mirror of
https://github.com/deepseek-ai/deepseek-harness
synced 2026-08-15 21:04:50 +00:00
1172 lines
51 KiB
TypeScript
1172 lines
51 KiB
TypeScript
/**
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* Event-sourced session service: append-only session log, in-memory store, and
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* the derived LLM message history. Persistence is a plugin concern (subscribe
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* to `session/event`, drain on `session/flush`).
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*
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* @module @deepseek-ai/dsh-session
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*/
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import { Context, Service } from 'cordis'
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import { isAbsolute } from 'node:path'
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import { deepFreeze } from '@deepseek-ai/dsh-llm'
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import { scopeOf, scopeTarget } from '@deepseek-ai/dsh-scope'
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import type { Scoped } from '@deepseek-ai/dsh-scope'
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import type { Message } from '@deepseek-ai/dsh-llm'
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import { SESSION_FORMAT_VERSION, SessionId } from './types.ts'
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import type { TypeRTLookup } from '@deepseek-ai/dsh-type-meta'
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import type { CreateSessionOptions, EpochHeader, PrepareSessionOptions, RequestContext, SessionEvent, SessionEventMap, SessionEventType, SessionHeader, SurfaceIntent, SurfaceEventType } from './types.ts'
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import { snapshotJsonValue } from './json.ts'
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import { deriveEventMessage, SurfaceManager } from './surface.ts'
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import type { SessionSurface } from './surface.ts'
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import { foldRequestHeader } from './request-header.ts'
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export * from './types.ts'
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export { SessionPreparation } from './preparation.ts'
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export type { SessionPreparationOptions } from './preparation.ts'
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export type { AssistantMessage, ToolResultMessage, UserMessage } from '@deepseek-ai/dsh-llm'
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export { isJsonValue, snapshotJsonValue } from './json.ts'
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export type { JsonValue } from './json.ts'
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export { interruptedTurnClosers, lastActivityTime, TOOL_NOT_STARTED, TOOL_OUTCOME_UNKNOWN } from './repair.ts'
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export { decodeStorageRecord, packChunkRuns } from './chunk-rows.ts'
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export type { ChunkRow, StorageRecord } from './chunk-rows.ts'
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export type { SessionSurface, SurfaceFoldReplacement, SurfaceFoldResult } from './surface.ts'
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export { deriveEventMessage, foldSurface, isAppendSurfaceEvent, isReplacementSurfaceEvent, isSurfaceEvent, isSurfaceEligibleType } from './surface.ts'
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export { canonicalHeader, foldRequestHeader, headerEquals } from './request-header.ts'
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/**
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* Find the latest closed turn that entered at least one model step, ignoring
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* balanced no-step turns produced by rejection, empty input, or cancellation.
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* @param events - session events, or an owned suffix, to inspect.
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* @returns the latest matching turn end, or `undefined`.
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*/
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export function findLastMessageTurnEnd(
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events: readonly SessionEvent[],
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): SessionEvent<'turn/end'> | undefined {
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const steppedTurns = new Set<number>()
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let latest: SessionEvent<'turn/end'> | undefined
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for (const event of events) {
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if (event.type === 'step/start') {
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steppedTurns.add(event.data.turn)
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continue
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}
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if (event.type === 'turn/end' && steppedTurns.delete(event.data.turn)) latest = event
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}
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return latest
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}
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declare module 'cordis' {
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interface Context {
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sessions: SessionStore
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}
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interface Events {
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/**
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* Creation announcement during session publication. A synchronous throw vetoes and rolls
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* back with a paired disposal; detach requested during dispatch is deferred.
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* A returned-promise rejection is logged but cannot retroactively veto this
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* synchronous boundary.
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* Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners
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* receive only sessions entered through that agent's context.
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* @param session - the session just entered and announced.
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* @dshScopeScan unsupported
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* @mode emit
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*/
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'session/created'(this: Scoped<Session>, session: Session): void
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/**
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* Emitted once when an announced session leaves the store, including
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* publication rollback, but never for an entry whose creation announcement
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* did not begin. Listener failures are logged and contained.
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* Scope-filtered dispatch (`@deepseek-ai/dsh-scope`) reuses the owner scope.
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* @param session - the session that is no longer live in the store.
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* @dshScopeScan unsupported
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* @mode emit
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*/
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'session/disposed'(this: Scoped<Session>, session: Session): void
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/**
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* Post-commit, fire-and-forget append feed. The listener snapshot resolves
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* before the log push, but callbacks run after it; observer failures are
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* logged and contained without making the committed append fail.
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* Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners
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* receive only events from sessions entered through that agent's context.
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* @param session - the session whose log grew.
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* @param event - the appended event, exactly as recorded.
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* @dshScopeScan unsupported
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* @mode emit
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*/
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'session/event'(this: Scoped<Session>, session: Session, event: SessionEvent): void
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/**
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* Awaited parallel durability checkpoint: every listener runs and the
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* caller awaits all of them, with no waterfall veto. Scope-filtered dispatch
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* (`@deepseek-ai/dsh-scope`) reuses the session's owner scope.
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* @param session - the session whose buffered events must reach durable storage.
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* @dshScopeScan unsupported
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* @mode parallel
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*/
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'session/flush'(this: Scoped<Session>, session: Session): Promise<void> | void
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}
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}
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declare module '@deepseek-ai/dsh-type-meta' {
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interface TypeRTLookupMap {
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session: TypeRTLookup<Session, SessionId>
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}
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}
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/** Validate and freeze one detached creation header in place. */
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function validateSessionHeader(id: SessionId, input: unknown): SessionHeader {
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if (input === null || typeof input !== 'object' || Array.isArray(input)) {
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throw new Error('session header is not a plain JSON record')
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}
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const record = input as Record<string, unknown>
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if (record.version !== SESSION_FORMAT_VERSION) {
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throw new Error(`session header version must be ${SESSION_FORMAT_VERSION}, got ${String(record.version)}`)
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}
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if (record.id !== id) {
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throw new Error(`session header id "${String(record.id)}" does not match session id "${id}"`)
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}
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if (typeof record.createdAt !== 'number'
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|| !Number.isSafeInteger(record.createdAt)
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|| record.createdAt < 0) {
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throw new Error('session header createdAt must be a non-negative safe integer')
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}
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if (record.cwd !== undefined) {
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if (typeof record.cwd !== 'string') throw new Error('session header cwd must be a string')
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if (!isAbsolute(record.cwd)) {
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throw new Error(`session header cwd must be an absolute path, got "${record.cwd}"`)
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}
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}
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if (record.parentSession !== undefined && typeof record.parentSession !== 'string') {
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throw new Error('session header parentSession must be a string')
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}
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if (record.seedLength !== undefined
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&& (typeof record.seedLength !== 'number' || !Number.isSafeInteger(record.seedLength) || record.seedLength < 0)) {
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throw new Error('session header seedLength must be a non-negative safe integer')
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}
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if (record.origin !== undefined && record.origin !== 'subagent') {
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throw new Error('session header origin must be "subagent"')
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}
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if (record.delegationDepth !== undefined
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&& (typeof record.delegationDepth !== 'number' || !Number.isSafeInteger(record.delegationDepth) || record.delegationDepth < 0)) {
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throw new Error('session header delegationDepth must be a non-negative safe integer')
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}
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return deepFreeze(record as unknown as SessionHeader)
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}
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/** Validate and freeze one exclusively owned persistence header in place. */
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function validateRestoredSessionHeader(id: SessionId, input: unknown): SessionHeader {
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if (input !== null && typeof input === 'object' && !Array.isArray(input)) {
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const prototype = Reflect.getPrototypeOf(input)
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if (prototype !== Object.prototype && prototype !== null) {
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throw new Error('session header is not a plain JSON record')
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}
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}
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return validateSessionHeader(id, input)
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}
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/** Detach, validate, and freeze the creation metadata published by a session. */
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function snapshotSessionHeader(id: SessionId, source?: SessionHeader): SessionHeader {
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const input: unknown = source === undefined
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? { version: SESSION_FORMAT_VERSION, id, createdAt: Date.now() }
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: source
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const snapshot = snapshotJsonValue(input)
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if (snapshot === undefined) throw new Error('session header is not losslessly JSON-serializable')
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return validateSessionHeader(id, snapshot)
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}
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/**
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* Validate an exclusively owned event and deeply freeze its identified message
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* without copying the event. The caller transfers an object graph that no
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* producer retains and that shares no mutable children with another event.
