We've been exploring the best practices for managing metadata in MDX files within a Next.js environment. Recently, we built an example app using Next.js and @next/mdx, which you can learn about in detail in our article here.

In this post, we want to share why we chose to use Metadata Objects over frontmatter for handling metadata in our MDX files.

Why Metadata Objects?

1. Dynamic Data Handling

One of the primary reasons we opted for Metadata Objects is the flexibility they offer in handling dynamic data. Unlike static frontmatter, metadata objects can include dynamic expressions and functions, making them ideal for scenarios where metadata values need to be computed at runtime.

For example, setting a dynamic title based on the current year:

mdxCopy
export const metadata = {
  title: `Post Title - ${new Date().getFullYear()}`,
  date: new Date().toISOString(),
};

## {metadata.title}

Published on: {metadata.date}

2. Integration with TypeScript

With Metadata Objects, we can leverage TypeScript to enforce type safety, reducing the risk of runtime errors. This aligns well with the TypeScript-first approach that many modern Next.js projects are adopting.

mdxCopy
import { Metadata } from "some-type-definitions";

export const metadata: Metadata = {
  title: "My Post",
  date: "2024-03-01",
};

## {metadata.title}

Published on: {metadata.date}

3. Component-Based Architecture

Next.js thrives on its component-based architecture. Using metadata as components or objects keeps everything within the same paradigm, making the codebase more cohesive and easier to manage.

mdxCopy
export const metadata = {
  title: "My Post",
  description: "This is a post about Next.js",
};

## {metadata.title}

{metadata.description}

4. Enhanced Flexibility

Metadata objects can include complex data structures and functions, providing a level of flexibility that static frontmatter cannot match.

mdxCopy
export const metadata = {
  title: "Dynamic Title",
  generateDescription: () => `Generated at ${new Date().toLocaleString()}`,
};

## {metadata.title}

{metadata.generateDescription()}

Considerations

Consistency

While using metadata objects is flexible, it can lead to inconsistent structures if not properly standardized. At MDXBlog, we've established guidelines to ensure our metadata structures are consistent across all MDX files.

Learning Curve

For developers new to Next.js or React, integrating metadata directly within components might have a steeper learning curve compared to the simpler YAML frontmatter. However, the long-term benefits of flexibility and type safety outweigh the initial learning challenges.

Tooling and Ecosystem

While the Next.js ecosystem is well-suited to handle metadata objects, some third-party tools might still expect traditional frontmatter. We ensure our tools support or can be adapted to our metadata structure.

Conclusion

We believe that using Metadata Objects is a modern, flexible approach that aligns perfectly with the dynamic nature of Next.js applications. This method offers enhanced flexibility, better integration with TypeScript, and maintains a consistent component-based architecture.

For more details on how we built our example app using Next.js and @next/mdx, check out our detailed article here.