client: use ugorij/go/codec to unmarshal key response

This change speeds up response unmarshal ~2x:

```
BenchmarkSmallResponseUnmarshal	   20000	     75243 ns/op
BenchmarkManySmallResponseUnmarshal	     200	   6629661 ns/op
BenchmarkMediumResponseUnmarshal	    1000	   1359041 ns/op
BenchmarkLargeResponseUnmarshal	      20	  61600978 ns/op
```

client/keys.generated.go

@@ -0,0 +1,891 @@
+// ************************************************************
+// DO NOT EDIT.
+// THIS FILE IS AUTO-GENERATED BY codecgen.
+// ************************************************************
+
+package client
+
+import (
+	"errors"
+	"fmt"
+	codec1978 "github.com/ugorji/go/codec"
+	"reflect"
+	"runtime"
+	"time"
+)
+
+const (
+	codecSelferC_UTF85311         = 1
+	codecSelferC_RAW5311          = 0
+	codecSelverValueTypeArray5311 = 10
+	codecSelverValueTypeMap5311   = 9
+)
+
+var (
+	codecSelferBitsize5311                         = uint8(reflect.TypeOf(uint(0)).Bits())
+	codecSelferOnlyMapOrArrayEncodeToStructErr5311 = errors.New(`only encoded map or array can be decoded into a struct`)
+)
+
+type codecSelfer5311 struct{}
+
+func init() {
+	if codec1978.GenVersion != 2 {
+		_, file, _, _ := runtime.Caller(0)
+		err := fmt.Errorf("codecgen version mismatch: current: %v, need %v. Re-generate file: %v",
+			2, codec1978.GenVersion, file)
+		panic(err)
+	}
+	if false { // reference the types, but skip this branch at build/run time
+		var v0 time.Time
+		_ = v0
+	}
+}
+
+func (x *Response) CodecEncodeSelf(e *codec1978.Encoder) {
+	var h codecSelfer5311
+	z, r := codec1978.GenHelperEncoder(e)
+	_, _, _ = h, z, r
+	if x == nil {
+		r.EncodeNil()
+	} else {
+		yysep1 := !z.EncBinary()
+		yy2arr1 := z.EncBasicHandle().StructToArray
+		var yyfirst1 bool
+		var yyq1 [3]bool
+		_, _, _, _ = yysep1, yyfirst1, yyq1, yy2arr1
+		const yyr1 bool = false
+		if yyr1 || yy2arr1 {
+			r.EncodeArrayStart(3)
+		} else {
+			var yynn1 int = 3
+			for _, b := range yyq1 {
+				if b {
+					yynn1++
+				}
+			}
+			r.EncodeMapStart(yynn1)
+		}
+		if yyr1 || yy2arr1 {
+			r.EncodeString(codecSelferC_UTF85311, string(x.Action))
+		} else {
+			yyfirst1 = true
+			r.EncodeString(codecSelferC_UTF85311, string("action"))
+			if yysep1 {
+				r.EncodeMapKVSeparator()
+			}
+			r.EncodeString(codecSelferC_UTF85311, string(x.Action))
+		}
+		if yyr1 || yy2arr1 {
+			if yysep1 {
+				r.EncodeArrayEntrySeparator()
+			}
+			if x.Node == nil {
+				r.EncodeNil()
+			} else {
+				x.Node.CodecEncodeSelf(e)
+			}
+		} else {
+			if yyfirst1 {
+				r.EncodeMapEntrySeparator()
+			} else {
+				yyfirst1 = true
+			}
+			r.EncodeString(codecSelferC_UTF85311, string("node"))
+			if yysep1 {
+				r.EncodeMapKVSeparator()
+			}
