Files
marathon/crates/libmarathon/src/networking/join_protocol.rs
Sienna Meridian Satterwhite 99e31b1157 removed bincode for rkyv
Signed-off-by: Sienna Meridian Satterwhite <sienna@r3t.io>
2025-12-17 19:20:34 +00:00

547 lines
18 KiB
Rust

//! Join protocol for new peer onboarding
//!
//! This module handles the protocol for new peers to join an existing session
//! and receive the full world state. The join flow:
//!
//! 1. New peer sends JoinRequest with node ID and optional session secret
//! 2. Existing peer validates request and responds with FullState
//! 3. New peer applies FullState to initialize local world
//! 4. New peer begins participating in delta synchronization
//!
//! **NOTE:** This is a simplified implementation for Phase 7. Full security
//! and session management will be enhanced in Phase 13.
use bevy::prelude::*;
use crate::networking::{
GossipBridge,
NetworkedEntity,
SessionId,
VectorClock,
blob_support::BlobStore,
delta_generation::NodeVectorClock,
entity_map::NetworkEntityMap,
messages::{
EntityState,
JoinType,
SyncMessage,
VersionedMessage,
},
};
/// Build a JoinRequest message
///
/// # Arguments
/// * `node_id` - The UUID of the node requesting to join
/// * `session_id` - The session to join
/// * `session_secret` - Optional pre-shared secret for authentication
/// * `last_known_clock` - Optional vector clock from previous session (for rejoin)
/// * `join_type` - Whether this is a fresh join or rejoin
///
/// # Example
///
/// ```
/// use libmarathon::networking::{build_join_request, SessionId, JoinType};
/// use uuid::Uuid;
///
/// let node_id = Uuid::new_v4();
/// let session_id = SessionId::new();
/// let request = build_join_request(node_id, session_id, None, None, JoinType::Fresh);
/// ```
pub fn build_join_request(
node_id: uuid::Uuid,
session_id: SessionId,
session_secret: Option<Vec<u8>>,
last_known_clock: Option<VectorClock>,
join_type: JoinType,
) -> VersionedMessage {
VersionedMessage::new(SyncMessage::JoinRequest {
node_id,
session_id,
session_secret,
last_known_clock,
join_type,
})
}
/// Build a FullState message containing all networked entities
///
/// This serializes the entire world state for a new peer. Large worlds may
/// take significant bandwidth - Phase 14 will add compression.
///
/// # Parameters
///
/// - `world`: Bevy world containing entities
/// - `query`: Query for all NetworkedEntity components
/// - `type_registry`: Component type registry for serialization
/// - `node_clock`: Current node vector clock
/// - `blob_store`: Optional blob store for large components
///
/// # Returns
///
/// A FullState message ready to send to the joining peer
pub fn build_full_state(
world: &World,
networked_entities: &Query<(Entity, &NetworkedEntity)>,
type_registry: &crate::persistence::ComponentTypeRegistry,
node_clock: &NodeVectorClock,
blob_store: Option<&BlobStore>,
) -> VersionedMessage {
use crate::{
networking::{
blob_support::create_component_data,
messages::ComponentState,
},
};
let mut entities = Vec::new();
for (entity, networked) in networked_entities.iter() {
let mut components = Vec::new();
// Serialize all registered Synced components on this entity
let serialized_components = type_registry.serialize_entity_components(world, entity);
for (discriminant, _type_path, serialized) in serialized_components {
// Create component data (inline or blob)
let data = if let Some(store) = blob_store {
match create_component_data(serialized, store) {
| Ok(d) => d,
| Err(_) => continue,
}
} else {
crate::networking::ComponentData::Inline(serialized)
};
components.push(ComponentState {
discriminant,
data,
});
}
entities.push(EntityState {
entity_id: networked.network_id,
owner_node_id: networked.owner_node_id,
vector_clock: node_clock.clock.clone(),
components,
is_deleted: false,
});
}
info!(
"Built FullState with {} entities for new peer",
entities.len()
);
VersionedMessage::new(SyncMessage::FullState {
entities,
vector_clock: node_clock.clock.clone(),
})
}
/// Apply a FullState message to the local world
///
/// This initializes the world for a newly joined peer by spawning all entities
/// and applying their component state.
