fix: work in progress fix for caching issues on catch all routes

Author: mrstork

src/run/handlers/cache.cts

@@ -137,11 +137,19 @@ export class NetlifyCacheHandler implements CacheHandlerForMultipleVersions {
   }
 
   private captureCacheTags(cacheValue: NetlifyIncrementalCacheValue | null, key: string) {
+    const requestContext = getRequestContext()
+
     if (!cacheValue) {
+      if (requestContext?.responseCacheTags) {
+        const cacheTags = [`_N_T_${key === '/index' ? '/' : encodeURI(key)}`]
+        requestContext.responseCacheTags = cacheTags
+
+        console.log('cache tags set:', cacheTags)
+      }
+
       return
     }
 
-    const requestContext = getRequestContext()
     // Bail if we can't get request context
     if (!requestContext) {
       return
@@ -420,7 +428,7 @@ export class NetlifyCacheHandler implements CacheHandlerForMultipleVersions {
         value,
       })
 
-      if (data?.kind === 'PAGE' || data?.kind === 'PAGES') {
+      // if (data?.kind === 'PAGE' || data?.kind === 'PAGES') {
         const requestContext = getRequestContext()
         if (requestContext?.didPagesRouterOnDemandRevalidate) {
           // encode here to deal with non ASCII characters in the key
@@ -441,7 +449,7 @@ export class NetlifyCacheHandler implements CacheHandlerForMultipleVersions {
             }),
           )
         }
-      }
+      // }
     })
   }
 

src/run/handlers/server.ts

@@ -133,7 +133,7 @@ export default async (
     }
 
     setCacheControlHeaders(response, request, requestContext, nextConfig)
-    setCacheTagsHeaders(response.headers, requestContext)
+    setCacheTagsHeaders(response.headers, request, requestContext)
     setVaryHeaders(response.headers, request, nextConfig)
     setCacheStatusHeader(response.headers, nextCache)
 

src/run/headers.ts

@@ -239,7 +239,6 @@ export const setCacheControlHeaders = (
       .log('NetlifyHeadersHandler.trailingSlashRedirect')
   }
 
-  const cacheControl = headers.get('cache-control')
   if (status === 404) {
     if (request.url.endsWith('.php')) {
       // temporary CDN Cache Control handling for bot probes on PHP files
@@ -260,6 +259,8 @@ export const setCacheControlHeaders = (
     }
   }
 
+  const cacheControl = headers.get('cache-control')
+
   if (
     cacheControl !== null &&
     ['GET', 'HEAD'].includes(request.method) &&
@@ -300,13 +301,20 @@ export const setCacheControlHeaders = (
   }
 }
 
-export const setCacheTagsHeaders = (headers: Headers, requestContext: RequestContext) => {
-  if (
-    requestContext.responseCacheTags &&
-    (headers.has('cache-control') || headers.has('netlify-cdn-cache-control'))
-  ) {
+export const setCacheTagsHeaders = (headers: Headers, request: Request, requestContext: RequestContext) => {
+  if (!headers.has('cache-control') && !headers.has('netlify-cdn-cache-control')) {
+    return
+  }
+
+  if (requestContext.responseCacheTags) {
     headers.set('netlify-cache-tag', requestContext.responseCacheTags.join(','))
+    return
   }
+
+  const key = new URL(request.url).pathname
+  const cacheTag = `_N_T_${key === '/index' ? '/' : encodeURI(key)}`
+  console.log('setCacheTagsHeaders', 'netlify-cache-tag', key)
+  headers.set('netlify-cache-tag', cacheTag)
 }
 
 /**

src/run/next.cts

@@ -106,7 +106,8 @@ export async function getMockedRequestHandler(...args: Parameters<typeof getRequ
             if (!file.isFallback) {
               const requestContext = getRequestContext()
               if (requestContext) {
-                requestContext.usedFsReadForNonFallback = true
+                // Causing caching for too many requests (e.g. api routes)
+                // requestContext.usedFsReadForNonFallback = true
               }
             }