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存储
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存储子系统持久保存一切不属于会话事件日志的数据(会话日志有自己的 seam——见 persistence.md)。它是一项可选能力,不属于 agent loop(智能体循环)主干,并按能力 seam 拆分:枢纽(hub)与 Service Definition(dsh-storage,ctx.storage)、Service Provider(注册为 json 的 dsh-storage-json 与注册为 sqlite 的 dsh-storage-sqlite),以及 Consumer 数据形式(dsh-storage-domain,ctx.storageDomain,也可经 ctx.storage.domain 访问)——它是后端约定的唯一 Consumer,也是其他一切所使用的类型化 API。枢纽自身不做任何 IO:后端拥有介质,数据形式拥有语义,产品包绝不直接触碰后端。设计记录:领域 KV 存储 Agent Note。
源码:packages/storage/storage/src/backend.ts · packages/storage/storage-domain/src/spec.ts · packages/storage/storage-domain/src/events.ts
枢纽:ctx.storage
Storage(签名)是汇合点,不是存储本体。ctx.storage.backend 是一张名称 → 后端的表:多个后端并排保持挂载,哪个后端服务哪个消费方由该消费方自己的配置决定(即领域层的路由表),绝不是枢纽全局的选择。register(name, backend) 返回 disposer;重复名称与查找未知名称都抛出 StorageError。dispose(资源释放)只注销名称——由拥有它的插件在注销之后自行关闭后端。每个后端插件还会发布一个仅用于生命周期的服务键(storageBackendServiceKey(name)),数据形式提供方注入它,使自身激活不会与后端注册发生竞态。
数据形式以一张可合并扩展的键 map 挂载到枢纽上:
/**
* Data forms mountable on the hub, keyed by form name. Form owners extend
* this map via declaration merging (the domain layer merges
* `domain: DomainFacility`) and mount the facility in their `apply`.
*/
interface StorageForms {}
mount(form, facility) 是一个 effect,其 disposer 负责卸载;对同一键的第二次挂载抛出 duplicate-mount。form(form) 解析已挂载的 facility,在拥有插件加载之前抛出 form-not-mounted——组合方应据此安排插件顺序,而不是静默推迟。领域层合并 domain: DomainFacility,因此 ctx.storage.domain 与 ctx.storageDomain 是同一个对象。
后端约定
/**
* One registered backend. A backend owns exactly one medium and shares its
* lifecycle across all facets; facets are optional members — a backend that
* cannot serve a data kind simply omits it, and resolution fails loud instead.
*/
interface StorageBackend {
/** Key-value operations; absent when this backend cannot serve them. */
readonly kv?: KvFacet
/**
* Drain in-flight writes across all open units and release the medium.
* Idempotent; concurrent and repeated calls resolve once teardown finishes.
* @returns resolution after the medium is released.
*/
close(): Promise<void>
}
一个后端拥有一个介质(一棵文件树的根目录、一个数据库文件),并提供可选的操作组;kv 是唯一已交付的操作组。KvFacet.open(descriptor) 打开一个具名 unit——KvUnitDescriptor 携带名称、当前格式版本、可选的兼容版本、表名清单,以及是否存在全局单例 slot——并返回提供 loadAll、putRecord、deleteRecord、deleteRecords、setGlobal 和 close 的 KvUnit。unit 名与表名必须匹配 UNIT_NAME_RE(既可安全用作文件名,也可安全用作 SQL 标识符片段);记录键在 single 布局中是不透明字符串,在 per-record 布局中则是匹配 [a-zA-Z0-9_-]+ 的路径片段。unit 不对并发写入做串行化——顺序由调用方负责——整文档与行存储调用在介质上是原子的,而逐记录批次在完成前中断时可能只应用一部分。写入完成后即已持久化;逐记录删除会在 POSIX 上同步目录变更。deleteRecords 以一次调用应用整批删除:所有列出的记录都从可读状态消失且后端接受该批后才 resolve,拒绝时通常整批未应用;无法建立或恢复批次状态的批量删除会以 unknown-state 拒绝,之后该 unit 的所有操作都以同一错误拒绝,直到 close() 释放它(关闭后的调用以 closed 拒绝)。single 布局在原子替换之后失败(目录 fsync 错误)时,新文件可能已落在介质上而调用方看到拒绝;必须关闭后端及其领域,再重新打开以检查已存状态,然后决定是否重试。single 介质上的版本不在当前版本和已声明兼容版本内时拒绝 version-mismatch;per-record 文档的版本在接受集合之外时读作不存在。无法按该 unit 解析的介质拒绝 malformed-medium。backend.ts 是逐条款的规范性约定,tests/contract.ts 中的共享一致性套件会针对每个后端检查共享条款。json 后端以原子方式为每个 unit 整文件重新发布一份人类可读文件;sqlite 后端在单个数据库中每行存储一份文档,用于频繁更新的数据。
声明领域
领域由其拥有包声明一次,形式是一个 spec 对象——它是该领域的身份、布局和记录 schema 的单一来源(schema 用 zod 编写,因此 z.infer 让消费方类型无需重复声明):
/** Static declaration of one domain: identity, version, and record layout. */
interface DomainSpec {
/** Domain name; must match `UNIT_NAME_RE` (doubles as the backend unit name). */
readonly name: string
/** Current domain format version; reads enforce it according to the selected layout. */
readonly version: number
/**
* Document layout for the backend unit: `single` (the default) stores the
* whole unit as one document; `per-record` stores each record as its own
* document, for units whose records are large, sparse, or individually
* disposable — the projection cache — with per-record version checks.
