feat: skip empty sitemaps WIP

src/runtime/server/composables/defineSitemapEventHandler.ts

@@ -2,4 +2,4 @@ import { defineEventHandler } from 'h3'
 import type { EventHandlerRequest, EventHandlerResponse } from 'h3'
 import type { SitemapUrlInput } from '../../types'
 
-export const defineSitemapEventHandler: typeof defineEventHandler<EventHandlerRequest, EventHandlerResponse<SitemapUrlInput[]>> = defineEventHandler
+export const defineSitemapEventHandler: typeof defineEventHandler<EventHandlerRequest, EventHandlerResponse<{ skip: number } | (SitemapUrlInput[])>> = defineEventHandler

src/runtime/server/index.ts

@@ -0,0 +1,2 @@
+export { defineSitemapEventHandler } from './composables/defineSitemapEventHandler'
+export { asSitemapUrl } from './composables/asSitemapUrl'

src/runtime/server/routes/__sitemap__/debug.ts

@@ -1,4 +1,5 @@
 import { defineEventHandler } from 'h3'
+import { useStorage } from 'nitropack/runtime'
 import type { SitemapDefinition } from '../../../types'
 import { useSitemapRuntimeConfig } from '../../utils'
 import {
@@ -8,7 +9,7 @@
 } from '../../sitemap/urlset/sources'
 import { useNitroOrigin } from '#imports'
 
 export default defineEventHandler(async (e) => {
   const _runtimeConfig = useSitemapRuntimeConfig()
   const { sitemaps: _sitemaps } = _runtimeConfig
   const runtimeConfig = { ..._runtimeConfig }
@@ -24,7 +25,10 @@
       sources: await resolveSitemapSources(await childSitemapSources(_sitemaps[s])),
     }
   }
+  const cacheKeys = await useStorage().keys('cache:sitemap')
+  const cacheFiles = await Promise.all(cacheKeys.map(async k => ({ key: k, val: await useStorage().get(k) })))
   return {
+    cache: cacheFiles,
     nitroOrigin,
     sitemaps,
     runtimeConfig,

src/runtime/server/sitemap/builder/sitemap-index.ts

@@ -1,6 +1,7 @@
 import { defu } from 'defu'
 import { joinURL } from 'ufo'
 import type { NitroApp } from 'nitropack/types'
+import { useStorage } from 'nitropack/runtime'
 import type {
   ModuleRuntimeConfig,
   NitroUrlResolvers,
@@ -58,10 +59,16 @@ export async function buildSitemapIndex(resolvers: NitroUrlResolvers, runtimeCon
     })
   }
   else {
+    const host = new URL(resolvers.canonicalUrlResolver('/')).hostname
+    const cacheKey = `cache:sitemap:${host}:skip.json`
+    const currStats = ((await useStorage().get(cacheKey)) || {}) as Record<string, number>
     for (const sitemap in sitemaps) {
       if (sitemap !== 'index') {
-        // user provided sitemap config
-        chunks[sitemap] = chunks[sitemap] || { urls: [] }
+        // automatically hide sitemap if it's empty
+        if (!(sitemap in currStats) || !currStats[sitemap]) {
+          // user provided sitemap config
+          chunks[sitemap] = chunks[sitemap] || { urls: [] }
+        }
       }
     }
   }

src/runtime/server/sitemap/builder/sitemap.ts

@@ -176,7 +176,7 @@ export function resolveSitemapEntries(sitemap: SitemapDefinition, urls: SitemapU
   return _urls
 }
 
-export async function buildSitemapUrls(sitemap: SitemapDefinition, resolvers: NitroUrlResolvers, runtimeConfig: ModuleRuntimeConfig, nitro?: NitroApp) {
+export async function buildSitemapUrls(sitemap: SitemapDefinition, resolvers: NitroUrlResolvers, runtimeConfig: ModuleRuntimeConfig, nitro?: NitroApp): Promise<{ skip: number } | ResolvedSitemapUrl[]> {
   // 0. resolve sources
   // 1. normalise
   // 2. filter
@@ -225,6 +225,17 @@ export async function buildSitemapUrls(sitemap: SitemapDefinition, resolvers: Ni
   const sourcesInput = sitemap.includeAppSources ? await globalSitemapSources() : []
   sourcesInput.push(...await childSitemapSources(sitemap))
   const sources = await resolveSitemapSources(sourcesInput, resolvers.event)
+  let skipTime = 0
+  for (const source of sources) {
+    if (source._skip) {
+      skipTime = Math.max(skipTime, source._skip)
+    }
+  }
+  if (skipTime > 0) {
+    return {
+      skip: skipTime,
+    }
+  }
   const resolvedCtx: SitemapInputCtx = {
     urls: sources.flatMap(s => s.urls),
     sitemapName: sitemap.sitemapName,

