Provide access to admission.Request in custom validator/defaulter

pkg/webhook/admission/defaulter_custom.go

@@ -19,7 +19,6 @@ package admission
 import (
 	"context"
 	"encoding/json"
-
 	"errors"
 	"net/http"
 
@@ -61,6 +60,8 @@ func (h *defaulterForType) Handle(ctx context.Context, req Request) Response {
 		panic("object should never be nil")
 	}
 
+	ctx = NewContextWithRequest(ctx, req)
+
 	// Get the object in the request
 	obj := h.object.DeepCopyObject()
 	if err := h.decoder.Decode(req, obj); err != nil {

pkg/webhook/admission/validator_custom.go

@@ -64,6 +64,8 @@ func (h *validatorForType) Handle(ctx context.Context, req Request) Response {
 		panic("object should never be nil")
 	}
 
+	ctx = NewContextWithRequest(ctx, req)
+
 	// Get the object in the request
 	obj := h.object.DeepCopyObject()
 

pkg/webhook/admission/webhook.go

@@ -253,3 +253,21 @@ func StandaloneWebhook(hook *Webhook, opts StandaloneOptions) (http.Handler, err
 	}
 	return metrics.InstrumentedHook(opts.MetricsPath, hook), nil
 }
+
+// requestContextKey is how we find the admission.Request in a context.Context.
+type requestContextKey struct{}
+
+// RequestFromContext returns an admission.Request from ctx.
+func RequestFromContext(ctx context.Context) (Request, error) {
+	if v, ok := ctx.Value(requestContextKey{}).(Request); ok {
+		return v, nil
+	}
+
+	return Request{}, errors.New("admission.Request not found in context")
+}
+
+// NewContextWithRequest returns a new Context, derived from ctx, which carries the
+// provided admission.Request.
+func NewContextWithRequest(ctx context.Context, req Request) context.Context {
+	return context.WithValue(ctx, requestContextKey{}, req)
+}