Duplicate Messages due to Unkn Fields

[val123456]

Just got a new Neptune R900 water meter, and am integrating it into my monitoring solution. I use the -unique=true flag but noticed what looked like duplicate messages. It appears unique means all fields match AND it only compares to the last message. However, my meter flops the Unkn1 field . . . sample below.

"Message":{"ID":1563476986,"Unkn1":163,"NoUse":35,"BackFlow":0,"Consumption":57171,"Unkn3":0,"Leak":1,"LeakNow":0}}
"Message":{"ID":1563476986,"Unkn1":131,"NoUse":35,"BackFlow":0,"Consumption":57171,"Unkn3":0,"Leak":1,"LeakNow":0}}
"Message":{"ID":1563476986,"Unkn1":163,"NoUse":35,"BackFlow":0,"Consumption":57171,"Unkn3":0,"Leak":1,"LeakNow":0}}
"Message":{"ID":1563476986,"Unkn1":131,"NoUse":35,"BackFlow":0,"Consumption":57171,"Unkn3":0,"Leak":1,"LeakNow":0}}
"Message":{"ID":1563476986,"Unkn1":163,"NoUse":35,"BackFlow":0,"Consumption":57171,"Unkn3":0,"Leak":1,"LeakNow":0}}

Would it may sense to only match the known fields???

type R900 struct {
    ID          uint32 `xml:",attr"` // 32 bits
    Unkn1       uint8  `xml:",attr"` // 8 bits
    NoUse       uint8  `xml:",attr"` // 6 bits, day bins of no use
    BackFlow    uint8  `xml:",attr"` // 2 bits, backflow past 35d hi/lo
    Consumption uint32 `xml:",attr"` // 24 bits
    Unkn3       uint8  `xml:",attr"` // 2 bits
    Leak        uint8  `xml:",attr"` // 4 bits, day bins of leak
    LeakNow     uint8  `xml:",attr"` // 2 bits, leak past 24h hi/lo
    checksum    [5]byte
}

[bemasher]

The issue is likely that determining a message is unique currently requires the checksum, which in most cases would be different if any of the unknown fields are changed. I would recommend writing your own mechanism in your collection system to ignore messages you don't want.