Vercel Edge Middleware for redirection.io

This package allows to use redirection.io within a Vercel Edge Middleware.

Look at our documentation about our Vercel Edge Middleware integration here: https://redirection.io/documentation/developer-documentation/vercel-middleware-integration

Installation

npm install @redirection.io/vercel-middleware

// or with yarn
yarn add @redirection.io/vercel-middleware

Usage

Create a middleware.ts file in the root of your Vercel application (at the same level as the app or pages folders, possibly in a src folder if your project uses one) with the following content:

import redirectionioMiddleware from "@redirection.io/vercel-middleware";

export default redirectionioMiddleware;

export const config = {
    unstable_allowDynamic: ["/node_modules/@redirection.io/**"],
};

Set the REDIRECTIONIO_TOKEN environment variable in your vercel project settings.

Then, deploy your project to Vercel.

vercel deploy

Usage with an existing middleware

You may have an existing middleware in your Vercel project. In this case, you can use the createRedirectionIoMiddleware function which allows to chain existing middleware with redirection.io middleware.

import { createRedirectionIoMiddleware } from "@redirection.io/vercel-middleware";

const myExistingMiddleware = (request: Request) => {
    // Your existing middleware logic

    return next();
};

const middleware = createRedirectionIoMiddleware({
    previousMiddleware: myExistingMiddleware, // In this case your middleware is executed before redirection.io middleware
    nextMiddleware: myExistingMiddleware, // In this case your middleware is executed after redirection.io middleware
    // Optional: matcher to specify which routes should be ignored by redirection.io middleware
    // Default: "^/((?!api/|_next/|_static/|_vercel|[\\w-]+\\.\\w+).*)$"
    matcherRegex: "^/((?!api/|_next/|_static/|_vercel|[\\w-]+\\.\\w+).*)$",
    // Optional: If light, redirection.io middleware will only redirect and not override the response
    // Default: "full"
    mode: "light",
    // Optional: If true, redirection.io middleware will log information in Redirection.io
    // Default: true
    logged: true,
});

export default middleware;

By default, our middleware ignores certain routes even if there's an exported configuration. The ignored routes are:

• /api/* routes
• /next/* (Next.js internals)
• /static/* (inside /public)
• all root files inside /public (e.g. /favicon.ico)

If you want the middleware to handle all routes without any exclusions, you can set the matcherRegex option to null:

createRedirectionIoMiddleware({ matcherRegex: null });

Here's a summary of the middleware options:

Option	Type	Description
previousMiddleware	Function	Middleware to be executed before redirection.io middleware
nextMiddleware	Function	Middleware to be executed after redirection.io middleware
matcherRegex	String or null	Regex to specify which routes should be handled by redirection.io middleware
mode	full or light	If light, redirection.io middleware will only redirect and not override the response (default: full)
logged	Boolean	If true, redirection.io middleware will log information in Redirection.io (default: true)

Light mode

The response rewriting features (e.g., SEO overrides, custom body, etc.) of redirection.io are currently not compatible with React Server Components (RSC). This is due to the fact that Vercel’s middleware implementation does not follow standard middleware protocols, requiring us to fetch requests, which is incompatible with both RSC and Vercel’s implementation.

However, we provide a light mode that supports RSC by offering only the redirection functionality. To enable this mode, simply set the mode option to light.

This allows you to implement redirection behavior without modifying response content, ensuring smooth operation with RSC.

const middleware = createRedirectionIoMiddleware({
    // …
    mode: "light",
});

Next.js

If you are using next.js middlewares, you can use the createRedirectionIoMiddleware method from @redirection.io/vercel-middleware/next which is compatible with NextRequest type.

- import { createRedirectionIoMiddleware } from "@redirection.io/vercel-middleware";
+ import { createRedirectionIoMiddleware } from "@redirection.io/vercel-middleware/next";
+ import { NextRequest } from "next/server";

- const myExistingMiddleware = (request: Request) => {
+ const myExistingMiddleware = (request: NextRequest) => {
    return next();
};

Development

Build

yarn run tsc