umask can also be set via bashScriptExtraDefines (#1274)

src/sphinx/archetypes/cheatsheet.rst

@@ -98,7 +98,7 @@ For a bash script this could look like this.
         """addJava "-Xmx2048m""""
      )
 
-For information take a look at the :doc:` customize section for java apps </archetypes/java_app/customize>`
+For more information take a look at the :ref:`according documentation<add-code-to-the-start-scripts>`.
 
 File - application.ini or etc-default
 -------------------------------------

src/sphinx/archetypes/java_app/customize.rst

@@ -123,6 +123,7 @@ The default configuration looks like this
     bashScriptConfigLocation := Some("${app_home}/../conf/application.ini")
     batScriptConfigLocation := Some("%APP_HOME%\\conf\\application.ini")
 
+.. _add-code-to-the-start-scripts:
 
 Add code to the start scripts
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

src/sphinx/recipes/index.rst

@@ -17,5 +17,6 @@ This section provides recipes for common configurations. If you can't find what
    scalajs
    package_configuration
    embedded-jvm
+   umask
 
 .. _sbt-native-packager examples: https://github.com/muuki88/sbt-native-packager-examples

src/sphinx/recipes/umask.rst

@@ -3,18 +3,36 @@
 Setting the umask for your process
 ==================================
 
-When using the :ref:`java-server-plugin`, the umask, associated with the user running the process, 
-will determine what permissions files generated by the process, such as log file, will have.  Usually the system default umask
-for daemons is fine and can be left unchanged, however sometime the need arises to oerride it.
+In Linux, the umask, associated with the user running the process, will determine what permissions files generated by the process,
+such as log files, will have.
+
+Within the start script
+-------------------------------------
+
+You can set the umask within the generated start script:
+
+.. code-block:: scala
+
+   bashScriptExtraDefines += "umask 077"
+
+This line will be added just before the application will be executed by the start script and therefore the application process
+will also inhert this umask. For more information take a look at the :ref:`according documentation<bash-script-defines>`.
+
+.. hint:: When using :ref:`Docker<docker-plugin>` this is the only reliable way `right now <https://github.com/moby/moby/issues/19189>`_ to set the umask for the process. Docker `will ignore <https://stackoverflow.com/a/46900270/810109>`_ any umask set in e.g. `/etc/login.defs` (or other config files) within a docker image.
 
 System V/systemd
 ----------------
 
-To set a custom umask for your application that is running either via a System V init script or systemd, the umask can be 
-specified via a custom ``/etc/default/appname`` file.  The contents of this file can be specified by creating a template at 
-``src/templates/etc-default`` and adding a line such as the following:
+When using the :ref:`java-server-plugin` usually the system default umask for daemons is fine and can be left unchanged,
+however sometime the need arises to override it.
+
+As an alternative to the start script approach described in the section above, to set a custom umask for
+your application that is running either via a System V init script or systemd, the umask can be specified via
+a custom ``/etc/default/appname`` file.
+
+The contents of this file can be specified by creating a template at ``src/templates/etc-default`` and adding a line such as the following:
 
 
 .. code-block:: bash
 
-    umask 022
+    umask 077