matchedData()

matchedData()

import { matchedData } from 'express-validator';
matchedData(req, options?: {
  includeOptionals?: boolean,
  onlyValidData?: boolean,
  locations?: Location[],
})

Extracts data validated and/or sanitized by express-validator from the request, and returns an object with them.

app.post(
  '/contact-us',
  [body('email').isEmail(), body('message').notEmpty(), body('phone').optional().isMobilePhone()],
  (req, res) => {
    const result = validationResult(req);
    if (!result.isEmpty()) {
      // handle validation errors
      return res.send('Please fix the request');
    }

    const data = matchedData(req);
    // If phone isn't set:
    // => { email: 'foo@bar.com', message: 'Hi hello' }
    // If phone is set:
    // => { email: 'foo@bar.com', message: 'Hi hello', phone: '+1223334444' }
  },
);

With optional data

By default, matchedData doesn't return data that is optional and wasn't present in the request.
You can set options.includeOptionals to true to change this behavior.

app.post(
  '/contact-us',
  [body('email').isEmail(), body('message').notEmpty(), body('phone').optional().isMobilePhone()],
  (req, res) => {
    const data = matchedData(req, { includeOptionals: true });
    // If phone isn't set:
    // => { email: 'foo@bar.com', message: 'Hi hello', phone: undefined }
  },
);

tip

See the documentation on .optional() to learn more.

With invalid data

By default, matchedData return only data that is valid; that is, if the request contains invalid data, it's omitted from the result.
You can set options.onlyValidData to false to change this behavior.

app.post('/signup', body('email').isEmail(), body('password').notEmpty(), (req, res) => {
  const data = matchedData(req, { onlyValidData: false });
  // => { email: 'not_actually_an_email', password: '' }
});

Selecting data from specific locations

By default, matchedData selects data validated on all of request's locations. You can change this behavior by setting options.locations to a list of the locations which you wish to select data from:

app.post(
  '/signup',
  [body('email').isEmail(), body('password').notEmpty(), query('subscribe_newsletter').isBoolean()],
  (req, res) => {
    const data = matchedData(req);
    // => { email: 'foo@bar.com', password: '12345', subscribe_newsletter: true }

    const data2 = matchedData(req, { locations: ['query'] });
    // => { subscribe_newsletter: true }
  },
);

Typescript usage

The matchedData function signature accepts passing a Generic Type as the return type.

The default type is Record<string, any>.

import { matchedData } from 'express-validator';

app.post(
  '/contact-us',
  [body('email').isEmail(), body('message').notEmpty(), body('phone').optional().isMobilePhone()],
  (req, res) => {
    const result = validationResult(req);
    if (!result.isEmpty()) {
      // handle validation errors
      return res.send('Please fix the request');
    }

    const result = matchedData<{
      email: string;
      message: string;
      phone?: string;
    }>(req);
  },
);