KafkaMessageBus v0.2.0 KafkaMessageBus.Consumer View Source
Link to this section Summary
Functions
Invoked for each message set consumed from a Kafka topic partition
Invoked when the server is started. start_link/5
will block until it
returns
Link to this section Functions
Invoked by KafkaEx.GenConsumer.call/3
.
Note the default implementation will cause a MatchError
. If you want to
interact with your consumer, you must implement a handle_call function.
Callback implementation for KafkaEx.GenConsumer.handle_call/3
.
Invoked for each message set consumed from a Kafka topic partition.
message_set
is a message set fetched from a Kafka broker and state
is the
current state of the KafkaEx.GenConsumer
.
Returning {:async_commit, new_state}
acknowledges message
and continues
to consume from the Kafka queue with new state new_state
. Acknowledged
messages will be auto-committed (possibly at a later time) based on the
:commit_interval
and :commit_threshold
options.
Returning {:sync_commit, new_state}
commits message
synchronously before
continuing to consume from the Kafka queue with new state new_state
.
Committing a message synchronously means that no more messages will be
consumed until the message’s offset is committed. :sync_commit
should be
used sparingly, since committing every message synchronously would impact a
consumer’s performance and could result in excessive network traffic.
Callback implementation for KafkaEx.GenConsumer.handle_message_set/2
.
Invoked when the server is started. start_link/5
will block until it
returns.
topic
and partition
are the arguments passed to start_link/5
. They
identify the Kafka partition that the KafkaEx.GenConsumer
will consume from.
Returning {:ok, state}
will cause start_link/5
to return {:ok, pid}
and
the process to start consuming from its assigned partition. state
becomes
the consumer’s state.
Any other return value will cause the start_link/5
to return {:error,
error}
and the process to exit.
Callback implementation for KafkaEx.GenConsumer.init/2
.