“respError”: “json: unsupported type: func() (io.ReadCloser, error)”

zap library in Golang hit the error on logging a field of the function type.

{"level":"info","msg":"non-200 response","respError":"json: unsupported type: func() (io.ReadCloser, error)"}

The problem is with the type of logger used.

Source code for the above log is:

package main
import (
 "fmt"
 "go.uber.org/zap"
 "log"
 "net/http"
 "net/http/httptest"
)
func main() {
 const body = "Go is…