# AggregateService

Runs an aggregate against the [EventStore](https://effect-cqrs.dambox.ch/reference/api/eventstore/#eventstore): the `command`, `read-model` and `history` actions of moleculer-cqrs, as a typed service.

## Classes

### CommandIdReused

Defined in: [src/AggregateService.ts:83](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L83)

A `commandId` that already identifies another command on the aggregate. Running a command again returns the first result only for the same command: a client that reuses an id for another one gets this rather than a result it didn’t ask for.

#### Extends

* `object` & `YieldableError`<`this`>

#### Constructors

##### Constructor

> **new CommandIdReused**(…`args`): [`CommandIdReused`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#commandidreused)

Defined in: node_modules/.pnpm/effect\@4.0.6/node_modules/effect/dist/Schema.d.ts:10979

###### Parameters

###### args

…\[`props`: `object`, `options?`: `MakeOptions`]

###### Returns

[`CommandIdReused`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#commandidreused)

###### Inherited from

`Schema.TaggedError<CommandIdReused>()("CommandIdReused", { aggregateName: Schema.String, aggregateId: Schema.String, commandId: Schema.String, /** The command that ran with the id first. */ previous: Schema.String, /** The command that came with it now. */ command: Schema.String }).constructor`

#### Properties

##### aggregateId

> `readonly` **aggregateId**: `string` = `Schema.String`

Defined in: [src/AggregateService.ts:85](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L85)

###### Inherited from

`Schema.TaggedError<CommandIdReused>()("CommandIdReused", { aggregateName: Schema.String, aggregateId: Schema.String, commandId: Schema.String, /** The command that ran with the id first. */ previous: Schema.String, /** The command that came with it now. */ command: Schema.String }).aggregateId`

##### aggregateName

> `readonly` **aggregateName**: `string` = `Schema.String`

Defined in: [src/AggregateService.ts:84](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L84)

###### Inherited from

`Schema.TaggedError<CommandIdReused>()("CommandIdReused", { aggregateName: Schema.String, aggregateId: Schema.String, commandId: Schema.String, /** The command that ran with the id first. */ previous: Schema.String, /** The command that came with it now. */ command: Schema.String }).aggregateName`

##### command

> `readonly` **command**: `string` = `Schema.String`

Defined in: [src/AggregateService.ts:90](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L90)

The command that came with it now.

###### Inherited from

`Schema.TaggedError<CommandIdReused>()("CommandIdReused", { aggregateName: Schema.String, aggregateId: Schema.String, commandId: Schema.String, /** The command that ran with the id first. */ previous: Schema.String, /** The command that came with it now. */ command: Schema.String }).command`

##### commandId

> `readonly` **commandId**: `string` = `Schema.String`

Defined in: [src/AggregateService.ts:86](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L86)

###### Inherited from

`Schema.TaggedError<CommandIdReused>()("CommandIdReused", { aggregateName: Schema.String, aggregateId: Schema.String, commandId: Schema.String, /** The command that ran with the id first. */ previous: Schema.String, /** The command that came with it now. */ command: Schema.String }).commandId`

##### previous

> `readonly` **previous**: `string` = `Schema.String`

Defined in: [src/AggregateService.ts:88](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L88)

The command that ran with the id first.

###### Inherited from

`Schema.TaggedError<CommandIdReused>()("CommandIdReused", { aggregateName: Schema.String, aggregateId: Schema.String, commandId: Schema.String, /** The command that ran with the id first. */ previous: Schema.String, /** The command that came with it now. */ command: Schema.String }).previous`

***

### EventDecodeError

Defined in: [src/AggregateService.ts:57](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L57)

A stored event doesn’t match the schema of its version, or was written in a version the aggregate doesn’t declare. Old shapes are declared with `EventVersions`.

