feat(server): Implement health check endpoint (#3)

.gitignore

@@ -3,5 +3,8 @@ target/
 .idea/
 
 project/target
+project/project
 
 modules/foundations/target
+
+modules/server/target

.scalafmt.conf

@@ -3,10 +3,9 @@ maxColumn = 80
 project.git = true
 runner.dialect = scala3
 rewrite.scala3.convertToNewSyntax = true
+rewrite.scala3.removeOptionalBraces = yes
 rewrite.rules = [RedundantBraces]
 align.preset = most
 align.multiline = false
 align.stripMargin = true
-project.excludePaths = ["glob:**/project/"]
 rewrite.scala3.insertEndMarkerMinLines = 1
-

build.sbt

@@ -3,8 +3,11 @@ import BuildHelper.*
 lazy val foundations = (project in file("modules/foundations"))
   .settings(libraryDependencies ++= Dependencies.dependencies)
 
+lazy val server = (project in file("modules/server"))
+  .settings(libraryDependencies ++= Dependencies.dependencies)
+
 lazy val root = (project in file("."))
   .settings(standardSettings)
   .settings(nameSettings)
-  .aggregate(foundations)
-  .dependsOn(foundations)
+  .aggregate(foundations, server)
+  .dependsOn(foundations, server)

modules/server/src/main/scala/io/kevchuang/reviewboard/Application.scala

@@ -0,0 +1,21 @@
+package io.kevchuang.reviewboard
+
+import io.kevchuang.reviewboard.http.controllers.HealthController
+import io.kevchuang.reviewboard.http.server.{HttpServer, HttpServerLive}
+import zio.*
+import zio.http.Server
+
+object Application extends ZIOAppDefault:
+
+  private val program: ZIO[HttpServer & Server, Throwable, Unit] =
+    for
+      health   <- HealthController.make
+      endpoints = List(health.healthCheck)
+      _        <- HttpServer.start(endpoints)
+    yield ()
+
+  override def run: ZIO[Any with ZIOAppArgs with Scope, Any, Any] =
+    program
+      .provide(Server.default, HttpServerLive.live)
+
+end Application

modules/server/src/main/scala/io/kevchuang/reviewboard/domain/health.scala

@@ -0,0 +1,13 @@
+package io.kevchuang.reviewboard.domain
+
+import zio.json.*
+import io.github.iltotore.iron.*
+import io.github.iltotore.iron.zioJson.given
+import io.kevchuang.reviewboard.types.NotEmpty
+
+object health:
+  final case class HealthCheckResponse(response: String :| NotEmpty)
+  object HealthCheckResponse:
+    given JsonCodec[HealthCheckResponse] = DeriveJsonCodec.gen
+  end HealthCheckResponse
+end health

modules/server/src/main/scala/io/kevchuang/reviewboard/http/controllers/HealthController.scala

@@ -0,0 +1,18 @@
+package io.kevchuang.reviewboard.http.controllers
+
+import io.kevchuang.reviewboard.domain.health.HealthCheckResponse
+import io.kevchuang.reviewboard.http.endpoints.HealthEndpoint
+import zio.*
+import io.github.iltotore.iron.*
+import sttp.tapir.server.ServerEndpoint
+
+class HealthController private extends HealthEndpoint:
+  def healthCheck: ServerEndpoint[Any, Task] =
+    healthEndpoint.serverLogicSuccess[Task](_ =>
+      ZIO.succeed(HealthCheckResponse("All good !"))
+    )
+end HealthController
+
+object HealthController:
+  def make: UIO[HealthController] = ZIO.succeed(new HealthController)
+end HealthController

modules/server/src/main/scala/io/kevchuang/reviewboard/http/endpoints/HealthEndpoint.scala

@@ -0,0 +1,19 @@
+package io.kevchuang.reviewboard.http.endpoints
+
+import io.kevchuang.reviewboard.domain.health.*
+import io.kevchuang.reviewboard.domain.health.HealthCheckResponse.given
+import sttp.tapir.*
+import sttp.tapir.codec.iron.{*, given}
+import sttp.tapir.generic.auto.*
+import sttp.tapir.json.zio.{*, given}
+
+trait HealthEndpoint:
+  val healthEndpoint: ApiEndpoint[Unit, Unit, HealthCheckResponse] =
+    endpoint
+      .tag("health")
+      .name("health")
+      .description("health check")
+      .get
+      .in("health")
+      .out(jsonBody[HealthCheckResponse])
+end HealthEndpoint

modules/server/src/main/scala/io/kevchuang/reviewboard/http/endpoints/package.scala

