feat: allow removing property rules from validator by ids

internal/uuid/uuid.go

@@ -0,0 +1,17 @@
+package uuid
+
+import (
+	"crypto/rand"
+	"fmt"
+)
+
+func GenerateUUID() string {
+	b := make([]byte, 16)
+	_, _ = rand.Read(b)
+
+	// Set version (4) and variant bits
+	b[6] = (b[6] & 0x0f) | 0x40
+	b[8] = (b[8] & 0x3f) | 0x80
+
+	return fmt.Sprintf("%x-%x-%x-%x-%x", b[0:4], b[4:6], b[6:8], b[8:10], b[10:])
+}

internal/uuid/uuid_test.go

@@ -0,0 +1,54 @@
+package uuid
+
+import (
+	"regexp"
+	"testing"
+
+	"github.com/nobl9/govy/internal/assert"
+)
+
+func TestGenerateUUID(t *testing.T) {
+	t.Run("generates valid UUID format", func(t *testing.T) {
+		id := GenerateUUID()
+
+		// UUID v4 format:
+		pattern := `^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$`
+		matched, err := regexp.MatchString(pattern, id)
+		assert.NoError(t, err)
+		assert.True(t, matched)
+	})
+
+	t.Run("generates unique IDs", func(t *testing.T) {
+		ids := make(map[string]bool)
+		iterations := 1000
+
+		for range iterations {
+			id := GenerateUUID()
+
+			assert.False(t, ids[id])
+			ids[id] = true
+		}
+
+		assert.Equal(t, iterations, len(ids))
+	})
+
+	t.Run("has correct length", func(t *testing.T) {
+		id := GenerateUUID()
+
+		expectedLen := 36 // 32 hex chars + 4 hyphens
+		assert.Equal(t, expectedLen, len(id))
+	})
+
+	t.Run("has correct version bits", func(t *testing.T) {
+		id := GenerateUUID()
+		// Version should be 4 (at position 14)
+		assert.Equal(t, byte('4'), id[14])
+	})
+
+	t.Run("has correct variant bits", func(t *testing.T) {
+		id := GenerateUUID()
+		// Variant should be 8, 9, a, or b (at position 19)
+		variant := id[19]
+		assert.True(t, variant == '8' || variant == '9' || variant == 'a' || variant == 'b')
+	})
+}

pkg/govy/identifier.go

@@ -0,0 +1,27 @@
+package govy
+
+import "github.com/nobl9/govy/internal/uuid"
+
+// instanceID is a composite identifier used to identify [Validator] and [PropertyRules] variations.
+type instanceID struct {
+	// generatedID is always filled and generated upon creation of [instanceID].
+	generatedID string
+	// userSuppliedID overrides generatedID and is supplied by the user.
+	userSuppliedID string
+}
+
+func newInstanceID() instanceID {
+	return instanceID{generatedID: uuid.GenerateUUID()}
+}
+
+func (i instanceID) WithUserSuppliedID(id string) instanceID {
+	i.userSuppliedID = id
+	return i
+}
+
+func (i instanceID) GetID() string {
+	if i.userSuppliedID != "" {
+		return i.userSuppliedID
+	}
+	return i.generatedID
+}

pkg/govy/rules.go

@@ -20,6 +20,7 @@ func For[T, P any](getter PropertyGetter[T, P]) PropertyRules[T, P] {
 // validation will not proceed.
 func ForPointer[T, P any](getter PropertyGetter[*T, P]) PropertyRules[T, P] {
 	return PropertyRules[T, P]{
+		id:       newInstanceID(),
 		pathFunc: getInferPathFunc(getCallersAndProgramCounter(4)),
 		getter: func(parent P) (indirect T, err error) {
 			ptr := getter(parent)
@@ -40,6 +41,7 @@ func ForPointer[T, P any](getter PropertyGetter[*T, P]) PropertyRules[T, P] {
 func Transform[T, N, P any](getter PropertyGetter[T, P], transform Transformer[T, N]) PropertyRules[N, P] {
 	typInfo := typeinfo.Get[T]()
 	return PropertyRules[N, P]{
+		id:       newInstanceID(),
 		pathFunc: getInferPathFunc(getCallersAndProgramCounter(4)),
 		transformGetter: func(parent P) (transformed N, original any, err error) {
 			v := getter(parent)
@@ -60,6 +62,7 @@ func Transform[T, N, P any](getter PropertyGetter[T, P], transform Transformer[T
 // It wraps the getter function in [internalPropertyGetter] and adds path inference.
 func forConstructor[T, P any](getter PropertyGetter[T, P]) PropertyRules[T, P] {
 	return PropertyRules[T, P]{
+		id:       newInstanceID(),
 		pathFunc: getInferPathFunc(getCallersAndProgramCounter(4)),
 		getter:   func(parent P) (v T, err error) { return getter(parent), nil },
 	}
@@ -69,6 +72,7 @@ func forConstructor[T, P any](getter PropertyGetter[T, P]) PropertyRules[T, P] {
 // Used for internal rules in [ForSlice] and [ForMap] where paths are managed separately.
 func forConstructorWithoutPathInference[T, P any](getter PropertyGetter[T, P]) PropertyRules[T, P] {
 	return PropertyRules[T, P]{
+		id:     newInstanceID(),
 		getter: func(parent P) (v T, err error) { return getter(parent), nil },
 	}
 }
@@ -98,6 +102,7 @@ func (emptyErr) Error() string { return "" }
 // It is the middle-level building block of the validation process,
 // aggregated by [Validator] and aggregating [Rule].
 type PropertyRules[T, P any] struct {
+	id               instanceID
 	path             jsonpath.Path
 	pathFunc         inferPathFunc
 	getter           internalPropertyGetter[T, P]
@@ -186,6 +191,13 @@ func (r PropertyRules[T, P]) WithPath(path jsonpath.Path) PropertyRules[T, P] {
 	return r
 }
 
