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Use getStaticProps and getServerSideProps as react hooks

next-data-hooks is a small and simple lib that lets you write React hooks for data queries in Next.js by lifting static props into React Context.

import { createDataHook } from 'next-data-hooks';

const useBlogPost = createDataHook('BlogPost', async (context) => {
  const { slug } = context.params;

  return; // ... get the blog post
});

function BlogPost() {
  const { title, content } = useBlogPost();

  return (
    <>
      <h1>{title}</h1>
      <p>{content}</p>
    </>
  );
}

BlogPost.dataHooks = [useBlogPost];

export default BlogPost;

Why?

  1. Writing one large query per page doesn't organize well. Asynchronous data fetching frameworks like apollo, relay, and react-query already allow you to write the queries closer to the component. Why can't static data queries be written closer to the component too?
  2. Works better with TypeScript β€” when you import a data hook, you're also importing its return type. When you call the hook inside your component, the types are already there.

Why not?

The primary thing this library offers is a pattern organizing getStaticProps/getServerSideProps.

⚠️ Note: It does not offer any more capabilities than vanilla Next.js.

See this question: Why aren't the data hooks parameterized?

Example

See the example in this repo for some ideas on how to organize your static data calls using this hook.

Installation

  1. Install
npm i next-data-hooks

or

yarn add next-data-hooks
  1. Add the babel plugin

At the root, add a .babelrc file that contains the following:

{
  "presets": ["next/babel"],
  "plugins": ["next-data-hooks/babel"]
}

⚠️ Don't forget this step. This enables code elimination to eliminate server-side code in client code.

  1. Add the provider to _app.tsx or _app.js
import { AppProps } from 'next/app';
import { NextDataHooksProvider } from 'next-data-hooks';

function App({ Component, pageProps }: AppProps) {
  const { children, ...rest } = pageProps;

  return (
    <NextDataHooksProvider {...rest}>
      <Component {...rest}>{children}</Component>
    </NextDataHooksProvider>
  );
}

Usage

  1. Create a data hook. This can be in the same file as the component you're using it in or anywhere else.
import { createDataHook } from 'next-data-hooks';

// this context is the GetStaticPropsContext from 'next'
//                                                      πŸ‘‡
const useBlogPost = createDataHook('BlogPost', async (context) => {
  const slug = context.params?.slug as string;

  // do something async to grab the data your component needs
  const blogPost = /* ... */;

  return blogPost;
});

export default useBlogPost;
TypeScript User?

Note: For TypeScript users, if you're planning on only using the data hook in the context of getServerSideProps, you can import the provided type guard, isServerSidePropsContext, to narrow the type of the incoming context.

import { createDataHook, isServerSidePropsContext } from 'next-data-hooks';

const useServerSideData = createDataHook('Data', async (context) => {
  if (!isServerSidePropsContext(context)) {
    throw new Error('This data hook only works in getServerSideProps.');
  }

  // here, the type of `context` has been narrowed to the server side conext
  const query = context.req.query;
});

export default useServerSideData;
  1. Use the data hook in a component. Add it to a static prop in an array with other data hooks to compose them downward.
import ComponentThatUsesDataHooks from '..';
import useBlogPost from '..';
import useOtherDataHook from '..';

function BlogPostComponent() {
  const { title, content } = useBlogPost();
  const { other, data } = useOtherDataHook();

  return (
    <article>
      <h1>{title}</h1>
      <p>{content}</p>
      <p>
        {other} {data}
      </p>
    </article>
  );
}

// compose together other data hooks
BlogPostComponent.dataHooks = [
  ...ComponentThatUsesDataHooks.dataHooks,
  useOtherDataHooks,
  useBlogPost,
];

export default BlogPostComponent;
  1. Pass the data hooks down in getStaticProps or getServerSideProps.
import { getDataHooksProps } from 'next-data-hooks';
import { GetStaticPaths, GetStaticProps } from 'next';
import BlogPostComponent from '..';

export const getStaticPaths: GetStaticPaths = async (context) => {
  // return static paths...
};

// NOTE: this will also work with `getServerSideProps`
export const getStaticProps: GetStaticProps = async (context) => {
  const dataHooksProps = await getDataHooksProps({
    context,
    // this is an array of all data hooks from the `dataHooks` static prop.
    //                             πŸ‘‡πŸ‘‡πŸ‘‡
    dataHooks: BlogPostComponent.dataHooks,
  });

  return {
    props: {
      // spread the props required by next-data-hooks
      ...dataHooksProps,

      // add additional props to Next.js here
    },
  };
};

export default BlogPostComponent;

Useful Patterns

A separate routes directory

Next.js has a very opinionated file-based routing mechanism that doesn't allow you to put a file in the /pages folder without it being considered a page.

