# rpc 错误：code = Internal desc = grpc: 发送消息失败：流已关闭

- **ID:** `go/grpc-stream-already-closed`
- **领域:** go
- **类别:** runtime_error
- **验证级别:** ai_generated
- **修复率:** 80%

## 根因

在 CloseSend 之后或流返回 io.EOF 之后调用流的 Send。常由多个 goroutine 并发调用 Send 引起。

## 版本兼容性

| 版本 | 状态 | 引入 | 弃用 |
|------|------|------|------|
| 1.50+ | active | — | — |

## 解决方案

1. **** (94% 成功率)
   ```
   for _, m := range msgs {
    if err := stream.Send(m); err != nil {
        if err == io.EOF { break }
        return err
    }
}
return stream.CloseSend()
   ```
2. **** (85% 成功率)
   ```
   for {
    stream, err := client.Push(ctx)
    if err != nil { return err }
    if err := sendAll(stream, batch); err != nil { return err }
    if _, err := stream.CloseAndRecv(); err != nil { return err }
    if done(batch) { return nil }
}
   ```

## 无效尝试

- **** — gRPC streams are one-shot; CloseSend is idempotent but does not reopen the stream for sending. (90% 失败率)
- **** — Subsequent Sends return the same error; the messages are silently dropped. (88% 失败率)