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* Use {@link snapshotSessionEvent} when exclusive ownership is not guaranteed.
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* @param event - exclusively owned event imported across a trusted boundary.
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* @returns the same event object with a validated, deeply frozen message.
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*/
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export function adoptSessionEvent<T extends SessionEvent>(event: T): T {
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assertMessageEventShape(
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event,
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`session event at seq ${event.seq}`,
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)
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switch (event.type) {
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case 'user/message':
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deepFreeze(event.data)
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break
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case 'assistant/message':
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case 'tool/result':
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deepFreeze(event.data.message)
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break
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default:
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// SessionEventMap is merge-extensible; plugin-owned events carry no core message.
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break
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}
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return event
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}
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/**
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* Detach one event while preserving deep immutability for its identified message.
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* @param event - event imported across a query or persistence boundary.
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* @returns a detached event snapshot with a validated, deeply frozen message.
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*/
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export function snapshotSessionEvent<T extends SessionEvent>(event: T): T {
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return adoptSessionEvent(structuredClone(event))
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}
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/** Deep-freeze one acyclic JSON tree without consuming the JavaScript call stack. */
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function freezeRestoredObject<T extends object>(value: T): T {
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const pending: object[] = [value]
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while (pending.length > 0) {
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// The non-empty check proves an object remains to visit.
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// oxlint-disable-next-line typescript/no-non-null-assertion
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const current = pending.pop()!
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Object.freeze(current)
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for (const key in current) {
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const child = (current as Record<string, unknown>)[key]
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if (child !== null && typeof child === 'object') pending.push(child)
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}
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}
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return value
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}
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/** Validate the fixed event envelope after one-pass JSON materialization. */
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function assertSessionEventEnvelope(value: Record<string, unknown>, index: number): asserts value is SessionEvent {
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const event = value
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if (event['type'] === 'request/header-delta') {
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throw new Error(`seed event at index ${index} uses unsupported legacy request/header-delta format`)
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}
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for (const key in event) {
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switch (key) {
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case 'type':
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case 'seq':
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case 'time':
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case 'data':
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case 'surfaceOp':
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case 'sourceEventSeqs':
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break
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default:
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throw new Error(`seed event at index ${index} has an invalid event envelope`)
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}
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}
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const type = event['type']
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const seq = event['seq']
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const time = event['time']
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if (typeof type !== 'string'
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|| typeof seq !== 'number' || !Number.isSafeInteger(seq) || seq < 0
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|| typeof time !== 'number' || !Number.isSafeInteger(time)
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|| event['data'] === undefined) {
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throw new Error(`seed event at index ${index} has an invalid event envelope`)
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}
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switch (type) {
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case 'request/header':
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case 'user/message':
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case 'assistant/message':
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case 'tool/result':
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assertCurrentLlmShape(event, index)
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break
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}
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}
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/** Reject obsolete request headers and malformed messages at the seed/load boundary. */
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function assertCurrentLlmShape(event: Record<string, unknown>, index: number): void {
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const data = event['data']
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const record = typeof data === 'object' && data !== null
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? data as Record<string, unknown>
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: undefined
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if (event['type'] === 'request/header') {
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const header = record?.['header']
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const headerRecord = typeof header === 'object' && header !== null && !Array.isArray(header)
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? header as Record<string, unknown>
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: undefined
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const config = headerRecord?.['config']
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if (!hasProviderModel(config)) throw new Error(`seed request/header at index ${index} lacks provider/model`)
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const configRecord = config as Record<string, unknown>
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const reasoningEffort = configRecord['reasoningEffort']
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if (reasoningEffort !== undefined
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&& (typeof reasoningEffort !== 'string' || reasoningEffort.length === 0)) {
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throw new Error(`seed request/header at index ${index} has an invalid reasoningEffort`)
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}
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assertAdapterDefaults(headerRecord?.['adapterDefaults'], configRecord, index)
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}
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const type = event['type']
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if (type !== 'user/message' && type !== 'assistant/message'
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&& type !== 'tool/result') return
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assertMessageEventShape(event, `seed ${type} at index ${index}`)
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}
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const allowedAdapterKeys = new Set(['reasoningEffort', 'maxTokens'])
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/** Validate adapter-default provenance imported from a durable request header. */
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function assertAdapterDefaults(
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value: unknown,
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config: Record<string, unknown>,
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index: number,
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): void {
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if (value === undefined) return
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if (typeof value !== 'object' || value === null || Array.isArray(value)) {
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throw new Error(`seed request/header at index ${index} has invalid adapterDefaults`)
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}
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const defaults = value as Record<string, unknown>
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if (Object.keys(defaults).some(key => !allowedAdapterKeys.has(key))
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|| Object.values(defaults).some(marker => marker !== true)
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|| defaults['reasoningEffort'] === true && config['reasoningEffort'] === undefined
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|| defaults['maxTokens'] === true && config['maxTokens'] === undefined) {
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throw new Error(`seed request/header at index ${index} has invalid adapterDefaults`)
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}
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}
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/** Validate only the event-specific invariants needed to safely replay a message. */
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function assertMessageEventShape(event: Record<string, unknown>, subject: string): void {
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const type = event['type']
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if (type !== 'user/message' && type !== 'assistant/message'
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&& type !== 'tool/result') return
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const data = event['data']
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const record = typeof data === 'object' && data !== null
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? data as Record<string, unknown>
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: undefined
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const message = type === 'user/message' ? record : record?.['message']