* Row stores retain unit-wide versioning for either layout request.
*/
readonly layout?: 'single' | 'per-record'
/**
* Older domain versions whose stored records the current record schemas
* also accept (the declaring owner vouches for that, typically by
* declaring the fields older records lack as optional). Ordinary reads admit
* listed versions without restamping saved data; writes stamp {@link version}
* while leaving untouched records as saved. Current schemas must therefore
* accept mixed generations even under the current unit stamp.
*/
readonly compatibleVersions?: readonly number[]
/**
* What `open` does with a stored table record that fails its zod schema.
* Absent (the default), the whole open rejects with `invalid-record` —
* right for authoritative data. `'backup-and-skip'` is for domains whose
* records are disposable derived data: the backend moves the record's
* document aside (`KvUnit.backupRecord`), the failure is logged with
* its cause, and the open continues with the record absent. A backend
* without `backupRecord` (no per-record document to move) falls back
* to the rejecting default. The global slot always rejects.
*/
readonly invalidRecords?: 'backup-and-skip'
/** Optional global singleton slot. */
readonly global?: DomainGlobalSpec<unknown>
/** Table declarations keyed by table name; each name must match `UNIT_NAME_RE`. */
readonly tables: Record<string, DomainTableSpec>
}
defineDomain(spec) 固定 spec 的字面量类型,并在拥有方的模块加载时、任何介质被触碰之前就明确报错:领域名或表名不匹配 UNIT_NAME_RE、版本不是非负整数、global schema 接受 null,这些都会抛出(null 是介质的「从未写入」哨兵值,可空的 global 一旦存储就无法往返还原)。domainTable<K, V>(schema) 声明一张表,其键类型是仅存在于编译期的 phantom 类型(通常是品牌化 id);descriptorOf(spec) 投影出面向后端的 unit 描述符。
领域版本
version 表示当前读写格式。compatibleVersions 列出拥有方可用当前 schema 解码其记录和全局值的旧版本;只允许小于 version 的非负整数。不声明兼容版本时,读取仍要求精确版本。接受旧版本不放宽记录校验,也不允许更新的未知版本。每行已存字段必须能无歧义地确定其含义;单元版本戳无法在混合行中区分相同字段的不同含义。
普通兼容打开和读取不会重新盖戳或规范化已存值。整单元 JSON 用一次原子文件替换发布当前版本戳和修改后的数据;SQLite 将首次单元版本更新与修改放在同一事务中提交;批量删除始终使用一个事务。删除不存在的记录或空批次不会推进版本戳。版本戳标识可接受格式,不代表值规范化已经完成;读取器必须接受混合代际。采用单元级版本戳的后端会拒绝不支持的单元版本。
发布前的序列化失败或成功的 SQLite 回滚会保留原有数据与版本戳。JSON 替换后的 I/O 失败或 SQLite 回滚本身失败时,即使操作被拒绝,已存结果也可能未知。必须停止使用并关闭后端及其领域,然后重新打开检查已存状态,再决定是否重试。各后端 README 定义了这些失败情况。
JSON 的 per-record 布局独立检查和标记每份文档;不支持的文档读取为缺失。其已有整单元引导是只读加载的例外:它将接受的历史值复制到当前版本文档中,不转换其中的值。已有的已声明表目录(即使为空)或已声明全局文档会禁止引导。SQLite 无论布局请求为何都保持单元级版本检查。布局与恢复行为见 JSON 后端和 SQLite 后端。
兼容后继版本需提升 version、在 compatibleVersions 中保留仍可读的版本戳,并扩展同一 schema 的解码和默认规则。消费者在重写选定记录时规范化值;Storage 不分配应用记录版本。验证历史版本与跨版本升级、混合值、不写入的读取、失败回滚、重启、其他单元隔离和未知版本拒绝。删表与布局变更各自需要保留及升级策略;兼容版本戳本身不定义这些策略。
v2 单元可能包含未改动的 v1 值。接受版本戳 2 的 v3 读取器仍须解码这些值;对于跳过 v2 的用户,还必须接受版本戳 1。移除旧解码逻辑前必须重写并验证全部受影响记录,包括已处于当前单元版本戳下的记录。不兼容变更需要在用新 schema 打开前执行明确且可恢复的升级;存储领域没有值迁移执行器。
如果需要回到旧读取器,必须在写入新格式前保留一致的备份:首次修改后,旧读取器可能拒绝新的版本戳。手工降低已存版本戳不会逆转值转换。领域兼容性不迁移 SQLite 物理 schema 或 JSON 外层格式,更改后端路由也不会转移已存数据。Session 格式迁移与 SQLite 物理布局版本各有拥有方,不迁移领域值。
打开的领域
/** One open domain, typed by its spec. */
interface Domain<S extends DomainSpec> {
/** Domain name from the spec. */
readonly name: string
/** Global singleton handle; a spec without `global` has no usable handle (`never`). */
readonly global: DomainGlobalHandleOf<S>
/**
