@actyx/pond

Enumerations

• EventOrder
• EventsSortOrder
• MsgType
• NodeStatus

Classes

• NodeInfo

Interfaces

• EventFns
• SnapshotStore
• Tag
• TaggedTypedEvent
• Tags
• Where

Type aliases

Actyx

Ƭ Actyx: EventFns & { nodeId: NodeId ; snapshotStore: SnapshotStore ; dispose: () => void ; nodeInfo: (maxAgeMillis: number) => Promise<NodeInfo> ; waitForSync: () => Promise<void> }

Access all sorts of functionality related to the Actyx system!

---

ActyxEvent

Ƭ ActyxEvent<E>: Object

An event with its metadata.

Type parameters

Name	Type
E	unknown

Type declaration

Name	Type
meta	Metadata
payload	E

---

ActyxOpts

Ƭ ActyxOpts: Object

Options used when creating a new Actyx instance.

Type declaration

Name	Type	Description
actyxHost?	string	Host of the Actxy service. This defaults to localhost and should stay localhost in almost all cases.
actyxPort?	number	API port of the Actyx service. Defaults to 4454.
onConnectionEstablished?	() => void	Hook, when the connection to the store has been established.
onConnectionLost?	() => void	Hook, when the connection to the store is closed

---

ActyxTestOpts

Ƭ ActyxTestOpts: Object

Options used when creating a new TEST Actyx instance.

Type declaration

Name	Type	Description
nodeId?	NodeId	Local node id to use
timeInjector?	TimeInjector	Install the given time source for test purposes beta

---

AddEmission

Ƭ AddEmission<EWrite>: <E>(...args: [Tags<E>, E] | [TaggedTypedEvent<E>]) => void

Type parameters

Name
EWrite

Type declaration

▸ <E>(...args): void

Queue emission of an event whose type is covered by EWrite.

Type parameters

Name	Type
E	extends EWrite

Parameters

Name	Type
...args	[Tags<E>, E] | [TaggedTypedEvent<E>]

Returns

void

---

AppId

Ƭ AppId: string

An Actyx app id.

---

AppManifest

Ƭ AppManifest: Object

Manifest describing an Actyx application. Used for authorizing API access.

Type declaration

Name	Type	Description
appId	string	Structured application id. For testing and development purposes, you can always pass 'com.example.somestring' For production, you will buy a license from Actyx for your specific app id like com.my-company.my-app.
displayName	string	Arbitrary string describing the app.
signature?	string	Manifest signature, if it’s not an example app.
version	string	Arbitrary version string

---

AqlDiagnosticMessage

Ƭ AqlDiagnosticMessage: Object

AQL diagnostic output describing an error that occured during query evaluation.

beta

Type declaration

Name	Type	Description
message	string	-
severity	string	-
type	"diagnostic"	A problem occured

---

AqlEventMessage

Ƭ AqlEventMessage: Object

AQL message conveying a raw event or a record created by mapping an event via SELECT.

beta

Type declaration

Name	Type	Description
meta	Metadata	Metadata of the event that yielded this record.
payload	unknown	Payload data generated by the AQL query via SELECT statements.
type	"event"	A simply-mapped event

---

AqlFutureCompat

Ƭ AqlFutureCompat: Object

Future versions of AQL will know additional response message types.

beta

Type declaration

Name	Type	Description
meta	Record<string, unknown>	Consult AQL documentation to find out about future metadata contents.
payload	unknown	-
type	Exclude<"event" | "offsets" | "diagnostic", string>	Consult AQL documentation to find out about future available types.

---

AqlOffsetsMsg

Ƭ AqlOffsetsMsg: Object

AQL message describing the offsets at the current state of the response stream.

beta

Type declaration

Name	Type
offsets	OffsetMap
type	"offsets"

---

AqlQuery

Ƭ AqlQuery: string | { order?: EventsSortOrder ; query: string }

An aql query is either a plain string, or an object containing the string and the desired order.

beta

---

AqlResponse

Ƭ AqlResponse: AqlEventMessage | AqlOffsetsMsg | AqlDiagnosticMessage | AqlFutureCompat

Response message returned by running AQL query.

beta

---

AutoCappedQuery

Ƭ AutoCappedQuery: Object

Query for a set of events which is automatically capped at the latest available upperBound.