+			if x.Node == nil {
+				r.EncodeNil()
+			} else {
+				x.Node.CodecEncodeSelf(e)
+			}
+		}
+		if yyr1 || yy2arr1 {
+			if yysep1 {
+				r.EncodeArrayEntrySeparator()
+			}
+			if x.PrevNode == nil {
+				r.EncodeNil()
+			} else {
+				x.PrevNode.CodecEncodeSelf(e)
+			}
+		} else {
+			if yyfirst1 {
+				r.EncodeMapEntrySeparator()
+			} else {
+				yyfirst1 = true
+			}
+			r.EncodeString(codecSelferC_UTF85311, string("prevNode"))
+			if yysep1 {
+				r.EncodeMapKVSeparator()
+			}
+			if x.PrevNode == nil {
+				r.EncodeNil()
+			} else {
+				x.PrevNode.CodecEncodeSelf(e)
+			}
+		}
+		if yysep1 {
+			if yyr1 || yy2arr1 {
+				r.EncodeArrayEnd()
+			} else {
+				r.EncodeMapEnd()
+			}
+		}
+	}
+}
+
+func (x *Response) CodecDecodeSelf(d *codec1978.Decoder) {
+	var h codecSelfer5311
+	z, r := codec1978.GenHelperDecoder(d)
+	_, _, _ = h, z, r
+	if r.IsContainerType(codecSelverValueTypeMap5311) {
+		yyl5 := r.ReadMapStart()
+		if yyl5 == 0 {
+			r.ReadMapEnd()
+		} else {
+			x.codecDecodeSelfFromMap(yyl5, d)
+		}
+	} else if r.IsContainerType(codecSelverValueTypeArray5311) {
+		yyl5 := r.ReadArrayStart()
+		if yyl5 == 0 {
+			r.ReadArrayEnd()
+		} else {
+			x.codecDecodeSelfFromArray(yyl5, d)
+		}
+	} else {
+		panic(codecSelferOnlyMapOrArrayEncodeToStructErr5311)
+	}
+}
+
+func (x *Response) codecDecodeSelfFromMap(l int, d *codec1978.Decoder) {
+	var h codecSelfer5311
+	z, r := codec1978.GenHelperDecoder(d)
+	_, _, _ = h, z, r
+	var yys6Slc = z.DecScratchBuffer() // default slice to decode into
+	_ = yys6Slc
+	var yyhl6 bool = l >= 0
+	for yyj6 := 0; ; yyj6++ {
+		if yyhl6 {
+			if yyj6 >= l {
+				break
+			}
+		} else {
+			if r.CheckBreak() {
+				break
+			}
+			if yyj6 > 0 {
+				r.ReadMapEntrySeparator()
+			}
+		}
+		yys6Slc = r.DecodeBytes(yys6Slc, true, true)
+		yys6 := string(yys6Slc)
+		if !yyhl6 {
+			r.ReadMapKVSeparator()
+		}
+		switch yys6 {
+		case "action":
+			if r.TryDecodeAsNil() {
+				x.Action = ""
+			} else {
+				x.Action = string(r.DecodeString())
+			}
+		case "node":
+			if r.TryDecodeAsNil() {
+				if x.Node != nil {
+					x.Node = nil
+				}
+			} else {
+				if x.Node == nil {
+					x.Node = new(Node)
+				}
+				x.Node.CodecDecodeSelf(d)
+			}
+		case "prevNode":
+			if r.TryDecodeAsNil() {
+				if x.PrevNode != nil {
+					x.PrevNode = nil
+				}
+			} else {
+				if x.PrevNode == nil {
+					x.PrevNode = new(Node)
+				}
+				x.PrevNode.CodecDecodeSelf(d)
+			}
+		default:
+			z.DecStructFieldNotFound(-1, yys6)
+		} // end switch yys6
+	} // end for yyj6
+	if !yyhl6 {
+		r.ReadMapEnd()
+	}
+}
+
+func (x *Response) codecDecodeSelfFromArray(l int, d *codec1978.Decoder) {
+	var h codecSelfer5311
+	z, r := codec1978.GenHelperDecoder(d)