@@ -0,0 +1,7 @@
+package io.kevchuang.reviewboard.http
+
+import sttp.tapir.PublicEndpoint
+
+package object endpoints:
+  type ApiEndpoint[I, E, O] = PublicEndpoint[I, E, O, Any]
+end endpoints

modules/server/src/main/scala/io/kevchuang/reviewboard/http/server/HttpServer.scala

@@ -0,0 +1,18 @@
+package io.kevchuang.reviewboard.http.server
+
+import sttp.tapir.server.ServerEndpoint
+import zio.*
+import zio.http.Server
+
+trait HttpServer:
+  def start(
+      endpoints: List[ServerEndpoint[Any, Task]]
+  ): ZIO[Server, Throwable, Unit]
+end HttpServer
+
+object HttpServer:
+  def start(
+      endpoints: List[ServerEndpoint[Any, Task]]
+  ): ZIO[HttpServer & Server, Throwable, Unit] =
+    ZIO.serviceWithZIO[HttpServer](_.start(endpoints))
+end HttpServer

modules/server/src/main/scala/io/kevchuang/reviewboard/http/server/HttpServerLive.scala

@@ -0,0 +1,22 @@
+package io.kevchuang.reviewboard.http.server
+
+import sttp.tapir.server.ServerEndpoint
+import sttp.tapir.server.ziohttp.{ZioHttpInterpreter, ZioHttpServerOptions}
+import zio.*
+import zio.http.Server
+
+object HttpServerLive:
+  def live: ZLayer[Any, Nothing, HttpServer] =
+    ZLayer.succeed(
+      new HttpServer:
+        override def start(
+            endpoints: List[ServerEndpoint[Any, Task]]
+        ): ZIO[Server, Throwable, Unit] =
+          Server
+            .serve(
+              ZioHttpInterpreter(
+                ZioHttpServerOptions.default
+              ).toHttp(endpoints)
+            )
+    )
+end HttpServerLive

modules/server/src/main/scala/io/kevchuang/reviewboard/types/package.scala

@@ -0,0 +1,7 @@
+package io.kevchuang.reviewboard
+
+import io.github.iltotore.iron.constraint.all.*
+
+package object types:
+  type NotEmpty = Not[Empty]
+end types

project/Dependencies.scala

@@ -2,6 +2,7 @@ import sbt.*
 
 object Dependencies {
   val flywayVersion            = "9.16.0"
+  val ironVersion              = "2.4.0"
   val javaJwtVersion           = "4.4.0"
   val javaMailVersion          = "1.6.2"
   val logbackVersion           = "1.4.7"
@@ -22,6 +23,11 @@ object Dependencies {
     "org.flywaydb" % "flyway-core" % flywayVersion
   )
 
+  val iron: List[ModuleID] = List(
+    "io.github.iltotore" %% "iron-zio"      % ironVersion,
+    "io.github.iltotore" %% "iron-zio-json" % ironVersion
+  )
+
   val `java-jwt`: List[ModuleID] = List(
     "com.auth0" % "java-jwt" % javaJwtVersion
   )
@@ -52,11 +58,12 @@ object Dependencies {
 
   val tapir: List[ModuleID] = List(
     "com.softwaremill.sttp.tapir" %% "tapir-sttp-client"       % tapirVersion,
+    "com.softwaremill.sttp.tapir" %% "tapir-iron"              % tapirVersion,
     "com.softwaremill.sttp.tapir" %% "tapir-json-zio"          % tapirVersion,
     "com.softwaremill.sttp.tapir" %% "tapir-zio"               % tapirVersion,
     "com.softwaremill.sttp.tapir" %% "tapir-zio-http-server"   % tapirVersion,
     "com.softwaremill.sttp.tapir" %% "tapir-swagger-ui-bundle" % tapirVersion,
-    "com.softwaremill.sttp.tapir" %% "tapir-sttp-stub-server"  % tapirVersion % "test"
+    "com.softwaremill.sttp.tapir" %% "tapir-sttp-stub-server"  % tapirVersion % Test
   )
 
   val `zio-config`: List[ModuleID] = List(
@@ -90,6 +97,7 @@ object Dependencies {
 
   val dependencies: List[ModuleID] =
     flyway ++
+      iron ++
       `java-jwt` ++
       javaMail ++
       logback ++