"divide" Directive for Client-Server Code Separation in Next.js

[yonimor88]

Problem Statement

Currently, Next.js requires strict separation of server and client components using the "use client" directive. This often results in numerous small client components being extracted into separate files, leading to increased project complexity, reduced developer efficiency due to constant file switching and debugging challenges when managing interactions between client and server logic.

For developers working on highly interactive applications, maintaining separate files for minimal client-side interactivity can be frustrating and time-consuming.

Proposal

Introduce a new directive, tentatively named "divide" or a similar name, which allows developers to write both server and client logic within a single file, reducing complexity while maintaining proper code separation during compilation.

How It Works

• The Next.js compiler would parse the "divide" directive to split server and client code during the build process.
• Server-side logic will be processed by Node.js, while client-side logic will be bundled for the browser.
• Import boundaries would be handled to ensure separation without runtime conflicts.

Benefits

• Improved Developer Experience: Reduces the need for multiple files, keeping related logic together.
• Simplified Codebase: Makes it easier to understand and maintain complex applications.
• Reduced Debugging Time: Easier to track logic flow without jumping between files

Example Usage:

"use server"
// Server-side logic
import { getUserData } from "@/lib/db";

export async function fetchUser(id) {
  return await getUserData(id);
}

"divide"

"use client"
// Client-side logic
import { useState } from "react";
import { fetchUser } from "./thisFile";

export default function UserComponent({ id }) {
  const [user, setUser] = useState(null);

  async function loadUser() {
    const data = await fetchUser(id);
    setUser(data);
  }

  return <button onClick={loadUser}>Load User</button>;
}

Considerations

• Additional compilation time due to code parsing and separation.
• Proper enforcement of client-server boundaries to prevent unintended imports.

Conclusion

The "divide" directive could significantly enhance developer productivity by offering a more intuitive way to structure Next.js applications, while maintaining the existing benefits of the client-server model.