eventStreammethod in the
persistentEntityRegistry. That produces a
Sourceof all the events, though, at most you can filter by tag, but you can’t filter by persistent ID. Also, note that each client of an
eventStreamcreates one or many polling instances on your database so it is not good to invoke
eventStreamin a unbounded fashion. Use sparingly.
Sharding can be done in two ways, either manually by returning different tags based on information in the event, or automatically by returning a AggregateEventShards tag, which will tell Lagom to shard the tag used based on the entity’s persistence ID. It’s important to ensure all the events for the same entity end up with the same tag (and hence in the same shard), otherwise, event processing for that entity may be out of order, since the read side nodes will consume the event streams for their tags at different paces.
hi, i am looking for some advice, i am building a schema denormaliser. normalized data in mysql and denormalized will be in a NoSQL server
based on my experience i know with the following approach i will be likely to achieve the outcome
i feel this maybe a common problem that already have other solutions, can anyone give some advice? like do i need kafka-streams? do i need the schema-registry?
By default the Service Gateway binds to
localhost. It is possible to change that address by adding this to your build.
lagomServiceGatewayAddress in ThisBuild := "0.0.0.0"
Hi! I´ve updated my developement environment from Lagom 1.4.9 to 1.6.1 (i do not need the data in the db.. just the code update)... Now when i deploy the 1.6.1 based version i can see that akka discovery wants the discovery method to be defined. For 1.4.9 i used a eureka service locator for service discovery. How does this fit into akka-discovery?
from my understanding, there are 2 types of discovery procedures: lagom service discovery and akka cluster discovery, and that the most easy way would be to use the "AkkaDiscoveryServiceLocator" for lagom also - is this correct?
One additional Question: Currently we're using spring cloud-gateway in the constellation: internet <-> nginx <-> sping-cloud-gw <-> lagom-services
Spring-cloud gatway does the discovery via eureka.
=> What do you use instead of the cloud-gateway to route requests to the correct service?
LagomClientFactory. See the
web-gatewayat https://github.com/lagom/online-auction-scala/ for example...
pathto a service and then a way to locate a running instance of that service. I`m not familiar with the SoA on that set of tools.
Service.Descriptoris not a rest api service definition. Interllay it is implemented to transport the information as JSON-serialized messages over HTTP but that’s just coincidental. Having said that, the only place where you can describe a Topic is in the
Service.Descriptorso, even if all your strict and streamed calls are implemented in gRPC, you still need the
Service.Descriptor. Actually, for a Lagom service to be runnable you mist provide a
Service.Descriptorwith at least a
nameso you can’t work around from that.