Route Corrector Middleware for Express.js

A middleware for Express.js applications that captures potential typos in your route paths and redirects (or suggests) the correct path to the user using the Levenshtein string similarity algorithm.

Usage

Basic Setup

In the following example, the user will be redirected to /about if they visit /abotu or /abuot. It will also respect URL parameters, so /prodcts/1/ifo will redirect to /products/1/info.

import routeCorrector from 'route-corrector';

app.use(routeCorrector());

app.get('/about', (req, res) => res.send('About Page'));
app.get('/products/:productId/info', (req, res) => res.send(`Product ${req.params.productId}`));


app.listen(3000);

With Custom Redirects

If you're aware of commonly mistyped paths or have restructured your application and want to manually specify typo redirects, use custom redirects:

import routeCorrector from 'route-corrector';

app.use(routeCorrector({
    customRedirects: {
        '/me': '/dashboard'
    }
}));

Whitelist & Blacklist

For granular control over which routes should be processed by the middleware, use the whitelist (to exclusively include paths) and blacklist (to exclude paths):

import routeCorrector from 'route-corrector';

app.use(routeCorrector({
    whitelist: ['/about', '/contact'],
    blacklist: ['/admin']
}));

Suggest Mode

In suggest mode, the middleware doesn't redirect. Instead, it sets the suggested route in res.locals.suggestedRoute.

import routeCorrector from 'route-corrector';

app.use(typoRedirectMiddleware({
    suggestOnly: true
}));

app.use((req, res, next) => {
    if (res.locals.suggestedRoute) {
        res.send(`Did you mean ${res.locals.suggestedRoute}?`);
    } else {
        next();
    }
});

API

typoRedirectMiddleware(options?)

Creates and returns the middleware.

options

Type: object

threshold

Type: number

Define the distance threshold below which a typo suggestion/redirect occurs. For Levenshtein, a common value is around 2 or 3, depending on the average length of your routes.

Default:

• Levenshtein: 2

customRedirects

Type: Record<string, string>

A map of mistyped paths to their correct paths.

whitelist

Type: string[]

List of paths that should only be processed by the middleware.

blacklist

Type: string[]

List of paths that should be skipped by the middleware.

suggestOnly

Type: boolean

When set to true, the middleware won't redirect but instead set the suggested path in res.locals.suggestedRoute.