///
/// # Parameters
///
/// - `entities`: List of entity states from FullState message
/// - `vector_clock`: Vector clock from FullState
/// - `commands`: Bevy commands for spawning entities
/// - `entity_map`: Entity map to populate
/// - `type_registry`: Component type registry for deserialization
/// - `node_clock`: Our node's vector clock to update
/// - `blob_store`: Optional blob store for resolving blob references
/// - `tombstone_registry`: Optional tombstone registry for deletion tracking
pub fn apply_full_state(
entities: Vec<EntityState>,
remote_clock: crate::networking::VectorClock,
world: &mut World,
type_registry: &crate::persistence::ComponentTypeRegistry,
) {
use crate::networking::blob_support::get_component_data;
info!("Applying FullState with {} entities", entities.len());
// Merge the remote vector clock
{
let mut node_clock = world.resource_mut::<NodeVectorClock>();
node_clock.clock.merge(&remote_clock);
}
// Spawn all entities and apply their state
for entity_state in entities {
// Handle deleted entities (tombstones)
if entity_state.is_deleted {
// Record tombstone
if let Some(mut registry) = world.get_resource_mut::<crate::networking::TombstoneRegistry>() {
registry.record_deletion(
entity_state.entity_id,
entity_state.owner_node_id,
entity_state.vector_clock.clone(),
);
}
continue;
}
// Spawn entity with NetworkedEntity and Persisted components
// This ensures entities received via FullState are persisted locally
let entity = world
.spawn((
NetworkedEntity::with_id(entity_state.entity_id, entity_state.owner_node_id),
crate::persistence::Persisted::with_id(entity_state.entity_id),
))
.id();
// Register in entity map
{
let mut entity_map = world.resource_mut::<NetworkEntityMap>();
entity_map.insert(entity_state.entity_id, entity);
}
let num_components = entity_state.components.len();
// Apply all components
for component_state in &entity_state.components {
// Get the actual data (resolve blob if needed)
let data_bytes = match &component_state.data {
| crate::networking::ComponentData::Inline(bytes) => bytes.clone(),
| blob_ref @ crate::networking::ComponentData::BlobRef { .. } => {
let blob_store = world.get_resource::<BlobStore>();
if let Some(store) = blob_store.as_deref() {
match get_component_data(blob_ref, store) {
| Ok(bytes) => bytes,
| Err(e) => {
error!(
"Failed to retrieve blob for discriminant {}: {}",
component_state.discriminant, e
);
continue;
},
}
} else {
error!(
"Blob reference for discriminant {} but no blob store available",
component_state.discriminant
);
continue;
}
},
};
// Use the discriminant directly from ComponentState
let discriminant = component_state.discriminant;
// Deserialize the component
let boxed_component = match type_registry.deserialize(discriminant, &data_bytes) {
| Ok(component) => component,
| Err(e) => {
error!(
"Failed to deserialize discriminant {}: {}",
discriminant, e
);
continue;
},
};
// Get the insert function for this discriminant
let Some(insert_fn) = type_registry.get_insert_fn(discriminant) else {
error!("No insert function for discriminant {}", discriminant);
continue;
};
// Insert the component directly
let type_name_for_log = type_registry.get_type_name(discriminant)
.unwrap_or("unknown");
if let Ok(mut entity_mut) = world.get_entity_mut(entity) {
insert_fn(&mut entity_mut, boxed_component);
debug!("Applied component {} from FullState", type_name_for_log);
}
}
debug!(
"Spawned entity {:?} from FullState with {} components",
entity_state.entity_id, num_components
);
}
info!("FullState applied successfully");
}
/// System to handle JoinRequest messages
///
/// When we receive a JoinRequest, build and send a FullState response.
///
/// Add this to your app:
///
/// ```no_run
/// use bevy::prelude::*;
/// use libmarathon::networking::handle_join_requests_system;
///
/// App::new().add_systems(Update, handle_join_requests_system);
/// ```
pub fn handle_join_requests_system(
world: &World,
bridge: Option<Res<GossipBridge>>,
networked_entities: Query<(Entity, &NetworkedEntity)>,
type_registry: Res<crate::persistence::ComponentTypeRegistryResource>,
node_clock: Res<NodeVectorClock>,
blob_store: Option<Res<BlobStore>>,
) {
let Some(bridge) = bridge else {
return;
};
let registry = type_registry.0;
let blob_store_ref = blob_store.as_deref();
// Poll for incoming JoinRequest messages
while let Some(message) = bridge.try_recv() {
match message.message {
| SyncMessage::JoinRequest {
node_id,
session_id,
session_secret,
last_known_clock: _,
join_type,
} => {
info!(
"Received JoinRequest from node {} for session {} (type: {:?})",
node_id, session_id, join_type
);
// Validate session secret if configured
if let Some(expected) =
world.get_resource::<crate::networking::plugin::SessionSecret>()
{
match &session_secret {
| Some(provided_secret) => {
if let Err(e) = crate::networking::validate_session_secret(
provided_secret,
expected.as_bytes(),
) {
error!("JoinRequest from {} rejected: {}", node_id, e);
continue; // Skip this request, don't send FullState
}
info!("Session secret validated for node {}", node_id);
},
| None => {
warn!(
"JoinRequest from {} missing required session secret, rejecting",
node_id
);
continue; // Reject requests without secret when one is configured
},
}
} else if session_secret.is_some() {
// No session secret configured but peer provided one
debug!("Session secret provided but none configured, accepting");
}
// Build full state
let full_state = build_full_state(
world,
&networked_entities,
&registry,
&node_clock,
blob_store_ref,
);
// Send full state to joining peer
if let Err(e) = bridge.send(full_state) {
error!("Failed to send FullState: {}", e);
} else {
info!("Sent FullState to node {}", node_id);
}
},
| _ => {
// Not a JoinRequest, ignore (other systems handle other
// messages)
},
}
}
}
/// System to handle FullState messages
///
/// When we receive a FullState (after sending JoinRequest), apply it to our
/// world.
