index: Add *String functions

Add *String counterparts (Int32 => Int32String) for implementing FromString
in Index[].

Signed-off-by: Jussi Maki <jussi.maki@isovalent.com>

db_test.go

@@ -66,12 +66,9 @@ var (
 		FromObject: func(t testObject) index.KeySet {
 			return index.NewKeySet(index.Uint64(t.ID))
 		},
-		FromKey: index.Uint64,
-		FromString: func(key string) (index.Key, error) {
-			v, err := strconv.ParseUint(key, 10, 64)
-			return index.Uint64(v), err
-		},
-		Unique: true,
+		FromKey:    index.Uint64,
+		FromString: index.Uint64String,
+		Unique:     true,
 	}
 
 	tagsIndex = Index[testObject, string]{

index/bool.go

@@ -3,6 +3,8 @@
 
 package index
 
+import "strconv"
+
 var (
 	trueKey  = []byte{'T'}
 	falseKey = []byte{'F'}
@@ -14,3 +16,8 @@ func Bool(b bool) Key {
 	}
 	return falseKey
 }
+
+func BoolString(s string) (Key, error) {
+	b, err := strconv.ParseBool(s)
+	return Bool(b), err
+}

index/int.go

@@ -5,6 +5,7 @@ package index
 
 import (
 	"encoding/binary"
+	"strconv"
 )
 
 // The indexing functions on integers should use big-endian encoding.
@@ -19,26 +20,78 @@ func Int(n int) Key {
 	return Int32(int32(n))
 }
 
+func IntString(s string) (Key, error) {
+	return Int32String(s)
+}
+
 func Int64(n int64) Key {
 	return Uint64(uint64(n))
 }
 
+func Int64String(s string) (Key, error) {
+	n, err := strconv.ParseInt(s, 10, 64)
+	if err != nil {
+		return Key{}, err
+	}
+	return Uint64(uint64(n)), nil
+}
+
 func Int32(n int32) Key {
 	return Uint32(uint32(n))
 }
 
+func Int32String(s string) (Key, error) {
+	n, err := strconv.ParseInt(s, 10, 32)
+	if err != nil {
+		return Key{}, err
+	}
+	return Uint32(uint32(n)), nil
+}
+
 func Int16(n int16) Key {
 	return Uint16(uint16(n))
 }
 
+func Int16String(s string) (Key, error) {
+	n, err := strconv.ParseInt(s, 10, 16)
+	if err != nil {
+		return Key{}, err
+	}
+	return Uint16(uint16(n)), nil
+}
+
 func Uint64(n uint64) Key {
 	return binary.BigEndian.AppendUint64(nil, n)
 }
 
+func Uint64String(s string) (Key, error) {
+	n, err := strconv.ParseUint(s, 10, 64)
+	if err != nil {
+		return Key{}, err
+	}
+	return Uint64(n), nil
+}
+
 func Uint32(n uint32) Key {
 	return binary.BigEndian.AppendUint32(nil, n)
 }
 
+func Uint32String(s string) (Key, error) {
+	n, err := strconv.ParseUint(s, 10, 32)
+	if err != nil {
+		return Key{}, err
+	}
+	return Uint32(uint32(n)), nil
+}
+
 func Uint16(n uint16) Key {
 	return binary.BigEndian.AppendUint16(nil, n)
 }
+
+func Uint16String(s string) (Key, error) {
+	n, err := strconv.ParseUint(s, 10, 16)
+	if err != nil {
+		return Key{}, err
+	}
+	return Uint16(uint16(n)), nil
+}

index/netip.go

@@ -20,8 +20,24 @@ func NetIPAddr(addr netip.Addr) Key {
 	return buf[:]
 }
 
+func NetIPAddrString(s string) (Key, error) {
+	addr, err := netip.ParseAddr(s)
+	if err != nil {
+		return Key{}, err
+	}
+	return NetIPAddr(addr), nil
+}
+
 func NetIPPrefix(prefix netip.Prefix) Key {
 	// Use the 16-byte form plus bits to have a constant-size key.
 	addrBytes := prefix.Addr().As16()
 	return append(addrBytes[:], uint8(prefix.Bits()))
 }
+
+func NetIPPrefixString(s string) (Key, error) {
+	prefix, err := netip.ParsePrefix(s)
+	if err != nil {
+		return Key{}, err
+	}
+	return NetIPPrefix(prefix), nil
+}