oh I just found now :

https://nextjs.org/docs/app/api-reference/functions/permanentRedirect

you can use this one: https://nextjs.org/docs/app/api-reference/functions/redirect

ah lol

yes but its a 301 code

308 rather

ah got it 👍

🙂

good job!

what do you think of this :

export default async function CatList({ params: { catSlug } }: catSlugProps) {
  // on récupère le slug de la catégorie
  // celui-ci contient un id
  // Sépare la chaîne au tiret et prend le premier élément
  const potentialId = catSlug.split("-")[0];

  // on a maintenant l'id de la catégorie de l'url
  // on doit vérifier :

  // 1) qu'il existe et qu'il s'agit bien d'un nombre
  let catId = null;

  // si potentialId est null ou undefined
  if (!potentialId) {
    notFound();
  } else {
    catId = parseInt(potentialId, 10);
    if (isNaN(catId)) {
      // si catId n'est pas un nombre
      notFound();
    }
  }

  // 2) que la catégorie existe bien
  const askedCategory = await prisma.category.findUnique({
    where: { id: catId },
  });

  if (!askedCategory) {
    notFound();
  }

  // 3) que le slug n'est pas différent de celui en base de données
  // on récupère le slug en base de données
  const slugInDatabase = askedCategory.slug;
  if (slugInDatabase !== catSlug) {
    // si le slug est différent
    // on redirige vers la bonne url
    permanentRedirect(`/modele/${slugInDatabase}`);
  }

  return (
    <>
      <p>Rendering here.</p>
    </>
  );
}

sorry comments in french 🙂

that looks good for me. If you need the slug only for SEO, you can use generateMetaData to fetch only for the meta tags. Because I think you might fetch again at "/modele/${slugInDatabase}" right?

yes

but now it's an infinite loop lol, let me take a look

haha yea xD

permanentRedirect(/modele/${catId}-${slugInDatabase});

what about only one page?

how ?

like push the user directly to the modele/..

that's what I did ?

We done:
push the user to one page, fetch the product -> redirect -> fetch the product on other page

I mean:
push the user to the product page, fetch the product

ok I'm lost... lol

just to be clear, let me explain the code

this page is supposed to load subcategories thanks to the slug from the params

- the slug contains the catId, so we extracted it
- then we checked if the catId exists in the database
- then we compare the slug params with the slug in the database : if it's not the same, we redirect to the right slug :

example :

12-apple-macbook => 12-apple-macbook-air

yea

but now I'm struggling with an infinite loop lol

yes, create only one page is the key, that I would use to break the loop

I don't understand, for me , I hav eonly one page

ok, for me you have 2 page.
Page 1 (CatList): this one: https://nextjs-forum.com/post/1179504824627245117#message-1179506347830681600
Page 2: "/modele/someslug"
So if we can compare both, your will be able to break it

- page 1 is : /app/modele/[catSlug]/page.tsx

-page 2 is the same page as page 1 : /app/modele/[catSlug]/page.tsx

lol

ah oh, then I misunderstood that

why do we redirect? 🤔
SEO can be done in meta tags. So, we don't redirect because of SEO. Why do we redirect?

we redirect because of update of the slug

to avoid duplicate content

to avoid 2 urls of the same page

12-apple-macbook is the same page as 12-apple-macbook-air

we d'ont want to have 2 results in Google pointing to the same content

are you creating a sitemap.xml for google?

not now maybe later of course

with the sitemap you can remove duplicates. So while generating the xml just fetch the one. There won't be any loop

but that's maybe not the best solution.

oh I found

I have to remove the catId before comparing it to the slug in database

that's why always : slugInDatabase == catSlug

infinite loop

permanentRedirect(/modele/${catId}-${slugInDatabase}); is always launched

great to hear that 👍

thanks for your time