private static StructuredTransformer CreateTransformer(TransformBuilderContext context)
{
// RequestHeaderOriginalHostKey defaults to false, and CopyRequestHeaders defaults to true.
// If RequestHeaderOriginalHostKey was not specified then we need to make sure the transform gets
// added anyways to remove the original host. If CopyRequestHeaders is false then we can omit the
// transform.
if (context.CopyRequestHeaders.GetValueOrDefault(true) &&
!context.RequestTransforms.Any(item => item is RequestHeaderOriginalHostTransform))
{
context.AddOriginalHost(false);
}
// Add default forwarders only if they haven't already been added or disabled.
if (context.UseDefaultForwarders.GetValueOrDefault(true))
{
context.AddXForwarded();
}
return(new StructuredTransformer(
context.CopyRequestHeaders,
context.CopyResponseHeaders,
context.CopyResponseTrailers,
context.RequestTransforms,
context.ResponseTransforms,
context.ResponseTrailersTransforms));
}
internal static void RemoveAllXForwardedHeaders(TransformBuilderContext context, string prefix)
{
context.AddXForwardedFor(prefix + ForwardedTransformFactory.ForKey, ForwardedTransformActions.Remove);
context.AddXForwardedPrefix(prefix + ForwardedTransformFactory.PrefixKey, ForwardedTransformActions.Remove);
context.AddXForwardedHost(prefix + ForwardedTransformFactory.HostKey, ForwardedTransformActions.Remove);
context.AddXForwardedProto(prefix + ForwardedTransformFactory.ProtoKey, ForwardedTransformActions.Remove);
}
internal StructuredTransformer CreateInternal(Action <TransformBuilderContext> action)
{
var context = new TransformBuilderContext
{
Services = _services,
};
action(context);
return(CreateTransformer(context));
}
// This is separate from Build for testing purposes.
internal StructuredTransformer BuildInternal(RouteConfig route, ClusterConfig?cluster)
{
var rawTransforms = route.Transforms;
var context = new TransformBuilderContext
{
Services = _services,
Route = route,
Cluster = cluster,
};
if (rawTransforms?.Count > 0)
{
foreach (var rawTransform in rawTransforms)
{
var handled = false;
foreach (var factory in _factories)
{
if (factory.Build(context, rawTransform))
{
handled = true;
break;
}
}
if (!handled)
{
throw new ArgumentException($"Unknown transform: {string.Join(';', rawTransform.Keys)}");
}
}
}
// Let the app add any more transforms it wants.
foreach (var transformProvider in _providers)
{
transformProvider.Apply(context);
}
return(CreateTransformer(context));
}
public void Apply(TransformBuilderContext transformBuildContext)
{
_action(transformBuildContext);
}
internal static void RemoveForwardedHeader(TransformBuilderContext context)
{
context.RequestTransforms.Add(RequestHeaderForwardedTransform.RemoveTransform);
}
