49 lines
1.8 KiB
Markdown
49 lines
1.8 KiB
Markdown
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## Lagom
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This module contains articles about the Lagom framework.
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### Relevant articles
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- [Guide to Reactive Microservices Using Lagom Framework](https://www.baeldung.com/lagom-reactive-microservices)
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### Steps to setup from scratch
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1) Create sbt build file "build.sbt"
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2) Create plugins file project/plugins.sbt
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3) Create build properties file project/build.properties
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4) Run sbt command from project root to generate project directories, generated projects at target/lagom-dynamic-projects
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Service Locator project: lagom-internal-meta-project-service-locator
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cassandra project: lagom-internal-meta-project-cassandra
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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.
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6) Weather microservice
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a) WeatherService Interface with method:
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weatherStatsForToday()
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b) WeatherServiceImpl to return weatherstats from a random list of weather stats
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7) Greeting Microservice
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GreetingService Interface:
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handleGreetFrom(String user)
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a) Reply back to user with greeting message("Hello") along with weather stats fetched from weather microservice
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b) Update the greeting message("Hello Again") for an existing user.
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8) GreetingEntity: PersistentEntity<GreetingCommand, GreetingEvent, GreetingState>
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a) handles ReceivedGreetingCommand
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b) Stores ReceivedGreetingEvent events to cassandra
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c) Processes ReceivedGreetingEvent to update GreetingState("Hello" to "Hello Again") if required.
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9) Register modules with lagom using application.conf files.
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10) Run project: sbt lagom:runAll
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### Sample Run:
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```
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$ curl http://localhost:9000/api/greeting/Nikhil;
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Hello Nikhil! Today's weather stats: Going to be very humid, Take Water
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$ curl http://localhost:9000/api/greeting/Nikhil;
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Hello Again Nikhil! Today's weather stats: Going to Rain, Take Umbrella
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```
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