update interface based on comment v1

Signed-off-by: Miles Song <[email protected]>

Author: boda26

vmsdk/src/cluster_map.h

@@ -10,12 +10,45 @@
 
 #include <bitset>
 #include <string>
+#include <string_view>
 #include <vector>
 
 #include "src/query/fanout_template.h"
 #include "src/valkeymodule.h"
 
 namespace vmsdk {
+namespace cluster_map {
+
+const size_t NUM_SLOTS = 16384;
+
+// Enumeration for fanout target modes
+enum class FanoutTargetMode {
+  kRandom,        // Default: randomly select one node per shard
+  kReplicasOnly,  // Select only replicas, one per shard
+  kPrimary,       // Select all primary (master) nodes
+  kAll            // Select all nodes (both primary and replica)
+};
+
+struct NodeInfo {
+  enum Type {
+    kLocal,
+    kRemote,
+  };
+  std::string node_id;
+  Type type;
+  // Empty string if type is kLocal.
+  std::string address;
+
+  bool operator==(const NodeInfo& other) const {
+    return type == other.type && address == other.address;
+  }
+
+  friend std::ostream& operator<<(std::ostream& os, const NodeInfo& target) {
+    os << "NodeInfo{type: " << target.type << ", address: " << target.address
+       << "}";
+    return os;
+  }
+};
 
 struct ShardInfo {
   // shard_id is the primary node id
@@ -28,46 +61,52 @@ struct ShardInfo {
 };
 
 class ClusterMap {
-  // flexible to add other getter methods
  public:
+  const std::vector<NodeInfo>& GetPrimaryTargets() const;
+  const std::vector<NodeInfo>& GetReplicaTargets() const;
+  const std::vector<NodeInfo>& GetRandomTargets() const;
+  const std::vector<NodeInfo>& GetAllTargets() const;
+
   // create a new cluster map in the background
   static std::shared_ptr<ClusterMap> CreateNewClusterMap(ValkeyModuleCtx* ctx);
 
   // slot ownership checks
   bool IsSlotOwned(uint16_t slot) const;
 
   // shard lookups
-  const ShardInfo* GetShardById(const std::string& shard_id) const;
-  const std::string& GetShardIdBySlot(uint16_t slot) const;
+  const ShardInfo* GetShardById(std::string_view shard_id) const;
   const absl::flat_hash_map<std::string, ShardInfo>& GetAllShards() const;
 
   // get cluster level slot fingerprint
   uint64_t GetClusterSlotsFingerprint() const;
 
   // get fingerprint for a specific shard
-  uint64_t GetShardSlotsFingerprint(const std::string& shard_id) const;
+  uint64_t GetShardSlotsFingerprint(std::string_view shard_id) const;
 
  private:
   // 1: slot is owned by this cluster, 0: slot is not owned by this cluster
-  std::bitset<16384> owned_slots_;
+  std::bitset<NUM_SLOTS> owned_slots_;
 
   // slot-to-shard lookup
-  std::array<std::string, 16384> slot_to_shard_id_;
+  std::array<std::string, NUM_SLOTS> slot_to_shard_id_;
 
   absl::flat_hash_map<std::string, ShardInfo> shards_;
 
   // Cluster-level fingerprint (hash of all shard fingerprints)
   uint64_t cluster_slots_fingerprint_;
 
   // Pre-computed target lists
-  std::vector<valkey_search::query::fanout::FanoutSearchTarget>
-      primary_targets_;
-  std::vector<valkey_search::query::fanout::FanoutSearchTarget>
-      replica_targets_;
-  std::vector<valkey_search::query::fanout::FanoutSearchTarget> random_targets_;
-  std::vector<valkey_search::query::fanout::FanoutSearchTarget> all_targets_;
+  std::vector<NodeInfo> primary_targets_;
+  std::vector<NodeInfo> replica_targets_;
+  std::vector<NodeInfo> random_targets_;
+  std::vector<NodeInfo> all_targets_;
+
+  // private helper function to refresh targets in CreateNewClusterMap
+  std::vector<NodeInfo> GetTargets(ValkeyModuleCtx* ctx,
+                                   FanoutTargetMode target_mode);
 };
 
+}  // namespace cluster_map
 }  // namespace vmsdk
 
 #endif  // VMSDK_SRC_CLUSTER_MAP_H_