* Resolve one declared table handle. Handles are stable — repeated calls
* return the same instance.
* @param name - Declared table name.
* @returns the typed table handle.
*/
table<N extends keyof S['tables'] & string>(name: N): KvTable<TableKeyOf<S, N>, TableValueOf<S, N>>
/**
* Close this domain: reject new writes immediately, drain already-queued
* writes (their events still emit), release the backend unit, then free
* the domain name for a later open. Idempotent — repeated calls share one
* teardown. The consumer owns this call (typically as its own `ctx.effect`
* disposer); the facility closes any domain left open when it unmounts.
* @returns resolution after the unit is released.
*/
close(): Promise<void>
}
读取是同步的,来自权威的内存态:KvTable 暴露 get/entries/keys/size(快照迭代器,在排队写入落地期间保持稳定),global 句柄的 get() 在第一次 set 将 slot 物化到介质之前一直返回 spec 的 initial。每次写入——put、delete、deleteMany、update、global.set——都在同一条逐领域写链上排队,先在后端完成持久化,再更新内存,最后发出 domain/changed;后端写入被拒时不会发布领域变更;持久化结果未知时必须重新打开后才能继续使用该快照;若后端报告 unknown-state,领域会被隔离,读取与后续写入都会拒绝,直到 close() 释放它。update(key, fn) 在其写链 slot 上是一次原子的读-改-写(键缺失时拒绝 missing-key);delete 一个不存在的键 resolve 为 false,不产生写入也不产生事件。deleteMany(keys) 在一个写链 slot 内把存在的键作为一次后端批量删除移除,resolve 为移除数量,并为每个被移除的键发一次 domain/changed;后端写入被拒时所有记录保持原样,也不发事件;unknown-state 拒绝会隔离整个领域。返回的记录就是存储的对象本身,不是副本——请经 put/update 整体替换,绝不要就地修改。
领域 facility:ctx.storageDomain
DomainFacility(签名)在经过路由的后端之上打开已声明的领域。路由是领域插件的配置,绝不属于枢纽:backend 指定必填的默认路由,routes 按领域名逐个覆盖。open(spec) 按严格顺序执行,每一步失败都使整个调用失败:拒绝已打开或仍在关闭中的名称(already-open),解析路由(backend-not-found),要求后端具备 kv facet(facet-unsupported),打开 unit(后端的 version-mismatch/malformed-medium 原样透传),并按 spec 的 zod schema 校验每条已存储记录和 global(invalid-record,附带出错的表与键)。调用方拥有返回的句柄,并用 Domain.close() 释放它;插件卸载时仍处于打开状态的领域由 facility 负责关闭,已关闭领域的名称只有在拆除完全结束后才释放出来供重新打开。get(name) 是无类型的诊断查找,命中的是每个类型化句柄背后包内私有的 DomainImpl 运行时;closeAll() 是卸载路径。
变更事件:domain/changed
每次持久写入都发出一个事件,严格发生在后端确认持久性之后,顺序遵循该领域的写链(事件条目):
/** Shared location fields of one durable domain change. */
interface DomainChangedBase {
/** Owning domain name. */
readonly domain: string
/** Table name; `''` for a global-singleton write. */
readonly table: string
/** Record key; `''` for a global-singleton write. */
readonly key: string
}
/** One durable domain change; a closed union — switch on `operation`. */
type DomainChanged = DomainChangedPut | DomainChangedDeleted
put(插入、覆写和 global 写入)在 value 中携带新快照——绝不携带旧值;需要做差异比较的消费方自行保留上一份快照。deleted 是不携带值的墓碑。该事件是通知,不是事务参与者:发出时提交点已经过去,因此同步抛出的监听器会被兜住并记录一条警告,而不会让已经持久的写入被拒绝;发出的值等于发出时刻的内存态。该事件仅限进程内;跨进程的变更推送是一项已记录的限制(包 README)。
Cordis API
Generated from source by scripts/gen-cordis-catalog.ts (verified fresh by pnpm run verify-cordis-catalog in doc-sync; regenerate with pnpm run gen-cordis-catalog) — the language sides differ only in locale-specific paired document paths. Signature blocks use a ts cordis-catalog fence and keep the original source JSDoc; dispatch modes are defined in the primer, and the framework-inherited ctx API lives in cordis-api/inherited.md.
ctx.storage — Storage
The storage hub service. Backends register under backend; data forms mount under their StorageForms key and are reached as ctx.storage.<form>.
/**