+	_, _, _ = h, z, r
+	var yyj10 int
+	var yyb10 bool
+	var yyhl10 bool = l >= 0
+	yyj10++
+	if yyhl10 {
+		yyb10 = yyj10 > l
+	} else {
+		yyb10 = r.CheckBreak()
+	}
+	if yyb10 {
+		r.ReadArrayEnd()
+		return
+	}
+	if r.TryDecodeAsNil() {
+		x.Action = ""
+	} else {
+		x.Action = string(r.DecodeString())
+	}
+	yyj10++
+	if yyhl10 {
+		yyb10 = yyj10 > l
+	} else {
+		yyb10 = r.CheckBreak()
+	}
+	if yyb10 {
+		r.ReadArrayEnd()
+		return
+	}
+	r.ReadArrayEntrySeparator()
+	if r.TryDecodeAsNil() {
+		if x.Node != nil {
+			x.Node = nil
+		}
+	} else {
+		if x.Node == nil {
+			x.Node = new(Node)
+		}
+		x.Node.CodecDecodeSelf(d)
+	}
+	yyj10++
+	if yyhl10 {
+		yyb10 = yyj10 > l
+	} else {
+		yyb10 = r.CheckBreak()
+	}
+	if yyb10 {
+		r.ReadArrayEnd()
+		return
+	}
+	r.ReadArrayEntrySeparator()
+	if r.TryDecodeAsNil() {
+		if x.PrevNode != nil {
+			x.PrevNode = nil
+		}
+	} else {
+		if x.PrevNode == nil {
+			x.PrevNode = new(Node)
+		}
+		x.PrevNode.CodecDecodeSelf(d)
+	}
+	for {
+		yyj10++
+		if yyhl10 {
+			yyb10 = yyj10 > l
+		} else {
+			yyb10 = r.CheckBreak()
+		}
+		if yyb10 {
+			break
+		}
+		if yyj10 > 1 {
+			r.ReadArrayEntrySeparator()
+		}
+		z.DecStructFieldNotFound(yyj10-1, "")
+	}
+	r.ReadArrayEnd()
+}
+
+func (x *Node) CodecEncodeSelf(e *codec1978.Encoder) {
+	var h codecSelfer5311
+	z, r := codec1978.GenHelperEncoder(e)
+	_, _, _ = h, z, r
+	if x == nil {
+		r.EncodeNil()
+	} else {
+		yysep14 := !z.EncBinary()
+		yy2arr14 := z.EncBasicHandle().StructToArray
+		var yyfirst14 bool
+		var yyq14 [8]bool
+		_, _, _, _ = yysep14, yyfirst14, yyq14, yy2arr14
+		const yyr14 bool = false
+		yyq14[1] = x.Dir != false
+		yyq14[6] = x.Expiration != nil
+		yyq14[7] = x.TTL != 0
+		if yyr14 || yy2arr14 {
+			r.EncodeArrayStart(8)
+		} else {
+			var yynn14 int = 5
+			for _, b := range yyq14 {
+				if b {
+					yynn14++
+				}
+			}
+			r.EncodeMapStart(yynn14)
+		}
+		if yyr14 || yy2arr14 {
+			r.EncodeString(codecSelferC_UTF85311, string(x.Key))
+		} else {
+			yyfirst14 = true
+			r.EncodeString(codecSelferC_UTF85311, string("key"))
+			if yysep14 {
+				r.EncodeMapKVSeparator()
+			}
+			r.EncodeString(codecSelferC_UTF85311, string(x.Key))
+		}
+		if yyr14 || yy2arr14 {
+			if yysep14 {
+				r.EncodeArrayEntrySeparator()
+			}
+			if yyq14[1] {
+				r.EncodeBool(bool(x.Dir))
+			} else {
+				r.EncodeBool(false)
+			}
+		} else {
+			if yyq14[1] {
+				if yyfirst14 {
+					r.EncodeMapEntrySeparator()
+				} else {
+					yyfirst14 = true
+				}
+				r.EncodeString(codecSelferC_UTF85311, string("dir"))
+				if yysep14 {
+					r.EncodeMapKVSeparator()
+				}
+				r.EncodeBool(bool(x.Dir))
+			}
+		}
+		if yyr14 || yy2arr14 {
+			if yysep14 {
+				r.EncodeArrayEntrySeparator()
