private void ProcessUrl(object state)
{
MonitoredUrl url = state as MonitoredUrl;
try
{
UrlResponse response = GetResponseForUrl(url);
string emailBody = CheckUrlResponse(response, url);
if (emailBody.Length != 0)
{
SendEmail(url, emailBody);
}
}
catch (Exception ex)
{
string msg = string.Format("Error accessing url {0}, error: {1}", url.Path, ex);
Log.Write(LogLevel.Error, msg);
WebException webException = ex as WebException;
if (webException != null)
{
msg += ", status code: " + ((HttpWebResponse)webException.Response).StatusCode.ToString("D");
SendEmail(url, msg);
}
}
finally
{
url.InProcess = false;
Interlocked.Decrement(ref threadCount);
}
}
private void SendEmail(MonitoredUrl url, string emailBody)
{
SmtpClient client = new SmtpClient();
client.Host = config.Email.Host;
client.Port = config.Email.Port;
client.UseDefaultCredentials = false;
client.Credentials = new NetworkCredential(config.Email.UserName, config.Email.Password);
client.EnableSsl = config.Email.Ssl;
MailMessage msg = new MailMessage
{
Body = emailBody,
BodyEncoding = Encoding.UTF8,
From = new MailAddress(config.Email.UserName, config.Email.From),
IsBodyHtml = true,
Sender = new MailAddress(config.Email.UserName, config.Email.From),
Subject = config.Email.Subject
};
foreach (string address in url.EmailAddresses.Split(',', ';', '|'))
{
string trimmedAddress = address.Trim();
if (trimmedAddress.Length != 0)
{
msg.To.Add(trimmedAddress);
}
}
client.Send(msg);
}
private string CheckUrlResponse(UrlResponse response, MonitoredUrl url)
{
string message = string.Empty;
if (!string.IsNullOrWhiteSpace(url.BodyRegex))
{
if (!Regex.IsMatch(response.Body, url.BodyRegex, RegexOptions.IgnoreCase | RegexOptions.Singleline))
{
message += "- Failed to match body regex<br/>";
}
}
if (!string.IsNullOrWhiteSpace(url.HeadersRegex))
{
bool foundOne = false;
foreach (string header in response.Headers)
{
if (Regex.IsMatch(header, url.HeadersRegex, RegexOptions.IgnoreCase | RegexOptions.Singleline))
{
foundOne = true;
break;
}
}
if (!foundOne)
{
message += "- Failed to match headers regex<br/>";
}
}
if (!string.IsNullOrWhiteSpace(url.StatusCodeRegex))
{
string statusCodeString = response.StatusCode.ToString("D");
if (!Regex.IsMatch(statusCodeString, url.StatusCodeRegex, RegexOptions.IgnoreCase))
{
message += "- Failed to match status code regex, got " + statusCodeString + "<br/>";
}
}
if (url.AlertIfChanged && (url.MD51 != 0 || url.MD52 != 0) && (url.MD51 != response.MD51 || url.MD52 != response.MD52))
{
message += "- MD5 Changed, body contents are new<br/>";
}
if (url.MaxTime.TotalSeconds > 0.0d && response.Duration > url.MaxTime)
{
message += "- URL took " + response.Duration.TotalSeconds.ToString("0.00") + " seconds, too long<br/>";
}
url.MD51 = response.MD51;
url.MD52 = response.MD52;
if (message.Length != 0)
{
if (!string.IsNullOrWhiteSpace(url.MismatchMessage))
{
message = url.MismatchMessage + "<br/>" + message;
}
message = "<a href='" + url.Path + "' title='Url Link'>" + url.Path + "</a><br/>" + message;
}
return(message);
}
private UrlResponse GetResponseForUrl(MonitoredUrl url)
{
DateTime start = DateTime.UtcNow;
HttpWebRequest request = HttpWebRequest.Create(url.Path) as HttpWebRequest;
if (string.IsNullOrWhiteSpace(url.Method))
{
url.Method = "GET";
}
request.Method = url.Method;
foreach (Header header in url.Headers)
{
switch (header.Name.ToUpperInvariant())
{
case "USER-AGENT":
request.UserAgent = header.Value;
break;
default:
request.Headers.Add(header.Name, header.Value);
break;
}
}
if (request.Method.Equals("GET", StringComparison.OrdinalIgnoreCase))
{
// do nothing, we'll just get a response right away
}
else if (request.Method.Equals("POST", StringComparison.OrdinalIgnoreCase) || request.Method.Equals("PUT", StringComparison.OrdinalIgnoreCase))
{
