/// <summary>
/// Begins a synchronous crawl using the uri param, subscribe to events to process data as it becomes available
/// </summary>
public virtual CrawlResult Crawl(Uri uri, CancellationTokenSource cancellationTokenSource)
{
if (uri == null)
{
throw new ArgumentNullException("uri");
}
_crawlContext.RootUri = uri;
if (cancellationTokenSource != null)
{
_crawlContext.CancellationTokenSource = cancellationTokenSource;
}
_crawlResult = new CrawlResult();
_crawlResult.RootUri = _crawlContext.RootUri;
_crawlResult.CrawlContext = _crawlContext;
_crawlComplete = false;
_logger.InfoFormat("About to crawl site [{0}]", uri.AbsoluteUri);
PrintConfigValues(_crawlContext.CrawlConfiguration);
if (_memoryManager != null)
{
_crawlContext.MemoryUsageBeforeCrawlInMb = _memoryManager.GetCurrentUsageInMb();
_logger.InfoFormat("Starting memory usage for site [{0}] is [{1}mb]", uri.AbsoluteUri, _crawlContext.MemoryUsageBeforeCrawlInMb);
}
_crawlContext.CrawlStartDate = DateTime.Now;
Stopwatch timer = Stopwatch.StartNew();
if (_crawlContext.CrawlConfiguration.CrawlTimeoutSeconds > 0)
{
_timeoutTimer = new Timer(_crawlContext.CrawlConfiguration.CrawlTimeoutSeconds * 1000);
_timeoutTimer.Elapsed += HandleCrawlTimeout;
_timeoutTimer.Start();
}
try
{
PageToCrawl rootPage = new PageToCrawl(uri)
{
ParentUri = uri, IsInternal = true, IsRoot = true
};
if (ShouldSchedulePageLink(rootPage))
{
_scheduler.Add(rootPage);
}
VerifyRequiredAvailableMemory();
CrawlSite();
}
catch (Exception e)
{
_crawlResult.ErrorException = e;
_logger.FatalFormat("An error occurred while crawling site [{0}]", uri);
_logger.Fatal(e);
}
finally
{
if (_threadManager != null)
{
_threadManager.Dispose();
}
}
if (_timeoutTimer != null)
{
_timeoutTimer.Stop();
}
timer.Stop();
if (_memoryManager != null)
{
_crawlContext.MemoryUsageAfterCrawlInMb = _memoryManager.GetCurrentUsageInMb();
_logger.InfoFormat("Ending memory usage for site [{0}] is [{1}mb]", uri.AbsoluteUri, _crawlContext.MemoryUsageAfterCrawlInMb);
}
_crawlResult.Elapsed = timer.Elapsed;
_logger.InfoFormat("Crawl complete for site [{0}]: Crawled [{1}] pages in [{2}]", _crawlResult.RootUri.AbsoluteUri, _crawlResult.CrawlContext.CrawledCount, _crawlResult.Elapsed);
return(_crawlResult);
}
/// <summary>
/// Begins a synchronous crawl using the uri param, subscribe to events to process data as it becomes available
/// </summary>
public virtual async Task <CrawlResult> CrawlAsync(Uri uri, CancellationTokenSource cancellationTokenSource)
{
if (uri == null)
{
throw new ArgumentNullException(nameof(uri));
}
_crawlContext.RootUri = _crawlContext.OriginalRootUri = uri;
if (cancellationTokenSource != null)
{
_crawlContext.CancellationTokenSource = cancellationTokenSource;
}
_crawlResult = new CrawlResult();
_crawlResult.RootUri = _crawlContext.RootUri;
_crawlResult.CrawlContext = _crawlContext;
_crawlComplete = false;
_logger.LogInformation($"About to crawl site [{uri.AbsoluteUri}]");
PrintConfigValues(_crawlContext.CrawlConfiguration);
if (_memoryManager != null)
{
_crawlContext.MemoryUsageBeforeCrawlInMb = _memoryManager.GetCurrentUsageInMb();
_logger.LogInformation($"Starting memory usage for site [{uri.AbsoluteUri}] is [{_crawlContext.MemoryUsageBeforeCrawlInMb}mb]");
}
_crawlContext.CrawlStartDate = DateTime.Now;
var timer = Stopwatch.StartNew();
if (_crawlContext.CrawlConfiguration.CrawlTimeoutSeconds > 0)
{
_timeoutTimer = new Timer(HandleCrawlTimeout, null, 0, _crawlContext.CrawlConfiguration.CrawlTimeoutSeconds * 1000);
}
try
{
var rootPage = new PageToCrawl(uri)
{
ParentUri = uri, IsInternal = true, IsRoot = true
};
if (ShouldSchedulePageLink(rootPage))
{
_scheduler.Add(rootPage);
}
VerifyRequiredAvailableMemory();
await CrawlSite();
}
catch (Exception e)
{
_crawlResult.ErrorException = e;
_logger.LogCritical($"An error occurred while crawling site [{uri}]", e);
}
finally
{
_threadManager?.Dispose();
}
_timeoutTimer?.Dispose();
timer.Stop();
if (_memoryManager != null)
{
_crawlContext.MemoryUsageAfterCrawlInMb = _memoryManager.GetCurrentUsageInMb();
_logger.LogInformation($"Ending memory usage for site [{uri.AbsoluteUri}] is [{_crawlContext.MemoryUsageAfterCrawlInMb}mb]");
}
_crawlResult.Elapsed = timer.Elapsed;
_logger.LogInformation($"Crawl complete for site [{_crawlResult.RootUri.AbsoluteUri}]: Crawled [{_crawlResult.CrawlContext.CrawledCount}] pages in [{_crawlResult.Elapsed}]");
return(_crawlResult);
}