Fix crash from inconsistent list members - move null filtering outsid…

…e the realm of cty

provider/resource.go

@@ -261,38 +261,37 @@ func DeepUnknownVal(ty cty.Type) cty.Value {
 	}
 }
 
-func transformRemoveNulls(p cty.Path, v cty.Value) (cty.Value, error) {
-	if v.IsNull() {
-		return v, nil
-	}
-	t := v.Type()
-	switch {
-	case t.IsObjectType():
-		nvals := make(map[string]cty.Value, len(v.Type().AttributeTypes()))
-		for it := v.ElementIterator(); it.Next(); {
-			kv, ev := it.Element()
-			if !ev.IsNull() {
-				nvals[kv.AsString()] = ev
+func mapRemoveNulls(in map[string]interface{}) map[string]interface{} {
+	for k, v := range in {
+		switch tv := v.(type) {
+		case []interface{}:
+			in[k] = sliceRemoveNulls(tv)
+		case map[string]interface{}:
+			in[k] = mapRemoveNulls(tv)
+		default:
+			if v == nil {
+				delete(in, k)
 			}
 		}
-		if len(nvals) == 0 {
-			return cty.NullVal(t), nil
-		}
-		return cty.ObjectVal(nvals), nil
-	case t.IsListType():
-		nvals := []cty.Value{}
-		for et := v.ElementIterator(); et.Next(); {
-			_, val := et.Element()
-			if !val.IsNull() {
-				nvals = append(nvals, val)
+	}
+	return in
+}
+
+func sliceRemoveNulls(in []interface{}) []interface{} {
+	s := []interface{}{}
+	for _, v := range in {
+		switch tv := v.(type) {
+		case []interface{}:
+			s = append(s, sliceRemoveNulls(tv))
+		case map[string]interface{}:
+			s = append(s, mapRemoveNulls(tv))
+		default:
+			if v != nil {
+				s = append(s, v)
 			}
 		}
-		if len(nvals) == 0 {
-			return cty.NullVal(t), nil
-		}
-		return cty.ListVal(nvals), nil
 	}
-	return v, nil
+	return s
 }
 
 func resourceTypeFromOpenAPI(gvk schema.GroupVersionKind) (cty.Type, error) {

provider/resource_test.go

@@ -3,6 +3,7 @@ package provider
 import (
 	"errors"
 	"fmt"
+	"reflect"
 	"strings"
 	"testing"
 
@@ -433,3 +434,64 @@ func TestTypeForPath(t *testing.T) {
 		)
 	}
 }
+
+func TestRemoveNulls(t *testing.T) {
+	samples := []struct {
+		in  map[string]interface{}
+		out map[string]interface{}
+	}{
+		{
+			in: map[string]interface{}{
+				"foo": nil,
+			},
+			out: map[string]interface{}{},
+		},
+		{
+			in: map[string]interface{}{
+				"foo": nil,
+				"bar": "test",
+			},
+			out: map[string]interface{}{
+				"bar": "test",
+			},
+		},
+		{
+			in: map[string]interface{}{
+				"foo": nil,
+				"bar": []interface{}{nil, "test"},
+			},
+			out: map[string]interface{}{
+				"bar": []interface{}{"test"},
+			},
+		},
+		{
+			in: map[string]interface{}{
+				"foo": nil,
+				"bar": []interface{}{
+					map[string]interface{}{
+						"some":  nil,
+						"other": "data",
+					},
+					"test",
+				},
+			},
+			out: map[string]interface{}{
+				"bar": []interface{}{
+					map[string]interface{}{
+						"other": "data",
+					},
+					"test",
+				},
+			},
+		},
+	}
+
+	for i, s := range samples {
+		t.Run(fmt.Sprintf("sample%d", i+1), func(t *testing.T) {
+			o := mapRemoveNulls(s.in)
+			if !reflect.DeepEqual(s.out, o) {
+				t.Fatal("sample and output are not equal")
+			}
+		})
+	}
+}

provider/server.go

@@ -170,7 +170,6 @@ func (s *RawProviderServer) Configure(ctx context.Context, req *tfplugin5.Config
 	ssp := providerConfig.GetAttr("server_side_planning")
 
 	ps[SSPlanning] = ssp.True()
-	Dlog.Printf("[Configure] SSP %s\n", spew.Sdump(ssp))
 	return response, nil
 }
 
@@ -362,19 +361,13 @@ func (s *RawProviderServer) ApplyResourceChange(ctx context.Context, req *tfplug
 				return resp, fmt.Errorf("failed to determine resource type ID: %s", err)
 			}
 
-			// remove null or empty attributes  - the API doesn't appreciate requests that include them
-			so, err := cty.Transform(o, transformRemoveNulls)
-
-			if err != nil {
-				return resp, err
-			}
-
-			mi, err := CtyObjectToUnstructured(&so)
+			mi, err := CtyObjectToUnstructured(&o)
 			if err != nil {
 				return resp, err
 			}
 
-			uo := unstructured.Unstructured{Object: mi}
+			// remove null attributes - the API doesn't appreciate requests that include them
+			uo := unstructured.Unstructured{Object: mapRemoveNulls(mi)}
 			ns, err := IsResourceNamespaced(gvr)
 			if err != nil {
 				return resp, err