Move execution storage to new package

pkg/execution/local_storage.go

@@ -0,0 +1,35 @@
+package execution
+
+import (
+	"gitlab.hpi.de/codeocean/codemoon/poseidon/pkg/dto"
+	"sync"
+)
+
+// localStorage stores execution objects in the local application memory.
+// ToDo: Create implementation that use some persistent storage like a database.
+type localStorage struct {
+	sync.RWMutex
+	executions map[ID]*dto.ExecutionRequest
+}
+
+// NewLocalStorage responds with an Storage implementation.
+// This implementation stores the data thread-safe in the local application memory.
+func NewLocalStorage() *localStorage {
+	return &localStorage{
+		executions: make(map[ID]*dto.ExecutionRequest),
+	}
+}
+
+func (s *localStorage) Add(id ID, executionRequest *dto.ExecutionRequest) {
+	s.Lock()
+	defer s.Unlock()
+	s.executions[id] = executionRequest
+}
+
+func (s *localStorage) Pop(id ID) (*dto.ExecutionRequest, bool) {
+	s.Lock()
+	defer s.Unlock()
+	request, ok := s.executions[id]
+	delete(s.executions, id)
+	return request, ok
+}