Options
All
  • Public
  • Public/Protected
  • All
Menu

Class AggregationCursor<TSchema>

The AggregationCursor class is an internal class that embodies an aggregation cursor on MongoDB allowing for iteration over the results returned from the underlying query. It supports one by one document iteration, conversion to an array or can be iterated as a Node 4.X or higher stream

Type parameters

Hierarchy

Index

Constructors

Events

Properties

Accessors

Methods

Constructors

constructor

Events

Static Readonly CLOSE

CLOSE: "close" = ...

Properties

[kClosed]

[kClosed]: boolean
internal

[kDocuments]

[kDocuments]: TSchema[]
internal

Optional [kId]

[kId]: Long
internal

[kInitialized]

[kInitialized]: boolean
internal

[kKilled]

[kKilled]: boolean
internal

[kNamespace]

[kNamespace]: MongoDBNamespace
internal

[kOptions]

[kOptions]: AggregateOptions
internal

[kOptions]

[kOptions]: InternalAbstractCursorOptions
internal

[kPipeline]

[kPipeline]: Document[]
internal

Optional [kServer]

[kServer]: Server
internal

Optional [kSession]

[kSession]: ClientSession
internal

[kTopology]

[kTopology]: Topology
internal

Optional [kTransform]

[kTransform]: (doc: TSchema) => Document
internal

Type declaration

Static Readonly captureRejectionSymbol

captureRejectionSymbol: typeof captureRejectionSymbol

Static captureRejections

captureRejections: boolean

Sets or gets the default captureRejection value for all emitters.

Static defaultMaxListeners

defaultMaxListeners: number

Static Readonly errorMonitor

errorMonitor: typeof errorMonitor

This symbol shall be used to install a listener for only monitoring 'error' events. Listeners installed using this symbol are called before the regular 'error' listeners are called.

Installing a listener using this symbol does not change the behavior once an 'error' event is emitted, therefore the process will still crash if no regular 'error' listener is installed.

Accessors

closed

  • get closed(): boolean

cursorOptions

id

  • get id(): undefined | Long

killed

  • get killed(): boolean

loadBalanced

  • get loadBalanced(): boolean

namespace

pipeline

readConcern

readPreference

server

  • get server(): undefined | Server

session

topology

Methods

[asyncIterator]

  • [asyncIterator](): AsyncIterator<TSchema, void, undefined>

_getMore

_initialize

addCursorFlag

  • addCursorFlag(flag: "tailable" | "awaitData" | "noCursorTimeout" | "oplogReplay" | "exhaust" | "partial", value: boolean): AggregationCursor<TSchema>

  • Add a cursor flag to the cursor

    Parameters

    • flag: "tailable" | "awaitData" | "noCursorTimeout" | "oplogReplay" | "exhaust" | "partial"

      The flag to set, must be one of following ['tailable', 'oplogReplay', 'noCursorTimeout', 'awaitData', 'partial' -.

    • value: boolean

      The flag boolean value.

    Returns AggregationCursor<TSchema>

addListener

batchSize

bufferedCount

  • bufferedCount(): number

clone

close

emit

  • emit<EventKey>(event: symbol | EventKey, ...args: Parameters<AbstractCursorEvents[EventKey]>): boolean

eventNames

  • eventNames(): string[]

explain

forEach

  • forEach(iterator: (doc: TSchema) => boolean | void): Promise<void>
  • forEach(iterator: (doc: TSchema) => boolean | void, callback: Callback<void>): void

  • Iterates over all the documents for this cursor using the iterator, callback pattern.

    Parameters

    • iterator: (doc: TSchema) => boolean | void

      The iteration callback.

        • (doc: TSchema): boolean | void

        • Parameters

          • doc: TSchema

          Returns boolean | void

    Returns Promise<void>

  • Parameters

    • iterator: (doc: TSchema) => boolean | void
        • (doc: TSchema): boolean | void

        • Parameters

          • doc: TSchema

          Returns boolean | void

    • callback: Callback<void>

    Returns void

geoNear

getMaxListeners

  • getMaxListeners(): number

group

hasNext

  • hasNext(): Promise<boolean>
  • hasNext(callback: Callback<boolean>): void

limit

listenerCount

  • listenerCount<EventKey>(type: string | symbol | EventKey): number

listeners

lookup

map

  • Map all documents using the provided function If there is a transform set on the cursor, that will be called first and the result passed to this function's transform.