src/runtime/server/sitemap/nitro.ts

@@ -2,6 +2,7 @@ import { getQuery, setHeader, createError } from 'h3'
 import type { H3Event } from 'h3'
 import { fixSlashes } from 'nuxt-site-config/urls'
 import { defu } from 'defu'
+import { useStorage, cachedFunction } from 'nitropack/runtime'
 import type {
   ModuleRuntimeConfig,
   NitroUrlResolvers,
@@ -50,6 +51,17 @@ export async function createSitemap(event: H3Event, definition: SitemapDefinitio
   }
   const resolvers = useNitroUrlResolvers(event)
   let sitemapUrls = await buildSitemapUrls(definition, resolvers, runtimeConfig, nitro)
+  if (typeof sitemapUrls === 'object' && sitemapUrls.skip) {
+    const host = new URL(resolvers.canonicalUrlResolver('/')).hostname
+    const cacheKey = `cache:sitemap:${host}:skip.json`
+    const currStats = ((await useStorage().get(cacheKey)) || {}) as Record<string, boolean>
+    currStats[sitemapName] = {
+
+    }
+    await useStorage().set(cacheKey, currStats)
+    // still render
+    sitemapUrls = []
+  }
 
   const routeRuleMatcher = createNitroRouteRuleMatcher()
   const { autoI18n } = runtimeConfig

src/runtime/server/sitemap/urlset/sources.ts

@@ -51,16 +51,23 @@ export async function fetchDataSource(input: SitemapSourceBase | SitemapSourceRe
         error: 'Received HTML response instead of JSON',
       }
     }
+    let _skip: false | number = false
     let urls = []
     if (typeof res === 'object') {
-      urls = res.urls || res
+      if (res.skip) {
+        _skip = res.skip as number
+      }
+      else {
+        urls = res.urls || res
+      }
     }
     else if (typeof res === 'string' && parseURL(url).pathname.endsWith('.xml')) {
       // fast pass XML extract all loc data, let's use
       urls = extractSitemapXML(res)
     }
     return {
       ...input,
+      _skip,
       context,
       timeTakenMs,
       urls: urls as SitemapUrlInput[],

src/runtime/types.ts

@@ -179,6 +179,10 @@ export interface SitemapSourceBase {
   fetch?: string | [string, FetchOptions]
   urls?: SitemapUrlInput[]
   sourceType?: 'app' | 'user'
+  /**
+   * @internal
+   */
+  _skip?: false | number
 }
 export interface SitemapSourceResolved extends Omit<SitemapSourceBase, 'urls'> {
   urls: SitemapUrlInput[]

test/fixtures/basic/nuxt.config.ts

@@ -24,5 +24,20 @@ export default defineNuxtConfig({
     autoLastmod: false,
     credits: false,
     debug: true,
+    sitemaps: {
+      foo: {
+        sources: ['/api/sitemap/foo'],
+        defaults: {
+          changefreq: 'weekly',
+          priority: 0.7,
+        },
+      },
+      bar: {
+        sources: ['/api/sitemap/bar'],
+      },
+      empty: {
+        sources: ['/api/sitemap/empty'],
+      },
+    },
   },
 })

test/fixtures/basic/server/api/sitemap/empty.ts

@@ -0,0 +1,8 @@
+import { defineSitemapEventHandler } from '#sitemap/server'
+
+export default defineSitemapEventHandler(async () => {
+  await new Promise(resolve => setTimeout(resolve, 0))
+  return {
+    skip: 120_000,
+  }
+})

test/integration/multi/endpoints.ts

@@ -19,6 +19,9 @@ await setup({
         bar: {
           sources: ['/api/sitemap/bar'],
         },
+        empty: {
+          sources: ['/api/sitemap/empty'],
+        },
       },
     },
   },