+			}
+			r.EncodeString(codecSelferC_UTF85311, string(x.Value))
+		} else {
+			if yyfirst14 {
+				r.EncodeMapEntrySeparator()
+			} else {
+				yyfirst14 = true
+			}
+			r.EncodeString(codecSelferC_UTF85311, string("value"))
+			if yysep14 {
+				r.EncodeMapKVSeparator()
+			}
+			r.EncodeString(codecSelferC_UTF85311, string(x.Value))
+		}
+		if yyr14 || yy2arr14 {
+			if yysep14 {
+				r.EncodeArrayEntrySeparator()
+			}
+			if x.Nodes == nil {
+				r.EncodeNil()
+			} else {
+				h.encSlicePtrtoNode(([]*Node)(x.Nodes), e)
+			}
+		} else {
+			if yyfirst14 {
+				r.EncodeMapEntrySeparator()
+			} else {
+				yyfirst14 = true
+			}
+			r.EncodeString(codecSelferC_UTF85311, string("nodes"))
+			if yysep14 {
+				r.EncodeMapKVSeparator()
+			}
+			if x.Nodes == nil {
+				r.EncodeNil()
+			} else {
+				h.encSlicePtrtoNode(([]*Node)(x.Nodes), e)
+			}
+		}
+		if yyr14 || yy2arr14 {
+			if yysep14 {
+				r.EncodeArrayEntrySeparator()
+			}
+			r.EncodeUint(uint64(x.CreatedIndex))
+		} else {
+			if yyfirst14 {
+				r.EncodeMapEntrySeparator()
+			} else {
+				yyfirst14 = true
+			}
+			r.EncodeString(codecSelferC_UTF85311, string("createdIndex"))
+			if yysep14 {
+				r.EncodeMapKVSeparator()
+			}
+			r.EncodeUint(uint64(x.CreatedIndex))
+		}
+		if yyr14 || yy2arr14 {
+			if yysep14 {
+				r.EncodeArrayEntrySeparator()
+			}
+			r.EncodeUint(uint64(x.ModifiedIndex))
+		} else {
+			if yyfirst14 {
+				r.EncodeMapEntrySeparator()
+			} else {
+				yyfirst14 = true
+			}
+			r.EncodeString(codecSelferC_UTF85311, string("modifiedIndex"))
+			if yysep14 {
+				r.EncodeMapKVSeparator()
+			}
+			r.EncodeUint(uint64(x.ModifiedIndex))
+		}
+		if yyr14 || yy2arr14 {
+			if yysep14 {
+				r.EncodeArrayEntrySeparator()
+			}
+			if yyq14[6] {
+				if x.Expiration == nil {
+					r.EncodeNil()
+				} else {
+					z.EncFallback(x.Expiration)
+				}
+			} else {
+				r.EncodeNil()
+			}
+		} else {
+			if yyq14[6] {
+				if yyfirst14 {
+					r.EncodeMapEntrySeparator()
+				} else {
+					yyfirst14 = true
+				}
+				r.EncodeString(codecSelferC_UTF85311, string("expiration"))
+				if yysep14 {
+					r.EncodeMapKVSeparator()
+				}
+				if x.Expiration == nil {
+					r.EncodeNil()
+				} else {
+					z.EncFallback(x.Expiration)
+				}
+			}
+		}
+		if yyr14 || yy2arr14 {
+			if yysep14 {
+				r.EncodeArrayEntrySeparator()
+			}
+			if yyq14[7] {
+				r.EncodeInt(int64(x.TTL))
+			} else {
+				r.EncodeInt(0)
+			}
+		} else {
+			if yyq14[7] {
+				if yyfirst14 {
+					r.EncodeMapEntrySeparator()
+				} else {
+					yyfirst14 = true
+				}
+				r.EncodeString(codecSelferC_UTF85311, string("ttl"))
+				if yysep14 {
+					r.EncodeMapKVSeparator()
+				}