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if (typeof message !== 'object' || message === null
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|| typeof (message as Record<string, unknown>)['id'] !== 'string'
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|| (message as Record<string, unknown>)['id'] === '') {
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throw new Error(`${subject} lacks an identified message`)
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}
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const messageRecord = message as Record<string, unknown>
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const expectedRole = type === 'assistant/message' ? 'assistant' : 'user'
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if (messageRecord['role'] !== expectedRole) {
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throw new Error(`${subject} message must have role "${expectedRole}"`)
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}
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const source = messageRecord['source']
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if (typeof source !== 'object' || source === null
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|| typeof (source as Record<string, unknown>)['kind'] !== 'string'
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|| (source as Record<string, unknown>)['kind'] === '') {
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throw new Error(`${subject} message has invalid source`)
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}
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if (!Array.isArray(messageRecord['content'])) {
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throw new Error(`${subject} message has invalid content`)
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}
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const sourceRecord = source as Record<string, unknown>
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if (type === 'assistant/message') {
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if (sourceRecord['kind'] !== 'model' || !hasProviderModel(sourceRecord)) {
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throw new Error(`${subject} message must have model source`)
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}
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return
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}
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if (type !== 'tool/result') return
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if (sourceRecord['kind'] !== 'tool'
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|| typeof sourceRecord['callId'] !== 'string'
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|| sourceRecord['callId'] === '') {
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throw new Error(`${subject} message must have tool source`)
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}
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const content = messageRecord['content'] as unknown[]
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const block = content[0]
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if (content.length !== 1 || typeof block !== 'object' || block === null
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|| (block as Record<string, unknown>)['type'] !== 'tool-result'
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|| !Array.isArray((block as Record<string, unknown>)['content'])) {
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throw new Error(`${subject} message must contain one tool-result block`)
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}
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if ((block as Record<string, unknown>)['toolCallId'] !== sourceRecord['callId']) {
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throw new Error(`${subject} message has mismatched tool call ids`)
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}
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}
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/** Whether an unknown value carries the current provider/model pair. */
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function hasProviderModel(value: unknown): boolean {
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if (typeof value !== 'object' || value === null) return false
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const pair = value as Record<string, unknown>
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return typeof pair['provider'] === 'string' && pair['provider'].length > 0
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&& typeof pair['model'] === 'string' && pair['model'].length > 0
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}
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/** Reject request-header vocabulary removed with the legacy delta codec. */
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function assertSupportedRequestHeader(type: string, data: unknown, location: string): void {
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if (type === 'request/header-delta') {
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throw new Error(`${location} uses unsupported legacy request/header-delta format`)
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}
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if (type === 'request/header'
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&& data !== null && typeof data === 'object' && !Array.isArray(data)
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&& (data as Record<string, unknown>)['reason'] === 'fallback') {
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throw new Error(`${location} uses unsupported legacy request/header reason "fallback"`)
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}
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}
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type SessionCallback = (...args: unknown[]) => unknown
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|
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/** Resolve one listener snapshot, including Cordis's internal dispatch checks. */
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function collectSessionCallbacks(ctx: Context, args: unknown[]): SessionCallback[] {
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return [...ctx.events.dispatch('emit', args)] as SessionCallback[]
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}
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|
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/** Invoke one resolved observe-only listener snapshot with per-listener containment. */
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function invokeContainedSessionObservers(
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ctx: Context,
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name: 'session/event' | 'session/disposed',
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id: SessionId,
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args: unknown[],
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callbacks: SessionCallback[],
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): void {
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for (const callback of callbacks) {
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try {
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const returned: unknown = callback(...args)
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void Promise.resolve(returned).catch((error: unknown) => {
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ctx.logger.warn(`session "${id}": ${name} listener rejected: ${String(error)}`)
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})
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} catch (error: unknown) {
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ctx.logger.warn(`session "${id}": ${name} listener threw: ${String(error)}`)
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}
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}
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}
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|
|
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/** All mutable lifecycle state for one exact store entry. */
|
|
interface SessionEntry {
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readonly id: SessionId
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readonly session: Session
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readonly carrier: Scoped<Session>
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readonly emitCtx: Context
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announced: boolean
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announcing: boolean
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appending: boolean
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detachRequested: boolean
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detach(): void
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}
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|
|
/** Store attachment for the append path; module-private to keep Session store-agnostic publicly. */
|
|
const attachments = new WeakMap<Session, SessionEntry>()
|
|
|
|
/**
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* An event-sourced session: an append-only log of {@link SessionEvent}s.
|
|
*
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|
* Plain class (not a Service) — create live instances via
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* `ctx.sessions.create()` and detached instances via {@link create}.
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|
* Seeding with an existing event log replays/forks a session.
|
|
* @typert object
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|
*/
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|
export class Session {
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private log: SessionEvent[] = []
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|
/** Single incremental owner of surface acceptance and projection state. */
|
|
private readonly surfaceManager = new SurfaceManager(this.log)
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|
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/** The ordered surface over this session's event log. */
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get surface(): SessionSurface {
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return this.surfaceManager
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}
|
|
|
|
/**
|
|
* Detached, deep-frozen creation metadata (format version, cwd, lineage,
|
|
* seed boundary). Supplied by the store via `ctx.sessions.create()`. When a
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|
* `Session` is created without a store-owned header, a minimal header is
|
|
* synthesized (stamped with the current {@link SESSION_FORMAT_VERSION}) so
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|
* `session.header` is always present. Kept out of the event log — it is a
|
|
* storage concern, not replayable conversation state.
|
|
*/
|
|
readonly header: SessionHeader
|
|
|
|
/** The session identity, derived from its durable header's single copy. */
|
|
get id(): SessionId {
|
|
return this.header.id
|
|
}
|
|
|
|
/**
|
|
* The first seq appended IN THIS PROCESS: the length of the constructor
|
|
* seed (0 without one). Events with smaller seq values entered through
|
|
* construction — replay, fork, or resume — and were never published on the
|
|
* `session/event` firehose (constructor seeds do not emit), so consumers
|
|
* that replay the log as a publication substitute (telemetry adoption)
|
|
* start here. Distinct from `header.seedLength`, the DURABLE fork-lineage
|
|
* boundary: a resumed session's constructor seed is its full stored log,
|
|
* while its header keeps the original fork value — this field is the
|
|
* in-process construction fact.
|
|
*
|
|
* Not persisted itself: a seeded session projects it into the log as the
|
|
* `session/end-seed` event, which is what a consumer reading STORED history
|
|
* reads. Locate the LAST such event, not necessarily one at this seq — a
|
|
* seed already ending in one is not re-marked, so reopening an untouched
|
|
* session leaves that event at a smaller seq than `firstLiveSeq`. Prefer
|
|
* this field in-process: it is exact before the marker reaches storage.
