/// <summary>
/// Async method that listens for events in the request execution pipeline. Will catch <see cref="CultureNotFoundException"/> and return instructions to redirect the request in the response.
/// </summary>
public async Task Invoke(HttpContext context)
{
try
{
await _next(context);
}
catch (CultureNotFoundException)
{
if (context.Response.HasStarted)
{
throw;
}
var request = context.Request;
var parts = request.Path.Value.Split('/');
parts[_routeCultureOptions.Value.CultureParameterIndex] = CultureInfo.CurrentCulture.Name;
var newPath = (string.IsNullOrWhiteSpace(_responsePath))
? string.Join("/", parts)
: _responsePath;
var newUrl = UrlUtilities.ReplacePath(request, newPath);
_logger.LogRequestCultureNotFoundRedirect(newPath);
context.Response.Clear();
context.Response.StatusCode = _statusCode;
context.Response.Headers[HeaderNames.Location] = newUrl;
return;
}
}
/// <summary>
/// Checks that the <see cref="RouteCultureOptions.LanguageLocaleMap"/> contains the current request culture. If yes, redirects to a URL containing the matching locale.
/// </summary>
/// <param name="context">A <see cref="RewriteContext"/> context</param>
public void ApplyRule(RewriteContext context)
{
var request = context.HttpContext.Request;
var parts = request.Path.Value.Split('/');
var culture = parts[_routeCultureOptions.Value.CultureParameterIndex];
if (!_languageLocaleMap.ContainsKey(culture))
{
context.Result = RuleResult.ContinueRules;
return;
}
foreach (var map in _languageLocaleMap)
{
if (map.Key == culture)
{
parts[_routeCultureOptions.Value.CultureParameterIndex] = map.Value;
break;
}
}
var newPath = string.Join("/", parts);
var newUrl = UrlUtilities.ReplacePath(request, newPath);
var response = context.HttpContext.Response;
response.StatusCode = _statusCode;
response.Headers[HeaderNames.Location] = newUrl;
context.Result = RuleResult.EndResponse;
}
/// <summary>
/// Assesses if request contains a culture parameter. If not, appends current culture name to path and redirects.
/// </summary>
/// <remarks>
/// The redirect URL respects the <see cref="RouteOptions"/> setting as regards whether a trailing slash should be appeneded to the generated URL
/// </remarks>
public Task Invoke(HttpContext context)
{
var request = context.Request;
var parameters = request.Path.Value.Split('/');
var culture = parameters[_routeCultureOptions.Value.CultureParameterIndex];
if (!string.IsNullOrWhiteSpace(culture))
{
return(_next(context));
}
var newPath = $"/{CultureInfo.CurrentCulture.Name}";
if (_routeOptions.Value.AppendTrailingSlash)
{
newPath += "/";
}
var newUrl = UrlUtilities.ReplacePath(request, newPath);
_logger.LogRequiredCultureRedirect(newPath);
context.Response.Clear();
context.Response.StatusCode = _statusCode;
context.Response.Headers[HeaderNames.Location] = newUrl;
return(_next(context));
}
/// <summary>
/// Similar to the GetDisplayUrl() method that extends <see cref="HttpRequest"/>,
/// but allows you to specify a new parameter that will replace an existing parameter
/// </summary>
/// <remarks>Useful for obtaining URLs with alternate culture parameter</remarks>
/// <param name="request">A <see cref="HttpRequest"/> object</param>
/// <param name="parameterIndex">The index of the URL parameter to be replaced</param>
/// <param name="replacementParameter">The new replacement parameter</param>
/// <returns>The new display URL</returns>
public static string GetDisplayUrl(this HttpRequest request, int parameterIndex, string replacementParameter)
{
var parameters = request.Path.Value.Split('/');
if (parameters is null || parameters.Length <= 1)
{
return(request.GetDisplayUrl());
}
parameters[parameterIndex] = replacementParameter;
var newPath = string.Join("/", parameters);
return(UrlUtilities.ReplacePath(request, newPath));
}