This module provides a middleware for Oak to validate request using JSON Schema.

Compatibility: Oak v14.0.0+

• Validate request query, body, header parameters
• Sanitize request query and body parameters
• Define custom error handler
• Create custom validators and sanitizers
• Stack up multiple validators and sanitizers

Import module with:

import * as mod from "@trackerforce/validator4oak@[VERSION]";
import * as mod from "https://deno.land/x/validator4oak@v[VERSION]/mod.ts";

Usage

Validate query parameters

const router = new Router();
const { query } = ValidatorMiddleware.createMiddleware<Context, Next>();
const { isUrl } = ValidatorFn.createValidator();

router.get('/api/v1/shorten',
  query([
    { key: 'url', validators: [isUrl()] },
  ]), (ctx: Context) => {
    // ...
  },
);

Optional query parameters:

router.get('/api/v1/shorten',
  query([
    { key: 'url', optional: true },
  ]), (ctx: Context) => {
    // ...
  },
);

Validate body parameters

Key body parameters can be accessed using complex keys, e.g. order.number.
Since Oak v14, body request can only be consumed once, so you'll need to use state.request_body to access it within the route.

router.post('/checkout/v1/confirm',
  body([
    { key: 'order.number', validators: [isNumeric()] },
  ]), (ctx: Context) => {
    // ...
  },
);

It's also possible to validate array of complex objects using isArray() and * wildcard to access array elements.

router.post('/checkout/v1/confirm',
  body([
    { key: 'order.items', validators: [isArray()] },
    { key: 'order.items.*.sku', validators: [isString()] },
    { key: 'order.items.*.quantity', validators: [isNumeric()] },
  ]), (ctx: Context) => {
    // ...
  },
);

Validate header parameters

const { header } = ValidatorMiddleware.createMiddleware<Context, Next>();
const { isNumber } = ValidatorFn.createValidator();

router.post('/example/v1/shorten',
  header([
    { key: 'x-api-key', validators: [isNumber()] },
  ]), (ctx: Context) => {
    // ...
  },
);

Sanitize parameters

const { escape } = ValidatorSn.createSanitizer();

router.post('/message/v1/send',
  body([
    { key: 'message', validators: [hasLenght({ max: 500 })], sanitizers: [escape()] },
  ]), (ctx: Context) => {
    // ...
  },
);

Testing

Use deno task test to run tests.

Check Oak compatibility

Replace the Oak version in the test/deps.ts file to verify if middleware is compatible.

export { Router, Context, Application } from "jsr:@oak/oak@[OAK_VERSION]";

Contributing

Please do open an issue if you have some cool ideas to contribute.