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68d7816 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 | import { createActor, type ActorRefFrom } from '#/xstate2';
import type {
Interaction,
InteractionCancellation,
InteractionPendingChangedEvent,
InteractionQuery,
InteractionRequest,
InteractionResolution,
InteractionTags,
} from './interaction';
import { INTERACTION_TAG_AGENT_ID, INTERACTION_TAG_SESSION_ID } from './interaction';
import type { InteractionEmitted, InteractionRecord } from './machine';
import { createInteractionMachine } from './machine';
export type InteractionActor = ActorRefFrom<ReturnType<typeof createInteractionMachine>>;
export type InteractionAgentDispatch = (event: InteractionEmitted) => void;
const RECENTLY_RESOLVED_TTL_MS = 60_000;
const RECENTLY_RESOLVED_MAX = 256;
interface Waiter {
readonly resolve: (response: unknown) => void;
readonly reject: (error: unknown) => void;
readonly timer?: ReturnType<typeof setTimeout>;
}
export interface InteractionFacade {
request<TPayload, TResponse>(req: InteractionRequest<TPayload>): Promise<TResponse>;
enqueue<TPayload>(req: InteractionRequest<TPayload>): Interaction;
respond(id: string, response: unknown): boolean;
findAll(query?: InteractionQuery): readonly Interaction[];
findOne(query: InteractionQuery): Interaction | undefined;
wait<TResponse>(id: string, opts?: { timeoutMs?: number }): Promise<TResponse>;
onDidChangePending(listener: (event: InteractionPendingChangedEvent) => void): () => void;
onDidResolve(listener: (event: InteractionResolution) => void): () => void;
attachAgent(agentId: string, sessionId: string, dispatch: InteractionAgentDispatch): void;
detachAgent(agentId: string, sessionId: string): void;
purgeSession(sessionId: string): void;
stop(): void;
}
function matches(record: InteractionRecord, query: InteractionQuery): boolean {
if (query.id !== undefined && record.id !== query.id) return false;
if (query.kind !== undefined && record.kind !== query.kind) return false;
if (query.resolved !== undefined && record.resolved !== query.resolved) return false;
if (query.tags !== undefined) {
for (const [key, value] of Object.entries(query.tags)) {
if (record.tags[key] !== value) return false;
}
}
return true;
}
export function createInteractionFacade(
actor: InteractionActor,
input?: { now?: () => number },
): InteractionFacade {
const now = input?.now ?? Date.now;
const waiters = new Map<string, Waiter[]>();
const recentlyResolved = new Map<string, number>();
const changeListeners = new Set<(event: InteractionPendingChangedEvent) => void>();
const resolveListeners = new Set<(event: InteractionResolution) => void>();
const agentDispatchers = new Map<string, InteractionAgentDispatch>();
let nextId = 0;
const records = (): Map<string, InteractionRecord> => actor.getSnapshot().context.records;
const pendingIds = (): string[] =>
[...records().values()].filter((record) => !record.resolved).map((record) => record.id);
const firePendingChanged = (): void => {
const event: InteractionPendingChangedEvent = { pending: pendingIds() };
for (const listener of changeListeners) listener(event);
};
const settleWaiters = (id: string, response: unknown): void => {
const entries = waiters.get(id);
if (entries === undefined) return;
waiters.delete(id);
for (const waiter of entries) {
if (waiter.timer !== undefined) clearTimeout(waiter.timer);
waiter.resolve(response);
}
};
const evictResolved = (id: string): void => {
recentlyResolved.delete(id);
actor.send({ type: 'interaction.evict', id });
};
const rememberResolved = (id: string): void => {
const at = now();
for (const [key, resolvedAt] of recentlyResolved) {
if (at - resolvedAt > RECENTLY_RESOLVED_TTL_MS) evictResolved(key);
}
while (recentlyResolved.size >= RECENTLY_RESOLVED_MAX) {
const oldest = recentlyResolved.keys().next().value;
if (oldest === undefined) break;
evictResolved(oldest);
}
recentlyResolved.set(id, at);
};
const dispatchToAgent = (tags: InteractionTags, event: InteractionEmitted): void => {
const agentId = tags[INTERACTION_TAG_AGENT_ID];
const sessionId = tags[INTERACTION_TAG_SESSION_ID];
if (typeof agentId !== 'string' || typeof sessionId !== 'string') return;
agentDispatchers.get(`${sessionId}:${agentId}`)?.(event);
};
const requestedSubscription = actor.on('interaction.requested', (event) => {
dispatchToAgent(event.record.tags, event);
});
const subscription = actor.on('interaction.resolved', (event) => {
