add: app readme

Author: zhenik

example/readme.md

@@ -0,0 +1,27 @@
+## Application example
+
+RESTapi service.
+
+### Tech stack
+
+* [Akka (actor, http, stream)](https://akka.io/)
+* [Consul-client java](https://github.com/rickfast/consul-client)
+* [Shade plugin](https://maven.apache.org/plugins/maven-shade-plugin/) for fat-jar
+* Java 8
+* Docker
+
+### REST
+
+| REQUEST             | RESPONSE            | 
+| -------------       |:-------------:      | 
+| GET /health         | 200 OK and app-id   | 
+| POST /app           | 200 OK              | 
+
+
+### Notes
+
+Pay attention to config file `application.conf`, it is loaded by [typesafe config](https://github.com/lightbend/config).
+
+`DiscoveryAgentActor` responsible for registration this app instance in consul and send each (10 sec default) health check to consul.
+
+

example/src/main/java/ru/zhenik/akka/example/infrastructure/discovery/DiscoveryAgentActor.java

@@ -76,6 +76,7 @@ public Receive createReceive() {
               // send each (10seconds default) health-check to consul
               .scheduler()
               .schedule(
+                  // delay before 1st request
                   new FiniteDuration(5, TimeUnit.SECONDS),
                   SCHEDULED_WORK_DELAY,
                   healthCheck(),