[Streaming] Streaming data transfer and python integration (#6185)

streaming/src/queue/utils.h

@@ -0,0 +1,50 @@
+#ifndef _STREAMING_QUEUE_UTILS_H_
+#define _STREAMING_QUEUE_UTILS_H_
+#include <chrono>
+#include <future>
+#include <thread>
+#include "ray/util/util.h"
+
+namespace ray {
+namespace streaming {
+
+/// Helper class encapulate std::future to help multithread async wait.
+class PromiseWrapper {
+ public:
+  Status Wait() {
+    std::future<bool> fut = promise_.get_future();
+    fut.get();
+    return status_;
+  }
+
+  Status WaitFor(uint64_t timeout_ms) {
+    std::future<bool> fut = promise_.get_future();
+    std::future_status status;
+    do {
+      status = fut.wait_for(std::chrono::milliseconds(timeout_ms));
+      if (status == std::future_status::deferred) {
+      } else if (status == std::future_status::timeout) {
+        return Status::Invalid("timeout");
+      } else if (status == std::future_status::ready) {
+        return status_;
+      }
+    } while (status == std::future_status::deferred);
+
+    return status_;
+  }
+
+  void Notify(Status status) {
+    status_ = status;
+    promise_.set_value(true);
+  }
+
+  Status GetResultStatus() { return status_; }
+
+ private:
+  std::promise<bool> promise_;
+  Status status_;
+};
+
+}  // namespace streaming
+}  // namespace ray
+#endif