sample: add counter using ReplicatedEntity

.circleci/config.yml

@@ -168,7 +168,13 @@ jobs:
           command: |
             cd samples/valueentity-counter
             echo "Running mvn with SDK version: '$SDK_VERSION'"
-            mvn -Dakkaserverless-sdk.version=$SDK_VERSION verify -Pit            
+            mvn -Dakkaserverless-sdk.version=$SDK_VERSION verify -Pit
+      - run:
+          name: Run integration tests for Counter Replicated Entity sample
+          command: |
+            cd samples/replicatedentity-counter
+            echo "Running mvn with SDK version: '$SDK_VERSION'"
+            mvn -Dakkaserverless-sdk.version=$SDK_VERSION verify -Pit
       - save_sbt_cache
 
   publish:

.gitignore

@@ -39,3 +39,4 @@ src_managed
 storage
 tags
 target
+dependency-reduced-pom.xml

samples/replicatedentity-counter/README.md

@@ -0,0 +1,78 @@
+# Implementing a Counter as a Replicated Entity
+
+## Building and running unit tests
+
+To compile and test the code from the command line, use
+
+```shell
+mvn verify
+```
+
+## Running the integration tests
+
+The integration test sources are in the `src/it/java` directory.
+
+NOTE: As this is not part of the standard Maven setup, you might need to add it as test source directory in your IDE. (IntelliJ: right klick on the directory -> "Mark directory as" | "Test sources root")
+
+Maven is configured to run tests from it when using the `it` profile.
+
+```shell
+mvn verify -Pit
+```
+
+The integration test uses Docker via [TestContainers](https://www.testcontainers.org/) to set up the Akka Serverless environment before calling the gRPC API.
+
+## Running Locally
+
+In order to run your application locally, you must run the Akka Serverless proxy. The included `docker compose` file contains the configuration required to run the proxy for a locally running application.
+It also contains the configuration to start a local Google Pub/Sub emulator that the Akka Serverless proxy will connect to.
+To start the proxy, run the following command from this directory:
+
+
+```shell
+docker compose up
+```
+
+> On Linux this requires Docker 20.10 or later (https://github.com/moby/moby/pull/40007),
+> or for a `USER_FUNCTION_HOST` environment variable to be set manually.
+
+```shell
+docker compose -f docker-compose.yml -f docker-compose.linux.yml up
+```
+
+To start the application locally, the `exec-maven-plugin` is used. Use the following command:
+
+```shell
+mvn compile exec:java
+```
+
+For further details see [Running a service locally](https://developer.lightbend.com/docs/akka-serverless/developing/running-service-locally.html) in the documentation.
+
+## Exercise the service
+
+With both the proxy and your application running, any defined endpoints should be available at `http://localhost:9000`. In addition to the defined gRPC interface, each method has a corresponding HTTP endpoint. Unless configured otherwise (see [Transcoding HTTP](https://developer.lightbend.com/docs/akka-serverless/java/proto.html#_transcoding_http)), this endpoint accepts POST requests at the path `/[package].[entity name]/[method]`. For example, using `curl`:
+
+```shell
+curl -XPOST -H "Content-Type: application/json" localhost:9000/com.example.CounterService/GetCurrentCounter -d '{"counterId": "foo"}'
+```
+
+Or, given [`grpcurl`](https://github.com/fullstorydev/grpcurl):
+
+```shell
+grpcurl -plaintext -d '{"counterId": "foo"}' localhost:9000 com.example.CounterService/GetCurrentCounter 
+```
+
+## Deploying
+
+To deploy your service, install the `akkasls` CLI as documented in
+[Setting up a local development environment](https://developer.lightbend.com/docs/akka-serverless/getting-started/set-up-development-env.html)
+and configure a Docker Registry to upload your docker image to.
+
+You will need to update the `dockerImage` property in the `pom.xml` and refer to
+[Configuring registries](https://developer.lightbend.com/docs/akka-serverless/deploying/registries.html)
+for more information on how to make your docker image available to Akka Serverless.
+
+Finally, you can use the [Akka Serverless Console](https://console.akkaserverless.com)
+to create an Akka Serverless project and then deploy your service into it either by using `mvn deploy`,
+through the `akkasls` CLI or via the web interface. When using `mvn deploy`, Maven will also
+conveniently package and publish your docker image prior to deployment.

samples/replicatedentity-counter/docker-compose.linux.yml

@@ -0,0 +1,5 @@
+version: "3"
+services:
+  akka-serverless-proxy:
+    extra_hosts:
+      - "host.docker.internal:host-gateway"

samples/replicatedentity-counter/docker-compose.yml

@@ -0,0 +1,15 @@
+version: "3"
+services:
+  akka-serverless-proxy:
+    image: gcr.io/akkaserverless-public/akkaserverless-proxy:0.7.0-beta.9
+    command: -Dconfig.resource=dev-mode.conf -Dakkaserverless.proxy.eventing.support=google-pubsub-emulator
+    ports:
+      - "9000:9000"
+    environment:
+      USER_FUNCTION_HOST: ${USER_FUNCTION_HOST:-host.docker.internal}
+      USER_FUNCTION_PORT: ${USER_FUNCTION_PORT:-8080}
+  gcloud-pubsub-emulator:
+    image: gcr.io/google.com/cloudsdktool/cloud-sdk:341.0.0
+    command: gcloud beta emulators pubsub start --project=test --host-port=0.0.0.0:8085
+    ports:
+      - 8085:8085