Add embedded struct support + options

Dean Karn · Dean Karn · commit 920e9aa07439 · 2017-07-30T15:28:01.000-07:00
diff --git a/README.md b/README.md
@@ -1,6 +1,6 @@
 Package form
 ============
-<img align="right" src="https://raw.githubusercontent.com/go-playground/form/master/logo.jpg">![Project status](https://img.shields.io/badge/version-2.3.0-green.svg)
+<img align="right" src="https://raw.githubusercontent.com/go-playground/form/master/logo.jpg">![Project status](https://img.shields.io/badge/version-3.0.0-green.svg)
 [![Build Status](https://semaphoreci.com/api/v1/joeybloggs/form/branches/master/badge.svg)](https://semaphoreci.com/joeybloggs/form)
 [![Coverage Status](https://coveralls.io/repos/github/go-playground/form/badge.svg?branch=master)](https://coveralls.io/github/go-playground/form?branch=master)
 [![Go Report Card](https://goreportcard.com/badge/github.com/go-playground/form)](https://goreportcard.com/report/github.com/go-playground/form)
diff --git a/_examples/decoder-embedded/main.go b/_examples/decoder-embedded/main.go
@@ -0,0 +1,65 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"net/url"
+
+	"github.com/go-playground/form"
+)
+
+// A ...
+type A struct {
+	Field string
+}
+
+// B ...
+type B struct {
+	A
+	Field string
+}
+
+// use a single instance of Decoder, it caches struct info
+var decoder *form.Decoder
+
+func main() {
+	decoder = form.NewDecoder()
+
+	// this simulates the results of http.Request's ParseForm() function
+	values := parseFormB()
+
+	var b B
+
+	// must pass a pointer
+	err := decoder.Decode(&b, values)
+	if err != nil {
+		log.Panic(err)
+	}
+
+	fmt.Printf("%#v\n", b)
+
+	values = parseFormAB()
+
+	// must pass a pointer
+	err = decoder.Decode(&b, values)
+	if err != nil {
+		log.Panic(err)
+	}
+
+	fmt.Printf("%#v\n", b)
+}
+
+// this simulates the results of http.Request's ParseForm() function
+func parseFormB() url.Values {
+	return url.Values{
+		"Field": []string{"B FieldVal"},
+	}
+}
+
+// this simulates the results of http.Request's ParseForm() function
+func parseFormAB() url.Values {
+	return url.Values{
+		"Field":   []string{"B FieldVal"},
+		"A.Field": []string{"A FieldVal"},
+	}
+}
diff --git a/_examples/decoder/full.go b/_examples/decoder/full.go
diff --git a/_examples/encoder-embedded/main.go b/_examples/encoder-embedded/main.go
@@ -0,0 +1,58 @@
+package main
+
+import (
+	"fmt"
+	"log"
+
+	"github.com/go-playground/form"
+)
+
+// A ...
+type A struct {
+	Field string
+}
+
+// B ...
+type B struct {
+	A
+	Field string
+}
+
+// use a single instance of Encoder, it caches struct info
+var encoder *form.Encoder
+
+func main() {
+
+	type A struct {
+		Field string
+	}
+
+	type B struct {
+		A
+		Field string
+	}
+
+	b := B{
+		A: A{
+			Field: "A Val",
+		},
+		Field: "B Val",
+	}
+
+	encoder = form.NewEncoder()
+
+	v, err := encoder.Encode(b)
+	if err != nil {
+		log.Panic(err)
+	}
+
+	fmt.Printf("%#v\n", v)
+
+	encoder.SetAnonymousMode(form.AnonymousSeparate)
+	v, err = encoder.Encode(b)
+	if err != nil {
+		log.Panic(err)
+	}
+
+	fmt.Printf("%#v\n", v)
+}
diff --git a/_examples/encoder/full.go b/_examples/encoder/full.go
diff --git a/cache.go b/cache.go
@@ -2,18 +2,34 @@ package form
 
 import (
 	"reflect"
+	"sort"
 	"strings"
 	"sync"
 	"sync/atomic"
 )
 
+type cacheFields []cachedField
+
+func (s cacheFields) Len() int {
+	return len(s)
+}
+
+func (s cacheFields) Less(i, j int) bool {
+	return !s[i].isAnonymous
+}
+
+func (s cacheFields) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
 type cachedField struct {
-	idx  int
-	name string
+	idx         int
+	name        string
+	isAnonymous bool
 }
 
 type cachedStruct struct {
-	fields []cachedField
+	fields cacheFields
 }
 
 type structCacheMap struct {
@@ -74,6 +90,7 @@ func (s *structCacheMap) parseStruct(mode Mode, current reflect.Value, key refle
 
 		fld = typ.Field(i)
 
+		// fmt.Println("PkgPath:", fld.PkgPath, " Anonymous:", fld.Anonymous, " Name:", fld.Name)
 		if fld.PkgPath != blank && !fld.Anonymous {
 			continue
 		}
@@ -88,6 +105,7 @@ func (s *structCacheMap) parseStruct(mode Mode, current reflect.Value, key refle
 			}
 		}
 
+		// fmt.Println("Ignore:", name == ignore)
 		if name == ignore {
 			continue
 		}
@@ -100,9 +118,10 @@ func (s *structCacheMap) parseStruct(mode Mode, current reflect.Value, key refle
 			name = fld.Name
 		}
 
-		cs.fields = append(cs.fields, cachedField{idx: i, name: name})
+		cs.fields = append(cs.fields, cachedField{idx: i, name: name, isAnonymous: fld.Anonymous})
 	}
 
