Il lun 22 lug 2019, 17:27 Enrico Olivelli <eolive...@gmail.com> ha scritto:
> Great, thank you Matteo and Sijie, > last question....from org.apache.pulsar.client.api.Reader interface...is > there any way to get the internal subscription id. > > I guess I should perform the following steps: > 1) creare a Reader > 2) get subscription id > 3) move the reader to my current message id > 4) use Admin API ( > admin.topics().getStats(tenantId).subscriptions.get(subscriptionId).msgBacklog) > > > for 2) I am trying to go into ReaderImpl.... > ReaderImpl reader = (ReaderImpl) pulsarReader; > ConsumerImp consumer = reader.getConsumer(); > .... > > but I see no easy (and future proff) way > Am I missing some part of the story? Enrico > > > > Enrico > > > Il giorno lun 22 lug 2019 alle ore 16:59 Matteo Merli < > matteo.me...@gmail.com> ha scritto: > >> The reader has indeed already a "dummy" ephemeral subscription. As >> long as it's connected, the backlog for the reader is reported. >> >> >> -- >> Matteo Merli >> <matteo.me...@gmail.com> >> >> On Mon, Jul 22, 2019 at 7:26 AM Enrico Olivelli <eolive...@gmail.com> >> wrote: >> > >> > Sijie, >> > >> > Il lun 22 lug 2019, 15:50 Sijie Guo <guosi...@gmail.com> ha scritto: >> >> >> >> You can query the topic stats. There is a "backlog" field in topic >> stats. It will tell you how many messages that a subscription has not >> consumed. It is similar as consumer lag in Kafka. >> > >> > >> > Actually I don't have a subscription to the topic as I am using the >> Reader API. >> > should I create a dummy subscription ? I image this would have a cost. >> > >> > I would use this feature for monitoring and I would like not to spend >> much resources >> > >> > Enrico >> > >> >> >> >> Thanks, >> >> Sijie >> >> >> >> On Mon, Jul 22, 2019 at 6:46 PM Enrico Olivelli <eolive...@gmail.com> >> wrote: >> >>> >> >>> Hello, >> >>> >> >>> I am looking for a function in Pulsar API to get the current consumer >> "lag" >> >>> >> >>> I see that Pulsar recently added getLastMessageId API but this is not >> useful to me >> >>> https://pulsar.apache.org/admin-rest-api/#operation/getLastMessageId >> >>> >> >>> In Pulsar if you have two message ids you cannot compute any kind of >> "distance". >> >>> >> >>> I am migrating from Kafka and in Kafka the message id is an >> incremental number (per partition). >> >>> >> >>> I am using the Reader API, and I am storing the last processed >> messageId in an external system, this way I have full control over the >> portion of the stream that I am processing. >> >>> >> >>> I think Sijie or Jia already told me something about this topic but I >> can't find references >> >>> >> >>> Thanks in advance >> >>> >> >>> Enrico >> >>> >> >>> >> >