#### Extends

* `object` & `YieldableError`<`this`>

#### Constructors

##### Constructor

> **new EventDecodeError**(…`args`): [`EventDecodeError`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#eventdecodeerror)

Defined in: node_modules/.pnpm/effect\@4.0.6/node_modules/effect/dist/Schema.d.ts:10979

###### Parameters

###### args

…\[`props`: `object`, `options?`: `MakeOptions`]

###### Returns

[`EventDecodeError`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#eventdecodeerror)

###### Inherited from

`Schema.TaggedError<EventDecodeError>()("EventDecodeError", { aggregateName: Schema.String, aggregateId: Schema.String, version: Schema.Int, type: Schema.String, schemaVersion: Schema.Int, message: Schema.String }).constructor`

#### Properties

##### aggregateId

> `readonly` **aggregateId**: `string` = `Schema.String`

Defined in: [src/AggregateService.ts:59](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L59)

###### Inherited from

`Schema.TaggedError<EventDecodeError>()("EventDecodeError", { aggregateName: Schema.String, aggregateId: Schema.String, version: Schema.Int, type: Schema.String, schemaVersion: Schema.Int, message: Schema.String }).aggregateId`

##### aggregateName

> `readonly` **aggregateName**: `string` = `Schema.String`

Defined in: [src/AggregateService.ts:58](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L58)

###### Inherited from

`Schema.TaggedError<EventDecodeError>()("EventDecodeError", { aggregateName: Schema.String, aggregateId: Schema.String, version: Schema.Int, type: Schema.String, schemaVersion: Schema.Int, message: Schema.String }).aggregateName`

##### message

> **message**: `string` = `Schema.String`

Defined in: [src/AggregateService.ts:63](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L63)

###### Inherited from

`Schema.TaggedError<EventDecodeError>()("EventDecodeError", { aggregateName: Schema.String, aggregateId: Schema.String, version: Schema.Int, type: Schema.String, schemaVersion: Schema.Int, message: Schema.String }).message`

##### schemaVersion

> `readonly` **schemaVersion**: `number` = `Schema.Int`

Defined in: [src/AggregateService.ts:62](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L62)

###### Inherited from

`Schema.TaggedError<EventDecodeError>()("EventDecodeError", { aggregateName: Schema.String, aggregateId: Schema.String, version: Schema.Int, type: Schema.String, schemaVersion: Schema.Int, message: Schema.String }).schemaVersion`

##### type

> `readonly` **type**: `string` = `Schema.String`

Defined in: [src/AggregateService.ts:61](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L61)

###### Inherited from

`Schema.TaggedError<EventDecodeError>()("EventDecodeError", { aggregateName: Schema.String, aggregateId: Schema.String, version: Schema.Int, type: Schema.String, schemaVersion: Schema.Int, message: Schema.String }).type`

##### version

> `readonly` **version**: `number` = `Schema.Int`

Defined in: [src/AggregateService.ts:60](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L60)

###### Inherited from

`Schema.TaggedError<EventDecodeError>()("EventDecodeError", { aggregateName: Schema.String, aggregateId: Schema.String, version: Schema.Int, type: Schema.String, schemaVersion: Schema.Int, message: Schema.String }).version`

***

### InvalidCommand

Defined in: [src/AggregateService.ts:47](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L47)

#### Extends

* `object` & `YieldableError`<`this`>

#### Constructors

##### Constructor

> **new InvalidCommand**(…`args`): [`InvalidCommand`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#invalidcommand)

Defined in: node_modules/.pnpm/effect\@4.0.6/node_modules/effect/dist/Schema.d.ts:10979

###### Parameters

###### args

…\[`props`: `object`, `options?`: `MakeOptions`]

###### Returns

[`InvalidCommand`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#invalidcommand)

###### Inherited from

`Schema.TaggedError<InvalidCommand>()("InvalidCommand", { aggregateName: Schema.String, type: Schema.String, message: Schema.String }).constructor`

#### Properties

##### aggregateName

> `readonly` **aggregateName**: `string` = `Schema.String`

Defined in: [src/AggregateService.ts:48](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L48)

###### Inherited from

`Schema.TaggedError<InvalidCommand>()("InvalidCommand", { aggregateName: Schema.String, type: Schema.String, message: Schema.String }).aggregateName`

##### message

> **message**: `string` = `Schema.String`

Defined in: [src/AggregateService.ts:50](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L50)

