ScalaConsultants / zio-akka-quickstart.g8

zio-akka-quickstart

A Giter8 template for a fully functional, ready to deploy microservice (or monolith - it's up to you).

This template integrates ZIO with Akka HTTP and Slick, so that you can seamlessly use all the power of ZIO in a familiar environment of battle tested Akka HTTP routes and Slick query DSL. Out of the box there's a set of REST endpoints for example CRUD operations ready to refactor.

Other notable integrations include:

• (Optional) GraphQL endpoint with GraphQL console
• (Optional) WebSocket endpoint
• (Optional) SSE endpoint
• Testcontainers for integration tests
• Flyway migrations
• sbt-native-packager for docker images
• scalafmt
• play-json for JSON processing.
• zio-logging for logging.
• zio-config for typesafe configuration.
• zio-test for testing.

Setting up the project

sbt new ScalaConsultants/zio-akka-quickstart.g8
# then follow interactive process to choose project name and other parameters

Run tests

cd <project-name>
sbt test

Launch and interact

sbt run

# create an item
curl --request POST \
  --url http://localhost:8080/items \
  --header 'content-type: application/json' \
  --data '{
	"name":"BigMac",
	"price": 10.0
}'

# get all items
curl --request GET \
  --url http://localhost:8080/items

Check out more routes in Api.scala

Docker image

Template provides packaging as docker image out of the box, using sbt-native-packager plugin.

To create an image, run:

sbt docker:publishLocal

This will create a docker image locally, named the same as your project is. You can run it like the following:

docker run -d -p 8080:8080 --name=<project_name> <project_name>:0.1.0-SNAPSHOT

Main components

This sample app has several key components:

• ItemRepository, which is quite a regular slick repo, with the only twist - it works with ZIO and not Futures. Backed up by an H2 database and Hikari connection pool.
• Api - pretty standard akka-http CRUD endpoint, also powered by ZIO.
• interop - package, where all the integration magic is happening.
• ApplicationService - a more higher level service, that works with different error type and uses ZIO environment.
• Boot - wiring all the components together using ZLayer.
• ApiSpec - akka-http endpoint spec using zio-test.

GraphQL

During initialization step, there is a possibility to add GraphQL endpoint managed by Caliban library. It adds two endpoints to the api: /api/graphql which is responsible for GraphQL queries and /graphiql with simple GraphiQL console to play with the API.

To try out this feature open the browser http://localhost:8080/graphiql

What in the world is ZLayer?

If you're new to ZIO you might be confused about what's happening in Boot.scala and what is ZLayer, please check out ebook about this subject Mastering ZLayer as well as the latest official documentation.

Template license

Written in 2020 by Scalac Sp. z o.o.

To the extent possible under law, the author(s) have dedicated all copyright and related and neighboring rights to this template to the public domain worldwide. This template is distributed without any warranty. See http://creativecommons.org/publicdomain/zero/1.0/.