Supporting regex in config path

pkg/kapp/resources/mod_field_copy.go

@@ -5,6 +5,7 @@ package resources
 
 import (
 	"fmt"
+	"regexp"
 )
 
 type FieldCopyModSource string
@@ -30,29 +31,36 @@ func (t FieldCopyMod) IsResourceMatching(res Resource) bool {
 }
 
 func (t FieldCopyMod) ApplyFromMultiple(res Resource, srcs map[FieldCopyModSource]Resource) error {
-	// Make a copy of resource, to avoid modifications
-	// that may be done even in case when there is nothing to copy
-	updatedRes := res.DeepCopy()
-
-	updated, err := t.apply(updatedRes.unstructured().Object, t.Path, Path{}, srcs)
-	if err != nil {
-		return fmt.Errorf("FieldCopyMod for path '%s' on resource '%s': %s", t.Path.AsString(), res.Description(), err)
-	}
-
-	if updated {
-		res.setUnstructured(updatedRes.unstructured())
+	for _, src := range t.Sources {
+		// Make a copy of resource, to avoid modifications
+		// that may be done even in case when there is nothing to copy
+		updatedRes := res.DeepCopy()
+		source, found := srcs[src]
+		if !found {
+			continue
+		}
+		updated, err := t.apply(updatedRes.unstructured().Object, source.unstructured().Object, t.Path, Path{}, srcs)
+		if err != nil {
+			return fmt.Errorf("FieldCopyMod for path '%s' on resource '%s': %s", t.Path.AsString(), res.Description(), err)
+		}
+		if updated {
+			res.setUnstructured(updatedRes.unstructured())
+		}
 	}
-
 	return nil
 }
 
-func (t FieldCopyMod) apply(obj interface{}, path Path, fullPath Path, srcs map[FieldCopyModSource]Resource) (bool, error) {
+func (t FieldCopyMod) apply(obj interface{}, srcObj interface{}, path Path, fullPath Path, srcs map[FieldCopyModSource]Resource) (bool, error) {
 	for i, part := range path {
 		isLast := len(path) == i+1
 		fullPath = append(fullPath, part)
 
 		switch {
 		case part.MapKey != nil:
+			srcTypedObj, ok := srcObj.(map[string]interface{})
+			if !ok {
+				return false, fmt.Errorf("Unexpected non-map found: %T", srcObj)
+			}
 			typedObj, ok := obj.(map[string]interface{})
 			if !ok {
 				return false, fmt.Errorf("Unexpected non-map found: %T", obj)
@@ -62,13 +70,21 @@ func (t FieldCopyMod) apply(obj interface{}, path Path, fullPath Path, srcs map[
 				return t.copyIntoMap(typedObj, fullPath, srcs)
 			}
 
-			var found bool
+			var (
+				found       bool
+				srcObjFound bool
+			)
+			srcObj, srcObjFound = srcTypedObj[*part.MapKey]
+			if !srcObjFound || srcObj == nil {
+				return false, nil
+			}
+
 			obj, found = typedObj[*part.MapKey]
 			// TODO check strictness?
 			if !found || obj == nil {
 				// create empty maps if there are no downstream array indexes;
 				// if there are, we cannot make them anyway, so just exit
-				if path.ContainsNonMapKeys() {
+				if path.ContainsArrayIndex() {
 					return false, nil
 				}
 				obj = map[string]interface{}{}
@@ -87,6 +103,11 @@ func (t FieldCopyMod) apply(obj interface{}, path Path, fullPath Path, srcs map[
 					return false, fmt.Errorf("Unexpected non-array found: %T", obj)
 				}
 
+				srcTypedObj, ok := srcObj.([]interface{})
+				if !ok {
+					return false, fmt.Errorf("Unexpected non-array found: %T", srcObj)
+				}
+
 				var anyUpdated bool
 
 				for objI, obj := range typedObj {
@@ -95,7 +116,11 @@ func (t FieldCopyMod) apply(obj interface{}, path Path, fullPath Path, srcs map[
 					newFullPath := append([]*PathPart{}, fullPath...)
 					newFullPath[len(newFullPath)-1] = &PathPart{ArrayIndex: &PathPartArrayIndex{Index: &objI}}
 
