NextJS: How do I get exportPathMap page data? I don't see it in getStaticProps - reactjs

Question

I have set up exportPathMap but I get an empty object when exporting getStaticProps from my component. I don't understand how I'm supposed to access it?
// next.config.js
exportPathMap: async function (
defaultMapPath,
{ dev, dir, outDir, distDir, buildId }
) {
const paths = {}
const response = await fetch(...)
const data = await response.json()
data.forEach((item) => {
paths[`/item/${item.id}`] = {
page: '/itemPage',
query: {
item,
},
}
})
return paths
},
And
// itemPage.js
...
export async function getStaticProps(props) {
console.log('props', props) // returns "props {}""
return {
props: props
}
}
...

Answer 1

It's difficult to find it specifically stated in the documentation right now, but here are your options.
OPTION 1
Use getStaticPaths and getStaticProps like so (from "with-static-export" in the nextJS examples)
// [id].js post file
export async function getStaticPaths() {
const response = await fetch(
'https://jsonplaceholder.typicode.com/posts?_page=1'
)
const postList = await response.json()
return {
paths: postList.map(post => {
return {
params: {
id: `${post.id}`,
},
}
}),
fallback: false,
}
}
export async function getStaticProps({ params }) {
// fetch single post detail
const response = await fetch(
`https://jsonplaceholder.typicode.com/posts/${params.id}`
)
const post = await response.json()
return {
props: post,
}
}
OPTION 2
Use exportPathMap AND getInitialProps
// item.js
...
Page.getInitialProps = function (context) {
return context.query.item
}
// next.config.js
module.exports = {
// ...Same as in your question...
}
Both will allow you to have static optimization. With Option 1, you need not export, next build is sufficient. For Option 2 you will need to run next export
From: https://nextjs.org/docs/advanced-features/static-html-export
If your pages don't have getInitialProps you may not need next export at all; next build is already enough thanks to Automatic Static Optimization.
Another note: You can use both methods inside a single project.