Preview deployments incorrectly inherit www-redirect

[jrm402]

To Reproduce

1. Create an application. Enable redirect-to-www.
2. Enable preview deployments.
3. Create a new PR to trigger a preview deployment.
4. Once deployed, the preview URL will force a redirect to ``www.`.

Current vs. Expected behavior

Because preview URLs are wildcard subdomains, I would expect the www redirect middleware to be left off. It is incorrectly inherited from the main deployment settings.

Provide environment information

Operating System:
  OS: Debian 13
  Arch: arm64
Dokploy version: v0.27.1
VPS Provider: Hostinger
What applications/services are you trying to deploy? Nextjs

Which area(s) are affected? (Select all that apply)

Traefik

Are you deploying the applications where Dokploy is installed or on a remote server?

Same server where Dokploy is installed

Additional context

No response

Will you send a PR to fix it?

Maybe, need help

[xXMrNidaXx]

Good catch. This is a classic middleware inheritance bug in Traefik dynamic configuration.

Root Cause

The redirect-to-www middleware is likely being attached at the service or router level without checking whether the host is a preview deployment subdomain.

Fix Approach

In the Traefik dynamic config generation (likely in the deployment service), you need to conditionally exclude the www-redirect middleware for preview routers:

// Pseudocode - adjust to actual Dokploy codebase
func generateRouterConfig(deployment Deployment, isPreview bool) TraefikRouter {
    middlewares := []string{}
    
    for _, m := range deployment.Middlewares {
        // Skip www-redirect for preview deployments
        if isPreview && m.Type == "redirect-to-www" {
            continue
        }
        middlewares = append(middlewares, m.Name)
    }
    
    return TraefikRouter{
        Rule:        buildHostRule(deployment, isPreview),
        Middlewares: middlewares,
        // ...
    }
}

Alternative: Host-Aware Middleware

If modifying the router generation is complex, you could make the www-redirect middleware itself host-aware:

# In Traefik dynamic config
http:
  middlewares:
    redirect-www:
      redirectRegex:
        # Only match non-preview domains
        regex: "^https?://(?!.*-preview\\.)([^w][^w][^w]\\.|[^.]+\\.)example\\.com(.*)"
        replacement: "https://www.${1}example.com${2}"

But the cleaner solution is excluding the middleware at generation time.

Files to Look At

Search for where preview deployment Traefik labels/configs are generated — should be near the deployment service or Docker Compose generator. The fix is a one-liner conditional.

Happy to help review a PR if you go for it!