Replace json format with protobuf Struct

Dockerfile.tools

@@ -21,7 +21,8 @@ ARG protobuf=3.8.0
 RUN wget -q https://github.com/protocolbuffers/protobuf/releases/download/v$protobuf/protoc-$protobuf-linux-x86_64.zip -O /tmp/protobuf.zip && \
     mkdir /tmp/protobuf && \
     unzip /tmp/protobuf.zip -d /tmp/protobuf && \
-    mv /tmp/protobuf/bin/protoc /usr/local/bin/protoc && \
+    mv /tmp/protobuf/bin/* /usr/local/bin/ && \
+    mv /tmp/protobuf/include/* /usr/local/include/ && \
     rm -rf /tmp/*
 
 RUN go install github.com/go-bindata/go-bindata/go-bindata

protobuf/api/event.proto

@@ -1,5 +1,6 @@
 syntax = "proto3";
 
+import "google/protobuf/struct.proto";
 import "protobuf/types/event.proto";
 
 package api;
@@ -45,7 +46,7 @@ message CreateEventRequest {
   string key = 2;
 
   // data is the data for the event.
-  string data = 3;
+  google.protobuf.Struct data = 3;
 }
 
 // CreateEventResponse defines response for execution update.

protobuf/api/execution.proto

@@ -1,5 +1,6 @@
 syntax = "proto3";
 
+import "google/protobuf/struct.proto";
 import "protobuf/types/execution.proto";
 
 package api;
@@ -29,7 +30,7 @@ service Execution {
 message CreateExecutionRequest {
   string instanceHash = 1;
   string taskKey = 2;
-  string inputs = 3;
+  google.protobuf.Struct inputs = 3;
   repeated string tags = 4;
 }
 
@@ -74,7 +75,7 @@ message UpdateExecutionRequest {
   // result pass to execution
   oneof result {
     // outputs is a success result.
-    string outputs = 2;
+    google.protobuf.Struct outputs = 2;
 
     // error is an error result.
     string error = 3;

protobuf/convert/pbstruct.go

@@ -0,0 +1,44 @@
+package convert
+
+import (
+	"bytes"
+	"encoding/json"
+	"sync"
+
+	"github.com/golang/protobuf/jsonpb"
+	"github.com/golang/protobuf/proto"
+)
+
+var marshaler = jsonpb.Marshaler{EmitDefaults: true}
+
+var bufPool = sync.Pool{
+	New: func() interface{} {
+		return &bytes.Buffer{}
+	},
+}
+
+// Marshal converts protobuf struct to map[string]interface{}.
+func Marshal(in proto.Message, out interface{}) error {
+	buf := bufPool.Get().(*bytes.Buffer)
+	buf.Reset()
+	defer bufPool.Put(buf)
+
+	dec := json.NewDecoder(buf)
+	if err := marshaler.Marshal(buf, in); err != nil {
+		return err
+	}
+	return dec.Decode(out)
+}
+
+// Unmarshal converts map[string]interface{} to protobuf struct.
+func Unmarshal(in interface{}, out proto.Message) error {
+	buf := bufPool.Get().(*bytes.Buffer)
+	buf.Reset()
+	defer bufPool.Put(buf)
+
+	enc := json.NewEncoder(buf)
+	if err := enc.Encode(in); err != nil {
+		return err
+	}
+	return jsonpb.Unmarshal(buf, out)
+}

protobuf/types/event.proto

@@ -1,5 +1,7 @@
 syntax = "proto3";
 
+import "google/protobuf/struct.proto";
+
 package types;
 option go_package = "github.com/mesg-foundation/engine/protobuf/types";
 
@@ -15,5 +17,5 @@ message Event {
   string key = 3;
 
   // data is the data for the event.
-  string data = 4;
+  google.protobuf.Struct data = 4;
 }