Type declaration

Name	Type	Description
horizon?	string	Earliest event ID to consider in the result
lowerBound?	OffsetMap	Starting point for the query. Everything up-to-and-including lowerBound will be omitted from the result. Defaults to empty map, which means no lower bound at all. Sources not listed in the lowerBound will be delivered in full.
order?	EventsSortOrder	Desired order of delivery. Defaults to 'Asc'
query?	Where<unknown>	Statement to select specific events. Defaults to allEvents.

---

Caching

Ƭ Caching: NoCaching | InProcessCaching

Caching indicator for pond.observeAll().

beta

---

CancelSubscription

Ƭ CancelSubscription: () => void

Type declaration

▸ (): void

Cancel an ongoing aggregation (the provided callback will stop being called).

Returns

void

---

Counters

Ƭ Counters: Readonly<CountersMut>

Immutable swarm counters information.

---

CountersMut

Ƭ CountersMut: Object

Mutable swarm counters information.

Type declaration

Name	Type	Description
both	number	Both the pond and the swarm have it
own	number	The pond has it, the swarm doesn't
swarm	number	The swarm has it, the pond does not

---

EarliestQuery

Ƭ EarliestQuery<E>: Object

Query for observeEarliest.

beta

Type parameters

Name
E

Type declaration

Name	Type	Description
eventOrder?	EventOrder	The order to find min/max for. Defaults to Lamport.
lowerBound?	OffsetMap	Starting point for the query. Everything up-to-and-including lowerBound will be omitted from the result. Defaults to empty map, which means no lower bound at all. Sources not listed in the lowerBound will be delivered in full.
query	Where<E>	Statement to select specific events.

---

EventChunk

Ƭ EventChunk: Object

A chunk of events, with lower and upper bound. A call to queryKnownRange with the included bounds is guaranteed to return exactly the contained set of events. A call to subscribe with the included lowerBound, however, may find new events from sources not included in the bounds.

Type declaration

Name	Type	Description
events	ActyxEvent[]	The event data. Sorting depends on the request which produced this chunk.
lowerBound	OffsetMap	The lower bound of the event chunk, independent of its sorting in memory.
upperBound	OffsetMap	The upper bound of the event chunk, independent of its sorting in memory.

---

EventKey

Ƭ EventKey: Object

Triple that Actyx events are sorted and identified by.

Type declaration

Name	Type
lamport	Lamport
offset	Offset
stream	StreamId

---

EventSubscription

Ƭ EventSubscription: Object

Subscription to a set of events that may still grow.

Type declaration

Name	Type	Description
lowerBound?	OffsetMap	Starting point for the query. Everything up-to-and-including lowerBound will be omitted from the result. Defaults to empty map, which means no lower bound at all. Sources not listed in the lowerBound will be delivered in full.
query?	Where<unknown>	Statement to select specific events. Defaults to allEvents.

---

EventsMsg

Ƭ EventsMsg<E>: Object

Implies consumer should apply the given events to its latest local state.

alpha

Type parameters

Name
E

Type declaration

Name	Type
caughtUp	boolean
events	ActyxEvent<E>[]
type	events

---

EventsOrTimetravel

Ƭ EventsOrTimetravel<E>: StateMsg | EventsMsg<E> | TimeTravelMsg<E>

Possible subscribe_monotonic message types.

alpha

Type parameters

Name
E

---

Fish

Ƭ Fish<S, E>: Object

A Fish<S, E> describes an ongoing aggregration (fold) of events of type E into state of type S. A Fish always sees events in the correct order, even though event delivery on Actyx is only eventually consistent: To this effect, arrival of an hitherto unknown event "from the past" will cause a replay of the aggregation from an earlier state, instead of passing that event to the Fish out of order.

