private XElement ToImgTag(XElement chartElement, int chartID)
{
ChartIdentity chartIdentity = new ChartIdentity(m_eventID, m_templateID, chartID);
ChartData chartData = s_chartLookup.GetOrAdd(chartIdentity, ident => new ChartData(chartElement, m_contentHash));
// If the cancellation token has been initialized, but we are not able to cancel it,
// it's possible that the action already executed so we attempt to add it back into the lookup
if ((object)chartData.CancellationToken != null && chartData.CancellationToken.Cancel())
{
chartData = s_chartLookup.GetOrAdd(chartIdentity, chartData);
}
// If the content hash of the chart does not match the content hash of the email,
// then the email has changed and we need to update the chart data in the cache
if (chartData.ContentHash != m_contentHash)
{
chartData = s_chartLookup[chartIdentity] = new ChartData(chartElement, m_contentHash);
}
// Create a new cancellation token to remove the chart data from the cache in one minute
chartData.CancellationToken = new Action(() => s_chartLookup.TryRemove(chartIdentity, out chartData)).DelayAndExecute(60 * 1000);
string url = $"EmailTemplateHandler.ashx?EventID={m_eventID}&TemplateID={m_templateID}&ChartID={chartID}";
return(new XElement("img", new XAttribute("src", url)));
}
private void ProcessChartRequest(HttpRequestMessage request, HttpResponseMessage response)
{
ChartData chartData;
XElement chartElement;
string title;
NameValueCollection parameters = request.RequestUri.ParseQueryString();
int chartID = Convert.ToInt32(parameters["chartID"]);
ChartIdentity chartIdentity = new ChartIdentity(m_eventID, m_templateID, chartID);
if (s_chartLookup.TryGetValue(chartIdentity, out chartData))
{
chartElement = chartData.ChartElement;
}
else
{
XDocument doc = XDocument.Parse(ApplyTemplate(request), LoadOptions.PreserveWhitespace);
chartElement = doc.Descendants("chart").Skip(chartID).FirstOrDefault();
}
if ((object)chartElement == null)
{
response.StatusCode = HttpStatusCode.NotFound;
return;
}
title = (string)chartElement.Attribute("yAxisTitle");
using (DataContext dataContext = new DataContext())
using (DbAdapterContainer dbAdapterContainer = new DbAdapterContainer((SqlConnection)dataContext.Connection.Connection))
{
response.Content = new StreamContent(ChartGenerator.ConvertToChartImageStream(dbAdapterContainer, chartElement));
response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment");
response.Content.Headers.ContentDisposition.FileName = title + ".png";
response.Content.Headers.ContentType = new MediaTypeHeaderValue("image/png");
}
}
