feat: implement memory state backend with key group assignment and value state interface

1 files changed, 41 insertions, 0 deletions

diff --git a/state/memory_backend.go b/state/memory_backend.go
new file mode 100644
index 0000000..58e86e0
--- /dev/null
+++ b/state/memory_backend.go
@@ -0,0 +1,41 @@
+package state
+
+import (
+	"context"
+	"goflink/core"
+)
+
+// TODO: currently using Golang Map for go through the DAG pipline
+// This should be use index map index map[uint64]uint32  Hash(KeyGroup + StateName + Key) -> Offset
+// with 1GB of []byte allocation
+// This should be optimize with ZERO GC Scanning, Memory Alignment
+
+type MemoryStateBackend struct {
+	maxParallelism  int
+	currentKey      string
+	currentGroupKey int
+	// 3D structure StateName -> KeyGroup -> Key -> Value
+	states map[string]map[int]map[string]any
+}
+
+func NewMemoryStateBackend(maxParallelism int) *MemoryStateBackend {
+	return &MemoryStateBackend{
+		maxParallelism: maxParallelism,
+		states:         make(map[string]map[int]map[string]any),
+	}
+}
+
+func (ms *MemoryStateBackend) GetCurrentKey() string {
+	return ms.currentKey
+}
+
+func (ms *MemoryStateBackend) SetCurrentKey(key string) error {
+	ms.currentKey = key
+	ms.currentGroupKey = core.AssignToKeyGroup(key, ms.maxParallelism)
+	return nil
+}
+
+func (ms *MemoryStateBackend) GetValueState(ctx context.Context, key string) (core.ValueState[any], error) {
+	//TODO implement me
+	panic("implement me")
+}