+				r.EncodeInt(int64(x.TTL))
+			}
+		}
+		if yysep14 {
+			if yyr14 || yy2arr14 {
+				r.EncodeArrayEnd()
+			} else {
+				r.EncodeMapEnd()
+			}
+		}
+	}
+}
+
+func (x *Node) CodecDecodeSelf(d *codec1978.Decoder) {
+	var h codecSelfer5311
+	z, r := codec1978.GenHelperDecoder(d)
+	_, _, _ = h, z, r
+	if r.IsContainerType(codecSelverValueTypeMap5311) {
+		yyl23 := r.ReadMapStart()
+		if yyl23 == 0 {
+			r.ReadMapEnd()
+		} else {
+			x.codecDecodeSelfFromMap(yyl23, d)
+		}
+	} else if r.IsContainerType(codecSelverValueTypeArray5311) {
+		yyl23 := r.ReadArrayStart()
+		if yyl23 == 0 {
+			r.ReadArrayEnd()
+		} else {
+			x.codecDecodeSelfFromArray(yyl23, d)
+		}
+	} else {
+		panic(codecSelferOnlyMapOrArrayEncodeToStructErr5311)
+	}
+}
+
+func (x *Node) codecDecodeSelfFromMap(l int, d *codec1978.Decoder) {
+	var h codecSelfer5311
+	z, r := codec1978.GenHelperDecoder(d)
+	_, _, _ = h, z, r
+	var yys24Slc = z.DecScratchBuffer() // default slice to decode into
+	_ = yys24Slc
+	var yyhl24 bool = l >= 0
+	for yyj24 := 0; ; yyj24++ {
+		if yyhl24 {
+			if yyj24 >= l {
+				break
+			}
+		} else {
+			if r.CheckBreak() {
+				break
+			}
+			if yyj24 > 0 {
+				r.ReadMapEntrySeparator()
+			}
+		}
+		yys24Slc = r.DecodeBytes(yys24Slc, true, true)
+		yys24 := string(yys24Slc)
+		if !yyhl24 {
+			r.ReadMapKVSeparator()
+		}
+		switch yys24 {
+		case "key":
+			if r.TryDecodeAsNil() {
+				x.Key = ""
+			} else {
+				x.Key = string(r.DecodeString())
+			}
+		case "dir":
+			if r.TryDecodeAsNil() {
+				x.Dir = false
+			} else {
+				x.Dir = bool(r.DecodeBool())
+			}
+		case "value":
+			if r.TryDecodeAsNil() {
+				x.Value = ""
+			} else {
+				x.Value = string(r.DecodeString())
+			}
+		case "nodes":
+			if r.TryDecodeAsNil() {
+				x.Nodes = nil
+			} else {
+				yyv28 := &x.Nodes
+				h.decSlicePtrtoNode((*[]*Node)(yyv28), d)
+			}
+		case "createdIndex":
+			if r.TryDecodeAsNil() {
+				x.CreatedIndex = 0
+			} else {
+				x.CreatedIndex = uint64(r.DecodeUint(64))
+			}
+		case "modifiedIndex":
+			if r.TryDecodeAsNil() {
+				x.ModifiedIndex = 0
+			} else {
+				x.ModifiedIndex = uint64(r.DecodeUint(64))
+			}
+		case "expiration":
+			if r.TryDecodeAsNil() {
+				if x.Expiration != nil {
+					x.Expiration = nil
+				}
+			} else {
+				if x.Expiration == nil {
+					x.Expiration = new(time.Time)
+				}
+				z.DecFallback(x.Expiration, false)
+			}
+		case "ttl":
+			if r.TryDecodeAsNil() {
+				x.TTL = 0
+			} else {
+				x.TTL = int64(r.DecodeInt(64))
+			}
+		default:
+			z.DecStructFieldNotFound(-1, yys24)
+		} // end switch yys24
+	} // end for yyj24
+	if !yyhl24 {
+		r.ReadMapEnd()
+	}
+}
+
+func (x *Node) codecDecodeSelfFromArray(l int, d *codec1978.Decoder) {