Type parameters

Name
S
E

Type declaration

Name	Type	Description
fishId	FishId	-
initialState	S	-
isReset?	IsReset<E>	-
onEvent	Reduce<S, E>	Function to create the next state from previous state and next event. It works similar to Array.reduce. Do note however that — while it may modify the passed-in state — this function must be pure: - It should not cause any side-effects (except logging) - It should not reference dynamic outside state like random numbers or the current time. The result must depend purely on the input parameters.
where	Where<E>	Selection of events to aggregate in this Fish. You may specify plain strings inline: where: Tags('my', 'tag', 'selection') (which requires all three tags) Or refer to typed static tags: where: myFirstTag.and(mySecondTag).or(myThirdTag) In both cases you would select events which contain all three given tags.
deserializeState?	(jsonState: unknown) => S	-

---

FishErrorContext

Ƭ FishErrorContext: { event: unknown ; metadata: Metadata ; occuredIn: "onEvent" ; state: unknown } | { event: unknown ; metadata: Metadata ; occuredIn: "isReset" } | { jsonState: unknown ; occuredIn: "deserializeState" }

Context for an error thrown by a Fish’s functions.

---

FishErrorReporter

Ƭ FishErrorReporter: (err: unknown, fishId: FishId, detail: FishErrorContext) => void

Type declaration

▸ (err, fishId, detail): void

Error reporter for when Fish functions throw exceptions.

Parameters

Name	Type
err	unknown
fishId	FishId
detail	FishErrorContext

Returns

void

---

FishId

Ƭ FishId: Object

Unique identifier for a fish.

Type declaration

Name	Type
entityType	string
name	string
version	number

---

FishProcessInfo

Ƭ FishProcessInfo: Object

How many Fish are active, and of which entityTypes?

Type declaration

Name	Type
fish	Object
numBeingProcessed	number

---

FixedStart

Ƭ FixedStart: Object

Sent by the client to indicate it wants event delivery to start from this point. Implies that a state was cached in-process by the client and so it does not want to start from a snapshot known to Actyx.

alpha

Type declaration

Name	Type
from	OffsetMap
horizon?	EventKey
latestEventKey	EventKey

---

FullWaitForSwarmConfig

Ƭ FullWaitForSwarmConfig: Object

Configure how to wait for swarm.

Type declaration

Name	Type	Description
allowSkip	boolean	True if we allow the user to skip the splash screen
enabled	boolean	Splash screen enabled
minSources	number	Minimum number of sources until we consider that we got the swarm state
waitForSwarmMs	number	Delay until we consider that we got the swarm state
waitForSyncMs?	number	Delay that we allow to sync with the swarm state (leave undefined to wait indefinitely)

---

GetNodeConnectivityParams

Ƭ GetNodeConnectivityParams: Object

Parameter object for the Pond.getNodeConnectivity call.

Type declaration

Name	Type
specialSources?	NodeId[]
callback	(newState: unknown) => void

---

HasOffsetAndStream

Ƭ HasOffsetAndStream: Object

Anything with offset on a stream.

Type declaration

Name	Type
offset	number
stream	string

---

HasTags

Ƭ HasTags: Object

Anything that has tags. @alpha

Type declaration

Name	Type
tags	string[]

---

InProcessCaching

Ƭ InProcessCaching: Object

Indicate in-process (nonpersistent) Caching.

beta

Type declaration

Name	Type
key	string
type	"in-process"

---

InvalidateAllSnapshots

Ƭ InvalidateAllSnapshots: () => Promise<void>

Type declaration

▸ (): Promise<void>

The signature of the function to invalidate all stored snapshots.

beta

Returns

Promise<void>

---

InvalidateSnapshots

Ƭ InvalidateSnapshots: (semantics: string, name: string, key: EventKey) => Promise<void>

Type declaration

▸ (semantics, name, key): Promise<void>

The signature of the function to invalidate snapshots for a given fish.

beta

Parameters

Name	Type
semantics	string
name	string
key	EventKey

Returns

Promise<void>

---

IsReset

Ƭ IsReset<E>: (event: E, metadata: Metadata) => boolean

Type parameters

Name
E

Type declaration

▸ (event, metadata): boolean

A function indicating events which completely determine the state. Any event for which isReset returns true will be applied to the initial state, all earlier events discarded.

