fix(taildrop): restore incoming file progress notifications

The io.Copy in PutFile was writing directly to wc, bypassing the
incomingFile wrapper whose Write method increments f.copied and fires
a throttled sendFileNotify on progress. As a result, notifyIncomingFiles
on the JS side only ever fired once (on completion) with received=0,
making progress UI impossible. The original inFile wrapping was lost
during the Android SAF refactor.

Also surface the PartialFile.Done flag through jsIncomingFile so JS can
distinguish the final "transfer complete" notification from in-progress
updates.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

cmd/tsconnect/wasm/taildrop.go

@@ -23,8 +23,11 @@ import (
 
 	"tailscale.com/client/tailscale/apitype"
 	"tailscale.com/feature/taildrop"
+	"tailscale.com/ipn"
 	"tailscale.com/ipn/ipnlocal"
 	"tailscale.com/tailcfg"
+	"tailscale.com/util/progresstracking"
+	"tailscale.com/util/rands"
 )
 
 // Compile-time check that jsFileOps implements taildrop.FileOps.
@@ -78,7 +81,8 @@ func (i *jsIPN) listFileTargets() js.Value {
 	})
 }
 
-// sendFile sends data as filename to the peer identified by stableNodeID.
+// sendFile sends data as filename to the peer identified by stableNodeID,
+// reporting progress via notifyOutgoingFiles callbacks roughly once per second.
 func (i *jsIPN) sendFile(stableNodeID, filename string, data js.Value) js.Value {
 	return makePromise(func() (any, error) {
 		ext, err := i.taildropExt()
@@ -105,20 +109,46 @@ func (i *jsIPN) sendFile(stableNodeID, filename string, data js.Value) js.Value
 		}
 		b := make([]byte, data.Get("byteLength").Int())
 		js.CopyBytesToGo(b, data)
-		req, err := http.NewRequest("PUT", dstURL.String()+"/v0/put/"+url.PathEscape(filename), bytes.NewReader(b))
+
+		outgoing := &ipn.OutgoingFile{
+			ID:           rands.HexString(30),
+			PeerID:       tailcfg.StableNodeID(stableNodeID),
+			Name:         filename,
+			DeclaredSize: int64(len(b)),
+			Started:      time.Now(),
+		}
+		updates := map[string]*ipn.OutgoingFile{outgoing.ID: outgoing}
+
+		// Report final state (success or failure) when the function returns.
+		var sendErr error
+		defer func() {
+			outgoing.Finished = true
+			outgoing.Succeeded = sendErr == nil
+			ext.UpdateOutgoingFiles(updates)
+		}()
+
+		body := progresstracking.NewReader(bytes.NewReader(b), time.Second, func(n int, _ error) {
+			outgoing.Sent = int64(n)
+			ext.UpdateOutgoingFiles(updates)
+		})
+
+		req, err := http.NewRequest("PUT", dstURL.String()+"/v0/put/"+url.PathEscape(filename), body)
 		if err != nil {
+			sendErr = err
 			return nil, err
 		}
 		req.ContentLength = int64(len(b))
 		client := &http.Client{Transport: i.lb.Dialer().PeerAPITransport()}
 		resp, err := client.Do(req)
 		if err != nil {
+			sendErr = err
 			return nil, err
 		}
 		defer resp.Body.Close()
 		if resp.StatusCode != http.StatusOK && resp.StatusCode != http.StatusCreated {
-			body, _ := io.ReadAll(resp.Body)
-			return nil, fmt.Errorf("send file: %s: %s", resp.Status, bytes.TrimSpace(body))
+			respBody, _ := io.ReadAll(resp.Body)
+			sendErr = fmt.Errorf("send file: %s: %s", resp.Status, bytes.TrimSpace(respBody))
+			return nil, sendErr
 		}
 		return nil, nil
 	})

