Earl.Crawler.Events 0.0.0-alpha.0.103

Earl Events

The "Earl Events Pattern" refers to the API that allows consumers of an IEarlCrawler to process information about the executing of a crawl.

Out-of-the-box Earl provides a collection of events that can be found adjacent to the ICrawlerEvents contract.

At the lowest level of the Crawler API, events can be handled by specifying an ICrawlerEvents implementation for the CrawlerOptions.Events provided to the IEarlCrawler. However, more commonly used, is likely the On<TEvent>(this ICrawlerOptionsBuilder builder, CrawlerEventHandler<TEvent> handler) extension method:

var options = CrawlerOptionsBuilder.CreateDefault()
    .On<CrawlUrlResultEvent>(
        async ( CrawlUrlResultEvent e, CancellationToken cancellation ) =>
        {
            // handle the event...
        }
    )
    .Build();

await crawler.CrawlAsync( new Uri(...), options );