Parameters

Name	Type
event	E
metadata	Metadata

Returns

boolean

---

Lamport

Ƭ Lamport: number

Lamport timestamp, cf. https://en.wikipedia.org/wiki/Lamport_timestamp

---

LatestQuery

Ƭ LatestQuery<E>: EarliestQuery<E>

Query for observeLatest.

beta

Type parameters

Name
E

---

LocalSnapshot

Ƭ LocalSnapshot<S>: StateWithProvenance<S> & { cycle: number ; eventKey: EventKey ; horizon: EventKey | undefined }

A local snapshot of state.

beta

Type parameters

Name
S

---

LocalSnapshotFromIndex

Ƭ LocalSnapshotFromIndex: LocalSnapshot<string>

The format of snapshots coming back from the store.

beta

---

Metadata

Ƭ Metadata: Object

Generic Metadata attached to every event.

Type declaration

Name	Type
appId	AppId
eventId	string
isLocalEvent	boolean
lamport	Lamport
offset	Offset
stream	StreamId
tags	string[]
timestampMicros	Timestamp
timestampAsDate	() => Date

---

Milliseconds

Ƭ Milliseconds: number

Some number of milliseconds.

---

MonotonicSubscription

Ƭ MonotonicSubscription<E>: Object

Subscribe to a stream of events that will never go backwards in time, but rather terminate with a timetravel-message.

alpha

Type parameters

Name
E

Type declaration

Name	Type	Description
attemptStartFrom	FixedStart	Sending 'attemptStartFrom' means we DONT want a snapshot sent as initial message.
query	Where<E>	Statement to select specific events.
sessionId	string	User-chosen session id, used to find cached intermediate states aka local snapshots.

---

NoCaching

Ƭ NoCaching: Object

Indicator for disabled caching of pond.observeAll().

beta

Type declaration

Name	Type
type	"none"

---

NodeId

Ƭ NodeId: string

An Actyx source id.

---

NodeInfoEntry

Ƭ NodeInfoEntry: Object

All the info we got for a single node

This might grow in the future to include things like timestamps

Type declaration

Name	Type
own?	number
swarm?	number

---

ObserveAllOpts

Ƭ ObserveAllOpts: Partial<{ caching: Caching ; expireAfterFirst: Milliseconds ; expireAfterSeed: Milliseconds }>

Optional parameters to pond.observeAll

beta

---

Offset

Ƭ Offset: number

Offset within an Actyx event stream.

---

OffsetMap

Ƭ OffsetMap: Record<StreamId, Offset>

A offset map stores the high water mark for each source.

The value in the psn map is the highest psn seen for this source. Since sequence numbers start with 0, the default value for sources that are not present is -1

---

OffsetMapBuilder

Ƭ OffsetMapBuilder: Record<string, Offset>

Relatively pointless attempt to distinguish between mutable and immutable psnmap See https://github.com/Microsoft/TypeScript/issues/13347 for why this does not help much.

---

OffsetMapCompanion

Ƭ OffsetMapCompanion: Object

OffsetMap companion functions.

Type declaration

Name	Type
empty	OffsetMap
isEmpty	(m: OffsetMap) => boolean
lookup	(m: OffsetMap, s: string) => number
lookupOrUndefined	(m: OffsetMap, s: string) => undefined | number
update	(m: OffsetMapBuilder, ev: HasOffsetAndStream) => OffsetMapBuilder

---

OffsetsResponse

Ƭ OffsetsResponse: Object

Response to an offsets() call

Type declaration

Name	Type	Description
present	OffsetMap	The current local present, i.e. offsets up to which we can provide events without any gaps.
toReplicate	Record<StreamId, number>	For each stream we still need to download events from, the number of pending events.

---

OnCompleteOrErr

Ƭ OnCompleteOrErr: (err?: unknown) => void

Type declaration

▸ (err?): void

Handler for a streaming operation ending, either normally or with an error. If the err argument is defined, the operation completed due to an error. Otherwise, it completed normally.

Parameters

Name	Type
err?	unknown

Returns

void

---

PendingCommand

Ƭ PendingCommand: Object

Pending command application.

Type declaration

Name	Type
subscribe	(whenEmitted: () => void) => void
toPromise	() => Promise<void>

---

PendingEmission

Ƭ PendingEmission: Object

Allows you to register actions for when event emission has completed.

