util/reflect: add missing types for merge

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

util/reflect/reflect.go

@@ -3,26 +3,52 @@ package reflect
 import (
 	"errors"
 	"fmt"
+	"net/url"
 	"reflect"
+	"regexp"
 	"strconv"
 	"strings"
+	"unicode"
 )
 
 var (
+	bracketSplitter  = regexp.MustCompile(`\[|\]`)
 	ErrInvalidStruct = errors.New("invalid struct specified")
+	ErrInvalidParam  = errors.New("invalid url query param provided")
 )
 
+func fieldName(name string) string {
+	newstr := make([]rune, 0)
+	upper := false
+	for idx, chr := range name {
+		if idx == 0 {
+			upper = true
+		} else if chr == '_' {
+			upper = true
+			continue
+		}
+		if upper {
+			newstr = append(newstr, unicode.ToUpper(chr))
+		} else {
+			newstr = append(newstr, chr)
+		}
+		upper = false
+	}
+
+	return string(newstr)
+}
+
 func IsEmpty(v reflect.Value) bool {
-	switch v.Kind() {
+	switch getKind(v) {
 	case reflect.Array, reflect.Map, reflect.Slice, reflect.String:
 		return v.Len() == 0
 	case reflect.Bool:
 		return !v.Bool()
-	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+	case reflect.Int:
 		return v.Int() == 0
-	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+	case reflect.Uint:
 		return v.Uint() == 0
-	case reflect.Float32, reflect.Float64:
+	case reflect.Float32:
 		return v.Float() == 0
 	case reflect.Interface, reflect.Ptr:
 		if v.IsNil() {
@@ -123,12 +149,28 @@ func CopyFrom(a, b interface{}) {
 	}
 }
 
-func MergeMap(a interface{}, b map[string]interface{}) error {
+func URLMap(query string) (map[string]interface{}, error) {
-	var err error
+	var (
+		mp interface{} = make(map[string]interface{})
+	)
 
+	params := strings.Split(query, "&")
+
+	for _, part := range params {
+		tm, err := queryToMap(part)
+		if err != nil {
+			return nil, err
+		}
+		mp = merge(mp, tm)
+	}
+
+	return mp.(map[string]interface{}), nil
+}
+
+func FlattenMap(a map[string]interface{}) map[string]interface{} {
 	// preprocess map
-	nb := make(map[string]interface{}, len(b))
+	nb := make(map[string]interface{}, len(a))
-	for k, v := range b {
+	for k, v := range a {
 		ps := strings.Split(k, ".")
 		if len(ps) == 1 {
 			nb[k] = v
@@ -152,6 +194,11 @@ func MergeMap(a interface{}, b map[string]interface{}) error {
 			nb[ps[0]] = em
 		}
 	}
+	return nb
+}
+
+func MergeMap(a interface{}, b map[string]interface{}) error {
+	var err error
 
 	ta := reflect.TypeOf(a)
 	if ta.Kind() == reflect.Ptr {
@@ -162,17 +209,16 @@ func MergeMap(a interface{}, b map[string]interface{}) error {
 		va = va.Elem()
 	}
 
-	for mk, mv := range nb {
+	for mk, mv := range b {
 		vmv := reflect.ValueOf(mv)
-		//		tmv := reflect.TypeOf(mv)
+		name := fieldName(mk)
-		name := strings.Title(mk)
 		fva := va.FieldByName(name)
 		fta, found := ta.FieldByName(name)
 		if !found || !fva.IsValid() || !fva.CanSet() || fta.PkgPath != "" {
 			continue
 		}
 		// fast path via direct assign
-		if vmv.Type().AssignableTo(fta.Type) {
+		if vmv.Type().AssignableTo(fta.Type) && !IsEmpty(vmv) {
 			fva.Set(vmv)
 			continue
 		}
@@ -185,8 +231,37 @@ func MergeMap(a interface{}, b map[string]interface{}) error {
 			err = mergeInt(fva, vmv)
 		case reflect.Uint:
 			err = mergeUint(fva, vmv)
-		case reflect.Float64:
+		case reflect.Float32:
 			err = mergeFloat(fva, vmv)
+		case reflect.Array:
+			//fmt.Printf("Array %#+v %#+v\n", fva, vmv)
+		case reflect.Slice:
+			err = mergeSlice(fva, vmv)
+		case reflect.Ptr:
+			if fva.IsNil() {
+				fva.Set(reflect.New(fva.Type().Elem()))
+				if fva.Elem().Type().Kind() == reflect.Struct {
+					for i := 0; i < fva.Elem().NumField(); i++ {
+						field := fva.Elem().Field(i)
+						if field.Type().Kind() == reflect.Ptr && field.IsNil() && fva.Elem().Type().Field(i).Anonymous == true {
+							field.Set(reflect.New(field.Type().Elem()))
+						}
+					}
+				}
+			}
+			if nmp, ok := vmv.Interface().(map[string]interface{}); ok {
+				err = MergeMap(fva.Interface(), nmp)
+			} else {
+				err = fmt.Errorf("cant fill")
+			}
+		case reflect.Struct:
+			if nmp, ok := vmv.Interface().(map[string]interface{}); ok {
+				err = MergeMap(fva.Interface(), nmp)
+			} else {
+				err = fmt.Errorf("cant fill")
+			}
+		case reflect.Map:
+			//fmt.Printf("Map %#+v %#+v\n", fva, vmv)
 		}
 		if err != nil {
 			return err
@@ -195,6 +270,75 @@ func MergeMap(a interface{}, b map[string]interface{}) error {
 	return nil
 }
 
