public static async Task <CrawlResponse> DownloadHtml(Uri uri, string userAgent, CrawlRequest reqBody)
{
var request = (HttpWebRequest)WebRequest.Create(uri);
request.Method = "GET";
request.UserAgent = userAgent;
if (!string.IsNullOrEmpty(reqBody.ETag))
{
request.Headers.Add(HttpRequestHeader.IfNoneMatch, reqBody.ETag);
}
using (var response = (HttpWebResponse)await request.GetResponseAsync())
{
using (var stream = response.GetResponseStream())
using (var reader = new StreamReader(stream))
{
// TODO: look for schema.org
var html = await reader.ReadToEndAsync();
// TODO: support microsoft:ds_id
return(HtmlExtractor.Parse(html, new Uri(reqBody.Url)));
}
}
}
// <meta property="microsoft:ds_id" content="some-id">
//private static Regex MetaMicrosoftDsIdRegex = new Regex(@"<meta[^>]+property\s*=\s*[""']microsoft:ds_id[""'][^>]*>", RegexOptions.IgnoreCase | RegexOptions.Compiled);
//private static Regex MetaContentRegex = new Regex(@"content\s*=\s*[""']([^""']+)", RegexOptions.IgnoreCase | RegexOptions.Compiled);
public static async Task <HttpResponseMessage> Run(HttpRequestMessage req, TraceWriter log)
{
CrawlRequest crawlRequest = null;
string reqBodyStr = null;
try
{
using (var operation = Services.TelemetryClient.StartOperation <DependencyTelemetry>("Crawl.HTML"))
{
reqBodyStr = await req.Content.ReadAsStringAsync();
var reqBody = JsonConvert.DeserializeObject <CrawlRequest>(reqBodyStr);
operation.Telemetry.Properties.Add("AppId", reqBody.Site);
operation.Telemetry.Properties.Add("ActionId", reqBody.Id);
operation.Telemetry.Properties.Add("Url", reqBody.Url);
log.Info($"Crawl AppId={reqBody.Site} Id={reqBody.Id} Url={reqBody.Url}");
var request = (HttpWebRequest)WebRequest.Create(reqBody.Url);
if (!string.IsNullOrEmpty(reqBody.ETag))
{
request.Headers.Add(HttpRequestHeader.IfNoneMatch, reqBody.ETag);
}
request.Method = "GET";
request.KeepAlive = true;
request.UserAgent = "DSbot/1.0 (+https://ds.microsoft.com/bot.htm)";
using (var response = (HttpWebResponse)await request.GetResponseAsync())
{
operation.Telemetry.ResultCode = response.StatusCode.ToString();
using (var stream = response.GetResponseStream())
using (var reader = new StreamReader(stream))
{
// TODO: allow direct JSON
// TODO: look for schema.org
var html = await reader.ReadToEndAsync();
// TODO: support microsoft:ds_id
var result = HtmlExtractor.Parse(html, new Uri(reqBody.Url));
result.Url = reqBody.Url;
result.Site = reqBody.Site;
result.Id = reqBody.Id;
return(new HttpResponseMessage(HttpStatusCode.OK)
{
Content = new StringContent(
JsonConvert.SerializeObject(result, new JsonSerializerSettings
{
Formatting = Formatting.None,
StringEscapeHandling = StringEscapeHandling.EscapeNonAscii
}),
new UTF8Encoding(encoderShouldEmitUTF8Identifier: false),
"application/json")
});
}
}
}
}
catch (Exception ex)
{
var props = new Dictionary <string, string>
{
{ "Service", req.RequestUri.ToString() }
};
if (crawlRequest == null)
{
props.Add("JSON", reqBodyStr);
}
else
{
props.Add("Url", crawlRequest.Url);
props.Add("AppId", crawlRequest.Site);
props.Add("ActionId", crawlRequest.Id);
}
Services.TelemetryClient.TrackException(ex, props);
throw ex;
}
}
