fix nil buf check

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

codec_test.go

@@ -0,0 +1,19 @@
+package jsonpb
+
+import (
+	"bytes"
+	"testing"
+)
+
+func TestReadBody(t *testing.T) {
+	t.Skip("skip without proto message")
+	s := &struct {
+		Name string
+	}{}
+	c := NewCodec()
+	b := bytes.NewReader(nil)
+	err := c.ReadBody(b, s)
+	if err != nil {
+		t.Fatal(err)
+	}
+}

go.mod

@@ -3,6 +3,6 @@ module github.com/unistack-org/micro-codec-jsonpb/v3
 go 1.16
 
 require (
-	github.com/unistack-org/micro/v3 v3.3.11
+	github.com/unistack-org/micro/v3 v3.3.13
 	google.golang.org/protobuf v1.26.0
 )

go.sum

@@ -7,9 +7,9 @@ github.com/google/uuid v1.2.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+
 github.com/imdario/mergo v0.3.12/go.mod h1:jmQim1M+e3UYxmgPu/WyfjB3N3VflVyUjjjwH0dnCYA=
 github.com/patrickmn/go-cache v2.1.0+incompatible/go.mod h1:3Qf8kWWT7OJRJbdiICTKqZju1ZixQ/KpMGzzAfe6+WQ=
 github.com/silas/dag v0.0.0-20210121180416-41cf55125c34/go.mod h1:7RTUFBdIRC9nZ7/3RyRNH1bdqIShrDejd1YbLwgPS+I=
-github.com/unistack-org/micro/v3 v3.3.11 h1:Jr0gAw5lLqgddiHKQeWUOUeP6ZqgRhz52EA9zJ5MJ3U=
+github.com/unistack-org/micro/v3 v3.3.13 h1:y4bDDkbwnjgOckrhFkC6D/o42tr75X33UbrB+Ko0M68=
-github.com/unistack-org/micro/v3 v3.3.11/go.mod h1:PPCt675o3HPcODFbJ4iRWPmQFAk1WQ+asQSOb/syq6U=
+github.com/unistack-org/micro/v3 v3.3.13/go.mod h1:98hNcMXp/WyWJwLwCuwrhN1Jm7aCWaRNsMfRjK8Fq+Y=
-golang.org/x/net v0.0.0-20210331212208-0fccb6fa2b5c/go.mod h1:p54w0d4576C0XHj96bSt6lcn1PtDYWL6XObtHCRCNQM=
+golang.org/x/net v0.0.0-20210405180319-a5a99cb37ef4/go.mod h1:p54w0d4576C0XHj96bSt6lcn1PtDYWL6XObtHCRCNQM=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210330210617-4fbd30eecc44/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=

jsonpb.go

@@ -39,7 +39,7 @@ func (c *jsonpbCodec) Marshal(v interface{}) ([]byte, error) {
 }
 
 func (c *jsonpbCodec) Unmarshal(d []byte, v interface{}) error {
-	if d == nil {
+	if len(d) == 0 {
 		return nil
 	}
 	switch m := v.(type) {
@@ -65,6 +65,8 @@ func (c *jsonpbCodec) ReadBody(conn io.Reader, b interface{}) error {
 		buf, err := ioutil.ReadAll(conn)
 		if err != nil {
 			return err
+		} else if len(buf) == 0 {
+			return nil
 		}
 		m.Data = buf
 		return nil
@@ -72,6 +74,8 @@ func (c *jsonpbCodec) ReadBody(conn io.Reader, b interface{}) error {
 		buf, err := ioutil.ReadAll(conn)
 		if err != nil {
 			return err
+		} else if len(buf) == 0 {
+			return nil
 		}
 		return JsonpbUnmarshaler.Unmarshal(buf, m)
 	}