Understood. So if we want it to start consuming from earliest we should add props.put(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest");
So when we start the app first time it will start from earliest. Later when we stop this app and restart it will start from point where we has last committed offset,. (No need to comment this line then and then restart.) Hence earliest (or latest) offset is used only when no offsets are found for that consumer group. Thanks Sachin On Wed, Dec 28, 2016 at 3:02 PM, Matthias J. Sax <matth...@confluent.io> wrote: > Hi Sachin, > > What do you mean by "with this commented"? Did you set auto.offset.reset > to "earliest" or not? Default value is "latest" and if you do not set it > to "earliest", that the application will start consuming from > end-of-topic if no committed offsets are found. > > For default values of Kafka Streams parameters see > http://docs.confluent.io/3.0.1/streams/developer-guide. > html#configuring-a-kafka-streams-application > > For default consumer parameters see > http://kafka.apache.org/0100/documentation.html#newconsumerconfigs > > > -Matthias > > > On 12/27/16 3:27 PM, Sachin Mittal wrote: > > Hi, > > I started my new streams app with this commented > > //props.put(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest"); > > > > What I observed was that it started consuming message from latest offset > > from the source topic. > > Based on comments by Eno I thought that if offset do not exist then > > > > So in practice an app will include the property below (e.g., set to > > "earliest") > > > > However it picked the latest offset. Also I check this props > > auto.offset.reset in the latest doc and I see it as largest. > > > > So now I am confused that in streams application what is the default > offset > > if none exist? > > > > note I am using version kafka_2.10-0.10.0.1. > > > > Thanks > > Sachin > > > > > > > > On Mon, Nov 21, 2016 at 7:08 PM, Eno Thereska <eno.there...@gmail.com> > > wrote: > > > >> Hi Sachin, > >> > >> There is no need to check within the app whether the offset exists or > not, > >> since the consumer code will do that check automatically for you. So in > >> practice an app will include the property below (e.g., set to > "earliest"), > >> but that will only have an effect if the consumer detects that the > offsets > >> do not exist anymore. If the offset exist, then that line is a noop. > >> > >> So in summary, I'd just include that property, and no more code changes > >> are required. > >> > >> Thanks > >> Eno > >> > >>> On 21 Nov 2016, at 12:11, Sachin Mittal <sjmit...@gmail.com> wrote: > >>> > >>> So in my java code how can I check > >>> when there is no initial offset in Kafka or if the current offset does > >> not > >>> exist any more on the server (e.g. because that data has been deleted) > >>> > >>> So in this case as you have said I can set offset as > >>> props.put(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest"); //or > >> latest > >>> > >>> Thanks > >>> Sachin > >>> > >>> > >>> On Mon, Nov 21, 2016 at 4:16 PM, Eno Thereska <eno.there...@gmail.com > >> <mailto:eno.there...@gmail.com>> > >>> wrote: > >>> > >>>> Hi Sachin, > >>>> > >>>> Currently you can only change the following global configuration by > >> using > >>>> "earliest" or "latest", as shown in the code snippet below. As the > >> Javadoc > >>>> mentions: "What to do when there is no initial offset in Kafka or if > the > >>>> current offset does not exist any more on the server (e.g. because > that > >>>> data has been deleted)": > >>>> > >>>> ... > >>>> props.put(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest"); > >>>> ... > >>>> return new KafkaStreams(builder, props) > >>>> > >>>> > >>>> > >>>> In addition, there is a tool to reset the offsets of all topics to the > >>>> beginning. This is useful for reprocessing: > >> https://www.confluent.io/blog/ > >>>> data-reprocessing-with-kafka-streams-resetting-a-streams-application/ > < > >>>> https://www.confluent.io/blog/data-reprocessing-with- < > >> https://www.confluent.io/blog/data-reprocessing-with-> > >>>> kafka-streams-resetting-a-streams-application/> > >>>> > >>>> However, there is no option currently for resetting the offset to an > >>>> arbitrary offset. > >>>> > >>>> Thanks > >>>> Eno > >>>> > >>>>> On 21 Nov 2016, at 10:37, Sachin Mittal <sjmit...@gmail.com> wrote: > >>>>> > >>>>> Hi > >>>>> I am running a streaming application with > >>>>> streamsProps.put(StreamsConfig.APPLICATION_ID_CONFIG, "test"); > >>>>> > >>>>> How do I find out the offsets for each of the source, intermediate > and > >>>>> internal topics associated with this application. > >>>>> > >>>>> And how can I reset them to some specific value via shell of > otherwise. > >>>>> > >>>>> Thanks > >>>>> Sachin > >> > >> > > > >
