ajv-cli

Command line interface for ajv, one of the fastest json schema validators. Supports JSON, JSON5, and YAML.

Contents

• Installation
• JSON schema version
• Commands
  • Help
  • Validate data
  • Compile schemas
  • Migrate schemas
  • Test validation result
• Ajv options
• Version History, License

Installation

npm install -g ajv-cli

JSON schema language and version

Parameter

--spec

• --spec=draft7

  (default) - support JSON Schema draft-07 (uses

  import Ajv from "ajv"

  )

• --spec=draft2019

  - support JSON Schema draft-2019-09 (uses

  import Ajv from "ajv/dist/2019"

  )

• --spec=draft2020

  - support JSON Schema draft-2020-12 (uses

  import Ajv from "ajv/dist/2020"

  )

• --spec=jtd

  - support JSON Type Definition (uses

  import Ajv from "ajv/dist/jtd"

  )

Commands

Help command

ajv help
ajv help validate
ajv help compile
ajv help migrate
ajv help test

Validate data

This command validates data files against JSON-schema

ajv validate -s test/schema.json -d test/valid_data.json
ajv -s test/schema.json -d test/valid_data.json

You can omit

validate

.json

Parameters

-s

- file name of JSON-schema

Only one schema can be passed in this parameter

-d

- JSON data

Multiple data files can be passed, as in

-r

ajv -s test/schema.json -d "test/valid*.json"

If some file is invalid exit code will be 1.

-r

- referenced schemas

The schema in

-s

$ref

Multiple schemas can be passed both by using this parameter multiple times and with glob patterns. Glob pattern should be quoted and extensions cannot be omitted.

-m

- meta-schemas

Schemas can use any of these schemas as a meta-schema (that is the schema used in

$schema

Multiple meta-schemas can be passed, as in

-r

-c

- custom keywords/formats definitions

You can pass module(s) that define custom keywords/formats. The modules should export a function that accepts Ajv instance as a parameter. The file name should start with ".", it will be resolved relative to the current folder. The package name can also be passed - it will be used in require as is. These modules can be written in TypeScript if you have

ts-node

For example, you can use

-c ajv-keywords

-c ajv-keywords/keywords/typeof

Options

• --errors=

  : error reporting format. Possible values:

  • js

    (default): JavaScript object

  • json

    : JSON with indentation and line-breaks

  • line

    : JSON without indentation/line-breaks (for easy parsing)

  • text

    : human readable error messages with data paths

• --changes=

  : detect changes in data after validation.
  Data can be modified with Ajv options

  --remove-additional

  ,

  --use-defaults

  and

  --coerce-types

  ).
  The changes are reported in JSON-patch format (RFC6902).
  Possible values are

  js

  (default),

  json

  and

  line

  (see

  --errors

  option).

Compile schemas

This command validates and compiles schema without validating any data.

It can be used to check that the schema is valid and to create a standalone module exporting validation function(s).

ajv compile -s schema

compile to module file
ajv compile -s schema -o validate.js
compile to stdout, to allow code formatting (js-beautify has to be installed separately)
ajv compile -s schema -o | js-beautify > validate.js

Parameters

-s

- file name(s) of JSON-schema(s)

Multiple schemas can be passed both by using this parameter multiple times and with glob patterns.

ajv compile -s "test/schema*.json"

-o

- output file for compiled validation function module

If multiple schemas are compiled with this option the module will have multiple exports named as schema $id's or as file names, otherwise the module will export validation function as default export.

ajv compile -s "schema.json" -o "validate_schema.js"

-o

This command also supports parameters

-r

-m

-c

Migrate schemas

This command validates and migrates schema from JSON Schema draft-04 to draft-07, draft-2019-09 or draft-2020-12 using json-schema-migrate package.

The version of JSON Schema is determined by

--spec

"draft7"

"draft2019"

"draft2020"

ajv migrate -s schema

compile to specific file name
ajv migrate -s schema -o migrated_schema.json

Parameters

-s

- file name(s) of JSON-schema(s)

Multiple schemas can be passed both by using this parameter multiple times and with glob patterns.

ajv migrate -s "test/schema*.json"

If parameter

-o

.bak

If migration doesn't change anything in the schema file no changes in files are made.

-o

- output file for migrated schema

Only a single schema can be migrated with this option.

ajv compile -s "schema.json" -o migrated_schema.json

Options

• --indent=

  : indentation in migrated schema JSON file, 4 by default

• --validate-schema=false

  : skip schema validation

Test validation result

This command asserts that the result of the validation is as expected.

ajv test -s test/schema.json -d test/valid_data.json --valid
ajv test -s test/schema.json -d test/invalid_data.json --invalid

If the option

--valid

--invalid

test

This command supports the same options and parameters as validate with the exception of

--changes

Ajv options

You can pass the following Ajv options:

| Option | Description | | ------ | ----------- | | Strict mode | |

--strict=

true

false

log

--strict-schema=

log

false

--strict-tuples=

true

false

--strict-types=

true

false

--strict-required=

true

log

--allow-matching-properties

properties

patternProperties

--allow-union-types

--validate-formats=false

--data

--all-errors

--verbose

--comment

$comment

--inline-refs=

--remove-additional

--use-defaults

--coerce-types

--multiple-of-precision

--messages=false

--loop-required=

required

--loop-enum=

enum

--own-properties

--code-es5

--code-lines

--code-optimize=

false

--code-formats=

Options can be passed using either dash-case or camelCase.

See Ajv Options for more information.

Version History

See https://github.com/ajv-validator/ajv-cli/releases

Licence

MIT