had unicode "u" flag, as required by JSON Schema specification - it means that some regular expressions that were valid with Ajv v6 are now invalid (and vice versa).
Better TypeScript support:
- Methods
compile
andcompileAsync
now return type-guards - see Getting started. - Method
validate
is a type-guard. - Better separation of asynchronous schemas on type level.
- Type utility JSONSchemaType that generates the type for JSON Schema for type interface in the type parameter - it simplifies writing schemas (no unions support at the moment).
API changes:
- addVocabulary - NEW method that allows to add an array of keyword definitions.
- addKeyword - keyword name should be passed as property in definition object, not as the first parameter (old API works with "deprecated" warning). Also "inline" keywords support is removed, code generation keywords can now be defined with "code" keyword - the same definition format that is used by all pre-defined keywords
- Ajv no longer allows to create the instance without
new
keyword (it is ES6 class).
Added options (and defaults):
- strict: true - strict mode
- strictTypes: "log" - prevent mistakes related to type keywords and keyword applicability (see Strict Types)
- strictTuples: "log" - prevent incomplete tuple schemas (see Prohibit unconstrained tuples)
- allowUnionTypes: false - allow multiple non-null types in "type" keyword
- allowMatchingProperties: false - allow overlap between "properties" and "patternProperties" keywords
- loopEnum: Infinity - optimise validation of enums, similar to
loopRequired
- validateFormats: true - enable format validation
- code: {optimize: number|boolean} - control code optimisation
- code: {es5: true} - generate ES5 code, the default is to generate ES6 code.
- code: {lines: true} - add line breaks to generated code - simplifies debugging of compiled schemas when you need it
Changed options:
keywords
- now expects the array of keyword definitions (old API works with "deprecated" warning)
Removed options:
- errorDataPath - was deprecated, now removed.
- format -
validateFormats: false
can be used instead, old format mode can be chosen via ajv-formats package. - nullable:
nullable
keyword is supported by default. - jsonPointers: JSONPointers are used to report errors by default,
jsPropertySyntax: true
(deprecated) can be used if old format is needed. - extendRefs: $ref siblings are validated by default (consistent with draft 2019-09),
ignoreKeywordsWithRef
(deprecated) can be used instead to ignore $ref siblings. - missingRefs: now exception is always thrown. Pass empty schema with $id that should be ignored to ajv.addSchema.
- processCode: replaced with
code: {process: (code, schemaEnv: object) => string}
. - sourceCode: replaced with
code: {source: true}
. - schemaId: removed, as JSON Schema draft-04 is no longer supported.
- strictDefaults, strictKeywords, strictNumbers: it is default now, controlled with
strict
. - uniqueItems: '"uniqueItems" keyword is always validated.
- unknownFormats: the same can be achieved by passing true for formats that need to be ignored via
ajv.addFormat
orformats
option. - cache and serialize: Map is used as cache, schema object as key.