Improve Play detection

Glyn Normington · Glyn Normington · commit 7efce76ce256 · 2013-06-28T13:06:49.000+01:00
As well as a start script, a Play application now also needs a
suitable Play JAR in the lib directory.

Add Play to the README.

[#51899933]
diff --git a/README.md b/README.md
@@ -26,6 +26,7 @@ Additional documentation can be found by following the links below.
 * [Design](docs/design.md)
 * Standard Containers
 	* [Java Main Class](docs/container-java-main.md) ([Configuration](docs/container-java-main.md#configuration))
+	* [Play](docs/container-play.md)
 	* [Tomcat](docs/container-tomcat.md) ([Configuration](docs/container-tomcat.md))
 * Standard Frameworks
 	* [`JAVA_OPTS`](docs/framework-java_opts.md) ([Configuration](docs/framework-java_opts.md#configuration))
diff --git a/docs/container-play.md b/docs/container-play.md
@@ -0,0 +1,17 @@
+# JPlay Container
+The Play Container allows Play applications to be run.
+
+<table>
+  <tr>
+    <td><strong>Detection Criteria</strong></td><td><tt>start</tt> script and <tt>lib/play.play_*.jar</tt> exist in the application</td>
+  </tr>
+  <tr>
+    <td><strong>Tags</strong></td><td><tt>Play</tt></td>
+  </tr>
+</table>
+Tags are printed to standard output by the buildpack detect script
+
+## Configuration
+The Play Container cannot be configured.
+
+
diff --git a/lib/java_buildpack/container/play.rb b/lib/java_buildpack/container/play.rb
@@ -43,7 +43,7 @@ def initialize(context)
     # @return [String] returns +Play+ if and only if the application has a +start+ script, otherwise
     #                  returns +nil+
     def detect
-      play_script? ? PLAY_TAG : nil
+      play_app? ? PLAY_TAG : nil
     end
 
     # Makes the +start+ script executable.
@@ -69,8 +69,11 @@ def release
 
     PLAY_TAG = 'Play'.freeze
 
-    def play_script?
-      File.exists?(@start_script_path) && !File.directory?(@start_script_path)
+    PLAY_JAR_PATTERN = 'lib/play.play_*.jar'.freeze
+
+    def play_app?
+      File.exists?(@start_script_path) && !File.directory?(@start_script_path) &&
+          !Dir.glob(File.join(@app_dir, PLAY_JAR_PATTERN)).empty?
     end
 
     def java_opts
diff --git a/spec/fixtures/container_play/lib/play.play_0.0-0.0.0.jar b/spec/fixtures/container_play/lib/play.play_0.0-0.0.0.jar
diff --git a/spec/fixtures/container_play_like/start b/spec/fixtures/container_play_like/start
diff --git a/spec/java_buildpack/container/play_spec.rb b/spec/java_buildpack/container/play_spec.rb
@@ -40,14 +40,22 @@ module JavaBuildpack::Container
       expect(detected).to be_nil
     end
 
-    it 'should detect an application with a start script' do
+    it 'should detect an application with a start script and a suitable Play JAR' do
       detected = Play.new(
           :app_dir => 'spec/fixtures/container_play',
           :configuration => {}).detect
 
       expect(detected).to eq('Play')
     end
 
+    it 'should not detect an application with a start script but no suitable Play JAR' do
+      detected = Play.new(
+          :app_dir => 'spec/fixtures/container_play_like',
+          :configuration => {}).detect
+
+      expect(detected).to be_nil
+    end
+
     it 'should make the start script executable in the compile step' do
       play = Play.new(
           :app_dir => 'spec/fixtures/container_play',