+	sort.Sort(cs.fields)
 	s.Set(typ, cs)
 
 	s.lock.Unlock()
diff --git a/decoder.go b/decoder.go
@@ -156,6 +156,12 @@ func (d *decoder) traverseStruct(v reflect.Value, typ reflect.Type, namespace []
 
 		namespace = namespace[:l]
 
+		if f.isAnonymous {
+			if d.setFieldByType(v.Field(f.idx), namespace, 0) {
+				set = true
+			}
+		}
+
 		if first {
 			namespace = append(namespace, f.name...)
 		} else {
diff --git a/decoder_test.go b/decoder_test.go
@@ -1506,3 +1506,38 @@ func TestDecoderRegisterTagNameFunc(t *testing.T) {
 	Equal(t, test.Value, "joeybloggs")
 	Equal(t, test.Ignore, "")
 }
+
+func TestDecoderEmbedModes(t *testing.T) {
+
+	type A struct {
+		Field string
+	}
+
+	type B struct {
+		A
+		Field string
+	}
+
+	var b B
+
+	decoder := NewDecoder()
+
+	values := url.Values{
+		"Field": []string{"Value"},
+	}
+
+	err := decoder.Decode(&b, values)
+	Equal(t, err, nil)
+	Equal(t, b.Field, "Value")
+	Equal(t, b.A.Field, "Value")
+
+	values = url.Values{
+		"Field":   []string{"B Val"},
+		"A.Field": []string{"A Val"},
+	}
+
+	err = decoder.Decode(&b, values)
+	Equal(t, err, nil)
+	Equal(t, b.Field, "B Val")
+	Equal(t, b.A.Field, "A Val")
+}
diff --git a/encoder.go b/encoder.go
@@ -49,9 +49,13 @@ func (e *encoder) traverseStruct(v reflect.Value, namespace []byte, idx int) {
 	}
 
 	for _, f := range s.fields {
-
 		namespace = namespace[:l]
 
+		if f.isAnonymous && e.e.embedAnonymous {
+			e.setFieldByType(v.Field(f.idx), namespace, idx)
+			continue
+		}
+
 		if first {
 			namespace = append(namespace, f.name...)
 		} else {
diff --git a/encoder_test.go b/encoder_test.go
@@ -1286,3 +1286,37 @@ func TestEncoderRegisterTagNameFunc(t *testing.T) {
 	Equal(t, len(values), 1)
 	Equal(t, values["name"][0], "Joeybloggs")
 }
+
+func TestEncoderEmbedModes(t *testing.T) {
+
+	type A struct {
+		Field string
+	}
+
+	type B struct {
+		A
+		Field string
+	}
+
+	b := B{
+		A: A{
+			Field: "A Val",
+		},
+		Field: "B Val",
+	}
+
+	encoder := NewEncoder()
+
+	values, err := encoder.Encode(b)
+	Equal(t, err, nil)
+	Equal(t, len(values), 1)
+	Equal(t, values["Field"][0], "B Val")
+	Equal(t, values["Field"][1], "A Val")
+
+	encoder.SetAnonymousMode(AnonymousSeparate)
+	values, err = encoder.Encode(b)
+	Equal(t, err, nil)
+	Equal(t, len(values), 2)
+	Equal(t, values["Field"][0], "B Val")
+	Equal(t, values["A.Field"][0], "A Val")
+}
diff --git a/form.go b/form.go
@@ -30,3 +30,21 @@ const (
 	// and that tag is not the ignore '-' tag
 	ModeExplicit
 )
+
+// AnonymousMode specifies how data should be rolled up
+// or separated from anonymous structs
+type AnonymousMode uint8
+
+const (
+	// AnonymousEmbed embeds anonymous data when encoding
+	// eg. type A struct { Field string }
+	//     type B struct { A, Field string }
+	//     encode results: url.Values{"Field":[]string{"B FieldVal", "A FieldVal"}}
+	AnonymousEmbed AnonymousMode = iota
+
+	// AnonymousSeparate does not embed anonymous data when encoding
+	// eg. type A struct { Field string }
+	//     type B struct { A, Field string }
+	//     encode results: url.Values{"Field":[]string{"B FieldVal"}, "A.Field":[]string{"A FieldVal"}}
+	AnonymousSeparate
+)
diff --git a/form_encoder.go b/form_encoder.go
@@ -49,15 +49,17 @@ type Encoder struct {
 	structCache     *structCacheMap
 	customTypeFuncs map[reflect.Type]EncodeCustomTypeFunc
 	dataPool        *sync.Pool
+	embedAnonymous  bool
 }
 
 // NewEncoder creates a new encoder instance with sane defaults
 func NewEncoder() *Encoder {
 
 	e := &Encoder{
-		tagName:     "form",
-		mode:        ModeImplicit,
-		structCache: newStructCacheMap(),
+		tagName:        "form",
+		mode:           ModeImplicit,
+		structCache:    newStructCacheMap(),
+		embedAnonymous: true,
 	}
 
 	e.dataPool = &sync.Pool{New: func() interface{} {
@@ -82,6 +84,12 @@ func (e *Encoder) SetMode(mode Mode) {
 	e.mode = mode
 }
 
+// SetAnonymousMode sets the mode the encoder should run
+// Default is AnonymousEmbed
+func (e *Encoder) SetAnonymousMode(mode AnonymousMode) {
+	e.embedAnonymous = mode == AnonymousEmbed
+}
+
 // RegisterTagNameFunc registers a custom tag name parser function
 // NOTE: This method is not thread-safe it is intended that these all be registered prior to any parsing
 //