+func mergeSlice(va, vb reflect.Value) error {
+	switch getKind(vb) {
+	/*
+		case reflect.Int:
+				if vb.Int() == 1 {
+					va.SetBool(true)
+				}
+			case reflect.Uint:
+				if vb.Uint() == 1 {
+					va.SetBool(true)
+				}
+			case reflect.Float64:
+				if vb.Float() == 1 {
+					va.SetBool(true)
+				}
+	*/
+	case reflect.String:
+		var err error
+		fn := func(c rune) bool { return c == ',' || c == ';' || c == ' ' }
+		slice := strings.FieldsFunc(vb.String(), fn)
+		va.Set(reflect.MakeSlice(va.Type(), len(slice), len(slice)))
+		for idx, sl := range slice {
+			vl := reflect.ValueOf(sl)
+			switch va.Type().Elem().Kind() {
+			case reflect.Bool:
+				err = mergeBool(va.Index(idx), vl)
+			case reflect.String:
+				err = mergeString(va.Index(idx), vl)
+			case reflect.Ptr:
+				if va.Index(idx).IsNil() {
+					va.Index(idx).Set(reflect.New(va.Index(idx).Type().Elem()))
+				}
+				switch va.Type().Elem().String() {
+				case "*wrapperspb.BoolValue":
+					if eva := reflect.Indirect(va.Index(idx)).FieldByName("Value"); eva.IsValid() {
+						err = mergeBool(eva, vl)
+					}
+				case "*wrapperspb.BytesValue":
+					if eva := va.Index(idx).FieldByName("Value"); eva.IsValid() {
+						err = mergeUint(eva, vl)
+					}
+				case "*wrapperspb.DoubleValue", "*wrapperspb.FloatValue":
+					if eva := reflect.Indirect(va.Index(idx)).FieldByName("Value"); eva.IsValid() {
+						err = mergeFloat(eva, vl)
+					}
+				case "*wrapperspb.Int32Value", "*wrapperspb.Int64Value":
+					if eva := reflect.Indirect(va.Index(idx)).FieldByName("Value"); eva.IsValid() {
+						err = mergeInt(eva, vl)
+					}
+				case "*wrapperspb.StringValue":
+					if eva := reflect.Indirect(va.Index(idx)).FieldByName("Value"); eva.IsValid() {
+						err = mergeString(eva, vl)
+					}
+				case "*wrapperspb.UInt32Value", "*wrapperspb.UInt64Value":
+					if eva := reflect.Indirect(va.Index(idx)).FieldByName("Value"); eva.IsValid() {
+						err = mergeUint(eva, vl)
+					}
+				}
+			}
+			if err != nil {
+				return err
+			}
+		}
+	default:
+		return fmt.Errorf("cant merge %v %s with %v %s", va, va.Kind(), vb, vb.Kind())
+	}
+	return nil
+}
+
 func mergeBool(va, vb reflect.Value) error {
 	switch getKind(vb) {
 	case reflect.Int:
@@ -205,13 +349,15 @@ func mergeBool(va, vb reflect.Value) error {
 		if vb.Uint() == 1 {
 			va.SetBool(true)
 		}
-	case reflect.Float64:
+	case reflect.Float32:
 		if vb.Float() == 1 {
 			va.SetBool(true)
 		}
 	case reflect.String:
-		if vb.String() == "1" || vb.String() == "true" {
+		if b, err := strconv.ParseBool(vb.String()); err != nil {
-			vb.SetBool(true)
+			return err
+		} else {
+			va.SetBool(b)
 		}
 	default:
 		return fmt.Errorf("cant merge %v %s with %v %s", va, va.Kind(), vb, vb.Kind())
@@ -225,7 +371,7 @@ func mergeString(va, vb reflect.Value) error {
 		va.SetString(fmt.Sprintf("%d", vb.Int()))
 	case reflect.Uint:
 		va.SetString(fmt.Sprintf("%d", vb.Uint()))
-	case reflect.Float64:
+	case reflect.Float32:
 		va.SetString(fmt.Sprintf("%f", vb.Float()))
 	case reflect.String:
 		va.Set(vb)
