Steps to setup from scratch
1) Create sbt build file "build.sbt"
2) Create plugins file project/plugins.sbt
3) Create build properties file project/build.properties
4) Run sbt command from project root to generate project directories, generated projects at target/lagom-dynamic-projects
Service Locator project: lagom-internal-meta-project-service-locator
cassandra project: lagom-internal-meta-project-cassandra
5) Create folders in all projects to follow maven like directory structure layout for project source code: src/main/java and src/main/java/resources and test folders.
6) Weather microservice
a) WeatherService Interface with method:
weatherStatsForToday()
b) WeatherServiceImpl to return weatherstats from a random list of weather stats
7) Greeting Microservice
GreetingService Interface:
handleGreetFrom(String user)
a) Reply back to user with greeting message("Hello") along with weather stats fetched from weather microservice
b) Update the greeting message("Hello Again") for an existing user.
8) GreetingEntity: PersistentEntity<GreetingCommand, GreetingEvent, GreetingState>
a) handles ReceivedGreetingCommand
b) Stores ReceivedGreetingEvent events to cassandra
c) Processes ReceivedGreetingEvent to update GreetingState("Hello" to "Hello Again") if required.
9) Register modules with lagom using application.conf files.
10) Run project: sbt lagom:runAll
Sample Run:
curl http://localhost:9000/api/greeting/Nikhil;
Hello Nikhil! Today's weather stats: Going to be very humid, Take Water
curl http://localhost:9000/api/greeting/Nikhil;
Hello Again Nikhil! Today's weather stats: Going to Rain, Take Umbrella
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