bet-mcp

/** * This is a copy of the InMemoryEventStore from the typescript-sdk * https://github.com/modelcontextprotocol/typescript-sdk/blob/main/src/examples/shared/inMemoryEventStore.ts */ import type { EventStore } from "@modelcontextprotocol/sdk/server/streamableHttp.js"; import type { JSONRPCMessage } from "@modelcontextprotocol/sdk/types.js"; /** * Simple in-memory implementation of the EventStore interface for resumability * This is primarily intended for examples and testing, not for production use * where a persistent storage solution would be more appropriate. */ export class InMemoryEventStore implements EventStore { private events: Map<string, { message: JSONRPCMessage; streamId: string }> = new Map(); private lastTimestamp = 0; private lastTimestampCounter = 0; /** * Replays events that occurred after a specific event ID * Implements EventStore.replayEventsAfter */ async replayEventsAfter( lastEventId: string, { send, }: { send: (eventId: string, message: JSONRPCMessage) => Promise<void> }, ): Promise<string> { if (!lastEventId || !this.events.has(lastEventId)) { return ""; } // Extract the stream ID from the event ID const streamId = this.getStreamIdFromEventId(lastEventId); if (!streamId) { return ""; } let foundLastEvent = false; // Sort events by eventId for chronological ordering const sortedEvents = [...this.events.entries()].sort((a, b) => a[0].localeCompare(b[0]), ); for (const [ eventId, { message, streamId: eventStreamId }, ] of sortedEvents) { // Only include events from the same stream if (eventStreamId !== streamId) { continue; } // Start sending events after we find the lastEventId if (eventId === lastEventId) { foundLastEvent = true; continue; } if (foundLastEvent) { await send(eventId, message); } } return streamId; } /** * Stores an event with a generated event ID * Implements EventStore.storeEvent */ async storeEvent(streamId: string, message: JSONRPCMessage): Promise<string> { const eventId = this.generateEventId(streamId); this.events.set(eventId, { message, streamId }); return eventId; } /** * Generates a monotonic unique event ID in * `${streamId}_${timestamp}_${counter}_${random}` format. */ private generateEventId(streamId: string): string { const now = Date.now(); if (now === this.lastTimestamp) { this.lastTimestampCounter++; } else { this.lastTimestampCounter = 0; this.lastTimestamp = now; } const timestamp = now.toString(); const counter = this.lastTimestampCounter.toString(36).padStart(4, "0"); const random = Math.random().toString(36).substring(2, 5); return `${streamId}_${timestamp}_${counter}_${random}`; } /** * Extracts the stream ID from an event ID */ private getStreamIdFromEventId(eventId: string): string { const parts = eventId.split("_"); return parts.length > 0 ? parts[0] : ""; } }