+// WithID sets a unique identifier for these property rules.
+// The identifier can be used with [Validator.RemovePropertiesByID].
+func (r PropertyRules[T, P]) WithID(id string) PropertyRules[T, P] {
+	r.id = r.id.WithUserSuppliedID(id)
+	return r
+}
+
 // WithExamples sets the examples for the property.
 func (r PropertyRules[T, P]) WithExamples(examples ...string) PropertyRules[T, P] {
 	r.examples = append(r.examples, examples...)
@@ -253,6 +265,11 @@ func (r PropertyRules[T, P]) InferPath(mode InferPathMode) PropertyRules[T, P] {
 	return r
 }
 
+// GetID returns the identifier for these property rules.
+func (r PropertyRules[T, P]) GetID() string {
+	return r.id.GetID()
+}
+
 // cascadeInternal is an internal wrapper around [PropertyRules.Cascade] which
 // fulfills [PropertyRulesInterface] interface.
 // If the [CascadeMode] is already set, it won't change it.

pkg/govy/rules_for_map.go

@@ -109,6 +109,12 @@ func (r PropertyRulesForMap[M, K, V, P]) WithPath(path jsonpath.Path) PropertyRu
 	return r
 }
 
+// WithID => refer to [PropertyRules.WithID] documentation.
+func (r PropertyRulesForMap[M, K, V, P]) WithID(id string) PropertyRulesForMap[M, K, V, P] {
+	r.mapRules = r.mapRules.WithID(id)
+	return r
+}
+
 // WithExamples => refer to [PropertyRules.WithExamples] documentation.
 func (r PropertyRulesForMap[M, K, V, P]) WithExamples(examples ...string) PropertyRulesForMap[M, K, V, P] {
 	r.mapRules = r.mapRules.WithExamples(examples...)
@@ -206,6 +212,11 @@ func (r PropertyRulesForMap[M, K, V, P]) InferPath(mode InferPathMode) PropertyR
 	return r
 }
 
+// GetID => refer to [PropertyRules.GetID] documentation.
+func (r PropertyRulesForMap[M, K, V, P]) GetID() string {
+	return r.mapRules.GetID()
+}
+
 // cascadeInternal is an internal wrapper around [PropertyRulesForMap.Cascade] which
 // fulfills [PropertyRulesInterface] interface.
 // If the [CascadeMode] is already set, it won't change it.

pkg/govy/rules_for_slice.go

@@ -78,6 +78,12 @@ func (r PropertyRulesForSlice[S, T, P]) WithPath(path jsonpath.Path) PropertyRul
 	return r
 }
 
+// WithID => refer to [PropertyRules.WithID] documentation.
+func (r PropertyRulesForSlice[S, T, P]) WithID(id string) PropertyRulesForSlice[S, T, P] {
+	r.sliceRules = r.sliceRules.WithID(id)
+	return r
+}
+
 // WithExamples => refer to [PropertyRules.WithExamples] documentation.
 func (r PropertyRulesForSlice[S, T, P]) WithExamples(examples ...string) PropertyRulesForSlice[S, T, P] {
 	r.sliceRules = r.sliceRules.WithExamples(examples...)
@@ -133,6 +139,11 @@ func (r PropertyRulesForSlice[S, T, P]) InferPath(mode InferPathMode) PropertyRu
 	return r
 }
 
+// GetID => refer to [PropertyRules.GetID] documentation.
+func (r PropertyRulesForSlice[S, T, P]) GetID() string {
+	return r.sliceRules.GetID()
+}
+
 // cascadeInternal is an internal wrapper around [PropertyRulesForSlice.Cascade] which
 // fulfills [PropertyRulesInterface] interface.
 // If the [CascadeMode] is already set, it won't change it.