###### Inherited from

`Schema.TaggedError<InvalidCommand>()("InvalidCommand", { aggregateName: Schema.String, type: Schema.String, message: Schema.String }).message`

##### type

> `readonly` **type**: `string` = `Schema.String`

Defined in: [src/AggregateService.ts:49](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L49)

###### Inherited from

`Schema.TaggedError<InvalidCommand>()("InvalidCommand", { aggregateName: Schema.String, type: Schema.String, message: Schema.String }).type`

***

### UnknownCommand

Defined in: [src/AggregateService.ts:42](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L42)

#### Extends

* `object` & `YieldableError`<`this`>

#### Constructors

##### Constructor

> **new UnknownCommand**(…`args`): [`UnknownCommand`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#unknowncommand)

Defined in: node_modules/.pnpm/effect\@4.0.6/node_modules/effect/dist/Schema.d.ts:10979

###### Parameters

###### args

…\[`props`: `object`, `options?`: `MakeOptions`]

###### Returns

[`UnknownCommand`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#unknowncommand)

###### Inherited from

`Schema.TaggedError<UnknownCommand>()("UnknownCommand", { aggregateName: Schema.String, type: Schema.String }).constructor`

#### Properties

##### aggregateName

> `readonly` **aggregateName**: `string` = `Schema.String`

Defined in: [src/AggregateService.ts:43](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L43)

###### Inherited from

`Schema.TaggedError<UnknownCommand>()("UnknownCommand", { aggregateName: Schema.String, type: Schema.String }).aggregateName`

##### type

> `readonly` **type**: `string` = `Schema.String`

Defined in: [src/AggregateService.ts:44](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L44)

###### Inherited from

`Schema.TaggedError<UnknownCommand>()("UnknownCommand", { aggregateName: Schema.String, type: Schema.String }).type`

***

### WrongExpectedVersion

Defined in: [src/AggregateService.ts:71](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L71)

The caller’s `expectedVersion` is not the aggregate’s version: someone else changed it since the caller read it. Unlike a `ConcurrencyConflict`, this is not retried, as deciding again would overwrite a change the caller hasn’t seen.

#### Extends

* `object` & `YieldableError`<`this`>

#### Constructors

##### Constructor

> **new WrongExpectedVersion**(…`args`): [`WrongExpectedVersion`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#wrongexpectedversion)

Defined in: node_modules/.pnpm/effect\@4.0.6/node_modules/effect/dist/Schema.d.ts:10979

###### Parameters

###### args

…\[`props`: `object`, `options?`: `MakeOptions`]

###### Returns

[`WrongExpectedVersion`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#wrongexpectedversion)

###### Inherited from

`Schema.TaggedError<WrongExpectedVersion>()("WrongExpectedVersion", { aggregateName: Schema.String, aggregateId: Schema.String, expectedVersion: Schema.Int, actualVersion: Schema.Int }).constructor`

#### Properties

##### actualVersion

> `readonly` **actualVersion**: `number` = `Schema.Int`

Defined in: [src/AggregateService.ts:75](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L75)

###### Inherited from

`Schema.TaggedError<WrongExpectedVersion>()("WrongExpectedVersion", { aggregateName: Schema.String, aggregateId: Schema.String, expectedVersion: Schema.Int, actualVersion: Schema.Int }).actualVersion`

##### aggregateId

> `readonly` **aggregateId**: `string` = `Schema.String`

Defined in: [src/AggregateService.ts:73](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L73)

###### Inherited from

`Schema.TaggedError<WrongExpectedVersion>()("WrongExpectedVersion", { aggregateName: Schema.String, aggregateId: Schema.String, expectedVersion: Schema.Int, actualVersion: Schema.Int }).aggregateId`

##### aggregateName

> `readonly` **aggregateName**: `string` = `Schema.String`

Defined in: [src/AggregateService.ts:72](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L72)

###### Inherited from

`Schema.TaggedError<WrongExpectedVersion>()("WrongExpectedVersion", { aggregateName: Schema.String, aggregateId: Schema.String, expectedVersion: Schema.Int, actualVersion: Schema.Int }).aggregateName`