|
|
*
|
|
* When this lifecycle appends the marker, it occupies this seq before the
|
|
* store attaches and therefore does not publish either. Otherwise this seq
|
|
* holds an ordinary published write.
|
|
*/
|
|
readonly firstLiveSeq: number
|
|
|
|
/**
|
|
* Create a detached session by validating and snapshotting borrowed seed
|
|
* events and storage metadata.
|
|
* @param id - session identity.
|
|
* @param seed - optional borrowed replay or fork events.
|
|
* @param header - optional borrowed storage metadata.
|
|
* @returns a detached session.
|
|
*/
|
|
static create(id: SessionId, seed?: readonly SessionEvent[], header?: SessionHeader): Session {
|
|
return new Session(id, seed, header)
|
|
}
|
|
|
|
/**
|
|
* Restore a detached session by taking ownership of fresh persistence values.
|
|
* Storage shape, event envelopes, sequence continuity, surface transitions,
|
|
* and header fields are validated before the graphs are frozen in place.
|
|
* @param id - restored session identity.
|
|
* @param seed - fresh detached events whose ownership is transferred.
|
|
* @param header - fresh detached metadata whose ownership is transferred.
|
|
* @returns a restored detached session.
|
|
*/
|
|
static fromRestore(id: SessionId, seed: readonly SessionEvent[], header: SessionHeader): Session {
|
|
return new Session(id, seed, header, 'restore')
|
|
}
|
|
|
|
private constructor(
|
|
id: SessionId,
|
|
seed?: readonly SessionEvent[],
|
|
header?: SessionHeader,
|
|
mode: 'snapshot' | 'restore' = 'snapshot',
|
|
) {
|
|
const restoredHeader = mode === 'restore'
|
|
? validateRestoredSessionHeader(id, header)
|
|
: undefined
|
|
if (seed !== undefined) {
|
|
// Validate the seed to the SAME invariants `append` enforces, so a
|
|
// replay/fork (`ctx.sessions.create(id, { seed })`) cannot construct a
|
|
// live log that no persistence backend could store: each event's `data`
|
|
// must be JSON-serializable, and `seq` must be contiguous from 0 (the
|
|
// `seq = log.length` contract the whole system relies on). Without this,
|
|
// a bad seed would surface only later as a backend rejection or a silent
|
|
// divergence between the live log and disk.
|
|
for (const [index, source] of seed.entries()) {
|
|
// The seed is a persistence/replay boundary: validate and detach the
|
|
// complete event in one lossless-JSON pass.
|
|
const snapshot = mode === 'restore' ? source : snapshotJsonValue(source)
|
|
if (snapshot === undefined) {
|
|
throw new Error(`seed event at index ${index} is not losslessly JSON-serializable`)
|
|
}
|
|
assertSessionEventEnvelope(snapshot, index)
|
|
assertSupportedRequestHeader(snapshot.type, snapshot.data, `seed event at index ${index}`)
|
|
if (snapshot.seq !== index) {
|
|
throw new Error(`seed event at index ${index} has seq ${snapshot.seq} (expected ${index}); seed must be contiguous from 0`)
|
|
}
|
|
// A seed is accepted incrementally through the same transition as a
|
|
// live append and a full-log fold. The candidate is planned before it
|
|
// enters `log`, so a failure cannot partially mutate the surface.
|
|
try {
|
|
this.surfaceManager.validateNext(snapshot)
|
|
} catch (error: unknown) {
|
|
throw new Error(`invalid seed event at index ${index}: ${error instanceof Error ? error.message : 'invalid surface metadata'}`)
|
|
}
|
|
this.log.push(mode === 'restore' ? freezeRestoredObject(snapshot) : deepFreeze(snapshot))
|
|
}
|
|
}
|
|
this.firstLiveSeq = this.log.length
|
|
this.header = restoredHeader ?? snapshotSessionHeader(id, header)
|
|
// Appended here so the marker is already in `events` when a backend
|
|
// captures the creation seed: no load-time write. Re-marking is skipped
|
|
// because a cold session is resumed on first touch, so repeatedly opening
|
|
// one must not grow its log per open.
|
|
if (seed !== undefined && this.log.at(-1)?.type !== 'session/end-seed') {
|
|
this.append('session/end-seed', {})
|
|
}
|
|
}
|
|
|
|
/** Cached immutable public snapshot of the private append-only log. */
|
|
private eventsSnapshot: readonly SessionEvent[] | undefined
|
|
|
|
/**
|
|
* An immutable snapshot of the append-only event log. The snapshot is reused
|
|
* until the next append; a previously returned array does not grow later.
|
|
* Events and their nested data are deep-frozen at acceptance, so neither a
|
|
* cast nor ordinary JavaScript can rewrite durable history.
|
|
*/
|
|
get events(): readonly SessionEvent[] {
|
|
this.eventsSnapshot ??= Object.freeze([...this.log])
|
|
return this.eventsSnapshot
|
|
}
|
|
|
|
/** The next event's sequence number — always the log length (the `seq = log.length` contiguity contract). */
|
|
get seq(): number {
|
|
return this.log.length
|
|
}
|
|
|
|
/**
|
|
* Append one typed event to the log and synchronously notify observers via
|
|
* the store-owned, module-private publication hooks. The hot path never blocks
|
|
* on I/O — persistence plugins buffer asynchronously. Once the event enters
|
|
* the log, the append is committed: observer failures are logged and
|
|
* contained per listener, so they do not change the return value or prevent
|
|
* later listeners from observing the same accepted event.
|
|
*
|
|
* @param type - The event type (key of {@link SessionEventMap}).
|
|
* @param data - The event payload; must be JSON-serializable.
|
|
* @param opts - Surface metadata: `surfaceOp` controls how the event enters
|
|
* the ordered surface; `sourceEventSeqs` records provenance (the seq
|
|
* numbers of events this one derives from). REQUIRED for
|
|
* {@link SurfaceEventType} events (every message-producing event must
|
|
* declare how it joins the surface, the sole source of derived model
|
|
* history) and
|
|
* rejected by the compiler for non-surface types like `turn/start` or
|
|
* `assistant/chunk`.
|
|
* @returns the logged event — its assigned `seq`/`time` plus the SNAPSHOT of
|
|
* `data` that entered the log, so reading `event.data` back sees the logged
|
|
* value, never the caller's still-mutable input.
