Validator4Oak
Validator & Sanitizer middleware for Oak.

This module provides a middleware for Oak to validate and sanitize requests.

Compatibility: Oak v14.0.0+

Validate request query, body, form and header parameters
Sanitize request parameters
Define custom error handlers
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, check } = ValidatorMiddleware.createMiddleware<Context, Next>();
const { isUrl } = ValidatorFn.createValidator();

router.get('/api/v1/shorten',
  query(check('name').ifValue(isUrl())), 
  (ctx: Context) => {
    // ...
  },
);

Optional query parameters:

router.get('/api/v1/shorten',
  query(check('url').isOptional()), 
  (ctx: Context) => {
    // ...
  },
);

Validate body and form 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.

Using body:

router.post('/checkout/v1/confirm',
  body(check('order.number').ifValue(isNumeric())),
  (ctx: Context) => {
    // ...
    const body = ctx.state.request_body; // Access the body request
    // ...
  },
);

Using form:

router.post('/checkout/v1/confirm',
  form(check('order.number').ifValue(isNumeric())), 
  (ctx: Context) => {
    // ...
    const body = ctx.state.request_body; // Access the form request
    // ...
  },
);

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

router.post('/checkout/v1/confirm',
  body(
    check('order.items').ifValue(isArray()),
    check('order.items.*.sku').ifValue(isString(), hasLenght({ min: 6 })),
    check('order.items.*.quantity').ifValue(isNumeric())
  ), (ctx: Context) => {
    // ...
  },
);

Validate header parameters

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

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

Sanitize parameters

const { escape, trim } = ValidatorSn.createSanitizer();
const { hasLenght } = ValidatorFn.createValidator();

router.post('/message/v1/send',
  body(
    check('message')
      .sanitizeWith(escape(), trim())
      .ifValue(hasLenght({ max: 500 }))
  ), (ctx: Context) => {
    // ...
  },
);

Testing

Use deno task test to run tests.

Check Oak compatibility

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

export * from "jsr:@oak/oak@[OAK_VERSION]";

Contributing

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