Struct GrpcTaskStore 

pub struct GrpcTaskStore { /* private fields */ }

Shared state backing both JSON-RPC and gRPC transports.

Stores task records, push-notification configuration, agent metadata, and task-update fan-out channels for the gRPC service layer. The store is safe to share across concurrent request handlers: task and push-configuration maps use lock-free concurrent access through DashMap, while task updates are distributed with a Tokio broadcast channel.

Responsibilities

• Keep the authoritative in-process local::Task records by task ID.
• Track per-task local::TaskPushNotificationConfig entries used by push-notification subscribers.
• Expose the local local::AgentCard advertised by this server.
• Optionally publish task lifecycle events through AgentBus.
• Broadcast task status changes to active streaming subscribers.

Invariants

• Keys in tasks and push_configs are task IDs.
• Values sent through update_tx use the same task ID namespace as tasks.
• card describes the agent instance served by this store.

Implementations

impl GrpcTaskStore

pub fn new(card: AgentCard) -> Arc<Self>

Create a new task store with the given agent card.

Initializes an empty, shareable GrpcTaskStore for a single local agent. The returned Arc is intended to be cloned into gRPC handlers, JSON-RPC adapters, streaming tasks, and other transport glue that needs access to the same in-process task state.

Parameters

• card - Agent metadata served by this store and returned to clients that request the local agent card.

Returns

A reference-counted store with no tasks, no push-notification configuration, no attached AgentBus, and a task-update broadcast channel sized for 256 queued status updates per receiver.

Side effects

Allocates the concurrent maps and creates a Tokio broadcast channel. It does not publish network services, spawn background tasks, or emit any task updates.

pub fn with_bus(card: AgentCard, bus: Arc<AgentBus>) -> Arc<Self>

Create with an agent bus attached.

Constructs a new store using Self::new and attaches an AgentBus before the store is shared. The bus allows gRPC task activity to be mirrored into the broader agent-event system while preserving the same task storage and update-stream behavior as Self::new.

Parameters

• card - Agent metadata served by this store.
• bus - Shared event bus used to publish or coordinate task activity outside the gRPC transport.

Returns

A reference-counted store with the supplied bus installed.

Panics

Panics only if the freshly created Arc is not uniquely owned before installing the bus. Under normal control flow this cannot happen because the Arc has just been returned by Self::new and has not yet been cloned.

pub fn upsert_task(&self, task: Task)

Insert or update a task.

Stores the provided task by its ID, replacing any existing task with the same ID. Before writing the task into the map, this method broadcasts the task’s current status so live subscribers can react to status changes.

Parameters

• task - Complete task record to insert or replace. Its id field is used as the storage key and as the task ID in the broadcast update.

Side effects

Sends a best-effort status update on the broadcast channel and mutates the in-memory task map. If there are no active receivers, or if receivers have lagged, the broadcast result is ignored; the task is still stored.

pub fn get_task(&self, id: &str) -> Option<Task>

Get a task by id.

Looks up a task in the in-memory store and returns an owned clone so the caller can inspect or serialize it without holding a DashMap guard.

Parameters

• id - Task identifier to retrieve.

Returns

Some(local::Task) when a task with the given ID exists, or None when the store has no matching task.

Side effects

This method does not mutate store state or emit task updates.

pub fn subscribe_updates(&self) -> Receiver<(String, TaskStatus)>

Subscribe to task update notifications.

Creates a new receiver for the live task-status broadcast stream. Each message contains the task ID and the status observed by Self::upsert_task.

Returns

A Tokio broadcast receiver for (task_id, status) tuples. Broadcast receivers are live streams, not durable logs; slow receivers may observe lag errors according to Tokio broadcast-channel semantics.

Side effects

Registers a new receiver with the broadcast channel. It does not read, mutate, or replay existing tasks.

pub fn into_service(self: Arc<Self>) -> A2aServiceServer<A2aServiceImpl>

Build the tonic service layer from this store.

Wraps the shared task store in an A2aServiceImpl and returns the generated tonic A2aServiceServer ready to be mounted into a gRPC server.

Returns

A tonic service server that handles A2A gRPC requests using this store as its backing state.

Side effects

Consumes one Arc handle to the store and moves it into the service implementation. This method does not start listening on a socket; the caller is responsible for adding the returned service to a tonic server.