# 会话查询

[English](session-query.md) | 中文

本文定义面向优先使用 live 数据的逻辑会话语料库的查询词汇。[接口包（package）](../../packages/session-query/session-query)负责精确读取、来源优先级、关系追踪、语义提取，以及与提供方无关的过滤器；[SQLite 包](../../packages/session-query/session-query-sqlite)负责具体全文索引的生命周期。

源码：[`packages/session-query/session-query/src/types.ts`](../../packages/session-query/session-query/src/types.ts)

## 逻辑记录

`SessionRecord` 由跨语料库列表返回。它独立于克隆后的实时优先 header 暴露源可用性。`SessionEventRecord` 是轻量的原始日志投影；分类使用与 model-history 推导相同的 `foldSurface()` 状态转换。

```ts type-equiv
/** Whether an event is current model context, replaced context, or raw-log-only. */
type SessionEventSurface = 'current' | 'shadowed' | 'log-only'
```

```ts type-equiv
/** Lightweight identity and source availability for one logical session. */
interface SessionRecord {
  /** Cloned session header selected from the live-preferred corpus. */
  header: SessionHeader
  /** Whether the id currently exists in `ctx.sessions`. */
  live: boolean
  /** Whether the active persistence backend currently materializes the id. */
  persisted: boolean
}
```

`SessionLogSnapshot` 是供恢复预检使用的完整原始日志：它脱离运行时，并经过回放验证。`SessionSurfaceSnapshot` 表示一次精确读取的 surface 观测结果，而不是持续保留的订阅。

```ts type-equiv
/** One validated detached observation of a logical session's complete raw log. */
interface SessionLogSnapshot {
  /** Cloned session header selected from the same observation as `events`. */
  session: SessionHeader
  /** Cloned contiguous raw events after persistence repair and replay validation. */
  events: SessionEvent[]
}
```

```ts type-equiv
/** One atomic live-preferred observation of a session's current model surface. */
interface SessionSurfaceSnapshot {
  /** Cloned session header selected from the same corpus observation as `events`. */
  session: SessionHeader
  /** Highest raw-log seq included in the observation, or `null` for an empty log. */
  capturedThroughSeq: number | null
  /** Cloned current surface events in model-history order. */
  events: SurfaceEvent[]
}
```

`SessionTitleObservation` 将同样的原子观测规则应用于标题折叠，使授权消费者能够验证提供标题的源 header。批量读取会按顺序为每个唯一请求 id 返回一个 `SessionTitleObservationResult`：操作失败只影响对应 id，而取消会拒绝整个操作。

```ts type-equiv
/** Latest folded title bound to the same session-header observation. */
interface SessionTitleObservation {
  /** Cloned header selected with the event log used for the title fold. */
  session: SessionHeader
  /** Latest title snapshot, absent when the observed log has no title. */
  title?: SessionTitleSnapshot
}
```

```ts type-equiv
/** One ordered result from a batch title observation. */
type SessionTitleObservationResult =
  | {
    /** Requested session id. */
    sessionId: SessionId
    /** Successful atomic header/title observation. */
    status: 'fulfilled'
    /** Header and optional latest title from one logical source. */
    value: SessionTitleObservation
  }
  | {
    /** Requested session id. */
    sessionId: SessionId
    /** Operational failure isolated to this session. */
    status: 'rejected'
    /** Original failure from logical-source resolution or title folding. */
    reason: unknown
  }
```

```ts type-equiv
/** Lightweight metadata for one event within a logical session. */
interface SessionEventRecord {
  /** Session that owns the event. */
  sessionId: SessionId
  /** Monotonic event seq within the session. */
  seq: number
  /** Discriminant of the session event. */
  type: SessionEventType
  /** Event timestamp in Unix epoch milliseconds. */
  time: number
  /** Event placement in the folded session surface. */
  surface: SessionEventSurface
}
```

