AEM Graphql Last-Modified response header doesn't update when content is updated and published

[sgochipata1]

I have a graphql persisted query that pulls the content from AEM via graphql. When I change a content and publish, the updated content is shown in response body but the last-modified response header isn't updated reflect the content modified date

[SantoshSai]

Hi @sgochipata1,

This is expected behavior.

• The Last-Modified HTTP header is set by the GraphQL servlet / dispatcher cache layer, not by the actual content’s JCR modified date.

• By default, AEM’s persisted GraphQL queries use the query definition / persisted query file as the basis for cache metadata, not the underlying content nodes.

• When you publish new content:

  • The response body updates correctly (because the query result is re-evaluated).

  • But the Last-Modified header doesn’t reflect your content update, because AEM doesn’t automatically rebind that header to every JCR node’s lastModified property.

Here are what options/workarounds you have:

1. Enable ETag on the dispatcher/CDN layer so cache invalidation is based on the response body fingerprint, not JCR metadata.

2. Custom header with content metadata

   • Extend your persisted query endpoint to return a custom header (e.g., X-Content-LastModified) by looking up the max cq:lastModified (or your model’s date field) across the queried nodes.

   • This requires a Sling Filter or custom servlet wrapper.

3. Dispatcher/CDN cache invalidation

   • Instead of relying on Last-Modified, configure your publish/flush agents or GraphQL endpoint caching so that replication events invalidate cached responses.

   • This is the most common Adobe-recommended approach.

4. GraphQL response field

   • Add the lastModified property directly into your GraphQL schema model (using cq:lastModified from the fragment/page).

   • Then consumers can handle freshness inside the JSON body, rather than at the HTTP header level.