-					updated, err := t.apply(obj, path[i+1:], newFullPath, srcs)
+					var srcTypeObj map[string]interface{}
+					if objI < len(srcTypedObj) {
+						srcTypeObj = srcTypedObj[objI].(map[string]interface{})
+					}
+					updated, err := t.apply(obj, srcTypeObj, path[i+1:], newFullPath, srcs)
 					if err != nil {
 						return false, err
 					}
@@ -112,9 +137,15 @@ func (t FieldCopyMod) apply(obj interface{}, path Path, fullPath Path, srcs map[
 					return false, fmt.Errorf("Unexpected non-array found: %T", obj)
 				}
 
+				srcTypedObj, ok := srcObj.([]interface{})
+				if !ok {
+					return false, fmt.Errorf("Unexpected non-array found: %T", srcObj)
+				}
+
 				if *part.ArrayIndex.Index < len(typedObj) {
 					obj = typedObj[*part.ArrayIndex.Index]
-					return t.apply(obj, path[i+1:], fullPath, srcs)
+					srcObj = srcTypedObj[*part.ArrayIndex.Index]
+					return t.apply(obj, srcObj, path[i+1:], fullPath, srcs)
 				}
 
 				return false, nil // index not found, nothing to append to
@@ -123,6 +154,24 @@ func (t FieldCopyMod) apply(obj interface{}, path Path, fullPath Path, srcs map[
 				panic(fmt.Sprintf("Unknown array index: %#v", part.ArrayIndex))
 			}
 
+		case part.Regex != nil && part.Regex.Regex != nil:
+			matchedKeys, err := t.matchRegexWithSrcObj(*part.Regex.Regex, srcObj)
+			if err != nil {
+				return false, err
+			}
+			allUpdated := true
+			for _, key := range matchedKeys {
+				newPath := append(Path{&PathPart{MapKey: &key}}, path[i+1:]...)
+				newFullPath := fullPath[:len(fullPath)-1]
+				updated, err := t.apply(obj, srcObj, newPath, newFullPath, srcs)
+				if err != nil {
+					return false, err
+				}
+				if !updated {
+					allUpdated = false
+				}
+			}
+			return allUpdated, nil
 		default:
 			panic(fmt.Sprintf("Unexpected path part: %#v", part))
 		}
@@ -203,3 +252,21 @@ func (t FieldCopyMod) obtainValue(obj interface{}, path Path) (interface{}, bool
 
 	return obj, true, nil
 }
+
+func (t FieldCopyMod) matchRegexWithSrcObj(regexString string, srcObj interface{}) ([]string, error) {
+	var matchedKeys []string
+	regex, err := regexp.Compile(regexString)
+	if err != nil {
+		return matchedKeys, err
+	}
+	srcTypedObj, ok := srcObj.(map[string]interface{})
+	if !ok && srcTypedObj != nil {
+		return matchedKeys, fmt.Errorf("Unexpected non-map found: %T", srcObj)
+	}
+	for key := range srcTypedObj {
+		if regex.MatchString(key) {
+			matchedKeys = append(matchedKeys, key)
+		}
+	}
+	return matchedKeys, nil
+}

pkg/kapp/resources/mod_field_remove.go

@@ -5,6 +5,7 @@ package resources
 
 import (
 	"fmt"
+	"regexp"
 )
 
 type FieldRemoveMod struct {
@@ -78,7 +79,6 @@ func (t FieldRemoveMod) apply(obj interface{}, path Path) error {
 						return err
 					}
 				}
-
 				return nil // dealt with children, get out
 
 			case part.ArrayIndex.Index != nil:
@@ -96,6 +96,19 @@ func (t FieldRemoveMod) apply(obj interface{}, path Path) error {
 			default:
 				panic(fmt.Sprintf("Unknown array index: %#v", part.ArrayIndex))
 			}
+		case part.Regex != nil && part.Regex.Regex != nil:
+			matchedKeys, err := t.obtainMatchingRegexKeys(obj, *part.Regex.Regex)
+			if err != nil {
+				return err
+			}
+			for _, key := range matchedKeys {
+				newPath := append(Path{&PathPart{MapKey: &key}}, path[i+1:]...)
+				err := t.apply(obj, newPath)
+				if err != nil {
+					return err
+				}
+			}
+			return nil
 