|
|
* @throws if `data` or surface metadata is not losslessly JSON-serializable
|
|
* (BigInt, function, symbol, undefined, negative zero, non-finite number,
|
|
* circular reference, sparse array, or an exotic object such as
|
|
* Map/Set/Date/class instance), or when the candidate violates the
|
|
* canonical surface contract (marker shape and eligibility, unique
|
|
* earlier provenance, positional replacement validity, and complete
|
|
* shadowed-node coverage). One recursive pass reads, validates, and
|
|
* copies each nested value once, so a stateful getter cannot supply one value
|
|
* to validation and another to storage. The event log is the durable source
|
|
* of truth, so a bad event fails at the append site rather than later during
|
|
* a backend flush. A synchronous internal dispatch validation failure or an
|
|
* append reentered while this acceptance/publication boundary is open also
|
|
* rejects before the log changes.
|
|
*/
|
|
append<T extends SessionEventType>(
|
|
type: T,
|
|
data: SessionEventMap[T],
|
|
...opts: T extends SurfaceEventType ? [opts: SurfaceIntent] : []
|
|
): SessionEvent<T> {
|
|
const surfaceOpts: SurfaceIntent | undefined = opts[0]
|
|
const surfaceMetadata = {
|
|
...surfaceOpts?.sourceEventSeqs === undefined ? {} : { sourceEventSeqs: surfaceOpts.sourceEventSeqs },
|
|
...surfaceOpts?.surfaceOp === undefined ? {} : { surfaceOp: surfaceOpts.surfaceOp },
|
|
}
|
|
const dataSnapshot = snapshotJsonValue(data)
|
|
if (dataSnapshot === undefined) {
|
|
throw new Error(`session event "${type}" carries non-JSON-serializable data`)
|
|
}
|
|
assertSupportedRequestHeader(type, dataSnapshot, `session event "${type}"`)
|
|
const surfaceMetadataSnapshot = snapshotJsonValue(surfaceMetadata)
|
|
if (surfaceMetadataSnapshot === undefined) {
|
|
throw new Error(`session event "${type}" carries non-JSON-serializable surface metadata`)
|
|
}
|
|
const entry = attachments.get(this)
|
|
if (entry?.appending) {
|
|
throw new Error('session append cannot reenter while another append is being published')
|
|
}
|
|
const event = deepFreeze({
|
|
type,
|
|
seq: this.log.length,
|
|
time: Date.now(),
|
|
data: dataSnapshot,
|
|
...(surfaceMetadataSnapshot as { surfaceOp?: unknown; sourceEventSeqs?: unknown }),
|
|
} as unknown as SessionEvent<T>)
|
|
this.surfaceManager.validateNext(event as SessionEvent)
|
|
|
|
if (entry !== undefined) entry.appending = true
|
|
try {
|
|
let callbacks: SessionCallback[] | undefined
|
|
const callbackArgs: unknown[] = [this, event]
|
|
if (entry !== undefined) {
|
|
callbacks = collectSessionCallbacks(entry.emitCtx, [entry.carrier, 'session/event', ...callbackArgs])
|
|
}
|
|
this.log.push(event as SessionEvent)
|
|
this.eventsSnapshot = undefined
|
|
if (callbacks !== undefined && entry !== undefined) {
|
|
invokeContainedSessionObservers(entry.emitCtx, 'session/event', entry.id, callbackArgs, callbacks)
|
|
}
|
|
return event
|
|
} finally {
|
|
if (entry !== undefined) {
|
|
entry.appending = false
|
|
if (entry.detachRequested && !entry.announcing) entry.detach()
|
|
}
|
|
}
|
|
}
|
|
|
|
/** Cached fold of the request-header events — see {@link requestHeader}. */
|
|
private headerFold: EpochHeader | undefined
|
|
/** Log position (events consumed) the header fold has reached. */
|
|
private headerFoldSeq = 0
|
|
|
|
/**
|
|
* The {@link EpochHeader} in force after the log's last header event — the
|
|
* header the NEXT request will be compared against — or undefined before
|
|
* the first `request/header` snapshot. The live, incrementally-maintained
|
|
* form of `foldRequestHeader(session.events)`: each header event is folded
|
|
* once, when first seen, so a per-step read costs O(new events).
|
|
* @returns the folded header, or undefined when no header event exists yet.
|
|
*/
|
|
requestHeader(): EpochHeader | undefined {
|
|
if (this.headerFoldSeq < this.log.length) {
|
|
// Frozen on update: the fold is session state exposed by reference — a
|
|
// consumer mutating it in place (instead of building a replacement)
|
|
// would desync every later comparison against the log, so mutation
|
|
// throws instead.
|
|
this.headerFold = deepFreeze(foldRequestHeader(this.log.slice(this.headerFoldSeq), this.headerFold))
|
|
this.headerFoldSeq = this.log.length
|
|
}
|
|
return this.headerFold
|
|
}
|
|
|
|
/** Cached fold of `request/context` events. */
|
|
private contextFold: RequestContext | undefined
|
|
private contextFoldSeq = 0
|
|
|
|
/**
|
|
* Return the latest resolved route metadata, or `undefined` before the first
|
|
* `request/context` event. Each event is folded once.
|
|
* @returns the latest immutable route metadata.
|
|
*/
|
|
requestContext(): RequestContext | undefined {
|
|
if (this.contextFoldSeq < this.log.length) {
|
|
for (const event of this.log.slice(this.contextFoldSeq)) {
|
|
if (event.type === 'request/context') this.contextFold = deepFreeze({ ...event.data })
|
|
}
|
|
this.contextFoldSeq = this.log.length
|
|
}
|
|
return this.contextFold
|
|
}
|
|
|
|
/** The derived-message cache: frozen projections, extended per unseen node. */
|
|
private derived: Message[] = []
|
|
/** Surface position (nodes projected) the cache has reached. */
|
|
private derivedNodes = 0
|
|
/** {@link SurfaceManager.replaceGeneration} the cache was built under. */
|
|
private derivedGeneration = 0
|
|
|
|
/**
|
|
* Derive the LLM message history by walking the ordered sequences of
|
|
* message-producing events maintained by `surfaceOp` markers. The
|
|
* surface is the single source of derived history: every message-producing
|
|
* append records its `surfaceOp`, so a raw event with no marker (a chunk, a
|
|
* turn boundary) is correctly absent, and a compaction `replace` deletes the
|
|
* shadowed nodes from the derivation. The projection rules are
|
|
* {@link deriveEventMessage}, folded per node.
|
|
*
|
|
* CACHED: each surface node is projected exactly once, when first seen — a
|
|
* call costs O(new nodes), and a surface rewrite (a `replace`;
|
|
* {@link SessionSurface.replaceGeneration}) rebuilds. The returned array is
|
|
* a fresh snapshot per call (later appends never grow an array a caller
|
|
* already holds); the `Message` objects in it are SHARED and **deep-frozen**.
|
|
* Their content reuses the already frozen durable event data, so the cache
|
|
* needs no second deep clone and consumers still cannot mutate the log.
|
|
* @returns a fresh array of the shared, frozen derived history.