## 与提供方无关的过滤器和文档

会话和事件过滤器数组内的各项按逻辑与（AND）组合；单个列表子句中的各值按逻辑或（OR）组合。范围包含两端。事件的 `text` 子句会对提取出的语义文本执行正则表达式扫描：搜索文本按字面量处理，Unicode 字符不区分大小写，空白字符可灵活匹配；该过程与全文搜索提供方无关。

```ts type-equiv
/**
 * One logical-session predicate. A filter array is ANDed; `values` within a
 * clause are ORed.
 */
type SessionResultFilter =
  | { kind: 'id'; values: readonly SessionId[] }
  | { kind: 'cwd'; values: readonly (string | null)[] }
  | ({ kind: 'created-at' } & SessionResultRange)
  | { kind: 'parent'; values: readonly (SessionId | null)[] }
  | { kind: 'availability'; values: readonly SessionAvailability[] }
```

```ts type-equiv
/**
 * One event predicate. A filter array is ANDed; list-valued clauses are ORed.
 * Text is a literal, case-insensitive, whitespace-flexible semantic-text scan.
 */
type SessionEventResultFilter =
  | ({ kind: 'seq' } & SessionResultRange)
  | ({ kind: 'time' } & SessionResultRange)
  | { kind: 'type'; values: readonly SessionEventType[] }
  | { kind: 'surface'; values: readonly SessionEventSurface[] }
  | { kind: 'text'; text: string }
```

```ts type-equiv
/** Searchable semantic document derived from one session event. */
interface SessionEventSearchDocument extends SessionEventRecord {
  /** First-party semantic text used by scan filters and full-text indexes. */
  text: string
}
```

`ctx.sessionQuery.filterSessions(filters)` 会对完整的逻辑会话语料库应用 `SessionResultFilter`；`ctx.sessionQuery.filterEvents(sessionId, filters)` 按 seq 升序返回匹配的文档。消息、推理（reasoning）、工具调用和工具结果、被阻止的提示词、待办事项，以及失败和状态详情会纳入语义文本；结构事件和流分片则不会。

## 全文搜索结果页

整合后的 `ctx.sessionQuery` seam 提供两个全文搜索范围。`searchSessions()` 按匹配度最强的事件对语料库分组；`searchEvents()` 搜索单个会话。请求将不透明游标与规范化后的查询、元数据过滤器和结果数量上限绑定。提供方的元数据过滤器有意不包含事件文本扫描。

```ts type-equiv
/** Provider-owned opaque continuation token returned by session search. */
type SessionSearchCursor = Branded<'SessionSearchCursor'>
```

```ts type-equiv
/** Cross-session full-text search request. */
interface SessionSearchRequest {
  /** Full-text query interpreted as data, never executable FTS syntax. */
  query: string
  /** Logical-session predicates applied before event ranking. */
  sessionFilters?: readonly SessionResultFilter[]
  /** Event predicates applied before event ranking. */
  eventFilters?: readonly SessionEventMetadataFilter[]
  /** Maximum sessions in this page. */
  limit?: number
  /** Opaque cursor returned for the identical normalized request. */
  cursor?: SessionSearchCursor
}
```

```ts type-equiv
/** Within-session full-text search request. */
interface SessionEventSearchRequest {
  /** Session whose live-preferred logical log is searched. */
  sessionId: SessionId
  /** Full-text query interpreted as data, never executable FTS syntax. */
  query: string
  /** Event predicates applied before ranking. */
  filters?: readonly SessionEventMetadataFilter[]
  /** Maximum events in this page. */
  limit?: number
  /** Opaque cursor returned for the identical normalized request. */
  cursor?: SessionSearchCursor
}
```

```ts type-equiv
/** One cursor-paginated result page. */
interface SessionSearchPage<T> {
  /** Results for this page in contract-defined order. */
  items: readonly T[]
  /** Opaque continuation cursor, absent on the final page. */
  nextCursor?: SessionSearchCursor
}
```

与跨会话分组 hit 不同，会话内搜索即使没有命中项，也必须公开它观测到的目标 header。

```ts type-equiv
/** Event-search results bound to the indexed target-session observation. */
interface SessionEventSearchPage extends SessionSearchPage<SessionEventSearchHit> {
  /** Cloned target header from the same indexed generation as `items`. */
  session: SessionHeader
}
```

```ts type-equiv
/** One event full-text search hit with a bounded plain-text excerpt. */
interface SessionEventSearchHit extends SessionEventRecord {
  /** Plain text excerpt selected around the match. */
  snippet: string
}
```

```ts type-equiv
/** One grouped cross-session hit, ranked by its strongest matching event. */
interface SessionSearchHit extends SessionRecord {
  /** Strongest matching event for this session. */
  bestMatch: SessionEventSearchHit
}
```

