feat: use Varnish only for web:80, remove novarnish subdomains, fixes #32

[stasadev]

The Issue

• Redirect requests on web_extra_exposed_ports to novarnish.DDEV_PROJECT.DDEV_TLD #32

How This PR Solves The Issue

Varnish should run only for web:80, not for all ports.

This PR changes the logic to route web:80 through Varnish, while leaving everything else (Mailpit, web_extra_exposed_ports) unchanged.

This removes the need for novarnish.* subdomains.

Manual Testing Instructions

Prepare project:

mkdir varnish-test && cd varnish-test
printf "<?php\necho 'index' . PHP_EOL;\n" >index.php
ddev config --auto
mkdir -p php-extra
printf "<?php\necho 'php-extra' . PHP_EOL;\n" >php-extra/index.php
cat >>.ddev/config.yaml <<'EOF'
web_extra_daemons:
    - name: "php-extra"
      command: "php -S 0.0.0.0:20080"
      directory: /var/www/html/php-extra
web_extra_exposed_ports:
    - name: "php-extra"
      container_port: 20080
      http_port: 20080
      https_port: 20443
EOF

Install add-on:

ddev add-on get https://github.com/ddev/ddev-varnish/tarball/refs/pull/46/head
ddev restart

And test it:

# All the URLs should work without any redirects:
ddev launch
ddev mailpit
ddev launch :20443

Only this url should have Varnish headers:

$ ddev exec 'curl -I $DDEV_PRIMARY_URL'
HTTP/2 200 
accept-ranges: bytes
age: 0
content-type: text/html; charset=UTF-8
date: Mon, 22 Sep 2025 13:09:22 GMT
server: nginx
vary: Accept-Encoding
via: 1.1 varnish (Varnish/6.0)
x-varnish: 2
content-length: 6

Mailpit: no Varnish headers:

$ ddev exec 'curl -I $DDEV_PRIMARY_URL:8026'
HTTP/2 405 
date: Mon, 22 Sep 2025 13:10:09 GMT

web_extra_exposed_ports: no Varnish headers:

$ ddev exec 'curl -I $DDEV_PRIMARY_URL:20443'
HTTP/2 200 
content-type: text/html; charset=UTF-8
date: Mon, 22 Sep 2025 13:11:00 GMT
host: varnish-test.ddev.site:20443
x-powered-by: PHP/8.3.25

Automated Testing Overview

I added test coverage for everything.

Release/Deployment Notes

This should be released as major v1.0.0.

[stasadev]

@jedubois, please review, it should cover exactly the issue you reported.