|
|
*/
|
|
deriveMessages(): Message[] {
|
|
const surface = this.surface
|
|
const nodes = surface.nodes
|
|
const generation = surface.replaceGeneration
|
|
if (generation !== this.derivedGeneration) {
|
|
this.derived = []
|
|
this.derivedNodes = 0
|
|
this.derivedGeneration = generation
|
|
}
|
|
for (const seq of nodes.slice(this.derivedNodes)) {
|
|
// Surface sequences are built from this.log — seq is always a valid
|
|
// index by construction. The non-null assertion expresses that invariant.
|
|
// oxlint-disable-next-line typescript/no-non-null-assertion
|
|
const msg = this.deriveEventMessage(this.log[seq]!)
|
|
// A surface node is one of the five message-producing types, but an
|
|
// empty-content assistant/message (a max-tokens step that hosts only
|
|
// usage) derives to null and must not enter the transcript.
|
|
if (msg) this.derived.push(msg)
|
|
}
|
|
this.derivedNodes = nodes.length
|
|
return [...this.derived]
|
|
}
|
|
|
|
/**
|
|
* Instance face of the pure per-node `deriveEventMessage` export from
|
|
* `surface.ts`.
|
|
* @param event - the event to project.
|
|
* @returns the derived message, or null when the event produces none.
|
|
*/
|
|
deriveEventMessage(event: SessionEvent): Message | null {
|
|
return deriveEventMessage(event)
|
|
}
|
|
}
|
|
|
|
/** A fork source: either the live session object or its live store id. */
|
|
export type SessionForkSource = Session | SessionId
|
|
|
|
/**
|
|
* Rejection codes for session forking: the fork source id is unknown to the
|
|
* live store (`SESSION_NOT_FOUND`) or names a session object that is not the
|
|
* store's live instance (`SESSION_NOT_LIVE`); the requested child id is
|
|
* already taken (`SESSION_ALREADY_EXISTS`); the boundary is not a contiguous
|
|
* existing seq (`INVALID_BOUNDARY`); or the selected prefix ends inside an
|
|
* open turn (`OPEN_TURN`).
|
|
*/
|
|
export type SessionForkErrorCode =
|
|
| 'SESSION_NOT_FOUND'
|
|
| 'SESSION_NOT_LIVE'
|
|
| 'SESSION_ALREADY_EXISTS'
|
|
| 'INVALID_BOUNDARY'
|
|
| 'OPEN_TURN'
|
|
|
|
/** Typed error for session fork rejections. */
|
|
export class SessionForkError extends Error {
|
|
constructor(message: string, public readonly code: SessionForkErrorCode) {
|
|
super(message)
|
|
this.name = 'SessionForkError'
|
|
}
|
|
}
|
|
|
|
/**
|
|
* In-memory session store (`ctx.sessions`).
|
|
*
|
|
* Persistence is intentionally not implemented here — persistence plugins
|
|
* subscribe to `session/event` and flush on `session/flush` / dispose.
|
|
*/
|
|
export class SessionStore extends Service {
|
|
private store = new Map<SessionId, SessionEntry>()
|
|
private counter = 0
|
|
|
|
constructor(ctx: Context) {
|
|
super(ctx, 'sessions')
|
|
ctx.inject(['typert'], (typeCtx) => {
|
|
typeCtx.typert.lookups.register('session', {
|
|
parameter: 'session',
|
|
wire: 'sessionId',
|
|
hostTypeSymbol: '@deepseek-ai/dsh-session#Session',
|
|
wireTypeSymbol: '@deepseek-ai/dsh-session/types#SessionId',
|
|
resolve: sessionId => this.get(sessionId),
|
|
})
|
|
})
|
|
}
|
|
|
|
/**
|
|
* Create a session owned by the calling fiber: disposing that fiber stops
|
|
* event notification and removes the session from the store. `options.seed`
|
|
* populates the session with a copy of those events (replay/fork);
|
|
* `options.meta` attaches creation metadata (validated absolute `cwd`, seed
|
|
* and parent lineage, and delegation depth) as the immutable
|
|
* {@link SessionHeader} (the store fills `version`/`id`/`createdAt`).
|
|
*
|
|
* For an agent whose session must be torn down IN ORDER with its loop (so the
|
|
* loop's final events are published before the store attachment ends), do NOT use this
|
|
* — fold the session lifecycle into the agent's own effect via
|
|
* {@link prepare} + {@link enter} + {@link announce} (see
|
|
* `dsh-agent-loop`'s creation transaction).
|
|
*
|
|
* @param id - the session id; omitted, the store mints `session-<n>`.
|
|
* @param options - seed events and/or creation metadata for the header.
|
|
* @returns the live session, already entered and announced.
|
|
* @throws if a session with `id` already exists, metadata is not a plain
|
|
* lossless-JSON record with valid scalar fields, or `meta.cwd` is a
|
|
* non-absolute path (storage backends key directories off it).
|
|
*/
|
|
create(id?: SessionId, options?: CreateSessionOptions): Session {
|
|
const session = this.prepare(id, options)
|
|
// Single effect owned by the calling fiber. Yield the detach BEFORE
|
|
// announcing so a throwing `session/created` listener rolls the attach back
|
|
// (the generator effect disposes already-yielded disposers on a throw)
|
|
// instead of leaking the store entry and its publication hooks.
|
|
this.ctx.effect(function* (this: SessionStore) {
|
|
yield this.enter(session)
|
|
this.announce(session)
|
|
}.bind(this), 'sessions.create()')
|
|
return session
|
|
}
|
|
|
|
/**
|
|
* Build a session WITHOUT entering it into the store — validate the id/cwd and
|
|
* construct the {@link Session} (with its immutable {@link SessionHeader}).
|
|
* Pairs with {@link enter} + {@link announce}: a caller that owns a composite
|
|
* `ctx.effect` (the agent factory) folds the session lifecycle into that ONE
|
|
* effect so a fiber unload tears the session + agent down as a single ORDERED
|
|
* chain rather than as racing sibling effects — which would remove the publication hooks
|
|
* before the driver's closing events commit, dropping them.
|
|
*
|
|
* @param id - the session id; omitted, the store mints `session-<n>`.
|
|
* @param options - seed events and/or creation metadata for the header. With
|
|
* `seedSource: 'persistence'`, metadata and events must be fresh detached
|
|
* graphs whose ownership transfers to this call: they are validated and
|
|
* frozen in place through {@link Session.fromRestore}, so the caller must
|
|
* retain no mutable aliases.
|
|
* @returns the constructed session, NOT yet in the store.
|
|
* @throws if a session with `id` already exists, metadata is not a plain
|
|
* lossless-JSON record with valid scalar fields, or `meta.cwd` is a
|
|
* non-absolute path.
