Getting connection refused when invoking a service using Java SDK DaprClient

[SharAkshay]

I have two services running in docker container under same network with their respective dapr sidecars which are also part of same docker network. Now I am trying to invoke serviceB endpoint from serviceA using dapr client like this

daprClient.invokeMethod(appId, methodEndpoint, payload, HttpExtension.POST, Response.class);

When I do so I get below exception
Error invoking Service B: java.net.ConnectException
reactor.core.Exceptions$ReactiveException: java.net.ConnectException
at reactor.core.Exceptions.propagate(Exceptions.java:408) ~[reactor-core-3.5.10.jar!/:3.5.10]
at reactor.core.publisher.BlockingSingleSubscriber.blockingGet(BlockingSingleSubscriber.java:101) ~[reactor-core-3.5.10.jar!/:3.5.10]

Could you help me with this issue?

Please consider below points

1. Both my services (ServiceA and ServiceB) are up and running as I have checked the healthchecks and it shows status up.
2. I can invoke serviceB via it's repective dapr sidecar URL
3. I can invoke serviceA also via it's repective dapr sidecar URL
4. I have curl the serviceB endpoint via it's dapr sidecar from inside of the serviceA cdocker container so that connectivity works

I can see the dapr sidecar container logs as well and it has discovered the respective services so all looks good over there also.

[patelsan]

Based on what you’ve described, the two things I’d check first are:

Is your DaprClient actually talking HTTP on port 3500?
By default the Java SDK will open a gRPC channel on port 50001 unless you explicitly tell it to use HTTP. If you’re invoking with HttpExtension.POST but never called

DaprClient client = new DaprClientBuilder()
  .withPort(3500, HttpExtension.HTTP)   // <- explicit HTTP port
  .build();

it may still be dialing 50001 under the covers. That mismatch will immediately throw a ConnectException.

Are you formatting your method name exactly as the sidecar expects?
In most examples the endpoint is prefixed with a slash—e.g.

String methodEndpoint = "/doWork";

Let me know if this helps.

[WhitWaldo]

I'm going to move this to the Java SDK repository as it's not necessarily an issue with the runtime.

[SharAkshay]

@patelsan There is no method as withPort in DaprClientBuilder(). Is there any other other way to specify it?

[artur-ciocanu]

@SharAkshay here is an example on how you can override the port: https://github.com/dapr/java-sdk/blob/master/dapr-spring/dapr-spring-boot-autoconfigure/src/main/java/io/dapr/spring/boot/autoconfigure/client/DaprClientAutoConfiguration.java#L62. This is part of Spring Boot integration, but you can use the same approach in your application.

[siri-varma]

@SharAkshay Closing this issue because of inactivity. If you still have questions please feel free to reach out/reopen the issue. Thank you.