forked from cadey/xesite
88 lines
2.1 KiB
Go
88 lines
2.1 KiB
Go
package analytics
|
|
|
|
import (
|
|
"reflect"
|
|
"strings"
|
|
)
|
|
|
|
// Imitate what what the JSON package would do when serializing a struct value,
|
|
// the only difference is we we don't serialize zero-value struct fields as well.
|
|
// Note that this function doesn't recursively convert structures to maps, only
|
|
// the value passed as argument is transformed.
|
|
func structToMap(v reflect.Value, m map[string]interface{}) map[string]interface{} {
|
|
t := v.Type()
|
|
n := t.NumField()
|
|
|
|
if m == nil {
|
|
m = make(map[string]interface{}, n)
|
|
}
|
|
|
|
for i := 0; i != n; i++ {
|
|
field := t.Field(i)
|
|
value := v.Field(i)
|
|
name, omitempty := parseJsonTag(field.Tag.Get("json"), field.Name)
|
|
|
|
if name != "-" && !(omitempty && isZeroValue(value)) {
|
|
m[name] = value.Interface()
|
|
}
|
|
}
|
|
|
|
return m
|
|
}
|
|
|
|
// Parses a JSON tag the way the json package would do it, returing the expected
|
|
// name of the field once serialized and if empty values should be omitted.
|
|
func parseJsonTag(tag string, defName string) (name string, omitempty bool) {
|
|
args := strings.Split(tag, ",")
|
|
|
|
if len(args) == 0 || len(args[0]) == 0 {
|
|
name = defName
|
|
} else {
|
|
name = args[0]
|
|
}
|
|
|
|
if len(args) > 1 && args[1] == "omitempty" {
|
|
omitempty = true
|
|
}
|
|
|
|
return
|
|
}
|
|
|
|
// Checks if the value given as argument is a zero-value, it is based on the
|
|
// isEmptyValue function in https://golang.org/src/encoding/json/encode.go
|
|
// but also checks struct types recursively.
|
|
func isZeroValue(v reflect.Value) bool {
|
|
switch v.Kind() {
|
|
case reflect.Array, reflect.Map, reflect.Slice, reflect.String:
|
|
return v.Len() == 0
|
|
|
|
case reflect.Bool:
|
|
return !v.Bool()
|
|
|
|
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
|
|
return v.Int() == 0
|
|
|
|
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
|
|
return v.Uint() == 0
|
|
|
|
case reflect.Float32, reflect.Float64:
|
|
return v.Float() == 0
|
|
|
|
case reflect.Interface, reflect.Ptr:
|
|
return v.IsNil()
|
|
|
|
case reflect.Struct:
|
|
for i, n := 0, v.NumField(); i != n; i++ {
|
|
if !isZeroValue(v.Field(i)) {
|
|
return false
|
|
}
|
|
}
|
|
return true
|
|
|
|
case reflect.Invalid:
|
|
return true
|
|
}
|
|
|
|
return false
|
|
}
|