@@ -241,7 +387,7 @@ func mergeInt(va, vb reflect.Value) error {
 		va.Set(vb)
 	case reflect.Uint:
 		va.SetInt(int64(vb.Uint()))
-	case reflect.Float64:
+	case reflect.Float32:
 		va.SetInt(int64(vb.Float()))
 	case reflect.String:
 		if f, err := strconv.ParseInt(vb.String(), 10, va.Type().Bits()); err != nil {
@@ -261,7 +407,7 @@ func mergeUint(va, vb reflect.Value) error {
 		va.SetUint(uint64(vb.Int()))
 	case reflect.Uint:
 		va.Set(vb)
-	case reflect.Float64:
+	case reflect.Float32:
 		va.SetUint(uint64(vb.Float()))
 	case reflect.String:
 		if f, err := strconv.ParseUint(vb.String(), 10, va.Type().Bits()); err != nil {
@@ -281,7 +427,7 @@ func mergeFloat(va, vb reflect.Value) error {
 		va.SetFloat(float64(vb.Int()))
 	case reflect.Uint:
 		va.SetFloat(float64(vb.Uint()))
-	case reflect.Float64:
+	case reflect.Float32:
 		va.Set(vb)
 	case reflect.String:
 		if f, err := strconv.ParseFloat(vb.String(), va.Type().Bits()); err != nil {
@@ -304,7 +450,148 @@ func getKind(val reflect.Value) reflect.Kind {
 	case kind >= reflect.Uint && kind <= reflect.Uint64:
 		return reflect.Uint
 	case kind >= reflect.Float32 && kind <= reflect.Float64:
-		return reflect.Float64
+		return reflect.Float32
 	}
 	return kind
 }
+
+func btSplitter(str string) []string {
+	r := bracketSplitter.Split(str, -1)
+	for idx, s := range r {
+		if len(s) == 0 {
+			if len(r) > idx+1 {
+				copy(r[idx:], r[idx+1:])
+				r = r[:len(r)-1]
+			}
+		}
+	}
+	return r
+}
+
+// queryToMap turns something like a[b][c]=4 into
+//   map[string]interface{}{
+//     "a": map[string]interface{}{
+// 		  "b": map[string]interface{}{
+// 			  "c": 4,
+// 		  },
+// 	  },
+//   }
+func queryToMap(param string) (map[string]interface{}, error) {
+	rawKey, rawValue, err := splitKeyAndValue(param)
+	if err != nil {
+		return nil, err
+	}
+	rawValue, err = url.QueryUnescape(rawValue)
+	if err != nil {
+		return nil, err
+	}
+	rawKey, err = url.QueryUnescape(rawKey)
+	if err != nil {
+		return nil, err
+	}
+
+	pieces := btSplitter(rawKey)
+	key := pieces[0]
+
+	// If len==1 then rawKey has no [] chars and we can just
+	// decode this as key=value into {key: value}
+	if len(pieces) == 1 {
+		return map[string]interface{}{
+			key: rawValue,
+		}, nil
+	}
+
+	// If len > 1 then we have something like a[b][c]=2
+	// so we need to turn this into {"a": {"b": {"c": 2}}}
+	// To do this we break our key into two pieces:
+	//   a and b[c]
+	// and then we set {"a": queryToMap("b[c]", value)}
+	ret := make(map[string]interface{})
+	ret[key], err = queryToMap(buildNewKey(rawKey) + "=" + rawValue)
+	if err != nil {
+		return nil, err
+	}
+
+	// When URL params have a set of empty brackets (eg a[]=1)
+	// it is assumed to be an array. This will get us the
+	// correct value for the array item and return it as an
+	// []interface{} so that it can be merged properly.
+	if pieces[1] == "" {
+		temp := ret[key].(map[string]interface{})
+		ret[key] = []interface{}{temp[""]}
+	}
+	return ret, nil
+}
+
+// buildNewKey will take something like:
+// origKey = "bar[one][two]"
+// pieces = [bar one two ]
+// and return "one[two]"
