TypeScript JSON Validator
Automatically generate a validator using JSON Schema and AJV for any TypeScript type.
Usage
Define a type in src/Example.ts, e.g.:
export default interface ExampleType {
value: string;
/**
* @TJS-format email
*/
email?: string;
/**
* @default 42
*/
answer: number;
}To generate a validator, run:
npx typescript-json-validator src/Example.ts ExampleType
This will generate src/Example.validator.ts, which you can use:
import { readFileSync } from 'fs';
import validate from './Example.validator.ts';
const value: unknown = JSON.parse(readFileSync(process.argv[2], 'utf8'));
// this will through a clear error if `value` is not of the
// correct type. It will also fill in any default values
const validatedValue = validate(value);
console.log(validatedValue.value);Note that types will be validated automatically, but you can also use annotations to add extra runtime checks, such as e-mail formatting. For annotations see: https://github.com/YousefED/typescript-json-schema#annotations
CLI Docs
Usage: typescript-json-schema <path-to-typescript-file> <type>
Options:
--help Show help [boolean]
--version Show version number [boolean]
--refs Create shared ref definitions.
[boolean] [default: true]
--aliasRefs Create shared ref definitions for the type aliases.
[boolean] [default: false]
--topRef Create a top-level ref definition.
[boolean] [default: false]
--titles Creates titles in the output schema.
[boolean] [default: false]
--defaultProps Create default properties definitions.
[boolean] [default: true]
--noExtraProps Disable additional properties in objects by default.
[boolean] [default: false]
--propOrder Create property order definitions.
[boolean] [default: false]
--typeOfKeyword Use typeOf keyword (https://goo.gl/DC6sni) for
functions. [boolean] [default: false]
--required Create required array for non-optional properties.
[boolean] [default: true]
--strictNullChecks Make values non-nullable by default.
[boolean] [default: true]
--ignoreErrors Generate even if the program has errors.
[boolean] [default: false]
--validationKeywords Provide additional validation keywords to include.
[array] [default: []]
--excludePrivate Exclude private members from the schema.
[boolean] [default: false]
--uniqueNames Use unique names for type symbols.
[boolean] [default: false]
--include Further limit tsconfig to include only matching
files. [array]
--rejectDateType Rejects Date fields in type definitions.
[boolean] [default: false]
--id ID of schema. [string] [default: ""]
--format formats validation mode ('fast' by default). Pass
'full' for more correct and slow validation or false
not to validate formats at all. E.g., 25:00:00 and
2015/14/33 will be invalid time and date in 'full'
mode but it will be valid in 'fast' mode.
[choices: "fast", "full"] [default: "fast"]
--coerceTypes Change data type of data to match type keyword. e.g.
parse numbers in strings [boolean] [default: false]
--strictAll Value for all ajv strict options, unless overriden
by other options (https://bit.ly/3flXX6z)
[choices: "log", true, false] [default: false]
--strict Value for all ajv strict options, unless overriden
by other options (https://bit.ly/3flXX6z)
[choices: "log", true, false]
--strictSchema Prevent unknown keywords, (https://bit.ly/3flXX6z)
[choices: "log", true, false]
--strictNumbers Whether to accept NaN and Infinity as number types
during validation, (https://bit.ly/3flXX6z)
[choices: "log", true, false]
--strictTypes Imposes additional restrictions on how type keyword
is used, (https://bit.ly/3rfsetf)
[choices: "log", true, false]
--strictTuples https://bit.ly/3FruEKe [choices: "log", true, false]
--strictRequired Logs warning or throws exception if the property
used in "required" keyword is not defined in
"properties" keyword in the same or some parent
schema relating to the same object (
(https://bit.ly/3rd5Bpf)
[choices: "log", true, false]
--collection Process the file as a collection of types, instead
of one single type. [boolean] [default: false]
--useNamedExport Type name is a named export, rather than the default
export of the file [boolean] [default: false]
--output overrides filename [string]
--separateSchemaFile save json schema to a separate .json file
[boolean] [default: false]
-* [default: []]
License
MIT