at-container-registry/pkg/appview/handlers/errors.go

package handlers

import (
	"net/http"
)

// NotFoundHandler handles 404 errors
type NotFoundHandler struct {
	BaseUIHandler
}

func (h *NotFoundHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	RenderNotFound(w, r, &h.BaseUIHandler)
}

// RenderNotFound renders the 404 page template.
// Use this from other handlers when a resource is not found.
func RenderNotFound(w http.ResponseWriter, r *http.Request, h *BaseUIHandler) {
	w.WriteHeader(http.StatusNotFound)

	meta := NewPageMeta(
		"404 - Lost at Sea | "+h.ClientShortName,
		"Page not found - the requested resource doesn't exist on "+h.ClientShortName,
	).WithRobots("noindex").
		WithSiteName(h.ClientShortName)

	data := struct {
		PageData
		Meta *PageMeta
	}{
		PageData: NewPageData(r, h),
		Meta:     meta,
	}

	if err := h.Templates.ExecuteTemplate(w, "404", data); err != nil {
		http.Error(w, "Page not found", http.StatusNotFound)
	}
}