Access Metadata values in server component

Answered

Brown bear posted this in #help-forum

Brown bearOP

2024-11-05T17:50:37.931Z

I have a page with a dynamic route segment /thing/[some]/page.tsx

I want to use a modified version of the dynamic route segment as part of the title, but I also need to use that same modified segment as input to another component.

I do not want to duplicate or re-execute the logic to modify the segment. It should be done once and only once. I do not care about caching or any other alternitives. I just want to know if it is possible to get the metadata from the generateMetadata function, and use it in the component.

export async function generateMetadata({ params }): Promise<Metadata & {modSlug: string}> {
  const { slug } = await params;
  const modSlug = `${slug}-modified`
  return {
    title: `my-site | ${modSlug}`,
    modSlug
  }
}

export default async function Page({ params }) {
  const metadata = ???
  return (
    <SomeOtherComponent modSlug={metadata.modSlug} />
  )
}

Answered by Brown bear

On one hand you are right. calling generateMetadata() will return extra "metadata" attributes that I may not need in my component, but unless generateMetadata is a much more expensive operation than I think it is the bulk of the processing is in my implementation to modify the slug. With the current limitation (cannot just use metedata in a component) I have to execute the logic to modify the slug 2x whether I call generateMetadata() or extract that to a separate function.

function modifySlug({ slug }: { slug: string }) {
  // Assume this is much more complicated than shown
  return `${slug}-modified`
}

export async function generateMetadata({ params }): Promise<Metadata & {modSlug: string}> {
  const { slug } = await params;
  const modSlug = modifySlug({ slug });
  return {
    title: `my-site | ${modSlug}`,
    modSlug
  }
}

export default async function Page({ params }) {
  const { slug } = await params;
  const modSlug = modifySlug({ slug })
  return (
    <SomeOtherComponent modSlug={modSlug} />
  )
}

View full answer

17 Replies

James4u

2024-11-05T18:31:54.679Z

@Brown bear I don't think you have a way to directly access to the meta data
but as long as you are generating meta data inside generateMetadata() function, just abstract the logic into a util function

and then call it again in your page to get the same metadata object if you need it

Brown bearOP

2024-11-05T18:33:54.746Z

I figured as much, but I was hoping I was missing something like a useMetadata hook (wouldnt be a hook since it is a server component but you get the idea).

currently I just call the generateMetadata function in my component, but it feels so needlessly redundant. 😩

export default async function Page({ params }) {
  const metadata = await generateMetadata({ params });
  return (
    <SomeOtherComponent modSlug={metadata.modSlug} />
  )
}

James4u

2024-11-05T18:37:50.231Z

well, what I meant is to create a util function that modifies your slug (in your case)

function modifySlug(slug) {
return `${slug}-modified`;
}

and then use it inside your generateMetadata() and in your page as well

~~It should be more efficient, I can't be sure 100%, but I don't feel calling generateMetadata() in your page is correct~~

~~it won't be throwing any error but just my feeling~~

hmm let me think again, well I think it's fine

Brown bearOP

2024-11-05T20:22:11.456Z

function modifySlug({ slug }: { slug: string }) {
  // Assume this is much more complicated than shown
  return `${slug}-modified`
}

export async function generateMetadata({ params }): Promise<Metadata & {modSlug: string}> {
  const { slug } = await params;
  const modSlug = modifySlug({ slug });
  return {
    title: `my-site | ${modSlug}`,
    modSlug
  }
}

export default async function Page({ params }) {
  const { slug } = await params;
  const modSlug = modifySlug({ slug })
  return (
    <SomeOtherComponent modSlug={modSlug} />
  )
}