 		default:
 			panic(fmt.Sprintf("Unexpected path part: %#v", part))
@@ -104,3 +117,21 @@ func (t FieldRemoveMod) apply(obj interface{}, path Path) error {
 
 	panic("unreachable")
 }
+
+func (t FieldRemoveMod) obtainMatchingRegexKeys(obj interface{}, regexString string) ([]string, error) {
+	var matchedKeys []string
+	regex, err := regexp.Compile(regexString)
+	if err != nil {
+		return matchedKeys, err
+	}
+	typedObj, ok := obj.(map[string]interface{})
+	if !ok && typedObj != nil {
+		return matchedKeys, fmt.Errorf("Unexpected non-map found: %T", obj)
+	}
+	for key := range typedObj {
+		if regex.MatchString(key) {
+			matchedKeys = append(matchedKeys, key)
+		}
+	}
+	return matchedKeys, nil
+}

pkg/kapp/resources/mod_object_ref_set.go

@@ -77,6 +77,9 @@ func (t ObjectRefSetMod) apply(obj interface{}, path Path) error {
 				panic(fmt.Sprintf("Unknown array index: %#v", part.ArrayIndex))
 			}
 
+		case part.Regex != nil && part.Regex.Regex != nil:
+			panic(fmt.Sprintf("Regex in path part: %#v is only supported for rebase rules.", part))
+
 		default:
 			panic(fmt.Sprintf("Unexpected path part: %#v", part))
 		}

pkg/kapp/resources/mod_path.go

@@ -22,6 +22,7 @@ type Path []*PathPart
 
 type PathPart struct {
 	MapKey     *string
+	Regex      *PathPartRegex
 	ArrayIndex *PathPartArrayIndex
 }
 
@@ -32,6 +33,10 @@ type PathPartArrayIndex struct {
 	All   *bool `json:"allIndexes"`
 }
 
+type PathPartRegex struct {
+	Regex *string `json:"regex"`
+}
+
 func NewPathFromStrings(strs []string) Path {
 	var path Path
 	for _, str := range strs {
@@ -83,6 +88,15 @@ func (p Path) ContainsNonMapKeys() bool {
 	return false
 }
 
+func (p Path) ContainsArrayIndex() bool {
+	for _, part := range p {
+		if part.ArrayIndex != nil {
+			return true
+		}
+	}
+	return false
+}
+
 func NewPathPartFromString(str string) *PathPart {
 	return &PathPart{MapKey: &str}
 }
@@ -104,6 +118,8 @@ func (p *PathPart) AsString() string {
 		return fmt.Sprintf("%d", *p.ArrayIndex.Index)
 	case p.ArrayIndex != nil && p.ArrayIndex.All != nil:
 		return "(all)"
+	case p.Regex != nil && p.Regex.Regex != nil:
+		return *p.Regex.Regex
 	default:
 		panic("Unknown path part")
 	}
@@ -112,10 +128,13 @@ func (p *PathPart) AsString() string {
 func (p *PathPart) UnmarshalJSON(data []byte) error {
 	var str string
 	var idx PathPartArrayIndex
+	var regx PathPartRegex
 
 	switch {
 	case json.Unmarshal(data, &str) == nil:
 		p.MapKey = &str
+	case json.Unmarshal(data, &regx) == nil && regx.Regex != nil:
+		p.Regex = &regx
 	case json.Unmarshal(data, &idx) == nil:
 		p.ArrayIndex = &idx
 	default:

pkg/kapp/resources/mod_string_map_append.go

@@ -84,6 +84,9 @@ func (t StringMapAppendMod) apply(obj interface{}, path Path) error {
 				panic(fmt.Sprintf("Unknown array index: %#v", part.ArrayIndex))
 			}
 
+		case part.Regex != nil && part.Regex.Regex != nil:
+			panic(fmt.Sprintf("Regex in path part: %#v is only supported for rebase rules.", part))
+
 		default:
 			panic(fmt.Sprintf("Unexpected path part: %#v", part))
 		}