##### expectedVersion

> `readonly` **expectedVersion**: `number` = `Schema.Int`

Defined in: [src/AggregateService.ts:74](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L74)

###### Inherited from

`Schema.TaggedError<WrongExpectedVersion>()("WrongExpectedVersion", { aggregateName: Schema.String, aggregateId: Schema.String, expectedVersion: Schema.Int, actualVersion: Schema.Int }).expectedVersion`

## Interfaces

### AggregateService

Defined in: [src/AggregateService.ts:164](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L164)

#### Type Parameters

##### A

`A` *extends* [`Any`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#any)

#### Properties

##### aggregate

> `readonly` **aggregate**: `A`

Defined in: [src/AggregateService.ts:165](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L165)

##### commands

> `readonly` **commands**: { readonly \[K in string]: (aggregateId: string, payload: Payload\<A, K>, options?: CommandOptions) => Effect\<CommandResult\<Event\<A>>, CommandError\<A, K> | CommandFailure> }

Defined in: [src/AggregateService.ts:167](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L167)

One typed function per command.

##### dispatch

> `readonly` **dispatch**: (`input`) => `Effect`<[`CommandResult`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#commandresult)<[`Event`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#event-2)<`A`>>, [`UnknownCommand`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#unknowncommand) | [`CommandFailure`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#commandfailure) | [`CommandError`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#commanderror)<`A`, [`CommandName`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#commandname-1)<`A`>>>

Defined in: [src/AggregateService.ts:179](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L179)

Runs a `{ aggregateId, type, payload }` envelope received as JSON from outside the process. It can also carry `commandId` and `expectedVersion`, see `CommandOptions`, `correlationId`, `causationId` and `metadata`.

###### Parameters

###### input

`unknown`

###### Returns

`Effect`<[`CommandResult`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#commandresult)<[`Event`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#event-2)<`A`>>, [`UnknownCommand`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#unknowncommand) | [`CommandFailure`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#commandfailure) | [`CommandError`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#commanderror)<`A`, [`CommandName`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#commandname-1)<`A`>>>

##### history

> `readonly` **history**: (`aggregateId`, `options?`) => `Effect`\<readonly [`HistoryEntry`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#historyentry)<[`Event`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#event-2)<`A`>>\[], [`ReadError`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#readerror)>

Defined in: [src/AggregateService.ts:200](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L200)

Lists the events of one aggregate, with their decoded payload when `payload` is set. Without it the events aren’t decoded. `afterVersion` and `limit` read a long stream in pages: pass the version of the last entry to get the next page.

###### Parameters

###### aggregateId

`string`

###### options?

[`HistoryOptions`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#historyoptions)

###### Returns

`Effect`\<readonly [`HistoryEntry`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#historyentry)<[`Event`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#event-2)<`A`>>\[], [`ReadError`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#readerror)>

##### ~~readModel~~

> `readonly` **readModel**: (`aggregateId`, `options?`) => `Effect`<[`State`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#state-4)<`A`>, [`ReadError`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#readerror)>

Defined in: [src/AggregateService.ts:194](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L194)

Deprecated

Use `state`. The name came from the `read-model` action of moleculer-cqrs, and reads as the read models that view models keep.

###### Parameters

###### aggregateId

`string`

###### options?

###### finishTime?

`Utc`

###### Returns

`Effect`<[`State`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#state-4)<`A`>, [`ReadError`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#readerror)>

##### state

> `readonly` **state**: (`aggregateId`, `options?`) => `Effect`<[`State`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#state-4)<`A`>, [`ReadError`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#readerror)>

Defined in: [src/AggregateService.ts:186](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L186)

Folds the aggregate’s events into its state, optionally as it was before `finishTime`. It is the state the next command is decided on, so it is never behind.

###### Parameters

###### aggregateId

`string`

###### options?

###### finishTime?

`Utc`

###### Returns

`Effect`<[`State`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#state-4)<`A`>, [`ReadError`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#readerror)>

***

### CommandOptions

Defined in: [src/AggregateService.ts:109](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L109)

What a typed command takes besides the aggregate id and the payload.

