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externalRequestQueue

Represents a queue of URLs to crawl, which is used for deep crawling of websites where you start with several URLs and then recursively follow links to other pages. The data structure supports both breadth-first and depth-first crawling orders.

Each URL is represented using an instance of the Request class. The queue can only contain unique URLs. More precisely, it can only contain Request instances with distinct uniqueKey properties. By default, uniqueKey is generated from the URL, but it can also be overridden. To add a single URL multiple times to the queue, corresponding Request objects will need to have different uniqueKey properties.

Do not instantiate this class directly, use the RequestQueue.open function instead.

RequestQueue is used by BasicCrawler, CheerioCrawler, PuppeteerCrawler and PlaywrightCrawler as a source of URLs to crawl. Unlike RequestList, RequestQueue supports dynamic adding and removing of requests. On the other hand, the queue is not optimized for operations that add or remove a large number of URLs in a batch.

RequestQueue stores its data either on local disk or in the Apify Cloud, depending on whether the APIFY_LOCAL_STORAGE_DIR or APIFY_TOKEN environment variable is set.

If the APIFY_LOCAL_STORAGE_DIR environment variable is set, the queue data is stored in that directory in an SQLite database file.

If the APIFY_TOKEN environment variable is set but APIFY_LOCAL_STORAGE_DIR is not, the data is stored in the Apify Request Queue cloud storage. Note that you can force usage of the cloud storage also by passing the forceCloud option to RequestQueue.open function, even if the APIFY_LOCAL_STORAGE_DIR variable is set.

Example usage:

// Open the default request queue associated with the crawler run
const queue = await RequestQueue.open();

// Open a named request queue
const queueWithName = await RequestQueue.open('some-name');

// Enqueue few requests
await queue.addRequest({ url: 'http://example.com/aaa' });
await queue.addRequest({ url: 'http://example.com/bbb' });
await queue.addRequest({ url: 'http://example.com/foo/bar' }, { forefront: true });

Hierarchy

  • RequestProvider
    • RequestQueue

Index

Properties

externalassumedHandledCount

assumedHandledCount: number

externalassumedTotalCount

assumedTotalCount: number

externalclient

client: RequestQueueClient

externalclientKey

clientKey: string

externalreadonlyconfig

config: Configuration

externalid

id: string

externalinternalTimeoutMillis

internalTimeoutMillis: number

externallog

log: Log

externaloptionalname

name?: string

externalrequestLockSecs

requestLockSecs: number

externaltimeoutSecs

timeoutSecs: number

Methods

externaladdRequest

  • Parameters

    Returns Promise<RequestQueueOperationInfo>

externaladdRequests

  • Parameters

    Returns Promise<BatchAddRequestsResult>

externaladdRequestsBatched

  • addRequestsBatched(...args: [requests: (string | Source)[], options?: AddRequestsBatchedOptions]): Promise<AddRequestsBatchedResult>
  • Parameters

    • externalrest...args: [requests: (string | Source)[], options?: AddRequestsBatchedOptions]

    Returns Promise<AddRequestsBatchedResult>

externaldrop

  • drop(): Promise<void>
  • Removes the queue either from the Apify Cloud storage or from the local database, depending on the mode of operation.


    Returns Promise<void>

externalfetchNextRequest

  • fetchNextRequest<T>(): Promise<null | Request<T>>
  • Returns a next request in the queue to be processed, or null if there are no more pending requests.

    Once you successfully finish processing of the request, you need to call RequestQueue.markRequestHandled to mark the request as handled in the queue. If there was some error in processing the request, call RequestQueue.reclaimRequest instead, so that the queue will give the request to some other consumer in another call to the fetchNextRequest function.

    Note that the null return value doesn’t mean the queue processing finished, it means there are currently no pending requests. To check whether all requests in queue were finished, use RequestQueue.isFinished instead.


    Type parameters

    • T: Dictionary = Dictionary

    Returns Promise<null | Request<T>>

    Returns the request object or null if there are no more pending requests.

externalgetInfo

  • getInfo(): Promise<undefined | RequestQueueInfo>
  • Returns an object containing general information about the request queue.

    The function returns the same object as the Apify API Client’s getQueue function, which in turn calls the Get request queue API endpoint.

    Example:

    {
    id: "WkzbQMuFYuamGv3YF",
    name: "my-queue",
    userId: "wRsJZtadYvn4mBZmm",
    createdAt: new Date("2015-12-12T07:34:14.202Z"),
    modifiedAt: new Date("2015-12-13T08:36:13.202Z"),
    accessedAt: new Date("2015-12-14T08:36:13.202Z"),
    totalRequestCount: 25,
    handledRequestCount: 5,
    pendingRequestCount: 20,
    }

    Returns Promise<undefined | RequestQueueInfo>

externalgetRequest

  • getRequest<T>(id: string): Promise<null | Request<T>>
  • Gets the request from the queue specified by ID.


    Type parameters

    • T: Dictionary = Dictionary

    Parameters

    • externalid: string

      ID of the request.

    Returns Promise<null | Request<T>>

    Returns the request object, or null if it was not found.

externalgetTotalCount

  • getTotalCount(): number
  • Returns an offline approximation of the total number of requests in the queue (i.e. pending + handled).

    Survives restarts and actor migrations.


    Returns number

externalhandledCount

  • handledCount(): Promise<number>
  • Returns the number of handled requests.

    This function is just a convenient shortcut for:

    const { handledRequestCount } = await queue.getInfo();

    Returns Promise<number>

externalisEmpty

  • isEmpty(): Promise<boolean>
  • Resolves to true if the next call to RequestQueue.fetchNextRequest would return null, otherwise it resolves to false. Note that even if the queue is empty, there might be some pending requests currently being processed. If you need to ensure that there is no activity in the queue, use RequestQueue.isFinished.


    Returns Promise<boolean>

externalisFinished

  • isFinished(): Promise<boolean>
  • Returns Promise<boolean>

externalmarkRequestHandled

  • markRequestHandled(...args: [request: Request<Dictionary>]): Promise<null | RequestQueueOperationInfo>
  • Parameters

    • externalrest...args: [request: Request<Dictionary>]

    Returns Promise<null | RequestQueueOperationInfo>

externalreclaimRequest

  • Parameters

    Returns Promise<null | RequestQueueOperationInfo>

staticexternalopen

  • open(...args: [queueIdOrName?: null | string, options?: StorageManagerOptions]): Promise<RequestQueue>
  • Parameters

    • externalrest...args: [queueIdOrName?: null | string, options?: StorageManagerOptions]

    Returns Promise<RequestQueue>