feat: files up to 512 MB as streams, a code editor with highlighting and find/replace, media preview, hex editing; touch selection in the terminal (0.0.7)

internal/agent/client.go

@@ -48,6 +48,7 @@ type state struct {
 type Agent struct {
 	cfg       Config
 	http      *http.Client
+	stream    *http.Client
 	state     state
 	pollCount int
 
@@ -81,6 +82,8 @@ func New(cfg Config) *Agent {
 		cfg: cfg,
 		// Timeout must exceed the server's long-poll hold (25s) plus slack.
 		http: &http.Client{Timeout: 60 * time.Second, Transport: tr},
+		// File streams take as long as the file needs.
+		stream: &http.Client{Transport: tr},
 	}
 }
 

internal/agent/fsstream.go

@@ -0,0 +1,137 @@
+package agent
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"path/filepath"
+	"strconv"
+	"syscall"
+
+	"github.com/x-grk/longpolling-remote-access/internal/proto"
+)
+
+// File transfers that do not fit a task's JSON: the bytes go as a plain HTTP
+// body through a stream the server holds open for the browser on the other
+// end, so a file is never held whole in memory.
+
+func (a *Agent) streamURL(id string) string { return a.cfg.Host + "/api/agent/fs/stream/" + id }
+
+// doFSUpload writes the file the browser is uploading. It lands in a temporary
+// file next to the target first, so a broken upload leaves the old file as it
+// was.
+func (a *Agent) doFSUpload(ctx context.Context, env proto.TaskEnvelope) proto.TaskResult {
+	var args proto.FSStreamArgs
+	if err := json.Unmarshal(env.Args, &args); err != nil {
+		return proto.TaskResult{Error: err.Error()}
+	}
+	if args.Size > proto.FSFileCap {
+		return proto.TaskResult{Error: "файл больше 512 МБ"}
+	}
+	dir, base := filepath.Split(args.Path)
+	if dir == "" {
+		dir = "."
+	}
+	tmp, err := os.CreateTemp(dir, "."+base+".lpra-*")
+	if err != nil {
+		return proto.TaskResult{Error: err.Error()}
+	}
+	done := false
+	defer func() {
+		if !done {
+			tmp.Close()
+			os.Remove(tmp.Name())
+		}
+	}()
+
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, a.streamURL(args.Stream), nil)
+	if err != nil {
+		return proto.TaskResult{Error: err.Error()}
+	}
+	a.authHeaders(req)
+	resp, err := a.stream.Do(req)
+	if err != nil {
+		return proto.TaskResult{Error: err.Error()}
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		return proto.TaskResult{Error: errStatus(resp.StatusCode).Error()}
+	}
+	n, err := io.Copy(tmp, io.LimitReader(resp.Body, proto.FSFileCap+1))
+	if err != nil {
+		return proto.TaskResult{Error: "загрузка прервана: " + err.Error()}
+	}
+	if n > proto.FSFileCap {
+		return proto.TaskResult{Error: "файл больше 512 МБ"}
+	}
+	if args.Size >= 0 && n != args.Size {
+		return proto.TaskResult{Error: fmt.Sprintf("загрузка прервана: пришло %d из %d байт", n, args.Size)}
+	}
+	if err := tmp.Close(); err != nil {
+		return proto.TaskResult{Error: err.Error()}
+	}
+	// A file that is being replaced keeps its mode and owner.
+	mode := os.FileMode(0o644)
+	if info, err := os.Stat(args.Path); err == nil {
+		if info.IsDir() {
+			return proto.TaskResult{Error: "это каталог"}
+		}
+		mode = info.Mode().Perm()
+		if st, ok := info.Sys().(*syscall.Stat_t); ok {
+			_ = os.Chown(tmp.Name(), int(st.Uid), int(st.Gid))
+		}
+	}
+	if err := os.Chmod(tmp.Name(), mode); err != nil {
+		return proto.TaskResult{Error: err.Error()}
+	}
+	if err := os.Rename(tmp.Name(), args.Path); err != nil {
+		return proto.TaskResult{Error: err.Error()}
+	}
+	done = true
+	data, _ := json.Marshal(map[string]any{"path": args.Path, "size": n})
+	return proto.TaskResult{OK: true, Data: data}
+}
+
+// doFSGet sends a file to the browser that asked for it.
+func (a *Agent) doFSGet(ctx context.Context, env proto.TaskEnvelope) proto.TaskResult {
+	var args proto.FSStreamArgs
+	if err := json.Unmarshal(env.Args, &args); err != nil {
+		return proto.TaskResult{Error: err.Error()}
+	}
+	f, err := os.Open(args.Path)
+	if err != nil {
+		return proto.TaskResult{Error: err.Error()}
+	}
+	defer f.Close()
+	info, err := f.Stat()
+	if err != nil {
+		return proto.TaskResult{Error: err.Error()}
+	}
+	if info.IsDir() {
+		return proto.TaskResult{Error: "это каталог"}
+	}
+	if info.Size() > proto.FSFileCap {
+		return proto.TaskResult{Error: "файл больше 512 МБ"}
+	}
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, a.streamURL(args.Stream), io.LimitReader(f, info.Size()))
+	if err != nil {
+		return proto.TaskResult{Error: err.Error()}
+	}
+	req.ContentLength = info.Size()
+	req.Header.Set("X-Size", strconv.FormatInt(info.Size(), 10))
+	a.authHeaders(req)
+	resp, err := a.stream.Do(req)
+	if err != nil {
+		return proto.TaskResult{Error: err.Error()}
+	}
+	io.Copy(io.Discard, resp.Body)
+	resp.Body.Close()
+	if resp.StatusCode != http.StatusNoContent {
+		return proto.TaskResult{Error: "браузер не дочитал файл"}
+	}
+	data, _ := json.Marshal(map[string]any{"path": args.Path, "size": info.Size()})
+	return proto.TaskResult{OK: true, Data: data}
+}

internal/agent/task.go

@@ -22,6 +22,10 @@ func (a *Agent) runTask(ctx context.Context, taskID string) {
 		res = a.doUpdate()
 	case proto.TaskSysSpeed:
 		res = a.doSpeed(ctx, env)
+	case proto.TaskFSUpload:
+		res = a.doFSUpload(ctx, env)
+	case proto.TaskFSGet:
+		res = a.doFSGet(ctx, env)
 	default:
 		res = a.execTask(env)
 	}