raven
d906cd8d64
Added movement updates Updated how entities are checked Events sending between packet service all the way to the logic service
World Service
The World Service manages the game world state and character interactions in the MMORPG server architecture.
Overview
The World Service is responsible for:
- Managing character positions and movement
- Handling map changes
- Processing character interactions
- Managing NPCs, monsters, and objects
- Handling combat and skills
Architecture
The service is built using the following components:
- gRPC Server: Exposes world management endpoints
- World State Manager: Maintains the current state of the game world
- Map Manager: Handles map data and transitions
- Entity Manager: Manages characters, NPCs, and monsters
Service Endpoints
The World Service exposes the following gRPC endpoints:
GetCharacter
Retrieves a character's world state.
rpc GetCharacter(CharacterRequest) returns (CharacterResponse);
ChangeMap
Handles a character changing maps.
rpc ChangeMap(ChangeMapRequest) returns (ChangeMapResponse);
MoveCharacter
Updates a character's position.
rpc MoveCharacter(CharacterMoveRequest) returns (CharacterMoveResponse);
GetTargetHp
Retrieves an object's current HP.
rpc GetTargetHp(ObjectHpRequest) returns (ObjectHpResponse);
World Data Structure
The world consists of:
- Maps: Different areas with unique IDs
- Spawn Points: Locations where characters can appear
- NPCs: Non-player characters with fixed positions
- Monsters: Hostile entities that can move and attack
- Objects: Interactive items in the world
Configuration
The service can be configured using environment variables:
LISTEN_ADDR: The address to listen on (default: "0.0.0.0")SERVICE_PORT: The port to listen on (default: "50054")LOG_LEVEL: Logging level (default: "info")MAP_IDS: Comma-separated list of map IDs to manage (e.g., "42,43,44,45")WORLD_SERVICE_NAME: Name of the world service instance (default: "default-service")
Game Logic Connection Retry Configuration
The world service includes comprehensive retry logic for connecting to game logic instances that may not be ready immediately:
Connection Info Retrieval Retry
CONNECTION_INFO_MAX_RETRIES: Maximum number of retry attempts for getting pod connection info (default: 3)CONNECTION_INFO_INITIAL_DELAY_MS: Initial delay between connection info retries in milliseconds (default: 2000)CONNECTION_INFO_MAX_DELAY_MS: Maximum delay between connection info retries in milliseconds (default: 10000)
gRPC Client Connection Retry
GAME_LOGIC_MAX_RETRIES: Maximum number of retry attempts for gRPC connections (default: 5)GAME_LOGIC_INITIAL_DELAY_MS: Initial delay between gRPC connection retries in milliseconds (default: 500)GAME_LOGIC_MAX_DELAY_MS: Maximum delay between gRPC connection retries in milliseconds (default: 10000)
Both retry mechanisms use exponential backoff, doubling the delay after each failed attempt up to the maximum delay. The service will continue starting even if some game logic instances fail to connect, allowing for partial functionality.
Kubernetes Service Creation
The world service automatically creates both Pods and Services for each game logic instance:
- Pod: Contains the game logic service container
- Service: Provides stable networking and service discovery
- Type: ClusterIP
- Port: 50056 (gRPC)
- Selector: Matches specific instance by app, map_id, and instance labels
The world service connects to game logic instances using Kubernetes Service DNS names (e.g., world-default-service-42-service.default.svc.cluster.local) instead of direct Pod IPs, providing better reliability and following Kubernetes best practices.
Running the Service
Local Development
cargo run
Docker
docker build -t world-service .
docker run -p 50054:50054 world-service
Integration with External Systems
The World Service integrates with:
- Database Service: For retrieving and storing world state
- Auth Service: For user authentication and authorization
- Character Service: For character data
- Packet Service: For handling client requests related to the world