Type declaration

Name	Type
subscribe	(whenEmitted: (meta: Metadata[]) => void) => void
toPromise	() => Promise<Metadata[]>

---

Pond

Ƭ Pond: Object

Main interface for interaction with the Actyx event system. New instances are created via Pond.default() or Pond.of(options). Acquire a Pond for testing (which uses a simulated clean Event Store) via Pond.test().

Type declaration

Name	Type
currentState	<S, E>(fish: Fish<S, E>) => Promise<S>
dispose	() => void
emit	<E>(tags: Tags<E>, event: E) => PendingEmission
events	() => Actyx
getPondState	(callback: (newState: PondState) => void) => CancelSubscription
info	() => PondInfo
keepRunning	<S, EWrite>(fish: Fish<S, any>, fn: StateEffect<S, EWrite>, autoCancel?: (state: S) => boolean) => CancelSubscription
nodeInfo	(maxAgeMillis: number) => Promise<NodeInfo>
observe	<S, E>(fish: Fish<S, E>, callback: (newState: S) => void, stoppedByError?: (err: unknown) => void) => CancelSubscription
observeAll	<ESeed, S>(seedEventsSelector: Where<ESeed>, makeFish: (seedEvent: ESeed) => undefined | Fish<S, any>, opts: Partial<{ caching: Caching ; expireAfterFirst: Milliseconds ; expireAfterSeed: Milliseconds }>, callback: (states: S[]) => void) => CancelSubscription
observeOne	<ESeed, S>(seedEventSelector: Where<ESeed>, makeFish: (seedEvent: ESeed) => Fish<S, any>, callback: (newState: S) => void, stoppedByError?: (err: unknown) => void) => CancelSubscription
publish	(event: TaggedEvent) => Promise<Metadata>(events: TaggedEvent[]) => Promise<Metadata[]>
run	<S, EWrite>(fish: Fish<S, any>, fn: StateEffect<S, EWrite>) => PendingCommand
waitForSwarmSync	(params: WaitForSwarmSyncParams) => void

---

PondInfo

Ƭ PondInfo: Object

Information concerning the running Pond.

Type declaration

Name	Type
nodeId	NodeId

---

PondOptions

Ƭ PondOptions: Object

Advanced configuration options for the Pond.

Type declaration

Name	Type	Description
fishErrorReporter?	FishErrorReporter	Callback that is invoked whenever Fish execution encounters an error. If none is supplied, errors will be logged to the console.

---

PondState

Ƭ PondState: Object

What sort of activity is currently going on in the Pond?

Type declaration

Name	Type
commands	FishProcessInfo
eventsFromOtherSources	FishProcessInfo
hydration	FishProcessInfo

---

Progress

Ƭ Progress: Object

Sync progress in terms of event numbers.

Type declaration

Name	Type
current	number
max	number
min	number

---

RangeQuery

Ƭ RangeQuery: Object

Query for a fixed set of known events.

Type declaration

Name	Type	Description
horizon?	string	Earliest event ID to consider in the result
lowerBound?	OffsetMap	Starting point (exclusive) for the query. Everything up-to-and-including lowerBound will be omitted from the result. Defaults empty record. Events from sources not included in the lowerBound will be delivered from start, IF they are included in upperBound. Events from sources missing from both lowerBound and upperBound will not be delivered at all.
order?	EventsSortOrder	Desired order of delivery. Defaults to 'Asc'
query?	Where<unknown>	Statement to select specific events. Defaults to allEvents.
upperBound	OffsetMap	Ending point (inclusive) for the query. Everything covered by upperBound (inclusive) will be part of the result. If a source is not included in upperBound, its events will not be included in the result.

---

Reduce

Ƭ Reduce<S, E>: (state: S, event: E, metadata: Metadata) => S

Type parameters

Name
S
E

Type declaration

▸ (state, event, metadata): S

Combine the existing ("old") state and next event into a new state. The returned value may be something completely new, or a mutated version of the input state.

