Files
CodeNomad/packages/server/src/clients/connection-manager.ts

129 lines
4.0 KiB
TypeScript

import type { Logger } from "../logger"
const STALE_CONNECTION_TIMEOUT_MS = 45000
const STALE_SWEEP_INTERVAL_MS = 5000
export interface ClientConnectionRef {
clientId: string
connectionId: string
}
export interface ClientConnectionRecord extends ClientConnectionRef {
key: string
connectedAt: number
lastSeenAt: number
}
type ConnectionChangeEvent = {
type: "connected" | "disconnected"
connection: ClientConnectionRecord
reason?: string
}
interface RegisteredConnection extends ClientConnectionRecord {
close: () => void
}
export class ClientConnectionManager {
private readonly connections = new Map<string, RegisteredConnection>()
private readonly subscribers = new Set<(event: ConnectionChangeEvent) => void>()
private readonly sweepTimer: NodeJS.Timeout
constructor(private readonly logger: Logger) {
this.sweepTimer = setInterval(() => this.sweepStaleConnections(), STALE_SWEEP_INTERVAL_MS)
this.sweepTimer.unref?.()
}
shutdown(): void {
clearInterval(this.sweepTimer)
for (const connection of Array.from(this.connections.values())) {
this.disconnect(connection.key, "shutdown", false)
}
}
subscribe(listener: (event: ConnectionChangeEvent) => void): () => void {
this.subscribers.add(listener)
return () => this.subscribers.delete(listener)
}
register(input: ClientConnectionRef & { close: () => void }): () => void {
const key = getConnectionKey(input)
const now = Date.now()
const existing = this.connections.get(key)
if (existing) {
this.logger.debug({ clientId: input.clientId, connectionId: input.connectionId }, "Replacing existing client connection")
this.disconnect(key, "replaced")
}
const connection: RegisteredConnection = {
key,
clientId: input.clientId,
connectionId: input.connectionId,
connectedAt: now,
lastSeenAt: now,
close: input.close,
}
this.connections.set(key, connection)
this.logger.debug({ clientId: input.clientId, connectionId: input.connectionId }, "Client connected")
this.notify({ type: "connected", connection })
return () => this.disconnect(key, "closed")
}
pong(input: ClientConnectionRef): boolean {
const key = getConnectionKey(input)
const connection = this.connections.get(key)
if (!connection) {
this.logger.debug({ clientId: input.clientId, connectionId: input.connectionId }, "Ignoring pong for unknown client connection")
return false
}
connection.lastSeenAt = Date.now()
return true
}
isConnected(input: ClientConnectionRef): boolean {
return this.connections.has(getConnectionKey(input))
}
private sweepStaleConnections(): void {
const cutoff = Date.now() - STALE_CONNECTION_TIMEOUT_MS
for (const connection of Array.from(this.connections.values())) {
if (connection.lastSeenAt > cutoff) continue
this.logger.debug({ clientId: connection.clientId, connectionId: connection.connectionId }, "Client connection timed out")
this.disconnect(connection.key, "timeout")
}
}
private disconnect(key: string, reason: string, invokeClose = true): void {
const connection = this.connections.get(key)
if (!connection) return
this.connections.delete(key)
this.logger.debug({ clientId: connection.clientId, connectionId: connection.connectionId, reason }, "Client disconnected")
if (invokeClose) {
try {
connection.close()
} catch (error) {
this.logger.warn({ err: error, clientId: connection.clientId, connectionId: connection.connectionId }, "Failed to close stale client connection")
}
}
this.notify({ type: "disconnected", connection, reason })
}
private notify(event: ConnectionChangeEvent): void {
for (const subscriber of this.subscribers) {
try {
subscriber(event)
} catch (error) {
this.logger.warn({ err: error, eventType: event.type }, "Client connection subscriber failed")
}
}
}
}
function getConnectionKey(input: ClientConnectionRef): string {
return `${input.clientId}:${input.connectionId}`
}