I am using Magento 2.4.3-p3 with PWA Venia on storefront and recently have observed incorrect headers i.e. it’s always no-cache, no-store & max-age=60.

I have checked the backend code and do not see any cacheable=false code in custom modules. I think it’s due to the upward.yml configuration (given below).

# This is a top-level object used to set values for the root `status`,
# `headers`, and `body` properties.
# It is the first branch in an abstract decision tree, which ultimately
# resolves to an object that contains values for its own 'status', 'headers',
# and 'body' properties.
# This object uses a ConditionalResolver to determine the object value based
# on the URL pattern in the request object.
veniaResponse:
    resolver: conditional
    when:
        # Requests to graphql/rest endpoints, the media library, and cache are
        # handled by the top-level 'veniaProxy' object, which is a ProxyResolver
        # that passes the request through to the backing Magento server.
        - matches: request.url.pathname
          pattern: '^/(graphql|rest|media)(/|$)'
          use: veniaProxy
        - matches: request.url.pathname
          pattern: '^/(robots.txt|favicon.ico|manifest.json)'
          use: staticFromRoot
        - matches: fileExtension
          pattern: '(js|json|png|jpg|gif|svg|ico|css|txt)'
          use: veniaStatic
    default: veniaAppShell

# A FileResolver for serving certain files directly from document root,
# even though they are published to the `static` folder in build assets.
staticFromRoot:
    inline:
        status: 200
        headers:
            resolver: inline
            inline:
                content-type: contentTypeFromExtension
                cache-control:
                    inline: public, max-age=604800
        body:
            resolver: file
            parse:
              inline: text
            encoding:
              inline: binary
            file:
                resolver: template
                engine: mustache
                provide:
                    filename: request.url.pathname
                template:
                    resolver: inline
                    inline: './venia-static/{{ filename }}'

contentTypeFromExtension:
    when:
        - matches: fileExtension
          pattern: '^ico$'
          use:
              inline: image/x-icon
        - matches: fileExtension
          pattern: '^txt$'
          use:
              inline: text/plain
        - matches: fileExtension
          pattern: '^json$'
          use:
              inline: application/json
    default:
        inline: text/html

# Contains the file extension--the part after the dot--of the URL path.
fileExtension:
    resolver: conditional
    when:
        - matches: request.url.pathname
          pattern: '.(.*)$'
          use: $match.$1
    default:
        inline: ''

# A ProxyResolver object that passes a request to the backend Magento
# server defined in the MAGENTO_BACKEND_URL environment variable.
# An UPWARD server infers this object as a ProxyResolver due to the presence
# of the 'target' property.
veniaProxy:
    resolver: proxy
    target: env.MAGENTO_BACKEND_URL
    # A local Magento install may have SSH configured and untrusted,
    # which is not a major concern for this one origin, especially if
    # containerized. Clients which require trust may proxy through UPWARD.
    ignoreSSLErrors:
      when:
          - matches: env.NODE_ENV
            pattern: 'production'
            use:
              inline: false
      default:
        inline: true

# Page type data for initial render
veniaPageType:
  resolver: inline
  inline:
    data:
      resolver: computed
      type:
        resolver: inline
        inline: pageType
      additional:
        - type: product
          fetch: '__typename,id'
        - type: cms_page
          fetch: 'identifier'
        - type: category
          fetch: 'uid'

# Nonce for page type inline script
veniaPageTypeNonce:
  resolver: inline
  inline:
    nonce:
      resolver: computed
      type:
        resolver: inline
        inline: pageTypeNonce

# Webpack chunks to preload on page based on page type
veniaWebpackChunks:
  resolver: inline
  inline:
    scripts:
      resolver: computed
      type:
        resolver: inline
        inline: webpackChunks

# The veniaAppShell object resolves to a response that returns server-side
# rendered HTML containing the PWA application shell.
# For SEO purposes, the appropriate meta tags in the HTML head element are also
# set based on information about the resource.
# This object uses properties in the top-level 'veniaResponse' object to return
# the appropriate response values.
veniaAppShell:
    resolver: inline
    inline:
        status:
            resolver: inline
            inline: 200
        headers:
            resolver: inline
            inline:
                content-type:
                    inline: text/html
                cache-control:
                    inline: s-maxage=60
        body:
          resolver: template
          engine: mustache
          provide:
            pageType: veniaPageType.data
            pageTypeNonce: veniaPageTypeNonce.nonce
            webpackChunks: veniaWebpackChunks.scripts
          template:
            resolver: file
            file:
              resolver: inline
              inline: './index.html'


# The veniaStatic object is a DirectoryResolver that allows access to the files
# inside the project's compiled './dist' directory.
veniaStatic:
    resolver: directory
    directory:
        resolver: inline
        inline: '.'

# These are no-ops at runtime; nothing refers to these context values in the
# rest of this file. They exist to declare that the files in the `./static`
# directory are required and should be copied into the build assets by the
# UpwardIncludePlugin. Since they are not directly mentioned elsewhere in this
# file or any other upward.yml file in the build, the UpwardIncludePlugin would
# fail to copy them if they were not mentioned here.

# The static directory includes files which don't need to be compiled.
# They are served by the `veniaStatic` DirectoryResolver, along with the
# bundles and other assets, but since that resolver serves the `.` dist
# directory, the UpwardIncludePlugin will not copy it to avoid circular
# dependency. TODO: This is kind of confusing.
veniaStaticIncludes:
    resolver: directory
    directory:
        resolver: inline
        inline: './venia-static'
status: veniaResponse.status
headers: veniaResponse.headers
body: veniaResponse.body

Upon further debugging, I observed that it always uses default veniaAppShell, which is fine as the content shouldn’t be cached for bots. But what about actual users? But shouldn’t it use staticFromRoot?

Need help here, how do I fix the headers? Because due to this Varnish isn’t caching.