Make `(msg *Message) totalSize()` public

[taguhoiya]

Suggestion

• I would like to make totalSize() public to get to know the exact size of kakfa.Message
  • now the method of knowing the message size is the package-private one and too complicated to implement on the client side.
  • (I actually used totalSize() in my repository and had to copy and paste many methods all the way)

can we make totalSize() public?

reference

here are all the methods that I personally implemented and I copied and pasted all methods literally from the https://github.com/segmentio/kafka-go/blob/main/message.go

source code

```golang package kafkas import ( "github.com/segmentio/kafka-go" ) // This file is all implemented by https://github.com/segmentio/kafka-go/blob/main/message.go const timestampSize = 8 func varIntLen(i int64) int { u := uint64((i << 1) ^ (i >> 63)) // zig-zag encoding n := 0 for u >= 0x80 { u >>= 7 n++ } return n + 1 } func varBytesLen(b []byte) int { return varIntLen(int64(len(b))) + len(b) } func varStringLen(s string) int { return varIntLen(int64(len(s))) + len(s) } func varArrayLen(n int, f func(int) int) int { size := varIntLen(int64(n)) for i := 0; i < n; i++ { size += f(i) } return size } func sizeofBytes(b []byte) int32 { return 4 + int32(len(b)) } func size(msg *kafka.Message) int32 { return 4 + 1 + 1 + sizeofBytes(msg.Key) + sizeofBytes(msg.Value) + timestampSize } func headerSize(msg *kafka.Message) int { return varArrayLen(len(msg.Headers), func(i int) int { h := &msg.Headers[i] return varStringLen(h.Key) + varBytesLen(h.Value) }) } // Make it public for external packages func TotalSize(msg *kafka.Message) int32 { return int32(headerSize(msg)) + size(msg) } ```