settleWaiters(event.id, event.response);
rememberResolved(event.id);
dispatchToAgent(event.record.tags, event);
const resolution: InteractionResolution = { id: event.id, response: event.response };
for (const listener of resolveListeners) listener(resolution);
});
const facade: InteractionFacade = {
request<TPayload, TResponse>(req: InteractionRequest<TPayload>): Promise<TResponse> {
const interaction = facade.enqueue(req);
return facade.wait<TResponse>(interaction.id);
},
enqueue<TPayload>(req: InteractionRequest<TPayload>): Interaction {
const agentId = req.tags?.[INTERACTION_TAG_AGENT_ID];
const id = req.id ?? (agentId === undefined ? `interaction-${nextId++}` : `${String(agentId)}:interaction-${nextId++}`);
const existing = records().get(id);
if (existing !== undefined && !existing.resolved) {
throw new Error(`Interaction "${id}" is already pending`);
}
const interaction: Interaction<TPayload> = {
id,
kind: req.kind,
payload: req.payload,
tags: req.tags ?? {},
createdAt: now(),
};
actor.send({ type: 'interaction.request', record: { ...interaction, resolved: false } });
firePendingChanged();
return interaction;
},
respond(id: string, response: unknown): boolean {
const record = records().get(id);
if (record === undefined || record.resolved) return false;
actor.send({ type: 'interaction.resolve', id, response });
firePendingChanged();
return true;
},
findAll(query: InteractionQuery = {}): readonly Interaction[] {
return [...records().values()].filter((record) => matches(record, query));
},
findOne(query: InteractionQuery): Interaction | undefined {
return [...records().values()].find((record) => matches(record, query));
},
wait<TResponse>(id: string, opts?: { timeoutMs?: number }): Promise<TResponse> {
const record = records().get(id);
if (record === undefined) {
return Promise.reject(new Error(`Interaction "${id}" does not exist`));
}
if (record.resolved) return Promise.resolve(record.response as TResponse);
return new Promise<TResponse>((resolve, reject) => {
const waiter: Waiter = {
resolve: resolve as (response: unknown) => void,
reject,
timer:
opts?.timeoutMs === undefined
? undefined
: setTimeout(() => {
const entries = waiters.get(id);
if (entries !== undefined) {
const remaining = entries.filter((entry) => entry !== waiter);
if (remaining.length === 0) waiters.delete(id);
else waiters.set(id, remaining);
}
reject(new Error(`Timed out waiting for interaction "${id}"`));
}, opts.timeoutMs),
};
const entries = waiters.get(id);
if (entries === undefined) waiters.set(id, [waiter]);
else entries.push(waiter);
});
},
onDidChangePending(listener: (event: InteractionPendingChangedEvent) => void): () => void {
changeListeners.add(listener);
return () => {
changeListeners.delete(listener);
};
},
onDidResolve(listener: (event: InteractionResolution) => void): () => void {
resolveListeners.add(listener);
return () => {
resolveListeners.delete(listener);
};
},
attachAgent(agentId: string, sessionId: string, dispatch: InteractionAgentDispatch): void {
agentDispatchers.set(`${sessionId}:${agentId}`, dispatch);
},
detachAgent(agentId: string, sessionId: string): void {
agentDispatchers.delete(`${sessionId}:${agentId}`);
},
purgeSession(sessionId: string): void {
const purged = [...records().values()].filter(
(record) => record.tags[INTERACTION_TAG_SESSION_ID] === sessionId,
);
for (const record of purged) {
if (record.resolved) continue;
const response: InteractionCancellation = { cancelled: true, reason: 'agent_closed' };
facade.respond(record.id, response);
}
actor.send({ type: 'interaction.purge', sessionId });
for (const record of purged) recentlyResolved.delete(record.id);
for (const key of agentDispatchers.keys()) {
if (key.startsWith(`${sessionId}:`)) agentDispatchers.delete(key);
}
},
stop(): void {
for (const record of records().values()) {
if (record.resolved) continue;
const response: InteractionCancellation = { cancelled: true, reason: 'agent_closed' };
actor.send({ type: 'interaction.resolve', id: record.id, response });
}
requestedSubscription.unsubscribe();
subscription.unsubscribe();
changeListeners.clear();
resolveListeners.clear();
agentDispatchers.clear();
},
};
return facade;
}
export const interactions: InteractionFacade = createDefaultInteractionFacade();
function createDefaultInteractionFacade(): InteractionFacade {
const actor = createActor(createInteractionMachine());
actor.start();
return createInteractionFacade(actor);
}
|