generateSitemaps: Allow string values and not only numbers when generating multiple sitemaps

[ComeExploreCanada]

Goals

1. Backward compatibility with older websites
2. Flexible to generate sitemap files

Non-Goals

1. Does not address how generateSitemaps() output files in a out/sitemap directory.

It would be nice if app/sitemap.ts outputted files in the at the root level of out and if you wanted it to be in a out/sitemap directory you would do app/sitemap/sitemap.ts. But this is not part of this request. 😄

Background

My current site is a Next.js (pages Router) app and I am moving to (app Router) app. I would like this feature so websites can keep the same sitemap file names.

In my Next.js (pages Router) app I have the following structure:

public/sitemap.xml
public/sitemap_business.xml
public/sitemap_categories.xml
public/sitemap_communities.xml
public/sitemap_parks.xml
public/sitemap_products.xml

And Next.js outputs it to:

out/sitemap.xml
out/sitemap_business.xml
out/sitemap_categories.xml
out/sitemap_communities.xml
out/sitemap_parks.xml
out/sitemap_products.xml

Proposal

When generating multiple sitemaps with generateSitemaps() it would be nice to have the options to use a string values. Currently if you use a string value you get "Not Found" in the *.xml file(s).

The following app/sitemap.ts will output this folder/file structure:

out/sitemap/1.xml
out/sitemap/4.xml

// app/sitemap.ts

export async function generateSitemaps() {
  return [{ id: 1 }, { id: 4 }];
}

export default async function sitemap() {
  return [{ url: `https://example.com`, lastModified: '2023-05-17' }];
}

---

It would be great if app/sitemap.ts will output this folder/file structure:

out/sitemap/communities.xml
out/sitemap/parks.xml

// app/sitemap.ts

export async function generateSitemaps() {
  return [{ id: 'communities' }, { id: 'parks' }];
}

export default async function sitemap() {
  return [{ url: `https://example.com`, lastModified: '2023-05-17' }];
}