frontend build hook logic

Author: yohangz

build.sbt

@@ -1,8 +1,10 @@
-name := """play-java-starter-example"""
+name := """pjava-play-angular-seed"""
 
 version := "1.0-SNAPSHOT"
 
-lazy val root = (project in file(".")).enablePlugins(PlayJava)
+lazy val root = (project in file(".")).enablePlugins(PlayJava).settings(
+  watchSources ++= (baseDirectory.value / "public/ui" ** "*").get
+)
 
 scalaVersion := "2.12.2"
 

project/AngularBuild.scala

@@ -0,0 +1,42 @@
+import java.net.InetSocketAddress
+
+import play.sbt.PlayRunHook
+import sbt._
+
+import scala.sys.process.Process
+
+object AngularBuild {
+  def apply(base: File): PlayRunHook = {
+    object UIBuildHook extends PlayRunHook {
+
+      var process: Option[Process] = None
+
+      var npmInstall: String = "npm install"
+      var npmRun: String = "npm run start"
+
+      // Windows requires npm commands prefixed with cmd /c
+      if (System.getProperty("os.name").toLowerCase().contains("win")){
+        npmInstall = "cmd /c" + npmInstall
+        npmRun = "cmd /c" + npmRun
+      }
+
+      override def beforeStarted(): Unit = {
+        if (!(base / "ui" / "node_modules").exists()) Process(npmInstall, base / "ui").!
+      }
+
+      override def afterStarted(addr: InetSocketAddress): Unit = {
+        process = Option(
+          Process(npmRun, base / "ui").run
+        )
+      }
+
+      override def afterStopped(): Unit = {
+        process.foreach(_.destroy())
+        process = None
+      }
+
+    }
+
+    UIBuildHook
+  }
+}

ui-build.sbt

@@ -0,0 +1,61 @@
+import scala.sys.process.Process
+
+/*
+ * UI Build Scripts
+ */
+val Success = 0 // 0 exit code
+val Error = 1 // 1 exit code
+
+PlayKeys.playRunHooks += baseDirectory.map(AngularBuild.apply).value
+
+val isWindows = System.getProperty("os.name").toLowerCase().contains("win")
+
+def runScript(script: String)(implicit dir: File): Int = {
+  if(isWindows){ Process("cmd /c " + script, dir) } else { Process(script, dir) } }!
+
+def uiWasInstalled(implicit dir: File): Boolean = (dir / "node_modules").exists()
+
+def runNpmInstall(implicit dir: File): Int =
+  if (uiWasInstalled) Success else runScript("npm install")
+
+def ifUiInstalled(task: => Int)(implicit dir: File): Int =
+  if (runNpmInstall == Success) task
+  else Error
+
+// Include UI production build task here.
+def runProdBuild(implicit dir: File): Int = ifUiInstalled(runScript("npm run build-prod"))
+
+// Include UI development build task here.
+def runDevBuild(implicit dir: File): Int = ifUiInstalled(runScript("npm run build-dev"))
+
+// Include UI test build task here.
+def runUiTests(implicit dir: File): Int = ifUiInstalled(runScript("npm run test-no-watch"))
+
+lazy val `ui-dev-build` = TaskKey[Unit]("Run UI build when developing the application.")
+
+`ui-dev-build` := {
+  implicit val userInterfaceRoot = baseDirectory.value / "ui"
+  if (runDevBuild != Success) throw new Exception("Oops! UI Build crashed.")
+}
+
+lazy val `ui-prod-build` = TaskKey[Unit]("Run UI build when packaging the application.")
+
+`ui-prod-build` := {
+  implicit val userInterfaceRoot = baseDirectory.value / "ui"
+  if (runProdBuild != Success) throw new Exception("Oops! UI Build crashed.")
+}
+
+lazy val `ui-test` = TaskKey[Unit]("Run UI tests when testing application.")
+
+`ui-test` := {
+  implicit val userInterfaceRoot = baseDirectory.value / "ui"
+  if (runUiTests != Success) throw new Exception("UI tests failed!")
+}
+
+`ui-test` := (`ui-test` dependsOn `ui-dev-build`).value
+
+dist := (dist dependsOn `ui-prod-build`).value
+
+stage := (stage dependsOn `ui-prod-build`).value
+
+test := ((test in Test) dependsOn `ui-test`).value