|
|
*/
|
|
prepare(id?: SessionId, options?: PrepareSessionOptions): Session {
|
|
let sessionId: SessionId
|
|
if (id === undefined) {
|
|
do sessionId = SessionId(`session-${++this.counter}`)
|
|
while (this.store.has(sessionId))
|
|
} else {
|
|
sessionId = SessionId(id)
|
|
}
|
|
if (this.store.has(sessionId)) throw new Error(`session "${sessionId}" already exists`)
|
|
if (options?.seedSource === 'persistence') {
|
|
return Session.fromRestore(sessionId, options.seed, options.meta)
|
|
}
|
|
const seed = options?.seed
|
|
const meta = options?.meta
|
|
const header: SessionHeader = {
|
|
version: SESSION_FORMAT_VERSION,
|
|
id: sessionId,
|
|
createdAt: meta?.createdAt ?? Date.now(),
|
|
...meta?.cwd === undefined ? {} : { cwd: meta.cwd },
|
|
...meta?.parentSession === undefined ? {} : { parentSession: meta.parentSession },
|
|
...meta?.seedLength === undefined ? {} : { seedLength: meta.seedLength },
|
|
...meta?.origin === undefined ? {} : { origin: meta.origin },
|
|
...meta?.delegationDepth === undefined ? {} : { delegationDepth: meta.delegationDepth },
|
|
}
|
|
return Session.create(sessionId, seed, header)
|
|
}
|
|
|
|
/**
|
|
* Enter a {@link prepare}d session into the store: install the module-private
|
|
* append publication hooks and add it to the store. Returns the DETACH
|
|
* disposer (hooks + store removal). Does NOT emit `session/created` —
|
|
* the caller yields this disposer inside its effect and THEN calls
|
|
* {@link announce}, so a throwing `session/created` listener rolls the attach
|
|
* back instead of leaking it.
|
|
*
|
|
* Re-checks the id for a duplicate: `prepare` and `enter` are public
|
|
* cross-package primitives and a caller may interleave arbitrary work (or
|
|
* another create) between them, so a stale prepared session must NOT overwrite
|
|
* a live store entry of the same id — its detach disposer would later delete
|
|
* the REAL session. The {@link create} convenience and the agent factory call
|
|
* the two back-to-back so they never trip this, but the public seam cannot
|
|
* assume that.
|
|
*
|
|
* @param session - a {@link prepare}d session not yet in the store.
|
|
* @returns the detach disposer (publication hooks + store removal). When called from
|
|
* a synchronous `session/created` listener, removal and disposal wait until
|
|
* that creation dispatch unwinds.
|
|
* @throws if a session with this id is already in the store.
|
|
*/
|
|
enter(session: Session): () => void {
|
|
const id = session.id
|
|
const carrier = scopeTarget(session, scopeOf(this.ctx))
|
|
// This is the authoritative collision boundary after arbitrary unpublished
|
|
// preparation. Only one exact same-id transaction can publish.
|
|
if (this.store.has(id)) throw new Error(`session "${id}" already exists`)
|
|
if (attachments.has(session)) throw new Error(`session "${id}" is already attached to a store`)
|
|
const entry: SessionEntry = {
|
|
id,
|
|
session,
|
|
carrier,
|
|
emitCtx: this.ctx,
|
|
announced: false,
|
|
announcing: false,
|
|
appending: false,
|
|
detachRequested: false,
|
|
detach: () => { this.detachEntered(entry) },
|
|
}
|
|
this.store.set(id, entry)
|
|
attachments.set(session, entry)
|
|
let entered = true
|
|
const detach = (): void => {
|
|
if (!entered) return
|
|
entered = false
|
|
// A lifecycle listener may own the advanced detach capability. Keep the
|
|
// entry and its publication hooks live until synchronous creation or append
|
|
// publication unwinds, then publish the paired disposal edge.
|
|
if (entry.announcing || entry.appending) {
|
|
entry.detachRequested = true
|
|
return
|
|
}
|
|
entry.detach()
|
|
}
|
|
return detach
|
|
}
|
|
|
|
/** Remove one exact entered session and emit its paired disposal when announced. */
|
|
private detachEntered(entry: SessionEntry): void {
|
|
entry.detachRequested = false
|
|
// A stale capability cannot remove observers or storage belonging to a
|
|
// later same-id lifecycle.
|
|
/* v8 ignore next -- enter() rejects replacement while this single-shot detach capability is live. */
|
|
if (this.store.get(entry.id) !== entry) return
|
|
this.store.delete(entry.id)
|
|
attachments.delete(entry.session)
|
|
if (entry.announced) this.emitDisposed(entry)
|
|
}
|
|
|
|
/** Emit `session/created` exactly once for an {@link enter}ed session (with
|
|
* the carrier {@link enter} captured). Separate from {@link enter} so the
|
|
* caller can yield the detach disposer first (rollback safety — see
|
|
* {@link enter}).
|
|
* @param session - the entered session to announce to listeners.
|
|
* @throws if the session is not live or its announcement already began,
|
|
* including a reentrant call from a creation listener. */
|
|
announce(session: Session): void {
|
|
const entry = this.liveEntryFor(session)
|
|
if (entry.announced || entry.announcing) {
|
|
throw new Error(`session "${entry.id}" was already announced`)
|
|
}
|
|
// Mark before emit: Cordis emit may deliver to earlier listeners and then
|
|
// throw. Rollback must still pair that partial creation with disposal, and
|
|
// a listener cannot recursively create a second lifecycle edge.
|
|
entry.announced = true
|
|
const callbackArgs: unknown[] = [session]
|
|
entry.announcing = true
|
|
try {
|
|
const callbacks = collectSessionCallbacks(this.ctx, [entry.carrier, 'session/created', session])
|
|
for (const callback of callbacks) {
|
|
// Synchronous throws intentionally propagate and veto publication; the
|
|
// yielded detach then emits the paired disposal edge. An async function
|
|
// is nevertheless assignable to a void listener, so observe its returned
|
|
// promise: rejection is too late to roll back and must be logged instead
|
|
// of becoming unhandled.
|
|
const returned: unknown = callback(...callbackArgs)
|
|
void Promise.resolve(returned).catch((error: unknown) => {
|
|
this.ctx.logger.warn(`session "${entry.id}": session/created listener rejected: ${String(error)}`)
|
|
})
|
|
}
|
|
} finally {
|
|
entry.announcing = false
|
|
if (entry.detachRequested && !entry.appending) entry.detach()
|
|
}
|
|
}
|
|
|
|
/** Emit the paired teardown notification with per-listener containment. */
|
|
private emitDisposed(entry: SessionEntry): void {
|
|
const callbackArgs: unknown[] = [entry.session]
|
|
try {
|
|
const callbacks = collectSessionCallbacks(this.ctx, [entry.carrier, 'session/disposed', entry.session])
|
|
invokeContainedSessionObservers(this.ctx, 'session/disposed', entry.id, callbackArgs, callbacks)
|
|
} catch (error: unknown) {
|
|
this.ctx.logger.warn(`session "${entry.id}": session/disposed dispatch threw: ${String(error)}`)
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Dispatch the awaited `session/flush` durability checkpoint for `session`,
|
|
* with the carrier captured at {@link enter}. THE flush entry point: the
|
|
* store owns the carrier, so callers (the checkpoint policy's per-request
|
|
* barrier, goal-session's idle checkpoint, teardown drains, and consumers
|
|
* that flush themselves before reading storage) must come through here
|
|
* rather than dispatch a raw `ctx.parallel('session/flush', …)` — one owner,
|
|
* one spelling, and the scoped-dispatch invariant can pin it.
