func fieldConvert()

in plugins/inputs/snmp/snmp.go [671:825]
143 lines of code
52 McCabe index (conditional complexity)

func fieldConvert(conv string, v interface{}) (interface{}, error) {
	if conv == "" {
		if bs, ok := v.([]byte); ok {
			return string(bs), nil
		}
		return v, nil
	}

	var d int
	if _, err := fmt.Sscanf(conv, "float(%d)", &d); err == nil || conv == "float" {
		switch vt := v.(type) {
		case float32:
			v = float64(vt) / math.Pow10(d)
		case float64:
			v = vt / math.Pow10(d)
		case int:
			v = float64(vt) / math.Pow10(d)
		case int8:
			v = float64(vt) / math.Pow10(d)
		case int16:
			v = float64(vt) / math.Pow10(d)
		case int32:
			v = float64(vt) / math.Pow10(d)
		case int64:
			v = float64(vt) / math.Pow10(d)
		case uint:
			v = float64(vt) / math.Pow10(d)
		case uint8:
			v = float64(vt) / math.Pow10(d)
		case uint16:
			v = float64(vt) / math.Pow10(d)
		case uint32:
			v = float64(vt) / math.Pow10(d)
		case uint64:
			v = float64(vt) / math.Pow10(d)
		case []byte:
			vf, _ := strconv.ParseFloat(string(vt), 64)
			v = vf / math.Pow10(d)
		case string:
			vf, _ := strconv.ParseFloat(vt, 64)
			v = vf / math.Pow10(d)
		}
		return v, nil
	}

	if conv == "int" {
		switch vt := v.(type) {
		case float32:
			v = int64(vt)
		case float64:
			v = int64(vt)
		case int:
			v = int64(vt)
		case int8:
			v = int64(vt)
		case int16:
			v = int64(vt)
		case int32:
			v = int64(vt)
		case int64:
			v = vt
		case uint:
			v = int64(vt)
		case uint8:
			v = int64(vt)
		case uint16:
			v = int64(vt)
		case uint32:
			v = int64(vt)
		case uint64:
			v = int64(vt)
		case []byte:
			v, _ = strconv.ParseInt(string(vt), 10, 64)
		case string:
			v, _ = strconv.ParseInt(vt, 10, 64)
		}
		return v, nil
	}

	if conv == "hwaddr" {
		switch vt := v.(type) {
		case string:
			v = net.HardwareAddr(vt).String()
		case []byte:
			v = net.HardwareAddr(vt).String()
		default:
			return nil, fmt.Errorf("invalid type (%T) for hwaddr conversion", v)
		}
		return v, nil
	}

	split := strings.Split(conv, ":")
	if split[0] == "hextoint" && len(split) == 3 {
		endian := split[1]
		bit := split[2]

		bv, ok := v.([]byte)
		if !ok {
			return v, nil
		}

		switch endian {
		case "LittleEndian":
			switch bit {
			case "uint64":
				v = binary.LittleEndian.Uint64(bv)
			case "uint32":
				v = binary.LittleEndian.Uint32(bv)
			case "uint16":
				v = binary.LittleEndian.Uint16(bv)
			default:
				return nil, fmt.Errorf("invalid bit value (%s) for hex to int conversion", bit)
			}
		case "BigEndian":
			switch bit {
			case "uint64":
				v = binary.BigEndian.Uint64(bv)
			case "uint32":
				v = binary.BigEndian.Uint32(bv)
			case "uint16":
				v = binary.BigEndian.Uint16(bv)
			default:
				return nil, fmt.Errorf("invalid bit value (%s) for hex to int conversion", bit)
			}
		default:
			return nil, fmt.Errorf("invalid Endian value (%s) for hex to int conversion", endian)
		}

		return v, nil
	}

	if conv == "ipaddr" {
		var ipbs []byte

		switch vt := v.(type) {
		case string:
			ipbs = []byte(vt)
		case []byte:
			ipbs = vt
		default:
			return nil, fmt.Errorf("invalid type (%T) for ipaddr conversion", v)
		}

		switch len(ipbs) {
		case 4, 16:
			v = net.IP(ipbs).String()
		default:
			return nil, fmt.Errorf("invalid length (%d) for ipaddr conversion", len(ipbs))
		}

		return v, nil
	}

	return nil, fmt.Errorf("invalid conversion type '%s'", conv)
}