Parameters

Name	Type
state	S
event	E
metadata	Metadata

Returns

S

---

RetrieveSnapshot

Ƭ RetrieveSnapshot: (semantics: string, name: string, version: number) => Promise<LocalSnapshotFromIndex | undefined>

Type declaration

▸ (semantics, name, version): Promise<LocalSnapshotFromIndex | undefined>

The signature of the function to retrieve a snapshot.

beta

Parameters

Name	Type
semantics	string
name	string
version	number

Returns

Promise<LocalSnapshotFromIndex | undefined>

---

SerializedStateSnap

Ƭ SerializedStateSnap: LocalSnapshot<string>

A local snapshot where the state has already been serialised.

beta

---

SplashState

Ƭ SplashState: SplashStateDiscovery | SplashStateSync

Current state of swarm synchronization procedure.

---

SplashStateDiscovery

Ƭ SplashStateDiscovery: Object

Discovering swarm state.

Type declaration

Name	Type
current	SwarmSummary
mode	"discovery"
skip?	() => void

---

SplashStateSync

Ƭ SplashStateSync: Object

Synchronizing up to the discovered swarm state.

Type declaration

Name	Type
current	SwarmSummary
mode	"sync"
progress	SyncProgress
reference	SwarmSummary
skip?	() => void

---

StateEffect

Ƭ StateEffect<S, EWrite>: (state: S, enqueue: AddEmission<EWrite>, pond: Pond) => void | Promise<void>

Type parameters

Name
S
EWrite

Type declaration

▸ (state, enqueue, pond): void | Promise<void>

Enqueue event emissions based on currently known local state.

Parameters

Name	Type
state	S
enqueue	AddEmission<EWrite>
pond	Pond

Returns

void | Promise<void>

---

StateMsg

Ƭ StateMsg: Object

Implies consumer should apply the given state.

alpha

Type declaration

Name	Type
snapshot	SerializedStateSnap
type	state

---

StateWithProvenance

Ƭ StateWithProvenance<S>: Object

A state and its corresponding psn map.

beta

Type parameters

Name
S

Type declaration

Name	Type	Description
offsets	OffsetMap	Minimum psn map that allow to reconstruct the state. Only contains sources that contain events matching the filter.
state	S	-

---

StoreSnapshot

Ƭ StoreSnapshot: (semantics: string, name: string, key: EventKey, offsets: OffsetMap, horizon: EventKey | undefined, cycle: number, version: number, tag: string, serializedBlob: string) => Promise<boolean>

Type declaration

▸ (semantics, name, key, offsets, horizon, cycle, version, tag, serializedBlob): Promise<boolean>

The signature of the function to store a snapshot.

beta

Parameters

Name	Type
semantics	string
name	string
key	EventKey
offsets	OffsetMap
horizon	EventKey | undefined
cycle	number
version	number
tag	string
serializedBlob	string

Returns

Promise<boolean>

---

StreamId

Ƭ StreamId: string

An Actyx stream id.

---

SwarmInfo

Ƭ SwarmInfo: Object

All the info we got for our device in relation to the swarm

Type declaration

Name	Type
nodes	immutable.Map<string, NodeInfoEntry>

---

SwarmSummary

Ƭ SwarmSummary: Object

Summary of swarm info

Type declaration

Name	Type
events	Counters
info	SwarmInfo
sources	Counters

---

SyncProgress

Ƭ SyncProgress: Object

Sync progress per source, and overall.

Type declaration

Name	Type
events	Progress
sources	Progress

---

TaggedEvent

Ƭ TaggedEvent: Object

An event with tags attached.

Type declaration

Name	Type
event	unknown
tags	string[]

---

TestActyx

Ƭ TestActyx: TestEventFns & { nodeId: NodeId ; snapshotStore: SnapshotStore ; dispose: () => void ; waitForSync: () => Promise<void> }

An instance of Actyx that is not talking to any Actyx instance, but mocks all functionality within TypeScript. Very useful for unit-testing.

---

TestEvent

Ƭ TestEvent: Object

A raw Actyx event to be emitted by the TestEventStore, as if it really arrived from the outside.

Type declaration

Name	Type
lamport	Lamport
offset	number
payload	unknown
stream	string
tags	string[]
timestamp	Timestamp

---

TestEventFns

Ƭ TestEventFns: EventFns & { directlyPushEvents: (events: TestEvent[]) => void }

EventFns for unit-tests.