+func buildNewKey(origKey string) string {
+	pieces := btSplitter(origKey)
+
+	ret := origKey[len(pieces[0])+1:]
+	ret = ret[:len(pieces[1])] + ret[len(pieces[1])+1:]
+	return ret
+}
+
+// splitKeyAndValue splits a URL param at the last equal
+// sign and returns the two strings. If no equal sign is
+// found, the ErrInvalidParam error is returned.
+func splitKeyAndValue(param string) (string, string, error) {
+	li := strings.LastIndex(param, "=")
+	if li == -1 {
+		return "", "", ErrInvalidParam
+	}
+	return param[:li], param[li+1:], nil
+}
+
+// merge merges a with b if they are either both slices
+// or map[string]interface{} types. Otherwise it returns b.
+func merge(a interface{}, b interface{}) interface{} {
+	if av, aok := a.(map[string]interface{}); aok {
+		if bv, bok := b.(map[string]interface{}); bok {
+			return mergeMapIface(av, bv)
+		}
+	}
+	if av, aok := a.([]interface{}); aok {
+		if bv, bok := b.([]interface{}); bok {
+			return mergeSliceIface(av, bv)
+		}
+	}
+
+	va := reflect.ValueOf(a)
+	vb := reflect.ValueOf(b)
+	if (va.Type().Kind() == reflect.Slice) && (va.Type().Elem().Kind() == vb.Type().Kind() || vb.Type().ConvertibleTo(va.Type().Elem())) {
+		va = reflect.Append(va, vb.Convert(va.Type().Elem()))
+		return va.Interface()
+	}
+
+	return b
+}
+
+// mergeMap merges a with b, attempting to merge any nested
+// values in nested maps but eventually overwriting anything
+// in a that can't be merged with whatever is in b.
+func mergeMapIface(a map[string]interface{}, b map[string]interface{}) map[string]interface{} {
+	for bK, bV := range b {
+		if aV, ok := a[bK]; ok {
+			if (reflect.ValueOf(aV).Type().Kind() == reflect.ValueOf(bV).Type().Kind()) ||
+				((reflect.ValueOf(aV).Type().Kind() == reflect.Slice) && reflect.ValueOf(aV).Type().Elem().Kind() == reflect.ValueOf(bV).Type().Kind()) {
+				nV := []interface{}{aV, bV}
+				a[bK] = nV
+			} else {
+				a[bK] = merge(a[bK], bV)
+			}
+		} else {
+			a[bK] = bV
+		}
+	}
+	return a
+}
+
+// mergeSlice merges a with b and returns the result.
+func mergeSliceIface(a []interface{}, b []interface{}) []interface{} {
+	a = append(a, b...)
+	return a
+}

util/reflect/reflect_test.go

@@ -0,0 +1,45 @@
+package reflect
+
+import (
+	"net/url"
+	"testing"
+)
+
+func TestURLSliceVars(t *testing.T) {
+	u, err := url.Parse("http://localhost/v1/test/call/my_name?key=arg1&key=arg2&key=arg3")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	mp, err := URLMap(u.RawQuery)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	v, ok := mp["key"]
+	if !ok {
+		t.Fatalf("key not exists: %#+v", mp)
+	}
+
+	vm, ok := v.([]interface{})
+	if !ok {
+		t.Fatalf("invalid key value")
+	}
+
+	if len(vm) != 3 {
+		t.Fatalf("missing key value: %#+v", mp)
+	}
+}
+
+func TestURLVars(t *testing.T) {
+	u, err := url.Parse("http://localhost/v1/test/call/my_name?req=key&arg1=arg1&arg2=12345&nested.string_args=str1&nested.string_args=str2&arg2=54321")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	mp, err := URLMap(u.RawQuery)
+	if err != nil {
+		t.Fatal(err)
+	}
+	_ = mp
+}