@crawlee/http

Provides a framework for the parallel crawling of web pages using plain HTTP requests. The URLs to crawl are fed either from a static list of URLs or from a dynamic queue of URLs enabling recursive crawling of websites.

It is very fast and efficient on data bandwidth. However, if the target website requires JavaScript to display the content, you might need to use PuppeteerCrawler or PlaywrightCrawler instead, because it loads the pages using full-featured headless Chrome browser. This crawler downloads each URL using a plain HTTP request and doesn't do any HTML parsing.

The source URLs are represented using Request objects that are fed from RequestList or RequestQueue instances provided by the HttpCrawlerOptions.requestList or HttpCrawlerOptions.requestQueue constructor options, respectively.

If both HttpCrawlerOptions.requestList and HttpCrawlerOptions.requestQueue are used, the instance first processes URLs from the RequestList and automatically enqueues all of them to RequestQueue before it starts their processing. This ensures that a single URL is not crawled multiple times.

The crawler finishes when there are no more Request objects to crawl.

We can use the preNavigationHooks to adjust gotOptions:

preNavigationHooks: [
    (crawlingContext, gotOptions) => {
        // ...
    },
]

By default, HttpCrawler only processes web pages with the text/html and application/xhtml+xml MIME content types (as reported by the Content-Type HTTP header), and skips pages with other content types. If you want the crawler to process other content types, use the HttpCrawlerOptions.additionalMimeTypes constructor option. Beware that the parsing behavior differs for HTML, XML, JSON and other types of content. For more details, see HttpCrawlerOptions.requestHandler.

New requests are only dispatched when there is enough free CPU and memory available, using the functionality provided by the AutoscaledPool class. All AutoscaledPool configuration options can be passed to the autoscaledPoolOptions parameter of the HttpCrawler constructor. For user convenience, the minConcurrency and maxConcurrency AutoscaledPool options are available directly in the HttpCrawler constructor.

Example usage

import { HttpCrawler, Dataset } from '@crawlee/http';

const crawler = new HttpCrawler({
    requestList,
    async requestHandler({ request, response, body, contentType }) {
        // Save the data to dataset.
        await Dataset.pushData({
            url: request.url,
            html: body,
        });
    },
});

await crawler.run([
    'http://www.example.com/page-1',
    'http://www.example.com/page-2',
]);

Index

References

• AutoscaledPool
• AutoscaledPoolOptions
• BASIC_CRAWLER_TIMEOUT_BUFFER_SECS
• BasicCrawler
• BasicCrawlerOptions
• BasicCrawlingContext
• ClientInfo
• Configuration
• ConfigurationOptions
• Cookie
• CrawlerAddRequestsOptions
• CrawlerAddRequestsResult
• CrawlingContext
• CreateContextOptions
• CreateSession
• CriticalError
• Dataset
• DatasetConsumer
• DatasetContent
• DatasetDataOptions
• DatasetIteratorOptions
• DatasetMapper
• DatasetOptions
• DatasetReducer
• EnqueueLinksOptions
• EnqueueStrategy
• ErrorHandler
• EventManager
• EventType
• EventTypeName
• ExportOptions
• FinalStatistics
• GlobInput
• GlobObject
• IStorage
• KeyConsumer
• KeyValueStore
• KeyValueStoreIteratorOptions
• KeyValueStoreOptions
• LocalEventManager
• Log
• LogLevel
• Logger
• LoggerJson
• LoggerOptions
• LoggerText
• NonRetryableError
• ProxyConfiguration
• ProxyConfigurationFunction
• ProxyConfigurationOptions
• ProxyInfo
• PseudoUrl
• PseudoUrlInput
• PseudoUrlObject
• PushErrorMessageOptions
• QueueOperationInfo
• QueueOperationInfoOptions
• RecordOptions
• RegExpInput
• RegExpObject
• Request
• RequestHandler
• RequestList
• RequestListOptions
• RequestListSourcesFunction
• RequestListState
• RequestOptions
• RequestQueue
• RequestQueueOperationOptions
• RequestQueueOptions
• RequestTransform
• RetryRequestError
• Router
• RouterHandler
• Session
• SessionOptions
• SessionPool
• SessionPoolOptions
• SessionState
• Snapshotter
• SnapshotterOptions
• Source
• StatisticPersistedState
• StatisticState
• Statistics
• StorageClient
• StorageManagerOptions
• SystemInfo
• SystemStatus
• SystemStatusOptions
• UrlPatternObject
• UseStateOptions
• createBasicRouter
• enqueueLinks
• filterRequestsByPatterns
• log
• purgeDefaultStorages
• useState