---

TestPond

Ƭ TestPond: Pond & { directlyPushEvents: (events: TestEvent[]) => void }

A Pond with extensions for testing.

---

TestPondOptions

Ƭ TestPondOptions: PondOptions & { timeInjector?: TimeInjector }

Extended options for TestPond.

---

TimeInjector

Ƭ TimeInjector: (tags: string[], events: unknown) => Timestamp

Type declaration

▸ (tags, events): Timestamp

Test tool.

beta

Parameters

Name	Type
tags	string[]
events	unknown

Returns

Timestamp

---

TimeTravelMsg

Ƭ TimeTravelMsg<E>: Object

Implies consumer should re-subscribe starting from trigger or earlier.

alpha

Type parameters

Name
E

Type declaration

Name	Type
trigger	EventKey
type	timetravel

---

Timestamp

Ƭ Timestamp: number

Timestamp (UNIX epoch), MICROseconds resolution.

---

WaitForSwarmConfig

Ƭ WaitForSwarmConfig: Partial<FullWaitForSwarmConfig>

Partially configure waiting for the swarm.

---

WaitForSwarmSyncParams

Ƭ WaitForSwarmSyncParams: WaitForSwarmConfig & { onProgress?: (newState: SplashState) => void ; onSyncComplete: () => void }

Parameter object for the Pond.waitForSwarmSync call.

Variables

Actyx

• Actyx: Object

Function for creating Actyx instances.

Type declaration

Name	Type
of	(manifest: AppManifest, opts?: ActyxOpts) => Promise<Actyx>
test	(opts?: ActyxTestOpts) => TestActyx

---

ActyxEvent

• ActyxEvent: Object

Things related to ActyxEvent.

Type declaration

Name	Type
ord	Ord<ActyxEvent<unknown>>

---

AppId

• AppId: Object

AppId associated functions.

Type declaration

Name	Type
of	(text: string) => string

---

Caching

• Caching: Object

Caching related functions

beta

Type declaration

Name	Type
inProcess	(key: string) => Caching
isEnabled	(c: undefined | Caching) => c is InProcessCaching
none	Object
none.type	"none"

---

EventKey

• EventKey: Object

Functions related to EventKey.

Type declaration

Name	Type
ord	Ord<EventKey>
zero	EventKey
format	(key: EventKey) => string

---

Fish

• Fish: Object

Fish generic generator methods.

Type declaration

Name	Type
eventsAscending	<E>(where: Where<E>, capacity: number) => Fish<E[], E>
eventsDescending	<E>(where: Where<E>, capacity: number) => Fish<E[], E>
latestEvent	<E>(where: Where<E>) => Fish<undefined | E, E>

---

FishId

• FishId: Object

FishId associated functions.

Type declaration

Name	Type
canonical	(v: FishId) => string
of	(entityType: string, name: string, version: number) => { entityType: string ; name: string ; version: number }

---

Lamport

• Lamport: Object

Type declaration

Name	Type
zero	number
of	(value: number) => number

---

Milliseconds

• Milliseconds: Object

Helper functions for making sense of and converting Milliseconds.

Type declaration

Name	Type
zero	number
fromAny	(value: number) => number
fromDate	(date: Date) => number
fromMinutes	(value: number) => number
fromSeconds	(value: number) => number
now	(now?: number) => number
of	(time: number) => number
toSeconds	(value: number) => number
toTimestamp	(value: number) => number

---

NodeId

• NodeId: Object

SourceId associated functions.

Type declaration

Name	Type
of	(text: string) => string
random	(digits?: number) => string
streamNo	(nodeId: string, num: number) => string

---

Offset

• Offset: Object

Functions related to Offsets.

Type declaration

Name	Type	Description
max	number	A value that is above any valid Offset
min	number	A value that is below any valid Offset
zero	number	-
of	(n: number) => number	-

---

OffsetMap

• OffsetMap: OffsetMapCompanion

OffsetMap companion functions.

---

Pond

• Pond: Object

Static methods for constructing Pond instances.

Type declaration

Name	Type
default	(manifest: AppManifest) => Promise<Pond>
from	(actyx: Actyx, opts: PondOptions) => Pond
of	(manifest: AppManifest, connectionOpts: ActyxOpts, opts: PondOptions) => Promise<Pond>
test	(opts?: TestPondOptions) => TestPond

---

PondState

• PondState: Object

PondState associated functions.