## 会话谱系

`SessionLineageTrace` 按由近及远的顺序携带已知 parent，并携带一片由直接 descendant 递归嵌套而成的森林。完整性判别字段使已知 root 与缺失 parent 互斥。

```ts type-equiv
/** Recursive descendant node in a session-lineage trace. */
interface SessionLineageNode {
  /** Detached logical-corpus record for this descendant. */
  session: SessionRecord
  /** Direct children, each carrying its own recursive descendants. */
  descendants: SessionLineageNode[]
}
```

```ts type-equiv
/** Known ancestry and descendants for one logical session. */
type SessionLineageTrace = {
  /** Detached record for the session that was traced. */
  target: SessionRecord
  /** Known parents from the immediate parent outward. */
  ancestors: SessionRecord[]
  /** Complete known descendant trees rooted at the target's direct children. */
  descendants: SessionLineageNode[]
} & (
  | {
    /** The complete parent chain is present in the logical corpus. */
    complete: true
    /** Detached record at the top of the complete lineage. */
    root: SessionRecord
  }
  | {
    /** The parent chain leaves the visible logical corpus. */
    complete: false
    /** First parent id that is not present in the logical corpus. */
    unresolvedParentId: SessionId
  }
)
```

## 有界事件读取

请求指定一个原始 seq 及可选的邻近数量。结果携带 `SessionHeader` 而非可用性标志，使已知的实时目标可以独立于持久化健康状态。

```ts type-equiv
/** Request for one event plus raw neighboring log context. */
interface SessionEventReadRequest {
  /** Session that owns the target event. */
  sessionId: SessionId
  /** Target event seq. */
  seq: number
  /** Number of preceding raw events to include. */
  before?: number
  /** Number of following raw events to include. */
  after?: number
}
```

```ts type-equiv
/** Full target event and a bounded raw-log window. */
interface SessionEventWindow {
  /** Cloned header for the live-preferred source read. */
  session: SessionHeader
  /** Full cloned target event. */
  target: SessionEvent
  /** Full cloned events from `startSeq` through `endSeq`. */
  events: SessionEvent[]
  /** First seq included in `events`. */
  startSeq: number
  /** Last seq included in `events`. */
  endSeq: number
}
```

## 事件关系

事件追踪会区分位置性的 surface 替换与已记录 provenance。除 `replacementChain` 外，每个 seq 列表都包含直接链接；该链从目标沿直接 replacer 追踪到最终的位置替换。

```ts type-equiv
/** Request for direct surface and provenance relationships around one event. */
interface SessionEventTraceRequest {
  /** Session that owns the target event. */
  sessionId: SessionId
  /** Target event seq. */
  seq: number
}
```

```ts type-equiv
/** Direct surface and provenance relationships for one event. */
interface SessionEventTrace {
  /** Lightweight target record. */
  target: SessionEventRecord
  /** Immediate positional replacement event, when the target was shadowed. */
  replacedBy?: number
  /** Positional replacers from the immediate replacement to the final replacement. */
  replacementChain: number[]
  /** Surface nodes directly removed when the target itself performed a replacement. */
  replacedEventSeqs: number[]
  /** Direct logged provenance sources in their recorded order. */
  sourceEventSeqs: number[]
  /** Later events that directly name the target as a provenance source, in log order. */
  derivedEventSeqs: number[]
}
```

```ts type-equiv
/** Event relationships bound to the same session-header observation. */
interface SessionEventTraceObservation extends SessionEventTrace {
  /** Cloned header selected with the event log used for the trace. */
  session: SessionHeader
}
```

## 错误

封闭的 code 联合类型区分请求校验、目标缺失、surface 日志格式错误、可选后端故障与矛盾的源元数据。

```ts type-equiv
/** Stable machine-routable failure taxonomy for session reads, traces, and search. */
type SessionQueryErrorCode =
  | 'SESSION_QUERY_ABORTED'
  | 'SESSION_QUERY_EVENT_NOT_FOUND'
  | 'SESSION_QUERY_INDEX_FAILED'
  | 'SESSION_QUERY_INVALID_CONFIG'
  | 'SESSION_QUERY_INVALID_CURSOR'
  | 'SESSION_QUERY_INVALID_FILTER'
  | 'SESSION_QUERY_INVALID_LIMIT'
  | 'SESSION_QUERY_INVALID_QUERY'
  | 'SESSION_QUERY_INVALID_LINEAGE'
  | 'SESSION_QUERY_INVALID_SURFACE'
  | 'SESSION_QUERY_INVALID_WINDOW'
  | 'SESSION_QUERY_PERSISTENCE_FAILED'
  | 'SESSION_QUERY_SESSION_NOT_FOUND'
  | 'SESSION_QUERY_STALE_CURSOR'
  | 'SESSION_QUERY_SOURCE_CONFLICT'
```