|
|
* @param session - the session whose buffered events must reach durable storage.
|
|
* @returns whether at least one durability listener participated, after every
|
|
* listener has settled successfully.
|
|
* @throws the first registered listener failure after every listener settles.
|
|
*/
|
|
async flush(session: Session): Promise<boolean> {
|
|
const { carrier } = this.liveEntryFor(session)
|
|
const callbackArgs: unknown[] = [session]
|
|
const callbacks = collectSessionCallbacks(this.ctx, [carrier, 'session/flush', session])
|
|
const results = await Promise.allSettled(callbacks.map((callback) => {
|
|
try {
|
|
return callback(...callbackArgs)
|
|
} catch (error: unknown) {
|
|
// Preserve the listener's exact rejection value; flush is a caller-owned
|
|
// failure boundary, and Cordis listeners may throw arbitrary values.
|
|
// oxlint-disable-next-line typescript/prefer-promise-reject-errors
|
|
return Promise.reject(error)
|
|
}
|
|
}))
|
|
const failure = results.find((result): result is PromiseRejectedResult => result.status === 'rejected')
|
|
if (failure !== undefined) throw failure.reason
|
|
return callbacks.length > 0
|
|
}
|
|
|
|
/** Return the exact live entry; detached/prepared objects reject. */
|
|
private liveEntryFor(session: Session): SessionEntry {
|
|
const entry = attachments.get(session)
|
|
if (entry === undefined || this.store.get(entry.id) !== entry) {
|
|
throw new Error(`session "${session.id}" is not live in this store`)
|
|
}
|
|
return entry
|
|
}
|
|
|
|
/**
|
|
* Look up a live session.
|
|
* @param id - the session id to look up.
|
|
* @returns the session, or undefined when no live session has that id.
|
|
*/
|
|
get(id: SessionId): Session | undefined {
|
|
return this.store.get(id)?.session
|
|
}
|
|
|
|
/**
|
|
* All live sessions, in creation order.
|
|
* @returns a fresh array; mutating it does not affect the store.
|
|
*/
|
|
list(): Session[] {
|
|
return [...this.store.values()].map(entry => entry.session)
|
|
}
|
|
|
|
/**
|
|
* Create a live child session from a stable prefix of a live source.
|
|
* `boundary` is an inclusive source event seq; omitted means the source's
|
|
* current last event. The selected slice may end with a between-turn event
|
|
* but must not end inside an open turn.
|
|
*
|
|
* @param source - Live source session object or id.
|
|
* @param boundary - Inclusive source event seq to fork through; omitted means
|
|
* the source's current last event, and omitted on an empty source forks an
|
|
* empty child.
|
|
* @param childSessionId - Optional child session id; omitted delegates to
|
|
* `SessionStore`'s id policy.
|
|
* @returns The created live child session.
|
|
*/
|
|
fork(source: SessionForkSource, boundary?: number, childSessionId?: SessionId): Session {
|
|
if (childSessionId !== undefined && this.get(childSessionId) !== undefined) {
|
|
throw new SessionForkError(`session "${childSessionId}" already exists`, 'SESSION_ALREADY_EXISTS')
|
|
}
|
|
const liveSource = this._resolveForkSource(source)
|
|
const seed = this._forkSeed(liveSource, boundary)
|
|
return this.create(childSessionId, {
|
|
seed,
|
|
meta: {
|
|
...liveSource.header.cwd !== undefined ? { cwd: liveSource.header.cwd } : {},
|
|
parentSession: liveSource.id,
|
|
seedLength: seed.length,
|
|
},
|
|
})
|
|
}
|
|
|
|
private _forkSeed(session: Session, requestedBoundary: number | undefined): SessionEvent[] {
|
|
const events = session.events
|
|
const lastEvent = events.at(-1)
|
|
let boundary: number
|
|
if (requestedBoundary !== undefined) {
|
|
boundary = requestedBoundary
|
|
} else {
|
|
if (lastEvent === undefined) return []
|
|
boundary = lastEvent.seq
|
|
}
|
|
if (!Number.isSafeInteger(boundary) || boundary < 0) {
|
|
throw new SessionForkError(
|
|
`fork boundary for session "${session.id}" must be a non-negative safe integer, got ${String(boundary)}`,
|
|
'INVALID_BOUNDARY',
|
|
)
|
|
}
|
|
if (boundary >= events.length) {
|
|
const lastSeq = events.at(-1)?.seq
|
|
throw new SessionForkError(
|
|
`fork boundary ${boundary} does not exist in session "${session.id}" (last seq: ${lastSeq ?? 'none'})`,
|
|
'INVALID_BOUNDARY',
|
|
)
|
|
}
|
|
|
|
const boundaryEvent = events[boundary]
|
|
if (boundaryEvent === undefined || boundaryEvent.seq !== boundary) {
|
|
throw new SessionForkError(
|
|
`fork boundary ${boundary} does not match a contiguous event seq in session "${session.id}"`,
|
|
'INVALID_BOUNDARY',
|
|
)
|
|
}
|
|
const lastTurnBoundary = events.slice(0, boundary + 1)
|
|
.findLast(event => event.type === 'turn/start' || event.type === 'turn/end')
|
|
if (lastTurnBoundary?.type === 'turn/start') {
|
|
throw new SessionForkError(
|
|
`fork boundary ${boundary} in session "${session.id}" ends inside open turn ${lastTurnBoundary.data.turn}`,
|
|
'OPEN_TURN',
|
|
)
|
|
}
|
|
|
|
return events.slice(0, boundary + 1)
|
|
}
|
|
|
|
private _resolveForkSource(source: SessionForkSource): Session {
|
|
if (typeof source === 'string') {
|
|
const session = this.get(source)
|
|
if (session === undefined) throw new SessionForkError(`session "${source}" not found`, 'SESSION_NOT_FOUND')
|
|
return session
|
|
}
|
|
|
|
const live = this.get(source.id)
|
|
if (live === undefined) {
|
|
throw new SessionForkError(`session "${source.id}" not found`, 'SESSION_NOT_FOUND')
|
|
}
|
|
if (live !== source) throw new SessionForkError(`session "${source.id}" is not the live store instance`, 'SESSION_NOT_LIVE')
|
|
return source
|
|
}
|
|
|
|
}
|
|
|
|
export default SessionStore
|