#### Properties

##### commandId?

> `readonly` `optional` **commandId?**: `string`

Defined in: [src/AggregateService.ts:115](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L115)

Identifies the command, so that running it again on the same aggregate returns the first result instead of deciding again. The payload isn’t compared, so an id belongs to one request. See [commandIdKey](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#commandidkey).

##### expectedVersion?

> `readonly` `optional` **expectedVersion?**: `number`

Defined in: [src/AggregateService.ts:117](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L117)

The version the caller based its command on. If the aggregate is at another, the command fails with `WrongExpectedVersion`.

***

### CommandResult

Defined in: [src/AggregateService.ts:132](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L132)

#### Type Parameters

##### Event

`Event`

#### Properties

##### aggregateId

> `readonly` **aggregateId**: `string`

Defined in: [src/AggregateService.ts:134](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L134)

##### aggregateName

> `readonly` **aggregateName**: `string`

Defined in: [src/AggregateService.ts:133](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L133)

##### correlationId

> `readonly` **correlationId**: `string`

Defined in: [src/AggregateService.ts:141](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L141)

Recorded on the events, see `Causation`.

##### events

> `readonly` **events**: readonly `Event`\[]

Defined in: [src/AggregateService.ts:139](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L139)

##### position

> `readonly` **position**: `number`

Defined in: [src/AggregateService.ts:138](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L138)

The store position of the last event, to pass to `ViewModels.caughtUp`.

##### version

> `readonly` **version**: `number`

Defined in: [src/AggregateService.ts:136](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L136)

The stream version after the command.

***

### HistoryEntry

Defined in: [src/AggregateService.ts:144](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L144)

#### Type Parameters

##### Event

`Event`

#### Properties

##### causationId

> `readonly` **causationId**: `string` | `null`

Defined in: [src/AggregateService.ts:149](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L149)

##### correlationId

> `readonly` **correlationId**: `string` | `null`

Defined in: [src/AggregateService.ts:148](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L148)

##### metadata

> `readonly` **metadata**: `JsonObject`

Defined in: [src/AggregateService.ts:150](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L150)

##### payload?

> `readonly` `optional` **payload?**: `Event`

Defined in: [src/AggregateService.ts:151](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L151)

##### timestamp

> `readonly` **timestamp**: `Utc`

Defined in: [src/AggregateService.ts:146](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L146)

##### type

> `readonly` **type**: `string`

Defined in: [src/AggregateService.ts:147](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L147)

##### version

> `readonly` **version**: `number`

Defined in: [src/AggregateService.ts:145](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L145)

***

### HistoryOptions

Defined in: [src/AggregateService.ts:154](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L154)

#### Properties

##### afterVersion?

> `readonly` `optional` **afterVersion?**: `number`

Defined in: [src/AggregateService.ts:159](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L159)

Lists the events after this version. Defaults to `0`, the start of the stream.

##### finishTime?

> `readonly` `optional` **finishTime?**: `Utc`

Defined in: [src/AggregateService.ts:157](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L157)

##### limit?

> `readonly` `optional` **limit?**: `number`

Defined in: [src/AggregateService.ts:161](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L161)

Lists at most this many events.

##### payload?

> `readonly` `optional` **payload?**: `boolean`

Defined in: [src/AggregateService.ts:155](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L155)

##### startTime?

> `readonly` `optional` **startTime?**: `Utc`

Defined in: [src/AggregateService.ts:156](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L156)

***

### Options

Defined in: [src/AggregateService.ts:406](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L406)

#### Properties

##### commandIdsPerStream?

> `readonly` `optional` **commandIdsPerStream?**: `number`

Defined in: [src/AggregateService.ts:415](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L415)

How many of its latest command ids each aggregate remembers, so that a command run again with one of them returns its first result. Defaults to 100.

##### maxRetries?

> `readonly` `optional` **maxRetries?**: `number`

Defined in: [src/AggregateService.ts:408](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L408)

How many times a command is re-decided after losing a race. Defaults to 5.

##### stateCacheSize?

> `readonly` `optional` **stateCacheSize?**: `number`

Defined in: [src/AggregateService.ts:410](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L410)

How many aggregates keep their state in memory between commands. Defaults to 10,000.

