/// <summary>
/// Helper for localizing an individual URL string for a particular langtag value
/// and URL of the current request.
/// </summary>
/// <param name="url">Subject URL to be localized.</param>
/// <param name="langtag">Language with which to localize the URL.</param>
/// <param name="requestUrl">URL of the current HTTP request being handled.</param>
/// <returns>
/// String describing the new localized URL, or null if the URL was not localized,
/// either because it was already localized, or because it is from another host, or is explicitly
/// excluded from localization by the filter.
/// </returns>
protected string LocalizeUrl(HttpContextBase context, string url, string langtag, Uri requestUrl, bool incomingUrl)
{
// If URL is already localized...leave matched token alone.
string urlNonlocalized;
if (m_urlLocalizer.ExtractLangTagFromUrl(context, url, UriKind.RelativeOrAbsolute, incomingUrl, out urlNonlocalized) != null) {
return null; } // original
// If URL is not local (i.e. remote host)...leave matched token alone.
if (requestUrl != null && !requestUrl.IsLocal(url)) {
return null; } // original
// Is URL explicitly excluded from localization?
if (!m_urlLocalizer.FilterOutgoing(url, requestUrl)) {
return null; } // original
// Localize the URL.
return m_urlLocalizer.SetLangTagInUrlPath(context, url, UriKind.RelativeOrAbsolute, langtag);
}
/// <summary>
/// Helper for localizing an individual URL string for a particular langtag value
/// and URL of the current request.
/// </summary>
/// <param name="url">Subject URL to be localized.</param>
/// <param name="langtag">Language with which to localize the URL.</param>
/// <param name="requestUrl">URL of the current HTTP request being handled.</param>
/// <returns>
/// String describing the new localized URL, or null if the URL was not localized,
/// either because it was already localized, or because it is from another host, or is explicitly
/// excluded from localization by the filter.
/// </returns>
protected string LocalizeUrl(System.Web.HttpContextBase context, string url, string langtag, Uri requestUrl, bool incomingUrl)
{
// If URL has prefix indicating it should be excluded from localization...return unlocalized URL
if (url.StartsWith(IgnoreLocalizationUrlPrefix)) {
return url.Substring(IgnoreLocalizationUrlPrefix.Length); }
// If URL is already localized...leave matched token alone.
string urlNonlocalized;
if (m_urlLocalizer.ExtractLangTagFromUrl(context, url, UriKind.RelativeOrAbsolute, incomingUrl, out urlNonlocalized) != null) {
return null; } // original
// If URL is not local (i.e. remote host)...leave matched token alone.
if (requestUrl != null && !requestUrl.IsLocal(url)) {
return null; } // original
// Is URL explicitly excluded from localization?
if (!m_urlLocalizer.FilterOutgoing(url, requestUrl)) {
return null; } // original
// Localize the URL.
return m_urlLocalizer.SetLangTagInUrlPath(context, url, UriKind.RelativeOrAbsolute, langtag);
}
/// <summary>
/// Helper for localizing an individual URL string for a particular langtag value
/// and URL of the current request.
/// </summary>
/// <param name="url">Subject URL to be localized.</param>
/// <param name="langtag">Language with which to localize the URL.</param>
/// <param name="requestUrl">URL of the current HTTP request being handled.</param>
/// <returns>
/// String describing the new localized URL, or null if the URL was not localized,
/// either because it was already localized, or because it is from another host, or is explicitly
/// excluded from localization by the filter.
/// </returns>
protected string LocalizeUrl(System.Web.HttpContextBase context, string url, string langtag, Uri requestUrl, bool incomingUrl)
{
// If URL has prefix indicating it should be excluded from localization...return unlocalized URL
if (url.StartsWith(IgnoreLocalizationUrlPrefix)) {
return url.Substring(IgnoreLocalizationUrlPrefix.Length); }
// If URL is already localized...leave matched token alone.
string urlNonlocalized;
if (m_urlLocalizer.ExtractLangTagFromUrl(context, url, UriKind.RelativeOrAbsolute, incomingUrl, out urlNonlocalized) != null) {
return null; } // original
// If URL is not local (i.e. remote host)...leave matched token alone.
if (requestUrl != null && !requestUrl.IsLocal(url)) {
return null; } // original
// Is URL explicitly excluded from localization?
if (!m_urlLocalizer.FilterOutgoing(url, requestUrl)) {
return null; } // original
// If url is un-rooted...make it rooted based on any current request URL.
// This is to resolve problems caused to i18n with resource URL paths relative to the
// current page (see issue #286).
// By un-rooted we mean the url is not absolute (i.e. it starts from the path component),
// and that that path component itself is a relative path (i.e. it doesn't start with a /).
// In doing so we also eliminate any "../..", "./", etc.
// Examples:
// url (before) requestUrl url (after)
// -------------------------------------------------------------------------------------------------------------------
// content/fred.jpg http://example.com/blog/ /blog/content/fred.jpg (changed)
// content/fred.jpg http://example.com/blog /content/fred.jpg (changed)
// /content/fred.jpg http://example.com/blog/ /content/fred.jpg (unchanged)
// http://example.com/content/fred.jpg http://example.com/blog/ http://example.com/content/fred.jpg (unchanged)
// See also test cases in ResponseFilterTests.ResponseFilter_can_patch_html_urls.
//
if (requestUrl != null) {
bool urlIsUnrooted = !url.StartsWith("/")
&& (!url.Contains(":") || !Uri.IsWellFormedUriString(url, UriKind.Absolute));
// NB: the above is somewhat elaborate so as to avoid an object allocation
// in all but edge cases. Note also that Uri.IsWellFormedUriString internally
// simply does a Uri.TryCreate (at least as of .NET 4.6.1).
if (urlIsUnrooted) {
Uri newUri = new Uri(requestUrl, url);
url = newUri.PathAndQuery;
}
}
// Localize the URL.
return m_urlLocalizer.SetLangTagInUrlPath(context, url, UriKind.RelativeOrAbsolute, langtag);
}
