display yt-dlp version, multiple downloads enabled.

code refactoring
preparations for optimistic ui updates for new downloads

server/rest/container.go

@@ -26,6 +26,7 @@ func ApplyRouter(db *sql.DB, mdb *internal.MemoryDB, mq *internal.MessageQueue)
 		}
 		r.Post("/exec", h.Exec())
 		r.Get("/running", h.Running())
+		r.Get("/version", h.GetVersion())
 		r.Post("/cookies", h.SetCookies())
 		r.Post("/template", h.AddTemplate())
 		r.Get("/template/all", h.GetTemplates())

server/rest/handlers.go

@@ -158,3 +158,21 @@ func (h *Handler) DeleteTemplate() http.HandlerFunc {
 		}
 	}
 }
+
+func (h *Handler) GetVersion() http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		defer r.Body.Close()
+
+		w.Header().Set("Content-Type", "application/json")
+
+		version, err := h.service.GetVersion(r.Context())
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+
+		if err := json.NewEncoder(w).Encode(version); err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+		}
+	}
+}

server/rest/service.go

@@ -6,8 +6,11 @@ import (
 	"errors"
 	"log/slog"
 	"os"
+	"os/exec"
+	"time"
 
 	"github.com/google/uuid"
+	"github.com/marcopeocchi/yt-dlp-web-ui/server/config"
 	"github.com/marcopeocchi/yt-dlp-web-ui/server/internal"
 )
 
@@ -118,3 +121,23 @@ func (s *Service) DeleteTemplate(ctx context.Context, id string) error {
 
 	return err
 }
+
+func (s *Service) GetVersion(ctx context.Context) (string, error) {
+	ch := make(chan string, 1)
+
+	c, cancel := context.WithTimeout(ctx, time.Second*10)
+	defer cancel()
+
+	cmd := exec.CommandContext(c, config.Instance().DownloaderPath, "--version")
+	go func() {
+		stdout, _ := cmd.Output()
+		ch <- string(stdout)
+	}()
+
+	select {
+	case <-c.Done():
+		return "", errors.New("requesting yt-dlp version took too long")
+	case res := <-ch:
+		return res, nil
+	}
+}