use istio client-go library instead of knative (#1661)

use istio client-go library instead of knative
bump kubernetes dependency version
change code coverage to codecov

vendor/sigs.k8s.io/controller-tools/pkg/crd/schema_visitor.go

@@ -0,0 +1,104 @@
+/*
+Copyright 2019 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package crd
+
+import (
+	apiext "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
+)
+
+// SchemaVisitor walks the nodes of a schema.
+type SchemaVisitor interface {
+	// Visit is called for each schema node.  If it returns a visitor,
+	// the visitor will be called on each direct child node, and then
+	// this visitor will be called again with `nil` to indicate that
+	// all children have been visited.  If a nil visitor is returned,
+	// children are not visited.
+	Visit(schema *apiext.JSONSchemaProps) SchemaVisitor
+}
+
+// EditSchema walks the given schema using the given visitor.  Actual
+// pointers to each schema node are passed to the visitor, so any changes
+// made by the visitor will be reflected to the passed-in schema.
+func EditSchema(schema *apiext.JSONSchemaProps, visitor SchemaVisitor) {
+	walker := schemaWalker{visitor: visitor}
+	walker.walkSchema(schema)
+}
+
+// schemaWalker knows how to walk the schema, saving modifications
+// made by the given visitor.
+type schemaWalker struct {
+	visitor SchemaVisitor
+}
+
+// walkSchema walks the given schema, saving modifications made by the
+// visitor (this is as simple as passing a pointer in most cases,
+// but special care needs to be taken to persist with maps).
+func (w schemaWalker) walkSchema(schema *apiext.JSONSchemaProps) {
+	subVisitor := w.visitor.Visit(schema)
+	if subVisitor == nil {
+		return
+	}
+	defer subVisitor.Visit(nil)
+
+	subWalker := schemaWalker{visitor: subVisitor}
+	if schema.Items != nil {
+		subWalker.walkPtr(schema.Items.Schema)
+		subWalker.walkSlice(schema.Items.JSONSchemas)
+	}
+	subWalker.walkSlice(schema.AllOf)
+	subWalker.walkSlice(schema.OneOf)
+	subWalker.walkSlice(schema.AnyOf)
+	subWalker.walkPtr(schema.Not)
+	subWalker.walkMap(schema.Properties)
+	if schema.AdditionalProperties != nil {
+		subWalker.walkPtr(schema.AdditionalProperties.Schema)
+	}
+	subWalker.walkMap(schema.PatternProperties)
+	for name, dep := range schema.Dependencies {
+		subWalker.walkPtr(dep.Schema)
+		schema.Dependencies[name] = dep
+	}
+	if schema.AdditionalItems != nil {
+		subWalker.walkPtr(schema.AdditionalItems.Schema)
+	}
+	subWalker.walkMap(schema.Definitions)
+}
+
+// walkMap walks over values of the given map, saving changes to them.
+func (w schemaWalker) walkMap(defs map[string]apiext.JSONSchemaProps) {
+	for name, def := range defs {
+		w.walkSchema(&def)
+		// make sure the edits actually go through since we can't
+		// take a reference to the value in the map
+		defs[name] = def
+	}
+}
+
+// walkSlice walks over items of the given slice.
+func (w schemaWalker) walkSlice(defs []apiext.JSONSchemaProps) {
+	for i := range defs {
+		w.walkSchema(&defs[i])
+	}
+}
+
+// walkPtr walks over the contents of the given pointer, if it's not nil.
+func (w schemaWalker) walkPtr(def *apiext.JSONSchemaProps) {
+	if def == nil {
+		return
+	}
+	w.walkSchema(def)
+}