cmd/tsconnect/wasm/wasm_js.go

@@ -388,12 +388,52 @@ func (i *jsIPN) run(jsCallbacks js.Value) {
 				log.Printf("Could not generate JSON netmap: %v", err)
 			}
 		}
-		if n.Prefs.Valid() {
+		if n.Prefs != nil && n.Prefs.Valid() {
 			jsCallbacks.Call("notifyExitNode", string(n.Prefs.ExitNodeID()))
 		}
 		if n.BrowseToURL != nil {
 			jsCallbacks.Call("notifyBrowseToURL", *n.BrowseToURL)
 		}
+		if n.FilesWaiting != nil {
+			jsCallbacks.Call("notifyFilesWaiting")
+		}
+		if n.IncomingFiles != nil {
+			files := make([]jsIncomingFile, len(n.IncomingFiles))
+			for i, f := range n.IncomingFiles {
+				files[i] = jsIncomingFile{
+					Name:         f.Name,
+					Started:      f.Started.UnixMilli(),
+					DeclaredSize: f.DeclaredSize,
+					Received:     f.Received,
+					Done:         f.Done,
+				}
+			}
+			if b, err := json.Marshal(files); err == nil {
+				jsCallbacks.Call("notifyIncomingFiles", string(b))
+			} else {
+				log.Printf("could not marshal IncomingFiles: %v", err)
+			}
+		}
+		if n.OutgoingFiles != nil {
+			files := make([]jsOutgoingFile, len(n.OutgoingFiles))
+			for i, f := range n.OutgoingFiles {
+				files[i] = jsOutgoingFile{
+					ID:           f.ID,
+					PeerID:       string(f.PeerID),
+					Name:         f.Name,
+					Started:      f.Started.UnixMilli(),
+					DeclaredSize: f.DeclaredSize,
+					Sent:         f.Sent,
+					Finished:     f.Finished,
+					Succeeded:    f.Succeeded,
+				}
+			}
+			if b, err := json.Marshal(files); err == nil {
+				jsCallbacks.Call("notifyOutgoingFiles", string(b))
+			} else {
+				log.Printf("could not marshal OutgoingFiles: %v", err)
+			}
+		}
 	})
 
 	go func() {
@@ -921,6 +961,29 @@ func (w termWriter) Write(p []byte) (n int, err error) {
 	return len(p), nil
 }
 
+// jsIncomingFile is the JSON representation of an in-progress inbound file
+// transfer sent to the notifyIncomingFiles callback.
+type jsIncomingFile struct {
+	Name         string `json:"name"`
+	Started      int64  `json:"started"`      // Unix milliseconds; use new Date(started) in JS
+	DeclaredSize int64  `json:"declaredSize"` // -1 if unknown
+	Received     int64  `json:"received"`     // bytes received so far
+	Done         bool   `json:"done"`         // true once the file has been fully received
+}
+
+// jsOutgoingFile is the JSON representation of an outgoing file transfer
+// sent to the notifyOutgoingFiles callback.
+type jsOutgoingFile struct {
+	ID           string `json:"id"`
+	PeerID       string `json:"peerID"`
+	Name         string `json:"name"`
+	Started      int64  `json:"started"`      // Unix milliseconds
+	DeclaredSize int64  `json:"declaredSize"` // -1 if unknown
+	Sent         int64  `json:"sent"`         // bytes sent so far
+	Finished     bool   `json:"finished"`
+	Succeeded    bool   `json:"succeeded"` // only meaningful when finished
+}
+
 type jsNetMap struct {
 	Self      jsNetMapSelfNode   `json:"self"`
 	Peers     []jsNetMapPeerNode `json:"peers"`

feature/taildrop/ext.go

@@ -418,6 +418,13 @@ func (e *Extension) taildropTargetStatus(p tailcfg.NodeView, nb ipnext.NodeBacke
 	return ipnstate.TaildropTargetAvailable
 }
 
+// UpdateOutgoingFiles updates the tracked set of outgoing file transfers and
+// sends an ipn.Notify with the full merged list. The updates map is keyed by
+// OutgoingFile.ID; existing entries not present in updates are preserved.
+func (e *Extension) UpdateOutgoingFiles(updates map[string]*ipn.OutgoingFile) {
+	e.updateOutgoingFiles(updates)
+}
+
 // updateOutgoingFiles updates b.outgoingFiles to reflect the given updates and
 // sends an ipn.Notify with the full list of outgoingFiles.
 func (e *Extension) updateOutgoingFiles(updates map[string]*ipn.OutgoingFile) {

feature/taildrop/send.go

@@ -134,8 +134,9 @@ func (m *manager) PutFile(id clientID, baseName string, r io.Reader, offset, len
 		}
 	}
 
-	// Copy the contents of the file to the writer.
-	copyLength, err := io.Copy(wc, r)
+	// Copy via inFile (which wraps wc) so [incomingFile.Write] can track
+	// progress and fire periodic sendFileNotify callbacks.
+	copyLength, err := io.Copy(inFile, r)
 	if err != nil {
 		return 0, m.redactAndLogError("Copy", err)
 	}