+	var h codecSelfer5311
+	z, r := codec1978.GenHelperDecoder(d)
+	_, _, _ = h, z, r
+	var yyj33 int
+	var yyb33 bool
+	var yyhl33 bool = l >= 0
+	yyj33++
+	if yyhl33 {
+		yyb33 = yyj33 > l
+	} else {
+		yyb33 = r.CheckBreak()
+	}
+	if yyb33 {
+		r.ReadArrayEnd()
+		return
+	}
+	if r.TryDecodeAsNil() {
+		x.Key = ""
+	} else {
+		x.Key = string(r.DecodeString())
+	}
+	yyj33++
+	if yyhl33 {
+		yyb33 = yyj33 > l
+	} else {
+		yyb33 = r.CheckBreak()
+	}
+	if yyb33 {
+		r.ReadArrayEnd()
+		return
+	}
+	r.ReadArrayEntrySeparator()
+	if r.TryDecodeAsNil() {
+		x.Dir = false
+	} else {
+		x.Dir = bool(r.DecodeBool())
+	}
+	yyj33++
+	if yyhl33 {
+		yyb33 = yyj33 > l
+	} else {
+		yyb33 = r.CheckBreak()
+	}
+	if yyb33 {
+		r.ReadArrayEnd()
+		return
+	}
+	r.ReadArrayEntrySeparator()
+	if r.TryDecodeAsNil() {
+		x.Value = ""
+	} else {
+		x.Value = string(r.DecodeString())
+	}
+	yyj33++
+	if yyhl33 {
+		yyb33 = yyj33 > l
+	} else {
+		yyb33 = r.CheckBreak()
+	}
+	if yyb33 {
+		r.ReadArrayEnd()
+		return
+	}
+	r.ReadArrayEntrySeparator()
+	if r.TryDecodeAsNil() {
+		x.Nodes = nil
+	} else {
+		yyv37 := &x.Nodes
+		h.decSlicePtrtoNode((*[]*Node)(yyv37), d)
+	}
+	yyj33++
+	if yyhl33 {
+		yyb33 = yyj33 > l
+	} else {
+		yyb33 = r.CheckBreak()
+	}
+	if yyb33 {
+		r.ReadArrayEnd()
+		return
+	}
+	r.ReadArrayEntrySeparator()
+	if r.TryDecodeAsNil() {
+		x.CreatedIndex = 0
+	} else {
+		x.CreatedIndex = uint64(r.DecodeUint(64))
+	}
+	yyj33++
+	if yyhl33 {
+		yyb33 = yyj33 > l
+	} else {
+		yyb33 = r.CheckBreak()
+	}
+	if yyb33 {
+		r.ReadArrayEnd()
+		return
+	}
+	r.ReadArrayEntrySeparator()
+	if r.TryDecodeAsNil() {
+		x.ModifiedIndex = 0
+	} else {
+		x.ModifiedIndex = uint64(r.DecodeUint(64))
+	}
+	yyj33++
+	if yyhl33 {
+		yyb33 = yyj33 > l
+	} else {
+		yyb33 = r.CheckBreak()
+	}
+	if yyb33 {
+		r.ReadArrayEnd()
+		return
+	}
+	r.ReadArrayEntrySeparator()
+	if r.TryDecodeAsNil() {
+		if x.Expiration != nil {
+			x.Expiration = nil
+		}
+	} else {
+		if x.Expiration == nil {
+			x.Expiration = new(time.Time)
+		}
+		z.DecFallback(x.Expiration, false)
+	}
+	yyj33++
+	if yyhl33 {
+		yyb33 = yyj33 > l
+	} else {
+		yyb33 = r.CheckBreak()
+	}
+	if yyb33 {
+		r.ReadArrayEnd()
+		return
+	}
+	r.ReadArrayEntrySeparator()
+	if r.TryDecodeAsNil() {
+		x.TTL = 0
+	} else {
+		x.TTL = int64(r.DecodeInt(64))
+	}
+	for {
+		yyj33++
+		if yyhl33 {
+			yyb33 = yyj33 > l
+		} else {
+			yyb33 = r.CheckBreak()
+		}
+		if yyb33 {
+			break
+		}
+		if yyj33 > 1 {
+			r.ReadArrayEntrySeparator()
+		}
+		z.DecStructFieldNotFound(yyj33-1, "")
+	}
+	r.ReadArrayEnd()
+}
+
+func (x codecSelfer5311) encSlicePtrtoNode(v []*Node, e *codec1978.Encoder) {
+	var h codecSelfer5311
+	z, r := codec1978.GenHelperEncoder(e)