Type declaration

Name	Type
isBusy	(state: PondState) => boolean
isHydrating	(state: PondState) => boolean
isProcessingCommands	(state: PondState) => boolean
isProcessingEventsFromOtherSources	(state: PondState) => boolean

---

SnapshotStore

• SnapshotStore: Object

Interface to the snapshot store.

beta

Type declaration

Name	Type
noop	SnapshotStore
inMem	() => SnapshotStore

---

StreamId

• StreamId: Object

SourceId associated functions.

Type declaration

Name	Type
of	(text: string) => string
random	() => string

---

SwarmSummary

• SwarmSummary: Object

SwarmSummary associated functions.

Type declaration

Name	Type
empty	SwarmSummary
fromSwarmInfo	(info: SwarmInfo) => SwarmSummary

---

Timestamp

• Timestamp: Object

Helper functions for making sense of and converting Timestamps.

Type declaration

Name	Type
maxSafe	number
zero	number
format	(timestamp: number) => string
fromDate	(date: Date) => number
fromDays	(value: number) => number
fromMilliseconds	(value: number) => number
fromSeconds	(value: number) => number
max	(values: number[]) => number
min	(...values: number[]) => number
now	(now?: number) => number
of	(time: number) => number
toDate	(value: number) => Date
toMilliseconds	(value: number) => number
toSeconds	(value: number) => number

---

WaitForSwarmConfig

• WaitForSwarmConfig: Object

WaitForSwarmConfig associated functions.

Type declaration

Name	Type
defaults	FullWaitForSwarmConfig

---

allEvents

• allEvents: Tags<unknown>

A Where expression that selects all events.

Functions

Tag

▸ Const Tag<E>(rawTagString, extractId?): Tag<E>

Create a new tag from the given string. (Tag factory function. Call WITHOUT new, e.g. const myTag = Tag<MyType>('my-tag'))

Type parameters

Name	Type
E	unknown

Parameters

Name	Type	Description
rawTagString	string	The raw tag string
extractId?	(e: E) => string	If supplied, this function will be used to automatically call withId for events this tag is being attached to. The automatism is disabled if there is a manual withId call.

Returns

Tag<E>

---

Tags

▸ Const Tags<E>(...requiredTags): Tags<E>

Declare a set of tags. This is a generator function to be called WITHOUT new, e.g. const required = Tags('a', 'b', 'c')

Type parameters

Name	Type
E	unknown

Parameters

Name	Type
...requiredTags	string[]

Returns

Tags<E>

---

isBoolean

▸ Const isBoolean(x): x is boolean

Refinement that checks whether typeof x === 'number'

Parameters

Name	Type
x	any

Returns

x is boolean

---

isNumber

▸ Const isNumber(x): x is number

Refinement that checks whether typeof x === 'number'

Parameters

Name	Type
x	any

Returns

x is number

---

isString

▸ Const isString(x): x is string

Refinement that checks whether typeof x === 'string'

Parameters

Name	Type
x	any

Returns

x is string

---

toEventPredicate

▸ Const toEventPredicate(where): (event: HasTags) => boolean

Turn a Where into a function that can decide whether a locally emitted event matches the clause.

We can ignore the 'local' flag since it will never exclude our local events, and this method is used solely to decide whether locally emitted events are relevant.

TODO: This will be removed once we support other means of 'I got events up to X' feedback

alpha

Parameters

Name	Type
where	Where<unknown>

Returns

fn

▸ (event): boolean

Parameters

Name	Type
event	HasTags

Returns

boolean

---

unreachable

▸ Const unreachable(x?): never

Assert that from the type information, a piece of code can never be reached. If it’s still reached at runtime, this throws an Error.

Parameters

Name	Type
x?	undefined

Returns

never

---

unreachableOrElse

▸ unreachableOrElse<T>(_, t): T

Assert that from the type information, a certain statement can never be reached, while installing a default value to return in case the type information was wrong and the statement was in fact reached.

Type parameters

Name
T

Parameters

Name	Type
_	never
t	T

Returns

T