public Task <CrawlResult> Schedule(Website website)
{
var existing = websiteDefinitions.FirstOrDefault(x => x.Website == website);
if (existing != null)
{
return(websiteProcessingDefinitions[existing].CompletionSource.Task);
}
if (website == null || string.IsNullOrWhiteSpace(website.RootUrl))
{
var cancelledTask = new TaskCompletionSource <CrawlResult>();
cancelledTask.SetCanceled();
return(cancelledTask.Task);
}
website.RootUrl = website.RootUrl.Split('#')[0].TrimEnd('/');
WebsiteProcessingDefinition websiteProcessingDefinition;
lock (websiteLock)
{
var processingBlock = CreateProcessingBlock(website);
var websiteDefinition = new WebsiteDefinition
{
Website = website,
CrawlResult = new CrawlResult(),
};
websiteProcessingDefinition = new WebsiteProcessingDefinition(websiteDefinition)
{
ProcessingBlock = processingBlock,
CompletionSource = new TaskCompletionSource <CrawlResult>()
};
if (websiteProcessingDefinitions.TryAdd(websiteDefinition, websiteProcessingDefinition))
{
websiteDefinitions.Add(websiteDefinition);
}
}
RaiseWebsiteScheduled(website);
var outstandingLinks = Schedule(new[] { website.RootUrl });
if (outstandingLinks > 0)
{
ScheduleNext();
}
return(websiteProcessingDefinition.CompletionSource.Task);
}
public Task<CrawlResult> Schedule(Website website)
{
var existing = websiteDefinitions.FirstOrDefault(x => x.Website == website);
if (existing != null)
return websiteProcessingDefinitions[existing].CompletionSource.Task;
if (website == null || string.IsNullOrWhiteSpace(website.RootUrl))
{
var cancelledTask = new TaskCompletionSource<CrawlResult>();
cancelledTask.SetCanceled();
return cancelledTask.Task;
}
website.RootUrl = website.RootUrl.Split('#')[0].TrimEnd('/');
WebsiteProcessingDefinition websiteProcessingDefinition;
lock (websiteLock)
{
var processingBlock = CreateProcessingBlock(website);
var websiteDefinition = new WebsiteDefinition
{
Website = website,
CrawlResult = new CrawlResult(),
};
websiteProcessingDefinition = new WebsiteProcessingDefinition(websiteDefinition)
{
ProcessingBlock = processingBlock,
CompletionSource = new TaskCompletionSource<CrawlResult>()
};
if (websiteProcessingDefinitions.TryAdd(websiteDefinition, websiteProcessingDefinition))
{
websiteDefinitions.Add(websiteDefinition);
}
}
RaiseWebsiteScheduled(website);
var outstandingLinks = Schedule(new[] { website.RootUrl });
if (outstandingLinks > 0)
ScheduleNext();
return websiteProcessingDefinition.CompletionSource.Task;
}