***

### SnapshotOptions

Defined in: [src/AggregateService.ts:393](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L393)

Saves the state of each aggregate every so often, so a cold start replays only what came after.

#### Type Parameters

##### State

`State`

#### Properties

##### every

> `readonly` **every**: `number`

Defined in: [src/AggregateService.ts:395](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L395)

How many events to fold after a snapshot before saving the next one.

##### schema

> `readonly` **schema**: `Codec`<`State`, `any`, `never`, `never`>

Defined in: [src/AggregateService.ts:397](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L397)

How the state is stored. It is encoded as JSON.

##### version?

> `readonly` `optional` **version?**: `string` | `number`

Defined in: [src/AggregateService.ts:403](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L403)

Part of every key. Change it whenever the state or the projection changes, so that snapshots of the old state are ignored and rebuilt from the log. Defaults to `1`.

## Type Aliases

### CommandFailure

> **CommandFailure** = [`ConcurrencyConflict`](https://effect-cqrs.dambox.ch/reference/api/eventstore/#concurrencyconflict) | [`InvalidCommand`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#invalidcommand) | [`WrongExpectedVersion`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#wrongexpectedversion) | [`ReadError`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#readerror) | [`SubjectForgotten`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#subjectforgotten) | [`CommandIdReused`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#commandidreused)

Defined in: [src/AggregateService.ts:100](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L100)

How a command can fail, on top of the errors its own handler declares. `SubjectForgotten` means an event would record personal data of a forgotten subject.

***

### ReadError

> **ReadError** = [`EventStoreError`](https://effect-cqrs.dambox.ch/reference/api/eventstore/#eventstoreerror) | [`EventDecodeError`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#eventdecodeerror) | [`PersonalDataError`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#personaldataerror)

Defined in: [src/AggregateService.ts:94](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L94)

How reading events can fail. `PersonalDataError` comes from aggregates with personal fields, see `PersonalData`.

## Variables

### commandIdKey

> `const` **commandIdKey**: `"cqrs.commandId"` = `"cqrs.commandId"`

Defined in: [src/AggregateService.ts:124](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L124)

The metadata key that records the `commandId` on the events a command writes. It is reserved: metadata given under this key is dropped.

***

### commandTypeKey

> `const` **commandTypeKey**: `"cqrs.command"` = `"cqrs.command"`

Defined in: [src/AggregateService.ts:130](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L130)

The metadata key that records, beside the [commandIdKey](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#commandidkey), which command wrote the events. It is reserved too.

***

### make

> `const` **make**: {<`A`>(`aggregate`, `options`): `Effect`<[`AggregateService`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#aggregateservice)<`A`>, `never`, [`EventStore`](https://effect-cqrs.dambox.ch/reference/api/eventstore/#eventstore) | `KeyValueStore` | `Scope` | [`Context`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#context)<`A`>>; <`A`>(`aggregate`, `options?`): `Effect`<[`AggregateService`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#aggregateservice)<`A`>, `never`, [`EventStore`](https://effect-cqrs.dambox.ch/reference/api/eventstore/#eventstore) | [`Context`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#context)<`A`>>; }

Defined in: [src/AggregateService.ts:1187](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L1187)

Builds the service for one aggregate. With `snapshots` it saves states through a `KeyValueStore` from `effect/persistence`, which has layers for memory, files, SQL and the browser’s `localStorage`. Saves run in the background, and closing the scope waits for the ones still running.

