/// <summary>
/// Identifies SEO meta tag values in the specified response headers and attempts to injects them into
/// the specified page via content placeholders assumed to exist in the page's master page.
/// </summary>
/// <param name="page">A reference to the current page.</param>
/// <param name="headers">Response headers from an HTTP request.</param>
public static void InjectSeoMetaTagsIntoPage(HttpResponseHeaders headers)
{
if (HttpContext.Current == null)
return;
var page = HttpContext.Current.Handler as Page;
if (page == null || headers == null)
return;
// Look for new values within HTTP headers
IEnumerable<string> seoData = null;
if (headers.TryGetValues(Constants.SeoFields.SeoData, out seoData))
{
// Deserialize new values
var serializer = new DataContractJsonSerializer(typeof(Dictionary<string, string>));
var seoValues = (Dictionary<string, string>)serializer.ReadObject(new MemoryStream(Encoding.UTF8.GetBytes(seoData.First())));
// Get master page placeholder controls
var pageTitleControl = page.Master.FindControl(Constants.ContentPlaceholders.PageTitle);
var seoMetaTagControl = page.Master.FindControl(Constants.ContentPlaceholders.SeoMetaTags);
var canonicalUrlControl = page.Master.FindControl(Constants.ContentPlaceholders.CanonicalUrlMetaTag);
var seoH1Control = page.Master.FindControl(Constants.ContentPlaceholders.SeoH1Tag);
// Inject values into controls
if (pageTitleControl != null && seoValues.ContainsKey(Constants.SeoFields.PageTitle))
{
pageTitleControl.Controls.Clear();
pageTitleControl.Controls.Add(new LiteralControl("<title>" + seoValues[Constants.SeoFields.PageTitle] + "</title>"));
}
if (canonicalUrlControl != null && seoValues.ContainsKey(Constants.SeoFields.CanonicalUrl))
{
canonicalUrlControl.Controls.Clear();
canonicalUrlControl.Controls.Add(new LiteralControl("<link rel=\"canonical\" href=\"" + seoValues[Constants.SeoFields.CanonicalUrl] + "\"/>"));
}
if (seoH1Control != null && seoValues.ContainsKey(Constants.SeoFields.H1))
{
seoH1Control.Controls.Clear();
seoH1Control.Controls.Add(new LiteralControl("<h1 class=\"ih-seo-title\" itemprop=\"name\">" + seoValues[Constants.SeoFields.H1] + "</h1>"));
}
if (seoMetaTagControl != null)
{
var newMetaTags = CreateSeoMetaTagsFromValues(seoValues);
var oldMetaTags = ((LiteralControl)seoMetaTagControl.Controls[0]).Text;
var finalMetaTags = MergeSeoMetaTags(newMetaTags, oldMetaTags);
seoMetaTagControl.Controls.Clear();
seoMetaTagControl.Controls.Add(new LiteralControl(finalMetaTags));
}
}
}
private static long GetHeaderValue(HttpResponseHeaders headers, string name)
{
long result = 0;
IEnumerable<string> values = null;
headers.TryGetValues(name, out values);
string value = values?.FirstOrDefault();
if (value != null)
{
long.TryParse(value, out result);
}
return result;
}
private string GetSettingsVersionHeader(HttpResponseHeaders headers) {
IEnumerable<string> values;
if (headers != null && headers.TryGetValues(ExceptionlessHeaders.ConfigurationVersion, out values))
return values.FirstOrDefault();
return null;
}
public void Set(HttpResponseHeaders headers)
{
IEnumerable<string> values;
if (headers.TryGetValues(TwitterDefinitions.HttpResponse.RateLimit, out values))
{
var limit = values.FirstOrDefault();
if (headers.TryGetValues(TwitterDefinitions.HttpResponse.RateLimitRemaining, out values))
{
var remaining = values.FirstOrDefault();
if (headers.TryGetValues(TwitterDefinitions.HttpResponse.RateLimitReset, out values))
{
var reset = values.FirstOrDefault();
if (limit != null && remaining != null && reset != null)
{
try
{
this.Set(int.Parse(limit), int.Parse(remaining), long.Parse(reset));
}
catch (Exception ex)
{
ex.Write();
}
}
}
}
}
}
