perf: several dragged items cross to another place as one tar stream; older agents get them one by one

internal/server/ship.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"encoding/json"
 	"net/http"
+	"path"
 	"strconv"
 	"strings"
 	"sync"
@@ -119,6 +120,8 @@ type shipReq struct {
 	// file pane (its connection id); To is still the agent holding ToConn.
 	FromConn string `json:"from_conn"`
 	ToConn   string `json:"to_conn"`
+	// More: other things of Src's folder sent along, under their own names.
+	More []string `json:"more"`
 }
 
 // POST /api/panel/agents/{id}/fs/ship - start sending; the answer names the
@@ -214,7 +217,27 @@ func oldAgent(res proto.TaskResult) proto.TaskResult {
 }
 
 func (s *Server) ship1(ctx context.Context, j *shipJob, from string, q shipReq) proto.TaskResult {
-	args := proto.FSShipArgs{Src: q.Src, Name: q.Name, Dir: q.Dir, Conflict: q.Conflict, Job: j.id}
+	if len(q.More) > 0 && !s.shipsSeveral(from, q) {
+		// One at a time: an SSH address, or an agent from before 0.2.0.
+		var last proto.TaskResult
+		done, skipped := 0, 0
+		for i, p := range append([]string{q.Src}, q.More...) {
+			one := q
+			one.Src, one.More = p, nil
+			if i > 0 {
+				one.Name = path.Base(path.Clean(p))
+			}
+			if last = s.ship1(ctx, j, from, one); !last.OK {
+				return last
+			}
+			var d struct{ Done, Skipped int }
+			_ = json.Unmarshal(last.Data, &d)
+			done, skipped = done+d.Done, skipped+d.Skipped
+		}
+		data, _ := json.Marshal(map[string]int{"done": done, "skipped": skipped})
+		return proto.TaskResult{OK: true, Data: data}
+	}
+	args := proto.FSShipArgs{Src: q.Src, Name: q.Name, Dir: q.Dir, Conflict: q.Conflict, Job: j.id, More: q.More}
 	if q.SSH != nil {
 		args.SSH, args.Move = q.SSH, q.Move
 		res, err := s.waitTask(ctx, from, proto.TaskFSShipOut, args, xferTimeout)
@@ -267,17 +290,19 @@ func (s *Server) ship1(ctx context.Context, j *shipJob, from string, q shipReq)
 		return out
 	}
 	if q.Move {
-		task, del := proto.TaskFSDelTree, any(proto.FSPathArgs{Path: q.Src})
-		if q.FromConn != "" {
-			raw, _ := json.Marshal(proto.FSPathArgs{Path: q.Src})
-			task, del = proto.TaskSSHFSOp, proto.SSHFSArgs{Conn: q.FromConn, Op: "deltree", Args: raw}
-		}
-		res, err := s.waitTask(ctx, from, task, del, fsTaskTimeout)
-		if err == nil && !res.OK {
-			err = errText(res.Error)
-		}
-		if err != nil {
-			return proto.TaskResult{Error: "отправлено, но здесь не удалилось: " + err.Error()}
+		for _, p := range append([]string{q.Src}, q.More...) {
+			task, del := proto.TaskFSDelTree, any(proto.FSPathArgs{Path: p})
+			if q.FromConn != "" {
+				raw, _ := json.Marshal(proto.FSPathArgs{Path: p})
+				task, del = proto.TaskSSHFSOp, proto.SSHFSArgs{Conn: q.FromConn, Op: "deltree", Args: raw}
+			}
+			res, err := s.waitTask(ctx, from, task, del, fsTaskTimeout)
+			if err == nil && !res.OK {
+				err = errText(res.Error)
+			}
+			if err != nil {
+				return proto.TaskResult{Error: "отправлено, но здесь не удалилось: " + err.Error()}
+			}
 		}
 	}
 	// The receiver's count: what it put down and what it kept as it was.
@@ -434,3 +459,38 @@ func (s *Server) handleRelayGet(w http.ResponseWriter, r *http.Request) {
 	}
 	_, _ = w.Write(data)
 }
+
+// shipsSeveral: both agents take several things in one stream (0.2.0 on).
+func (s *Server) shipsSeveral(from string, q shipReq) bool {
+	if q.SSH != nil {
+		return false
+	}
+	for _, id := range []string{from, q.To} {
+		a, _ := s.db.GetAgent(id)
+		if a == nil || !versionAtLeast(a.Version, "0.2.0") {
+			return false
+		}
+	}
+	return true
+}
+
+// versionAtLeast: version v (dotted numbers) is min or newer; anything else
+// is taken for older.
+func versionAtLeast(v, min string) bool {
+	a, b := strings.Split(v, "."), strings.Split(min, ".")
+	for i := range b {
+		var x, y int
+		if i < len(a) {
+			n, err := strconv.Atoi(a[i])
+			if err != nil {
+				return false
+			}
+			x = n
+		}
+		y, _ = strconv.Atoi(b[i])
+		if x != y {
+			return x > y
+		}
+	}
+	return true
+}