#### Call Signature

> <`A`>(`aggregate`, `options`): `Effect`<[`AggregateService`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#aggregateservice)<`A`>, `never`, [`EventStore`](https://effect-cqrs.dambox.ch/reference/api/eventstore/#eventstore) | `KeyValueStore` | `Scope` | [`Context`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#context)<`A`>>

##### Type Parameters

###### A

`A` *extends* [`Any`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#any)

##### Parameters

###### aggregate

`A`

###### options

[`Options`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#options) & `object`

##### Returns

`Effect`<[`AggregateService`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#aggregateservice)<`A`>, `never`, [`EventStore`](https://effect-cqrs.dambox.ch/reference/api/eventstore/#eventstore) | `KeyValueStore` | `Scope` | [`Context`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#context)<`A`>>

#### Call Signature

> <`A`>(`aggregate`, `options?`): `Effect`<[`AggregateService`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#aggregateservice)<`A`>, `never`, [`EventStore`](https://effect-cqrs.dambox.ch/reference/api/eventstore/#eventstore) | [`Context`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#context)<`A`>>

##### Type Parameters

###### A

`A` *extends* [`Any`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#any)

##### Parameters

###### aggregate

`A`

###### options?

[`Options`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#options)

##### Returns

`Effect`<[`AggregateService`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#aggregateservice)<`A`>, `never`, [`EventStore`](https://effect-cqrs.dambox.ch/reference/api/eventstore/#eventstore) | [`Context`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#context)<`A`>>

***

### MetricNames

> `const` **MetricNames**: `object`

Defined in: [src/AggregateService.ts:460](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L460)

The names of the metrics every aggregate service records through Effect’s `Metric` module. Each series carries an `aggregate` attribute with the aggregate’s name. Read them with `Metric.snapshot`, or send them on with an exporter such as `OtlpMetrics` from `effect/observability`.

#### Type Declaration

##### commandDuration

> `readonly` **commandDuration**: `"cqrs_command_duration"` = `"cqrs_command_duration"`

Timer: how long a command took, including its wait for an earlier command on the same stream, by `command` and `outcome`. The outcome is `success`, the tag of the error, `defect` or `interrupted`. A payload that doesn’t decode, or a type the aggregate doesn’t know, fails before this point and isn’t recorded.

##### concurrencyConflicts

> `readonly` **concurrencyConflicts**: `"cqrs_concurrency_conflicts_total"` = `"cqrs_concurrency_conflicts_total"`

Counter: appends that lost a race with a writer in another process. Each is retried until `maxRetries` runs out.

##### eventsReplayed

> `readonly` **eventsReplayed**: `"cqrs_events_replayed"` = `"cqrs_events_replayed"`

Histogram: how many events a load read from the store on top of that state.

##### snapshotReadFailures

> `readonly` **snapshotReadFailures**: `"cqrs_snapshot_read_failures_total"` = `"cqrs_snapshot_read_failures_total"`

Counter: snapshots that couldn’t be read, so the stream was replayed instead.

##### snapshotSaves

> `readonly` **snapshotSaves**: `"cqrs_snapshot_saves_total"` = `"cqrs_snapshot_saves_total"`

Counter: snapshots saved, by `result`: `success` or `failure`.

##### stateCacheEvictions

> `readonly` **stateCacheEvictions**: `"cqrs_state_cache_evictions_total"` = `"cqrs_state_cache_evictions_total"`

Counter: states dropped from memory to make room for others, see `stateCacheSize`.

##### stateCacheSize

> `readonly` **stateCacheSize**: `"cqrs_state_cache_size"` = `"cqrs_state_cache_size"`

Gauge: how many states are remembered in memory.

##### stateLoads

> `readonly` **stateLoads**: `"cqrs_state_loads_total"` = `"cqrs_state_loads_total"`

Counter: where loading the current state found a state to start from, by `source`: `memory`, `snapshot`, or `replay` when it starts from the first event.

## Functions

### makeEventDecoder()

> **makeEventDecoder**<`A`>(`aggregate`, `keys?`): (`stored`) => `Effect`<[`Event`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#event-2)<`A`>, [`EventDecodeError`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#eventdecodeerror) | [`PersonalDataError`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#personaldataerror)>

Defined in: [src/AggregateService.ts:328](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L328)

Decodes a stored event with the schema of the aggregate it belongs to. An event stored in an older version is upcast to the current one on the way. An aggregate with personal fields needs `keys` to decrypt them, see `PersonalData`.

#### Type Parameters

##### A

`A` *extends* [`Any`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#any)

#### Parameters

##### aggregate

`A`

##### keys?

###### cipher

[`Cipher`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#cipher)

What encrypts and decrypts with the keys.

