Consumes messages from \p topic and \p partition, calling the provided callback for each consumed messsage.
\p consumeCallback() provides higher throughput performance than \p consume().
\p timeout_ms is the maximum amount of time to wait for one or more messages to arrive.
The provided \p consume_cb instance has its \p consume_cb function called for every message received.
The \p opaque argument is passed to the \p consume_cb as \p opaque.
the number of messages processed or -1 on error.
Consumer::consume()
See Implementation
Consumes messages from \p topic and \p partition, calling the provided callback for each consumed messsage.
\p consumeCallback() provides higher throughput performance than \p consume().
\p timeout_ms is the maximum amount of time to wait for one or more messages to arrive.
The provided \p consume_cb instance has its \p consume_cb function called for every message received.
The \p opaque argument is passed to the \p consume_cb as \p opaque.
the number of messages processed or -1 on error.