    remarks

    Note for Typescript Users: adding a transform changes the return type of the iteration of this cursor, it does not return a new instance of a cursor. This means when calling map, you should always assign the result to a new variable in order to get a correctly typed cursor variable. Take note of the following example:

    Type parameters

    • T

    Parameters

    • transform: (doc: TSchema) => T
        • (doc: TSchema): T

        • Parameters

          • doc: TSchema

          Returns T

    Returns AggregationCursor<T>

match

maxTimeMS

next

  • next(): Promise<null | TSchema>
  • next(callback: Callback<null | TSchema>): void
  • next(callback?: Callback<null | TSchema>): void | Promise<null | TSchema>

off

on

once

out

prependListener

prependOnceListener

project

  • Add a project stage to the aggregation pipeline

    remarks

    In order to strictly type this function you must provide an interface that represents the effect of your projection on the result documents.

    By default chaining a projection to your cursor changes the returned type to the generic Document type. You should specify a parameterized type to have assertions on your final results.

    example
    // Best way
const docs: AggregationCursor<{ a: number }> = cursor.project<{ a: number }>({ _id: 0, a: true });
// Flexible way
const docs: AggregationCursor<Document> = cursor.project({ _id: 0, a: true });
    remarks

    In order to strictly type this function you must provide an interface that represents the effect of your projection on the result documents.

    Note for Typescript Users: adding a transform changes the return type of the iteration of this cursor, it does not return a new instance of a cursor. This means when calling project, you should always assign the result to a new variable in order to get a correctly typed cursor variable. Take note of the following example:

    example
    const cursor: AggregationCursor<{ a: number; b: string }> = coll.aggregate([]);
const projectCursor = cursor.project<{ a: number }>({ _id: 0, a: true });
const aPropOnlyArray: {a: number}[] = await projectCursor.toArray();

// or always use chaining and save the final cursor

const cursor = coll.aggregate().project<{ a: string }>({
  _id: 0,
  a: { $convert: { input: '$a', to: 'string' }
}});

    Type parameters

    Parameters

    Returns AggregationCursor<T>

rawListeners

readBufferedDocuments

  • readBufferedDocuments(number?: number): TSchema[]

redact

removeAllListeners

  • removeAllListeners<EventKey>(event?: string | symbol | EventKey): AggregationCursor<TSchema>

removeListener

rewind

  • rewind(): void

  • Rewind this cursor to its uninitialized state. Any options that are present on the cursor will remain in effect. Iterating this cursor will cause new queries to be sent to the server, even if the resultant data has already been retrieved by this cursor.

    Returns void

setMaxListeners

skip

sort

stream

toArray

  • toArray(): Promise<TSchema[]>
  • toArray(callback: Callback<TSchema[]>): void

tryNext

  • tryNext(): Promise<null | TSchema>
  • tryNext(callback: Callback<null | TSchema>): void

unwind

withReadConcern

withReadPreference

Static getEventListener

  • getEventListener(emitter: DOMEventTarget | EventEmitter, name: string | symbol): Function[]

  • Returns a list listener for a specific emitter event name.

    Parameters

    • emitter: DOMEventTarget | EventEmitter
    • name: string | symbol

    Returns Function[]

Static listenerCount

  • listenerCount(emitter: EventEmitter, event: string | symbol): number
  • deprecated

    since v4.0.0

    Parameters

    • emitter: EventEmitter
    • event: string | symbol

    Returns number

Static on

  • on(emitter: EventEmitter, event: string, options?: StaticEventEmitterOptions): AsyncIterableIterator<any>

  • Parameters

    • emitter: EventEmitter
    • event: string
    • Optional options: StaticEventEmitterOptions

    Returns AsyncIterableIterator<any>

Static once

  • once(emitter: NodeEventTarget, event: string | symbol, options?: StaticEventEmitterOptions): Promise<any[]>
  • once(emitter: DOMEventTarget, event: string, options?: StaticEventEmitterOptions): Promise<any[]>

  • Parameters

    • emitter: NodeEventTarget
    • event: string | symbol
    • Optional options: StaticEventEmitterOptions

    Returns Promise<any[]>

  • Parameters

    • emitter: DOMEventTarget
    • event: string
    • Optional options: StaticEventEmitterOptions

    Returns Promise<any[]>

Generated using TypeDoc