emissary/internal/agent/controller/registration/handler.go

75 lines
1.4 KiB
Go

package registration
import (
"embed"
"html/template"
"io/fs"
"net/http"
"sync"
"sync/atomic"
"github.com/pkg/errors"
"gitlab.com/wpetit/goweb/logger"
)
//go:embed templates/*.gotpl
var templates embed.FS
//go:embed public/*
var public embed.FS
type Handler struct {
status *atomic.Value
public http.Handler
templates *template.Template
init sync.Once
initErr error
}
// ServeHTTP implements http.Handler.
func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
h.init.Do(func() {
root, err := fs.Sub(public, "public")
if err != nil {
h.initErr = errors.WithStack(err)
return
}
h.public = http.FileServer(http.FS(root))
tmpl, err := template.ParseFS(templates, "templates/*.gotpl")
if err != nil {
h.initErr = errors.WithStack(err)
return
}
h.templates = tmpl
})
if h.initErr != nil {
logger.Error(r.Context(), "could not initialize handler", logger.E(h.initErr))
http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
return
}
switch r.URL.Path {
case "/":
h.serveIndex(w, r)
default:
h.public.ServeHTTP(w, r)
}
}
func (h *Handler) serveIndex(w http.ResponseWriter, r *http.Request) {
data := h.status.Load()
if err := h.templates.ExecuteTemplate(w, "index.html.gotpl", data); err != nil {
logger.Error(r.Context(), "could not render template", logger.E(errors.WithStack(err)))
return
}
}
var _ http.Handler = &Handler{}