Crawlers

• HttpCrawler

Interfaces

• HttpCrawlerOptions
• HttpCrawlingContext

Type Aliases

• HttpErrorHandler
• HttpHook
• HttpRequestHandler

Functions

• createHttpRouter

References

AutoscaledPool

Re-exports AutoscaledPool

AutoscaledPoolOptions

Re-exports AutoscaledPoolOptions

BASIC_CRAWLER_TIMEOUT_BUFFER_SECS

Re-exports BASIC_CRAWLER_TIMEOUT_BUFFER_SECS

BasicCrawler

Re-exports BasicCrawler

BasicCrawlerOptions

Re-exports BasicCrawlerOptions

BasicCrawlingContext

Re-exports BasicCrawlingContext

ClientInfo

Re-exports ClientInfo

Configuration

Re-exports Configuration

ConfigurationOptions

Re-exports ConfigurationOptions

Cookie

Re-exports Cookie

CrawlerAddRequestsOptions

Re-exports CrawlerAddRequestsOptions

CrawlerAddRequestsResult

Re-exports CrawlerAddRequestsResult

CrawlingContext

Re-exports CrawlingContext

CreateContextOptions

Re-exports CreateContextOptions

CreateSession

Re-exports CreateSession

CriticalError

Re-exports CriticalError

Dataset

Re-exports Dataset

DatasetConsumer

Re-exports DatasetConsumer

DatasetContent

Re-exports DatasetContent

DatasetDataOptions

Re-exports DatasetDataOptions

DatasetIteratorOptions

Re-exports DatasetIteratorOptions

DatasetMapper

Re-exports DatasetMapper

DatasetOptions

Re-exports DatasetOptions

DatasetReducer

Re-exports DatasetReducer

EnqueueLinksOptions

Re-exports EnqueueLinksOptions

EnqueueStrategy

Re-exports EnqueueStrategy

ErrorHandler

Re-exports ErrorHandler

EventManager

Re-exports EventManager

EventType

Re-exports EventType

EventTypeName

Re-exports EventTypeName

ExportOptions

Re-exports ExportOptions

FinalStatistics

Re-exports FinalStatistics

GlobInput

Re-exports GlobInput

GlobObject

Re-exports GlobObject

IStorage

Re-exports IStorage

KeyConsumer

Re-exports KeyConsumer

KeyValueStore

Re-exports KeyValueStore

KeyValueStoreIteratorOptions

Re-exports KeyValueStoreIteratorOptions

KeyValueStoreOptions

Re-exports KeyValueStoreOptions

LocalEventManager

Re-exports LocalEventManager

Log

Re-exports Log

LogLevel

Re-exports LogLevel

Logger

Re-exports Logger

LoggerJson

Re-exports LoggerJson

LoggerOptions

Re-exports LoggerOptions

LoggerText

Re-exports LoggerText

NonRetryableError

Re-exports NonRetryableError

ProxyConfiguration

Re-exports ProxyConfiguration

ProxyConfigurationFunction

Re-exports ProxyConfigurationFunction

ProxyConfigurationOptions

Re-exports ProxyConfigurationOptions

ProxyInfo

Re-exports ProxyInfo

PseudoUrl

Re-exports PseudoUrl

PseudoUrlInput

Re-exports PseudoUrlInput

PseudoUrlObject

Re-exports PseudoUrlObject

PushErrorMessageOptions

Re-exports PushErrorMessageOptions

QueueOperationInfo

Re-exports QueueOperationInfo

QueueOperationInfoOptions

Re-exports QueueOperationInfoOptions

RecordOptions

Re-exports RecordOptions

RegExpInput

Re-exports RegExpInput

RegExpObject

Re-exports RegExpObject

Request

Re-exports Request

RequestHandler

Re-exports RequestHandler

RequestList

Re-exports RequestList

RequestListOptions

Re-exports RequestListOptions

RequestListSourcesFunction

Re-exports RequestListSourcesFunction

RequestListState

Re-exports RequestListState

RequestOptions

Re-exports RequestOptions

RequestQueue

Re-exports RequestQueue

RequestQueueOperationOptions

Re-exports RequestQueueOperationOptions

RequestQueueOptions

Re-exports RequestQueueOptions

RequestTransform

Re-exports RequestTransform

RetryRequestError

Re-exports RetryRequestError

Router

Re-exports Router

RouterHandler

Re-exports RouterHandler

Session

Re-exports Session

SessionOptions

Re-exports SessionOptions

SessionPool

Re-exports SessionPool

SessionPoolOptions

Re-exports SessionPoolOptions

SessionState

Re-exports SessionState

Snapshotter

Re-exports Snapshotter

SnapshotterOptions

Re-exports SnapshotterOptions

Source

Re-exports Source

StatisticPersistedState

Re-exports StatisticPersistedState

StatisticState

Re-exports StatisticState

Statistics

Re-exports Statistics

StorageClient

Re-exports StorageClient

StorageManagerOptions

Re-exports StorageManagerOptions

SystemInfo

Re-exports SystemInfo

SystemStatus

Re-exports SystemStatus

SystemStatusOptions

Re-exports SystemStatusOptions

UrlPatternObject

Re-exports UrlPatternObject

UseStateOptions

Re-exports UseStateOptions

createBasicRouter

Re-exports createBasicRouter

enqueueLinks

Re-exports enqueueLinks

filterRequestsByPatterns

Re-exports filterRequestsByPatterns

log

Re-exports log

purgeDefaultStorages

Re-exports purgeDefaultStorages

useState

Re-exports useState

Type Aliases

HttpErrorHandler

HttpErrorHandler<UserData, JSONData>: ErrorHandler<HttpCrawlingContext<UserData, JSONData>>

Type parameters

• UserData: Dictionary = any
• JSONData: JsonValue = any

HttpHook

HttpHook<UserData, JSONData>: InternalHttpHook<HttpCrawlingContext<UserData, JSONData>>

Type parameters

• UserData: Dictionary = any
• JSONData: JsonValue = any

HttpRequestHandler

HttpRequestHandler<UserData, JSONData>: RequestHandler<HttpCrawlingContext<UserData, JSONData>>

Type parameters

• UserData: Dictionary = any
• JSONData: JsonValue = any