private async Task DoCrawling(
Crawling crawling,
ICrawlingRepository repository,
CancellationToken stoppingToken)
{
try
{
crawling.Status = CrawlingStatus.InProgress;
await repository.UpdateCrawlingAsync(crawling);
var options = new CrawlingOptions(crawling.Expression, crawling.Url);
var crawlingResult = await _crawlingService.CrawlAsync(options, stoppingToken);
crawling.CrawlingDetails = _mapper.MapDetails(crawling.Id, crawlingResult);
crawling.Status = CrawlingStatus.Completed;
await repository.UpdateCrawlingAsync(crawling);
}
catch (Exception e)
{
crawling.Status = CrawlingStatus.Failed;
crawling.StatusText = e.ToString();
await repository.UpdateCrawlingAsync(crawling);
_logger.LogError(e, $"Error while crawling {crawling?.Url} in background service.");
}
}
public void Ctor_ExpressionAndUrlAreValid_SuccessfullySetAllTheProperties()
{
var options = new CrawlingOptions("expression", "http://url.com/testpage.html");
options.Expression.Should().Be("expression");
options.BaseUri.ToString().Should().Be("http://url.com/testpage.html");
options.DomainUri.ToString().Should().Be("http://url.com/");
}
public void Ctor_UrlContainsQueryParameters_SetRawBaseUrlWithoutParametersValueWithoutQueryParameters(
string url,
string exoectedResult)
{
var options = new CrawlingOptions("expression", url);
options.BaseUrlWithoutParameters.Should().Be(exoectedResult);
}
public async Task <Dictionary <string, int> > CrawlAsync(CrawlingOptions options, CancellationToken cancellationToken)
{
if (options == null)
{
throw new ArgumentNullException(nameof(options), "Options cannot be null.");
}
try
{
var processedUrls = new Dictionary <string, int>();
var urlsToProcess = new Queue <string>();
urlsToProcess.Enqueue(options.BaseUri.ToString());
while (urlsToProcess.Count > 0)
{
var url = urlsToProcess.Dequeue();
if (processedUrls.ContainsKey(url))
{
continue;
}
var pageContent = await _pageLoaderService.LoadPageContentAsync(url);
var count = _scrapingService.CountOccurrence(options.Expression, pageContent);
processedUrls.Add(url, count);
var hrefs = _scrapingService.GetRelativeHrefs(pageContent);
foreach (var href in hrefs)
{
var absoluteUri = new Uri(options.DomainUri, href).ToString();
var isSubPage = options.BaseUrlWithoutParameters.IsSubPage(absoluteUri);
if (isSubPage)
{
urlsToProcess.Enqueue(absoluteUri);
}
}
cancellationToken.ThrowIfCancellationRequested();
}
return(processedUrls);
}
catch (Exception e)
{
_logger.LogError(e, "Error while crawling.");
throw;
}
}
public async Task <Dictionary <string, int> > CrawlAsync(CrawlingOptions options, CancellationToken cancellationToken)
{
if (options == null)
{
throw new ArgumentNullException(nameof(options), "Options cannot be null.");
}
try
{
return(await CrawlRecursive(options, cancellationToken));
}
catch (Exception e)
{
_logger.LogError(e, "Error while crawling.");
throw;
}
}
private async Task <Dictionary <string, int> > CrawlRecursive(
CrawlingOptions crawlOptions,
CancellationToken cancellationToken,
string url = null,
Dictionary <string, int> processedUrls = null)
{
cancellationToken.ThrowIfCancellationRequested();
if (string.IsNullOrWhiteSpace(url))
{
url = crawlOptions.BaseUri.ToString();
}
if (processedUrls == null)
{
processedUrls = new Dictionary <string, int>();
}
var pageContent = await _pageLoaderService.LoadPageContentAsync(url);
var count = _scrapingService.CountOccurrence(crawlOptions.Expression, pageContent);
processedUrls.Add(url, count);
var hrefs = _scrapingService.GetRelativeHrefs(pageContent);
foreach (var href in hrefs)
{
var absoluteUri = new Uri(crawlOptions.DomainUri, href).ToString();
var isSubPage = crawlOptions.BaseUrlWithoutParameters.IsSubPage(absoluteUri);
if (isSubPage && !processedUrls.ContainsKey(absoluteUri))
{
await CrawlRecursive(crawlOptions, cancellationToken, absoluteUri, processedUrls);
}
}
return(processedUrls);
}
public async Task CrawlAsync_ValidOptionsPassed_PerformsCrawling()
{
// Arrange
var expectedResult = new Dictionary <string, int>
{
{ "http://rooturl.com/index", 1 },
{ "http://rooturl.com/index/home", 0 },
{ "http://rooturl.com/index/home/subhome", 2 }
};
var expression = "hello world!";
var options = new CrawlingOptions(expression, "http://rooturl.com/index");
// First set of Mocked data
_pageLoaderServiceMock
.Setup(x => x.LoadPageContentAsync("http://rooturl.com/index"))
.Returns(Task.FromResult("root html"));
_scrapingServiceMock
.Setup(x => x.CountOccurrence(expression, "root html"))
.Returns(1);
_scrapingServiceMock
.Setup(x => x.GetRelativeHrefs("root html"))
.Returns(new[] { "/index/home", "/about" });
// Second set of Mocked data
_pageLoaderServiceMock
.Setup(x => x.LoadPageContentAsync("http://rooturl.com/index/home"))
.Returns(Task.FromResult("home html"));
_scrapingServiceMock
.Setup(x => x.CountOccurrence(expression, "home html"))
.Returns(0);
_scrapingServiceMock
.Setup(x => x.GetRelativeHrefs("home html"))
.Returns(new[] { "index/home/subhome" });
// Third set of Mocked data
_pageLoaderServiceMock
.Setup(x => x.LoadPageContentAsync("http://rooturl.com/index/home/subhome"))
.Returns(Task.FromResult("subhome html"));
_scrapingServiceMock
.Setup(x => x.CountOccurrence(expression, "subhome html"))
.Returns(2);
_scrapingServiceMock
.Setup(x => x.GetRelativeHrefs("subhome html"))
.Returns(new[] { "/home" });
// Act
var actualResult = await _sut.CrawlAsync(options, CancellationToken.None);
// Assert
actualResult.Should().BeEquivalentTo(expectedResult);
}
public void Ctor_ExpressionIsPassed_TrimsExpression()
{
var options = new CrawlingOptions(" some test expression ", "http://www.someurl.com");
options.Expression.Should().Be("some test expression");
}