download.md: append ?action=download to archive download links

[Swatantra-66]

Summary

Release artifact links in the Archive column of download.md use {{ release.artifact-root }}, which points to Apache's mirror selector (https://www.apache.org/dyn/closer.lua/...). Without the ?action=download parameter, clicking OS or Apps downloads navigates users to an HTML mirror-picker webpage instead of directly downloading the release tarball.

In accordance with official ASF Release Download Pages Policy, this PR appends ?action=download to source-os-dist and source-app-dist links in the release artifacts table.

Fixes #189

Impact

• Direct clicks on OS and Apps links under the Archive column on nuttx.apache.org/download/ will now immediately trigger the download rather than showing a mirror selection page.
• Fully adheres to Apache Software Foundation distribution guidelines.

Testing

Verified URL response headers via curl -I:

• Current release (13.1.0):
  https://www.apache.org/dyn/closer.lua/nuttx/13.1.0/apache-nuttx-13.1.0.tar.gz?action=download
  Returns HTTP/1.1 302 Found with Location: https://dlcdn.apache.org/nuttx/13.1.0/apache-nuttx-13.1.0.tar.gz.
• Archived incubator release (10.0.1):
  https://www.apache.org/dyn/closer.lua/incubator/nuttx/10.0.1/apache-nuttx-10.0.1-incubating.tar.gz?action=download
  Returns HTTP/1.1 302 Found with Location: https://archive.apache.org/dist/incubator/nuttx/10.0.1/....
• Direct archive link (9.1.0):
  https://archive.apache.org/dist/incubator/nuttx/9.1.0/apache-nuttx-9.1.0-incubating.tar.gz?action=download
  Returns HTTP/1.1 200 OK (query parameter gracefully ignored by archive server).

[cederom]

Thank you @Swatantra-66 :-)

How about we use https://downloads.apache.org/nuttx/13.1.0/apache-nuttx-13.1.0.tar.gz and https://downloads.apache.org/nuttx/13.1.0/apache-nuttx-apps-13.1.0.tar.gz so all links use the same https://downloads.apache.org/nuttx/ base? :-)

Do you know what is the difference between https://downloads.apache.org/ and https://dlcdn.apache.org/ ? Does downloads redirect to dlcdn? I guess it is better to use dlcdn right? :-)

[Swatantra-66]

Hi @cederom!

Here is the difference between them and why closer.lua with ?action=download is the ASF-recommended standard:

1. downloads.apache.org is the master ASF origin server. It hosts the source of truth for current releases, KEYS, signatures (.asc), and hashes (.sha512). However, ASF Infra guidelines explicitly state that release tarballs should not be served directly to the public from downloads.apache.org to protect the origin server's bandwidth (it does not redirect to CDN; it serves the full ~140MB file directly).

2. dlcdn.apache.org is the global CDN (backed by Varnish/Fastly edge caches), which caches active release tarballs for fast global distribution. However, dlcdn only keeps current active releases (older archived releases get removed).

3. closer.lua with ?action=download gives the best of both worlds:

   • For current releases (like 13.1.0), it issues an immediate HTTP 302 redirect directly to dlcdn.apache.org without rendering the HTML mirror page.
   • For older/incubator releases (like 10.0.1 or 9.1.1), it automatically issues an HTTP 302 redirect to archive.apache.org.
   • It complies 100% with the official ASF Release Download Policy, which mandates projects use the closer.lua dispatcher for release downloads.

So closer.lua?...?action=download ensures users get direct one-click downloads via dlcdn, while staying fully compliant with ASF infra rules and keeping older release links working!

[cederom]

Thank you @Swatantra-66 :-)