pkg/govy/rules_test.go

@@ -463,6 +463,50 @@ type mockStruct struct {
 	Field string `json:"field"`
 }
 
+func TestPropertyRulesWithID(t *testing.T) {
+	t.Run("property rules", func(t *testing.T) {
+		prop := govy.For(func(m mockStruct) string { return m.Field }).
+			WithName("field").
+			WithID("custom-field-id").
+			Rules(rules.EQ("test"))
+
+		assert.Equal(t, "custom-field-id", prop.GetID())
+	})
+
+	t.Run("slice property rules", func(t *testing.T) {
+		prop := govy.ForSlice(func(m mockStruct) []string { return []string{m.Field} }).
+			WithName("items").
+			WithID("custom-slice-id").
+			Rules(rules.SliceMaxLength[[]string](10))
+
+		assert.Equal(t, "custom-slice-id", prop.GetID())
+	})
+
+	t.Run("map property rules", func(t *testing.T) {
+		prop := govy.ForMap(func(m mockStruct) map[string]string {
+			return map[string]string{"key": m.Field}
+		}).
+			WithName("data").
+			WithID("custom-map-id").
+			Rules(rules.MapMaxLength[map[string]string](10))
+
+		assert.Equal(t, "custom-map-id", prop.GetID())
+	})
+
+	t.Run("WithID creates a copy", func(t *testing.T) {
+		original := govy.For(func(m mockStruct) string { return m.Field }).
+			WithName("field").
+			Rules(rules.EQ("test"))
+
+		originalID := original.GetID()
+		modified := original.WithID("custom-id")
+
+		assert.Equal(t, originalID, original.GetID())
+		assert.Equal(t, "custom-id", modified.GetID())
+		assert.True(t, originalID != modified.GetID())
+	})
+}
+
 func BenchmarkFor(b *testing.B) {
 	for b.Loop() {
 		_ = govy.For(func(m mockStruct) string { return m.Field })

pkg/govy/validation.go

@@ -18,6 +18,7 @@ type ValidatorInterface[T any] interface {
 type PropertyRulesInterface[T any] interface {
 	validationInterface[T]
 	cascadeInternal(mode CascadeMode) PropertyRulesInterface[T]
+	GetID() string
 	getPath() jsonpath.Path
 	inferPathModeInternal(mode InferPathMode) PropertyRulesInterface[T]
 	isPropertyRules()

pkg/govy/validator.go

@@ -8,13 +8,17 @@ import (
 
 // New creates a new [Validator] aggregating the provided property rules.
 func New[T any](props ...PropertyRulesInterface[T]) Validator[T] {
-	return Validator[T]{props: props}
+	return Validator[T]{
+		id:    newInstanceID(),
+		props: props,
+	}
 }
 
 // Validator is the top level validation entity.
 // It serves as an aggregator for [PropertyRules].
 // Typically, it represents a struct.
 type Validator[T any] struct {
+	id          instanceID
 	props       []PropertyRulesInterface[T]
 	name        string
 	nameFunc    func(value T) string
@@ -30,6 +34,12 @@ func (v Validator[T]) WithName(name string) Validator[T] {
 	return v
 }
 
+// WithID sets a unique identifier for this validator.
+func (v Validator[T]) WithID(id string) Validator[T] {
+	v.id = v.id.WithUserSuppliedID(id)
+	return v
+}
+
 // WithNameFunc when a rule fails extracts name from provided function and passes it to [ValidatorError.WithName].
 // The function receives validated entity's instance as an argument.
 func (v Validator[T]) WithNameFunc(f func(value T) string) Validator[T] {
@@ -75,6 +85,23 @@ func (v Validator[T]) RemovePropertiesByPath(paths ...jsonpath.Path) Validator[T
 	return v
 }
 
+// RemovePropertiesByID removes any [PropertyRules] matching the provided identifiers.
+// It returns a modified [Validator] instance without these rules,
+// the original [Validator] is not changed.
+func (v Validator[T]) RemovePropertiesByID(ids ...string) Validator[T] {
+	if len(ids) == 0 {
+		return v
+	}
+	filtered := make([]PropertyRulesInterface[T], 0, len(v.props))
+	for _, prop := range v.props {
+		if !slices.Contains(ids, prop.GetID()) {
+			filtered = append(filtered, prop)
+		}
+	}
+	v.props = filtered
+	return v
+}
+
 // InferPath sets the [InferPathMode] for the validator,
 // which controls relative property path inference for validation rules.
 func (v Validator[T]) InferPath(mode InferPathMode) Validator[T] {
@@ -86,6 +113,11 @@ func (v Validator[T]) InferPath(mode InferPathMode) Validator[T] {
 	return v
 }
 
+// GetID returns the identifier for this validator.
+func (v Validator[T]) GetID() string {
+	return v.id.GetID()
+}
+
 // Validate will first evaluate predicates before validating any rules.
 // If any predicate does not pass the validation won't be executed (returns nil).
 // All errors returned by property rules will be aggregated and wrapped in [ValidatorError].