SystemD services now source /etc/default/{{app_name}} #737

This change modifies the SystemD template to include the packaged
/etc/default environment settings file. Since a sourced SystemD
environment file is not the same thing as a bourne shell source script,
a different template is used.

Those deploying their package to multiple platforms can also specify
different /etc/default templates by suffixing `-systemd` to their name,
ie: src/templates/etc-default-systemd

Author: timcharper

.gitignore

@@ -9,3 +9,4 @@ project/project
 log/
 target/
 .cache
+.ensime*

src/main/resources/com/typesafe/sbt/packager/archetypes/etc-default-systemd-template

@@ -0,0 +1,27 @@
+# #####################################
+# ##### Environment Configuration #####
+# #####################################
+
+# This file is parsed by SystemD. You can modify it to specify environment
+# variables for your application.  For a description of the format, see `man
+# systemd.exec`, section `EnvironmentFile`.
+
+# Available replacements
+# ------------------------------------------------
+# ${{author}}			debian author
+# ${{descr}}			debian package description
+# ${{exec}}				startup script name
+# ${{chdir}}			app directory
+# ${{retries}}			retries for startup
+# ${{retryTimeout}}		retry timeout
+# ${{app_name}}			normalized app name
+# ${{daemon_user}}		daemon user
+# -------------------------------------------------
+
+# Setting JAVA_OPTS
+# -----------------
+# JAVA_OPTS="-Dpidfile.path=/var/run/${{app_name}}/play.pid"
+
+# Setting PIDFILE
+# ---------------
+# PIDFILE="/var/run/${{app_name}}/play.pid"

src/main/resources/com/typesafe/sbt/packager/archetypes/java_server/systemloader/systemd/start-template

@@ -5,6 +5,7 @@ Requires=${{start_facilities}}
 [Service]
 Type=simple
 WorkingDirectory=${{chdir}}
+EnvironmentFile=${{env_config}}
 ExecStart=${{chdir}}/bin/${{exec}}
 ExecReload=/bin/kill -HUP $MAINPID
 Restart=always

src/main/scala/com/typesafe/sbt/packager/archetypes/JavaServerApplication.scala

@@ -39,8 +39,6 @@ object JavaServerAppPackaging extends AutoPlugin {
   /** These settings will be provided by this archetype*/
   def javaServerSettings: Seq[Setting[_]] = linuxSettings ++ debianSettings ++ rpmSettings
 
-  protected def etcDefaultTemplateSource: java.net.URL = getClass.getResource(ETC_DEFAULT + "-template")
-
   /**
    * general settings which apply to all linux server archetypes
    *
@@ -59,27 +57,26 @@ object JavaServerAppPackaging extends AutoPlugin {
     },
     // === etc config mapping ===
     bashScriptEnvConfigLocation := Some("/etc/default/" + (packageName in Linux).value),
-    linuxEtcDefaultTemplate <<= sourceDirectory map { dir =>
-      val overrideScript = dir / "templates" / ETC_DEFAULT
-      if (overrideScript.exists) overrideScript.toURI.toURL
-      else etcDefaultTemplateSource
-    },
-    linuxStartScriptName := None,
-    makeEtcDefault <<= (packageName in Linux, target in Universal, linuxEtcDefaultTemplate, linuxScriptReplacements)
-      map makeEtcDefaultScript,
-    linuxPackageMappings <++= (makeEtcDefault, bashScriptEnvConfigLocation) map { (conf, envLocation) =>
-      val mapping = for (
-        path <- envLocation;
-        c <- conf
-      ) yield LinuxPackageMapping(Seq(c -> path), LinuxFileMetaData(Users.Root, Users.Root, "644")).withConfig()
+    // (serverLoading in Rpm) apply getStartScriptLocation
 
-      mapping.toSeq
-    }
+    linuxStartScriptName := None
+  )
 
+  /* etcDefaultConfig is dependent on serverLoading (systemd, systemv, etc.),
+   * and is therefore distro specific. As such, these settings cannot be defined
+   * generally. */
+  private val etcDefaultConfig: Seq[Setting[_]] = Seq(
+    linuxEtcDefaultTemplate <<= (sourceDirectory, serverLoading)
+      map getEtcTemplateSource,
+    makeEtcDefault <<= (packageName in Linux, target in Universal, linuxEtcDefaultTemplate, linuxScriptReplacements)
+      map makeEtcDefaultScript,
+    linuxPackageMappings <++= (makeEtcDefault, bashScriptEnvConfigLocation) map
+      etcDefaultMapping
   )
 
   def debianSettings: Seq[Setting[_]] = {
     import DebianPlugin.Names.{ Preinst, Postinst, Prerm, Postrm }
+    inConfig(Debian)(etcDefaultConfig) ++
     inConfig(Debian)(Seq(
       serverLoading := Upstart,
       startRunlevels <<= (serverLoading) apply defaultStartRunlevels,
@@ -131,6 +128,7 @@ object JavaServerAppPackaging extends AutoPlugin {
 
   def rpmSettings: Seq[Setting[_]] = {
     import RpmPlugin.Names.{ Pre, Post, Preun, Postun }
+    inConfig(Rpm)(etcDefaultConfig) ++
     inConfig(Rpm)(Seq(
       serverLoading := SystemV,
       startRunlevels <<= (serverLoading) apply defaultStartRunlevels,
@@ -242,6 +240,33 @@ object JavaServerAppPackaging extends AutoPlugin {
     }
   }
 
+  private[this] def getEtcTemplateSource(sourceDirectory: File, loader: ServerLoader): java.net.URL = {
+    val suffix = loader match {
+      case Upstart => "-upstart"
+      case SystemV => "-systemv"
+      case Systemd => "-systemd"
+    }
+
+    val overrides = List[File](sourceDirectory / "templates" / (ETC_DEFAULT + suffix), sourceDirectory / "templates" / ETC_DEFAULT)
+    overrides.find(_.exists).map(_.toURI.toURL).getOrElse {
+      loader match {
+        case Upstart => getClass.getResource(ETC_DEFAULT + "-template")
+        case SystemV => getClass.getResource(ETC_DEFAULT + "-template")
+        case Systemd => getClass.getResource(ETC_DEFAULT + "-systemd-template")
+      }
+    }
+  }
+
+  // Used to tell our packager to install our /etc/default/{{appName}} config file.
+  protected def etcDefaultMapping(conf: Option[File], envLocation: Option[String]): Seq[LinuxPackageMapping] = {
+    val mapping = for (
+      path <- envLocation;
+      c <- conf
+    ) yield LinuxPackageMapping(Seq(c -> path), LinuxFileMetaData(Users.Root, Users.Root, "644")).withConfig()
+
+    mapping.toSeq
+  }
+
   protected def startScriptMapping(name: String, script: Option[File], loader: ServerLoader, scriptDir: String, scriptName: Option[String]): Seq[LinuxPackageMapping] = {
     val (path, permissions, isConf) = loader match {
       case Upstart => ("/etc/init/" + scriptName.getOrElse(name + ".conf"), "0644", "true")