- add: session-service

- move: redis_cache from database service to utils so it can be reused
- update: redis_cache set function to allow creating a key without a lifetime
- update: services to use the new get_or_generate_service_id function

proto/session_service_api.proto

@@ -0,0 +1,36 @@
+syntax = "proto3";
+
+package session_service_api;
+
+service SessionService {
+  rpc CreateSession (CreateSessionRequest) returns (SessionResponse);
+  rpc GetSession (GetSessionRequest) returns (SessionResponse);
+  rpc DeleteSession (DeleteSessionRequest) returns (Empty);
+}
+
+message CreateSessionRequest {
+  string session_id = 1;
+  int32 user_id = 2;
+  string username = 3;
+  int32 character_id = 4;
+  string ip_address = 5;
+}
+
+message GetSessionRequest {
+  string session_id = 1;
+}
+
+message DeleteSessionRequest {
+  string session_id = 1;
+}
+
+message SessionResponse {
+  string session_id = 1;
+  int32 user_id = 2;
+  string username = 3;
+  int32 character_id = 4;
+  string login_time = 5;
+  string ip_address = 6;
+}
+
+message Empty {}