Complete refactor to new grpc control plane and only http proxy for carts (#4)

Co-authored-by: matst80 <mats.tornberg@gmail.com>
Reviewed-on: https://git.tornberg.me/mats/go-cart-actor/pulls/4
Co-authored-by: Mats Törnberg <mats@tornberg.me>
Co-committed-by: Mats Törnberg <mats@tornberg.me>

proto/control_plane.proto

@@ -0,0 +1,101 @@
+syntax = "proto3";
+
+package messages;
+
+option go_package = "git.tornberg.me/go-cart-actor/proto;messages";
+
+// -----------------------------------------------------------------------------
+// Control Plane gRPC API
+// -----------------------------------------------------------------------------
+// Replaces the legacy custom frame-based control channel (previously port 1338).
+// Responsibilities:
+//   - Liveness (Ping)
+//   - Membership negotiation (Negotiate)
+//   - Deterministic ring-based ownership (ConfirmOwner RPC removed)
+//   - Actor ID listing for remote grain spawning (GetActorIds)
+//   - Graceful shutdown notifications (Closing)
+// No authentication / TLS is defined initially (can be added later).
+// -----------------------------------------------------------------------------
+
+// Empty request placeholder (common pattern).
+message Empty {}
+
+// Ping reply includes responding host and its current unix time (seconds).
+message PingReply {
+  string host = 1;
+  int64 unix_time = 2;
+}
+
+// NegotiateRequest carries the caller's full view of known hosts (including self).
+message NegotiateRequest {
+  repeated string known_hosts = 1;
+}
+
+// NegotiateReply returns the callee's healthy hosts (including itself).
+message NegotiateReply {
+  repeated string hosts = 1;
+}
+
+// CartIdsReply returns the list of cart IDs (string form) currently owned locally.
+message ActorIdsReply {
+  repeated uint64 ids = 1;
+}
+
+// OwnerChangeAck retained as response type for Closing RPC (ConfirmOwner removed).
+message OwnerChangeAck {
+  bool accepted = 1;
+  string message = 2;
+}
+
+// ClosingNotice notifies peers this host is terminating (so they can drop / re-resolve).
+message ClosingNotice {
+  string host = 1;
+}
+
+// OwnershipAnnounce broadcasts first-touch ownership claims for cart IDs.
+// First claim wins; receivers SHOULD NOT overwrite an existing different owner.
+message OwnershipAnnounce {
+  string host = 1;               // announcing host
+  repeated uint64 ids = 2;   // newly claimed cart ids
+}
+
+// ExpiryAnnounce broadcasts that a host evicted the provided cart IDs.
+message ExpiryAnnounce {
+  string host = 1;
+  repeated uint64 ids = 2;
+}
+
+// ControlPlane defines cluster coordination and ownership operations.
+service ControlPlane {
+  // Ping for liveness; lightweight health signal.
+  rpc Ping(Empty) returns (PingReply);
+
+  // Negotiate merges host views; used during discovery & convergence.
+  rpc Negotiate(NegotiateRequest) returns (NegotiateReply);
+
+  // GetCartIds lists currently owned cart IDs on this node.
+  rpc GetLocalActorIds(Empty) returns (ActorIdsReply);
+
+  // ConfirmOwner RPC removed (was legacy ownership acknowledgement; ring-based ownership now authoritative)
+
+  // Ownership announcement: first-touch claim broadcast (idempotent; best-effort).
+  rpc AnnounceOwnership(OwnershipAnnounce) returns (OwnerChangeAck);
+
+  // Expiry announcement: drop remote ownership hints when local TTL expires.
+  rpc AnnounceExpiry(ExpiryAnnounce) returns (OwnerChangeAck);
+
+  // Closing announces graceful shutdown so peers can proactively adjust.
+  rpc Closing(ClosingNotice) returns (OwnerChangeAck);
+}
+
+// -----------------------------------------------------------------------------
+// Generation Instructions:
+// protoc --go_out=. --go_opt=paths=source_relative \
+//        --go-grpc_out=. --go-grpc_opt=paths=source_relative \
+//        control_plane.proto
+//
+// Future Enhancements:
+//  - Add a streaming membership watch (server -> client) for immediate updates.
+//  - Add TLS / mTLS for secure intra-cluster communication.
+//  - Add richer health metadata (load, grain count) in PingReply.
+// -----------------------------------------------------------------------------

proto/messages.proto

@@ -1,83 +1,77 @@
 syntax = "proto3";
 package messages;
-option go_package = ".;messages";
+option go_package = "git.tornberg.me/go-cart-actor/proto;messages";
 
