F files

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include/caosdb/filestreaming/Client.h

+#include "caosdb/filestreaming/HandlerInterface.h"
+#include "caosdb/entity/v1alpha1/main.grpc.pb.h"
+#include "caosdb/entity.h"
+#include "caosdb/status_code.h"
+
+#include <grpcpp/grpcpp.h>
+
+#include <iostream>
+#include <memory>
+#include <string>
+
+namespace FileExchange {
+using caosdb::StatusCode;
+using caosdb::entity::FileDescriptor;
+using caosdb::entity::v1alpha1::FileTransmissionService;
+
+class FileExchangeClient final {
+public:
+  FileExchangeClient(
+    const std::shared_ptr<FileTransmissionService::Stub> &service)
+    : stub_(service) {}
+
+  ~FileExchangeClient();
+
+  FileExchangeClient(const FileExchangeClient &) = delete;
+  FileExchangeClient &operator=(const FileExchangeClient &) = delete;
+  FileExchangeClient(FileExchangeClient &&) = delete;
+  FileExchangeClient &operator=(FileExchangeClient &&) = delete;
+
+  StatusCode upload(const FileDescriptor &file_descriptor);
+  StatusCode download(const FileDescriptor &file_descriptor);
+
+  void cancel();
+
+private:
+  int processMessages();
+
+  grpc::CompletionQueue cq_;
+
+  std::shared_ptr<FileTransmissionService::Stub> stub_;
+  std::unique_ptr<HandlerInterface> handler_;
+};
+
+} // namespace FileExchange