Protocol buffer serialization Golang - go

Question

I am using DialogFlow V2 official GoLang SDK. In my webhook, I am returning a payload, which I'm obtaining using the function GetWebhookPayload().
This returns *google_protobuf4.Struct. I would like to turn this struct into a map[string]interface{}. How is this possible?
This is what the struct looks like when serialized:
"payload": {
"fields": {
"messages": {
"Kind": {
"ListValue": {
"values": [
{
"Kind": {
"StructValue": {
"fields": {
"title": {
"Kind": {
"StringValue": "Hi! How can I help?"
}
},
"type": {
"Kind": {
"StringValue": "message"
}
}
}
}
}
}
]
}
}
}
}
What I essentially need is for it to be serialized as such:
"payload": {
"messages": [
{
"title": "Hi! How can I help?",
"type": "message"
}
]
}

Answer 1

This can be solved using jsonpb.
package main
import (
"bytes"
"encoding/json"
"github.com/golang/protobuf/jsonpb"
)
func main() {
...
payload := qr.GetWebhookPayload()
b, marshaler := bytes.Buffer{}, jsonpb.Marshaler{}
if err := marshaler.Marshal(&b, payload.GetFields()["messages"]); err != nil {
// handle err
}
msgs := []interface{}{}
if err := json.Unmarshal(b.Bytes(), &msgs); err != nil {
// handle err
}
// msgs now populated
}