/// <summary>
/// Rewrite the URL if it matches any of the URL rewrite rules.
/// </summary>
/// <param name="args">HttpRequest pipeline arguments.</param>
private void RewriteUrl(HttpRequestArgs args)
{
if (!urlRewriteRulesCache.Any())
{
return;
}
// Prepare flags to retrieve the URL strings from Uri objects.
var componentsWithoutQuery = UriComponents.Scheme | UriComponents.Host | UriComponents.Path;
var componentsWithQuery = componentsWithoutQuery | UriComponents.Query;
Uri requestUrl = args.Context.Request.Url;
// If we found a matching URL rewrite rule for the request URL including its querystring,
// we will rewrite to the exact target URL and dispose the request querystring.
// Otherwise, if we found a match for the request URL without its querystring,
// we will rewrite the URL and preserve the querystring from the request.
bool preserveQueryString = false;
// Use the request URL including the querystring to find a matching URL rewrite rule.
UrlRewriteRule rule = urlRewriteRulesCache
.Where(x => x != null)
.FirstOrDefault(x => this.EqualUrl(x.GetSourceUrl(requestUrl), requestUrl, componentsWithQuery));
if (rule == null)
{
// No match was found, try to find a match for the URL without querystring.
rule = urlRewriteRulesCache
.Where(x => x != null)
.FirstOrDefault(x => this.EqualUrl(x.GetSourceUrl(requestUrl), requestUrl, componentsWithoutQuery));
preserveQueryString = rule != null;
}
if (rule == null)
{
// No matching rewrite rule was found.
return;
}
// Set the target URL with or without the original request's querystring.
string targetUrl = preserveQueryString
? string.Concat(rule.GetTargetUrl(requestUrl).GetComponents(componentsWithoutQuery, UriFormat.Unescaped), requestUrl.Query)
: rule.GetTargetUrl(requestUrl).GetComponents(componentsWithQuery, UriFormat.Unescaped);
if (Settings.LogRewrites)
{
// Write an entry to the Sitecore log informing about the rewrite.
Logging.LogInfo(string.Format("URL rewrite rule '{0}' caused the requested URL '{1}' to be rewritten to '{2}'", rule.ItemId, requestUrl.AbsoluteUri, targetUrl), this);
}
// Return a permanent redirect to the target URL.
this.Redirect(targetUrl, args.Context);
}
/// <summary>
/// Add a rewrite rule from Sitecore to the cache.
/// </summary>
/// <param name="rewriteRuleItem"></param>
private void AddRewriteRule(Item rewriteRuleItem)
{
// Convert the rewrite rule item to a model object and add to the cache.
if (rewriteRuleItem.TemplateID.Equals(ItemIds.Templates.UrlRewriteRule))
{
// Add a URL rewrite rule.
var rule = new UrlRewriteRule(rewriteRuleItem);
if (rule.Validate())
{
urlRewriteRulesCache.Add(rule);
}
}
else if (rewriteRuleItem.TemplateID.Equals(ItemIds.Templates.HostNameRewriteRule))
{
// Add a hostname rewrite rule.
var rule = new HostNameRewriteRule(rewriteRuleItem);
if (rule.Validate())
{
hostNameRewriteRulesCache.Add(rule);
}
}
}
