json-schema-codec-generator
v1.0.1
Published
Generate typed codec validator code from collections of json-schema
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JSON-Schema Codec Generator
Generate typed codec validator code from collections of inter-related json-schema
Generate typed codecs from collections of json-schema using the included library or the bundled CLI.
- Supports collections of schemas having
$reference
s between one-another. - Produces type-safe validator functions via ajv.
- Designed for code-generation to maximize runtime performance.
Installation
To install the CLI, the recommended approach is to install it globally.
npm install -g json-schema-codec-generator
Alternatively, you can use npx
to install and run it on-demand.
npx json-schema-codec-generator --help
CLI Usage
Given a folder full of .json
files containing JSON-Schema definitions in ./path/to/my/schema/dir
, the following will produce:
./codecs/index.js
-- JavaScript code that exports aValidatorFunction<T>
function for each discovered schema. These functions have no runtime dependencies and thus can be used in any JavaScript runtime.Each Schema passed in will have a corresponding ValidatorFunction generated.
./codecs/index.d.ts
-- TypeScript definition files for the generated codecs. These type definitions ensure that code consuming the codecs will benefit from compile-time and edit-time type hinting.
json-schema-codec-generator --input ./path/to/my/schema/dir --output ./codecs/
ValidatorFunction
export interface ErrorObject {
instancePath: string;
message?: string;
data?: unknown;
}
export interface ValidatorFunction<T> {
(obj: unknown): obj is T;
errors?: ErrorObject[];
}
For a given schema named Bookmark
, a validator function named validateBookmark
of type ValidatorFunction<Bookmark>
will be exported as well as a Bookmark
type. These functions can be used as type assertions. Immediately after calling a validator function and seeing a validation failure, the validation errors can be recovered from validateBookmark.errors
.