///
/// This system should run BEFORE receive_and_apply_deltas_system to ensure
/// we're fully initialized before processing deltas.
pub fn handle_full_state_system(world: &mut World) {
// Check if bridge exists
if world.get_resource::<GossipBridge>().is_none() {
return;
}
let bridge = world.resource::<GossipBridge>().clone();
let type_registry = {
let registry_resource = world.resource::<crate::persistence::ComponentTypeRegistryResource>();
registry_resource.0
};
// Poll for FullState messages
while let Some(message) = bridge.try_recv() {
match message.message {
| SyncMessage::FullState {
entities,
vector_clock,
} => {
info!("Received FullState with {} entities", entities.len());
apply_full_state(
entities,
vector_clock,
world,
type_registry,
);
},
| _ => {
// Not a FullState, ignore
},
}
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::networking::VectorClock;
#[test]
fn test_build_join_request() {
let node_id = uuid::Uuid::new_v4();
let session_id = SessionId::new();
let request = build_join_request(node_id, session_id.clone(), None, None, JoinType::Fresh);
match request.message {
| SyncMessage::JoinRequest {
node_id: req_node_id,
session_id: req_session_id,
session_secret,
last_known_clock,
join_type,
} => {
assert_eq!(req_node_id, node_id);
assert_eq!(req_session_id, session_id);
assert!(session_secret.is_none());
assert!(last_known_clock.is_none());
assert!(matches!(join_type, JoinType::Fresh));
},
| _ => panic!("Expected JoinRequest"),
}
}
#[test]
fn test_build_join_request_with_secret() {
let node_id = uuid::Uuid::new_v4();
let session_id = SessionId::new();
let secret = vec![1, 2, 3, 4];
let request = build_join_request(
node_id,
session_id.clone(),
Some(secret.clone()),
None,
JoinType::Fresh,
);
match request.message {
| SyncMessage::JoinRequest {
node_id: _,
session_id: req_session_id,
session_secret,
last_known_clock,
join_type,
} => {
assert_eq!(req_session_id, session_id);
assert_eq!(session_secret, Some(secret));
assert!(last_known_clock.is_none());
assert!(matches!(join_type, JoinType::Fresh));
},
| _ => panic!("Expected JoinRequest"),
}
}
#[test]
fn test_build_join_request_rejoin() {
let node_id = uuid::Uuid::new_v4();
let session_id = SessionId::new();
let clock = VectorClock::new();
let join_type = JoinType::Rejoin {
last_active: 1234567890,
entity_count: 42,
};
let request = build_join_request(
node_id,
session_id.clone(),
None,
Some(clock.clone()),
join_type.clone(),
);
match request.message {
| SyncMessage::JoinRequest {
node_id: req_node_id,
session_id: req_session_id,
session_secret,
last_known_clock,
join_type: req_join_type,
} => {
assert_eq!(req_node_id, node_id);
assert_eq!(req_session_id, session_id);
assert!(session_secret.is_none());
assert_eq!(last_known_clock, Some(clock));
assert!(matches!(req_join_type, JoinType::Rejoin { .. }));
},
| _ => panic!("Expected JoinRequest"),
}
}
#[test]
fn test_entity_state_structure() {
let entity_id = uuid::Uuid::new_v4();
let owner_node_id = uuid::Uuid::new_v4();
let state = EntityState {
entity_id,
owner_node_id,
vector_clock: VectorClock::new(),
components: vec![],
is_deleted: false,
};
assert_eq!(state.entity_id, entity_id);
assert_eq!(state.owner_node_id, owner_node_id);
assert_eq!(state.components.len(), 0);
assert!(!state.is_deleted);
}
#[test]
fn test_apply_full_state_empty() {
let node_id = uuid::Uuid::new_v4();
let remote_clock = VectorClock::new();
let type_registry = crate::persistence::component_registry();
// Need a minimal Bevy app for testing
let mut app = App::new();
// Insert required resources
app.insert_resource(NetworkEntityMap::new());
app.insert_resource(NodeVectorClock::new(node_id));
apply_full_state(
vec![],
remote_clock.clone(),
app.world_mut(),
type_registry,
);
// Should have merged clocks
let node_clock = app.world().resource::<NodeVectorClock>();
assert_eq!(node_clock.clock, remote_clock);
}
}