byte[] bytes = (url.PostBytes == null ? Encoding.UTF8.GetBytes(url.PostText) : url.PostBytes);
request.ContentLength = bytes.Length;
using (Stream requestStream = request.GetRequestStream())
{
requestStream.Write(bytes, 0, bytes.Length);
}
}
HttpWebResponse response = request.GetResponse() as HttpWebResponse;
Stream responseStream = response.GetResponseStream();
MemoryStream ms = new MemoryStream();
byte[] buffer = new byte[8192];
int count;
while ((count = responseStream.Read(buffer, 0, buffer.Length)) > 0)
{
ms.Write(buffer, 0, count);
}
string responseBody = Encoding.UTF8.GetString(ms.GetBuffer(), 0, (int)ms.Length);
TimeSpan duration = (DateTime.UtcNow - start);
string[] headers = new string[response.Headers.Count];
int i = 0;
foreach (string key in response.Headers.AllKeys)
{
headers[i++] = key + ":" + response.Headers.Get(key);
}
byte[] md5 = new MD5CryptoServiceProvider().ComputeHash(ms.GetBuffer(), 0, (int)ms.Length);
return(new UrlResponse
{
MD51 = md5[0] | md5[1] << 8 | md5[2] << 16 | md5[3] << 24,
MD52 = md5[4] | md5[5] << 8 | md5[6] << 16 | md5[7] << 24,
Body = responseBody,
Duration = duration,
Headers = headers,
StatusCode = response.StatusCode
});
}
private UrlResponse GetResponseForUrl(MonitoredUrl url)
{
DateTime start = DateTime.UtcNow;
System.Net.ServicePointManager.SecurityProtocol = (SecurityProtocolType)3072; //TLS 1.2
HttpWebRequest request = HttpWebRequest.Create(url.Path) as HttpWebRequest;
// Set the 'Timeout' property of the HttpWebRequest to default value 100,000 milliseconds (100 seconds).
request.Timeout = 100000;
request.KeepAlive = true;
request.ReadWriteTimeout = 100000;
if (!url.AllowRedirects)
{
request.AllowAutoRedirect = false;
}
if (string.IsNullOrWhiteSpace(url.Method))
{
url.Method = "GET";
}
request.Method = url.Method;
foreach (Header header in url.Headers)
{
switch (header.Name.ToUpperInvariant())
{
case "USER-AGENT":
request.UserAgent = header.Value;
break;
default:
request.Headers.Add(header.Name, header.Value);
break;
}
}
if (request.Method.Equals("GET", StringComparison.OrdinalIgnoreCase))
{
// do nothing, we'll just get a response right away
}
else if (request.Method.Equals("POST", StringComparison.OrdinalIgnoreCase) || request.Method.Equals("PUT", StringComparison.OrdinalIgnoreCase))
{
byte[] bytes = (url.PostBytes == null ? Encoding.UTF8.GetBytes(url.PostText) : url.PostBytes);
request.ContentLength = bytes.Length;
using (Stream requestStream = request.GetRequestStream())
{
requestStream.Write(bytes, 0, bytes.Length);
}
}
HttpWebResponse response = request.GetResponse() as HttpWebResponse;
Stream responseStream = response.GetResponseStream();
string data;
using (StreamReader reader = new StreamReader(responseStream))
{
responseStream.Flush();
data = reader.ReadToEnd();
}
var doc = new HtmlDocument();
doc.LoadHtml(data);
HtmlNode RootNode = doc.DocumentNode;
HtmlNodeCollection nodes = new HtmlNodeCollection(RootNode);
if (!string.IsNullOrEmpty(url.FilterElements))
{
string[] words = url.FilterElements.Split(',');
foreach (string word in words)
{
doc.DocumentNode.SelectNodes(word)?.ToList().ForEach(a => a.Remove());
}
}
// From string to byte array
byte[] buffer = Encoding.UTF8.GetBytes(RootNode.OuterHtml);
// From byte array to string
string responseBody = Encoding.UTF8.GetString(buffer, 0, buffer.Length);
TimeSpan duration = (DateTime.UtcNow - start);
string[] headers = new string[response.Headers.Count];
int i = 0;
foreach (string key in response.Headers.AllKeys)
{
headers[i++] = key + ":" + response.Headers.Get(key);
}
byte[] md5 = new MD5CryptoServiceProvider().ComputeHash(buffer, 0, buffer.Length);
return(new UrlResponse
{
MD51 = md5[0] | md5[1] << 8 | md5[2] << 16 | md5[3] << 24,
MD52 = md5[4] | md5[5] << 8 | md5[6] << 16 | md5[7] << 24,
Body = responseBody,
Duration = duration,
Headers = headers,
StatusCode = response.StatusCode
});
}