###### decryptionKey

(`subject`, `keyId`) => `Effect`<`Option`<[`CipherKey`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#cipherkey)>, [`PersonalDataError`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#personaldataerror)>

The key to decrypt with, `None` when the subject was forgotten. A subject without any key fails: losing the key store must not pass for forgetting.

###### encryptionKey

(`subject`) => `Effect`<[`DataKey`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#datakey), [`PersonalDataError`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#personaldataerror) | [`SubjectForgotten`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#subjectforgotten)>

The key to encrypt with, created when the subject has none. Fails for a forgotten subject.

###### forget

(`subject`) => `Effect`<`void`, [`PersonalDataError`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#personaldataerror)>

Destroys the key of a subject. Prefer [forget](https://effect-cqrs.dambox.ch/reference/api/personaldata/#forget-1), which also records it in the log.

###### isForgotten

(`subject`) => `Effect`<`boolean`, [`PersonalDataError`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#personaldataerror)>

###### rewrap

(`options?`) => `Effect`<[`RewrapResult`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#rewrapresult), [`PersonalDataError`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#personaldataerror)>

See [rewrap](https://effect-cqrs.dambox.ch/reference/api/personaldata/#rewrap).

#### Returns

(`stored`) => `Effect`<[`Event`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#event-2)<`A`>, [`EventDecodeError`](https://effect-cqrs.dambox.ch/reference/api/aggregateservice/#eventdecodeerror) | [`PersonalDataError`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#personaldataerror)>

***

### makeEventEncoder()

> **makeEventEncoder**<`A`>(`aggregate`, `keys?`): (`event`, `aggregateId?`) => `Effect`<[`NewEvent`](https://effect-cqrs.dambox.ch/reference/api/eventstore/#newevent), [`PersonalDataError`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#personaldataerror) | [`SubjectForgotten`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#subjectforgotten)>

Defined in: [src/AggregateService.ts:383](https://github.com/davidnussio/effect-cqrs/blob/9d66af7141782f3f89655e6868abe3f141c97632/src/AggregateService.ts#L383)

Encodes events into the JSON form the store keeps, in the current version of their schema. An aggregate with personal fields needs `keys` to encrypt them, and the id of the stream the event goes to, the default subject.

#### Type Parameters

##### A

`A` *extends* [`Any`](https://effect-cqrs.dambox.ch/reference/api/aggregate/#any)

#### Parameters

##### aggregate

`A`

##### keys?

###### cipher

[`Cipher`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#cipher)

What encrypts and decrypts with the keys.

###### decryptionKey

(`subject`, `keyId`) => `Effect`<`Option`<[`CipherKey`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#cipherkey)>, [`PersonalDataError`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#personaldataerror)>

The key to decrypt with, `None` when the subject was forgotten. A subject without any key fails: losing the key store must not pass for forgetting.

###### encryptionKey

(`subject`) => `Effect`<[`DataKey`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#datakey), [`PersonalDataError`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#personaldataerror) | [`SubjectForgotten`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#subjectforgotten)>

The key to encrypt with, created when the subject has none. Fails for a forgotten subject.

###### forget

(`subject`) => `Effect`<`void`, [`PersonalDataError`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#personaldataerror)>

Destroys the key of a subject. Prefer [forget](https://effect-cqrs.dambox.ch/reference/api/personaldata/#forget-1), which also records it in the log.

###### isForgotten

(`subject`) => `Effect`<`boolean`, [`PersonalDataError`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#personaldataerror)>

###### rewrap

(`options?`) => `Effect`<[`RewrapResult`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#rewrapresult), [`PersonalDataError`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#personaldataerror)>

See [rewrap](https://effect-cqrs.dambox.ch/reference/api/personaldata/#rewrap).

#### Returns

(`event`, `aggregateId?`) => `Effect`<[`NewEvent`](https://effect-cqrs.dambox.ch/reference/api/eventstore/#newevent), [`PersonalDataError`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#personaldataerror) | [`SubjectForgotten`](https://effect-cqrs.dambox.ch/reference/api/personaldata/#subjectforgotten)>