* Mount a data-form facility on the hub. Mounting is an effect: the
* returned disposer unmounts the form.
* @param form - Form key declared in {@link StorageForms}.
* @param facility - The facility instance to expose.
* @returns the disposer that unmounts the form.
*/
mount<K extends keyof StorageForms>(form: K, facility: StorageForms[K]): () => void
/**
* Resolve a mounted data form.
* @param form - Form key declared in {@link StorageForms}.
* @returns the mounted facility.
*/
form<K extends keyof StorageForms>(form: K): StorageForms[K]
Source: packages/storage/storage/src/index.ts
ctx.storageDomain — DomainFacility
The mounted domain facility. Opens declared domains over routed backends; one facility instance owns the open-domain table and enforces single-open per domain name.
/**
* Open one declared domain. Steps, each failing the whole call: reject a
* name that is already open (`already-open`); resolve the backend route
* (`backend-not-found` passes through from the hub); require its `kv` facet
* (`facet-unsupported`); open the unit projected from the spec (backend
* `version-mismatch`/`malformed-medium` pass through); load and validate
* every stored record against the spec's zod schemas (`invalid-record`
* with the offending table and key — unless the spec declares
* `invalidRecords: 'backup-and-skip'` and the unit can move documents aside, in
* which case the failing record is backed up, logged, and skipped);
* construct the domain.
*
* Lifecycle: the CALLER owns the returned handle and closes it via
* `Domain.close()` (typically as its own `ctx.effect` disposer) — the
* facility does not tie the domain to any consumer fiber. Domains still
* open when the facility unmounts are closed by the plugin disposer.
* @param spec - The domain declaration, typically from `defineDomain`.
* @returns the opened domain handle, typed by the spec.
*/
async open<S extends DomainSpec>(spec: S): Promise<Domain<S>>
/**
* Look up an open domain by name, untyped. Diagnostic surface; typed
* consumers hold the handle returned by {@link open}.
* @param name - Domain name.
* @returns the open domain runtime, or `undefined` when not open.
*/
get(name: string): DomainImpl | undefined
/**
* Close every domain still open on this facility. The unmount path for
* consumers that never called `Domain.close()` themselves; closing is
* idempotent, so double-closing an already-closed domain is harmless.
* @returns resolution after every unit is released.
*/
async closeAll(): Promise<void>
Source: packages/storage/storage-domain/src/index.ts
domain/* events
domain/changed — emit
A domain record or the global singleton changed, emitted once per write strictly after the backend acknowledged durability. Events of one domain arrive in its write-chain order.
/**
* A domain record or the global singleton changed, emitted once per write
* strictly after the backend acknowledged durability. Events of one
* domain arrive in its write-chain order.
* @param change - domain, table (`''` for global), key (`''` for global),
* operation discriminant, and on `put` the new snapshot.
* @mode emit
*/
'domain/changed'(change: DomainChanged): void