Message Format

Message Format

    /**
     * 1. 4 byte CRC32 of the message
     * 2. 1 byte "magic" identifier to allow format changes, value is 0 or 1
     * 3. 1 byte "attributes" identifier to allow annotations on the message independent of the version
     *    bit 0 ~ 2 : Compression codec.
     *      0 : no compression
     *      1 : gzip
     *      2 : snappy
     *      3 : lz4
     *    bit 3 : Timestamp type
     *      0 : create time
     *      1 : log append time
     *    bit 4 ~ 7 : reserved
     * 4. (Optional) 8 byte timestamp only if "magic" identifier is greater than 0
     * 5. 4 byte key length, containing length K
     * 6. K byte key
     * 7. 4 byte payload length, containing length V
     * 8. V byte payload
     */