Simply put, this doesn't allow for much organization.

With next-data-hooks, you can treat the /pages folder as a folder of entry points and organize files elsewhere.

my-project
# think of the pages folder as entry points to your routes
β”œβ”€β”€ pages
β”‚   β”œβ”€β”€ blog
β”‚   β”‚   β”œβ”€β”€ [slug].ts
β”‚   β”‚   └── index.ts
β”‚   └── shop
β”‚       β”œβ”€β”€ category
β”‚       β”‚   └── [slug].ts
β”‚       β”œβ”€β”€ index.ts
β”‚       └── product
β”‚           └── [slug].ts
|
# think of each route folder as its own app with it's own components and helpers
└── routes
    β”œβ”€β”€ blog
    β”‚   β”œβ”€β”€ components
    β”‚   β”‚   β”œβ”€β”€ blog-index.tsx
    β”‚   β”‚   β”œβ”€β”€ blog-post-card.tsx
    β”‚   β”‚   └── blog-post.tsx
    β”‚   └── helpers
    β”‚       └── example-blog-helper.ts
    └── shop
        β”œβ”€β”€ components
        β”‚   β”œβ”€β”€ category.tsx
        β”‚   β”œβ”€β”€ product-description.tsx
        β”‚   └── product.tsx
        └── helpers
            └── example-shop-helper.ts

/routes/blog/components/blog-post.tsx

import { createDataHook } from 'next-data-hooks';

// write your data hook in a co-located place
const useBlogPostData = createDataHook('BlogPost', async (context) => {
  const blogPostData = // get blog post data…
  return blogPostData;
});

function BlogPost() {
  // use it in the component
  const { title, content } = useBlogPostData();

  return (
    <article>
      <h1>{title}</h1>
      <p>{content}</p>
    </article>
  );
}

BlogPost.dataHooks = [useBlogPostData];

export default BlogPost;

/pages/blog/[slug].ts

import { GetStaticProps, GetStaticPaths } from 'next';
import { getDataHooksProps } from 'next-data-hooks';
import BlogPost from 'routes/blog/components/blog-post';

export const getStaticPaths: GetStaticPaths = {}; /* ... */

export const getStaticProps: GetStaticProps = async (context) => {
  const dataHooksProps = getDataHooksProps({
    context,
    dataHooks: BlogPost.dataHooks,
  });
  return { props: dataHooksProps };
};

// re-export your component. this file is just an entry point
export default BlogPost;

πŸ‘‹ Note: the above is just an example of how you can use next-data-hooks to organize your project. The main takeaway is that you can re-export page components to change the structure and next-data-hooks works well with this pattern.

Composing data hooks

Each data hook exposes a getData method which is simply the function you pass into createDataHook.

This can be used within other data hooks to pull the same data:

import { createDataHook } from 'next-data-hooks';

const useHook = createDataHook('DataHook', async (context) => {
  return; // ...
});

export default useHook;
import useHook from './';

const useOtherHook = createDataHook('Other', async (context) => {
  const data = await useHook.getData(context);

  // use data to do something…
});

πŸ‘‹ Note: Be aware that this method re-runs the function.

Code elimination

For smaller bundles, Next.js eliminates code that is only intended to run inside getStaticProps.

next-data-hooks does the same by a babel plugin that prefixes your data hook definition with typeof window !== 'undefined' ? <stub> : <real data hook>.

This works because Next.js pre-evaluates the expression typeof window to 'object' in browsers. This will make the above ternary always evaluate to the <stub> in the browser. Terser then shakes away the <real data hook> expression eliminating it from the browser bundle.

If you saw the error Create data hook was run in the browser. then something may have went wrong with the code elimination. Please open an issue.

πŸ‘‹ Note. There may be differences in Next.js's default code elimination and next-data-hooks code elimination. Double check your bundle.