-message AddRequest {
-		int32 quantity = 1;
-		string sku = 2;
-		string country = 3;
-		optional string storeId = 4;
-}
+message ClearCartRequest {
 
-message SetCartRequest {
-		repeated AddRequest items = 1;
 }
 
 message AddItem {
-		int64 item_id = 1;
-		int32 quantity = 2;
-		int64 price = 3;
-		int64 orgPrice = 9;
-		string sku = 4;
-		string name = 5;
-		string image = 6;
-		int32 stock = 7;
-		int32 tax = 8;
-		string brand = 13;
-		string category = 14;
-		string category2 = 15;
-		string category3 = 16;
-		string category4 = 17;
-		string category5 = 18;
-		string disclaimer = 10;
-		string articleType = 11;
-		string sellerId = 19;
-		string sellerName = 20;
-		string country = 21;
-		optional string outlet = 12;
-		optional string storeId = 22;
+	uint32 item_id = 1;
+	int32 quantity = 2;
+	int64 price = 3;
+	int64 orgPrice = 9;
+	string sku = 4;
+	string name = 5;
+	string image = 6;
+	int32 stock = 7;
+	int32 tax = 8;
+	string brand = 13;
+	string category = 14;
+	string category2 = 15;
+	string category3 = 16;
+	string category4 = 17;
+	string category5 = 18;
+	string disclaimer = 10;
+	string articleType = 11;
+	string sellerId = 19;
+	string sellerName = 20;
+	string country = 21;
+	optional string outlet = 12;
+	optional string storeId = 22;
+	optional uint32 parentId = 23;
 }
 
 message RemoveItem {
-		int64 Id = 1;
+	uint32 Id = 1;
 }
 
 message ChangeQuantity {
-		int64 id = 1;
-		int32 quantity = 2;
+    uint32 Id = 1;
+	int32 quantity = 2;
 }
 
 message SetDelivery {
-		string provider = 1;
-		repeated int64 items = 2;
-		optional PickupPoint pickupPoint = 3;
-		string country = 4;
-		string zip = 5;
-		optional string address = 6;
-		optional string city = 7;
+	string provider = 1;
+	repeated uint32 items = 2;
+	optional PickupPoint pickupPoint = 3;
+	string country = 4;
+	string zip = 5;
+	optional string address = 6;
+	optional string city = 7;
 }
 
 message SetPickupPoint {
-        int64 deliveryId = 1;
-        string id = 2;
-        optional string name = 3;
-        optional string address = 4;
-        optional string city = 5;
-        optional string zip = 6;
-        optional string country = 7;
+	uint32 deliveryId = 1;
+	string id = 2;
+	optional string name = 3;
+	optional string address = 4;
+	optional string city = 5;
+	optional string zip = 6;
+	optional string country = 7;
 }
 
 message PickupPoint {
-        string id = 1;
-        optional string name = 2;
-        optional string address = 3;
-        optional string city = 4;
-        optional string zip = 5;
-        optional string country = 6;
+	string id = 1;
+	optional string name = 2;
+	optional string address = 3;
+	optional string city = 4;
+	optional string zip = 5;
+	optional string country = 6;
 }
 
 message RemoveDelivery {
-		int64 id = 1;
+	uint32 id = 1;
 }
 
 message CreateCheckoutOrder {
@@ -90,6 +84,33 @@ message CreateCheckoutOrder {
 }
 
 message OrderCreated {
-		string orderId = 1;
-		string status = 2;
+	string orderId = 1;
+	string status = 2;
+}
+
+message Noop {
+	// Intentionally empty - used for ownership acquisition or health pings
+}
+
+message InitializeCheckout {
+	string orderId = 1;
+	string status = 2;
+	bool paymentInProgress = 3;
+}
+
+message VoucherRule {
+	string type = 2;
+	string description = 3;
+	string condition = 4;
+	string action = 5;
+}
+
+message AddVoucher {
+    string code = 1;
+    int64 value = 2;
+    repeated VoucherRule voucherRules = 3;
+}
+
+message RemoveVoucher {
+    uint32 id = 1;
 }