+	_, _, _ = h, z, r
+	r.EncodeArrayStart(len(v))
+	yys42 := !z.EncBinary()
+	if yys42 {
+		for yyi42, yyv42 := range v {
+			if yyi42 > 0 {
+				r.EncodeArrayEntrySeparator()
+			}
+			if yyv42 == nil {
+				r.EncodeNil()
+			} else {
+				yyv42.CodecEncodeSelf(e)
+			}
+		}
+		r.EncodeArrayEnd()
+	} else {
+		for _, yyv42 := range v {
+			if yyv42 == nil {
+				r.EncodeNil()
+			} else {
+				yyv42.CodecEncodeSelf(e)
+			}
+		}
+	}
+}
+
+func (x codecSelfer5311) decSlicePtrtoNode(v *[]*Node, d *codec1978.Decoder) {
+	var h codecSelfer5311
+	z, r := codec1978.GenHelperDecoder(d)
+	_, _, _ = h, z, r
+
+	yyv43 := *v
+	yyh43, yyl43 := z.DecSliceHelperStart()
+
+	var yyc43 bool
+	_ = yyc43
+
+	if yyv43 == nil {
+		if yyl43 <= 0 {
+			yyv43 = make([]*Node, 0)
+		} else {
+			yyv43 = make([]*Node, yyl43)
+		}
+		yyc43 = true
+	}
+
+	if yyl43 == 0 {
+		if len(yyv43) != 0 {
+			yyv43 = yyv43[:0]
+			yyc43 = true
+		}
+	} else if yyl43 > 0 {
+
+		yyn43 := yyl43
+		if yyl43 > cap(yyv43) {
+			yyv43 = make([]*Node, yyl43, yyl43)
+			yyc43 = true
+
+		} else if yyl43 != len(yyv43) {
+			yyv43 = yyv43[:yyl43]
+			yyc43 = true
+		}
+		yyj43 := 0
+		for ; yyj43 < yyn43; yyj43++ {
+			if r.TryDecodeAsNil() {
+				if yyv43[yyj43] != nil {
+					*yyv43[yyj43] = Node{}
+				}
+			} else {
+				if yyv43[yyj43] == nil {
+					yyv43[yyj43] = new(Node)
+				}
+				yyw44 := yyv43[yyj43]
+				yyw44.CodecDecodeSelf(d)
+			}
+
+		}
+
+	} else {
+		for yyj43 := 0; !r.CheckBreak(); yyj43++ {
+			if yyj43 >= len(yyv43) {
+				yyv43 = append(yyv43, nil) // var yyz43 *Node
+				yyc43 = true
+			}
+			if yyj43 > 0 {
+				yyh43.Sep(yyj43)
+			}
+
+			if yyj43 < len(yyv43) {
+				if r.TryDecodeAsNil() {
+					if yyv43[yyj43] != nil {
+						*yyv43[yyj43] = Node{}
+					}
+				} else {
+					if yyv43[yyj43] == nil {
+						yyv43[yyj43] = new(Node)
+					}
+					yyw45 := yyv43[yyj43]
+					yyw45.CodecDecodeSelf(d)
+				}
+
+			} else {
+				z.DecSwallow()
+			}
+
+		}
+		yyh43.End()
+	}
+	if yyc43 {
+		*v = yyv43
+	}
+
+}

client/keys.go

@@ -14,6 +14,8 @@
 
 package client
 
+//go:generate codecgen -r "Node|Response" -o keys.generated.go keys.go
+
 import (
 	"encoding/json"
 	"errors"
@@ -26,6 +28,7 @@ import (
 	"time"
 
 	"github.com/coreos/etcd/Godeps/_workspace/src/golang.org/x/net/context"
+	"github.com/ugorji/go/codec"
 )
 
 const (
@@ -609,7 +612,7 @@ func unmarshalHTTPResponse(code int, header http.Header, body []byte) (res *Resp
 
 func unmarshalSuccessfulKeysResponse(header http.Header, body []byte) (*Response, error) {
 	var res Response
-	err := json.Unmarshal(body, &res)
+	err := codec.NewDecoderBytes(body, new(codec.JsonHandle)).Decode(&res)
 	if err != nil {
 		return nil, ErrInvalidJSON
 	}