Look for a REVISION file before running git log

Author: jacobvosmaer

CHANGELOG

@@ -5,6 +5,7 @@ v5.1
   - Add support for skip branches from build
   - Add coverage parsing feature
   - Update rails to 4.0.10
+  - Look for a REVISION file before running `git log`
 
 v5.0.1
   - Update rails to 4.0.5

config/initializers/2_app.rb

@@ -1,6 +1,15 @@
 module GitlabCi
   VERSION = File.read(Rails.root.join("VERSION")).strip
-  REVISION = `git log --pretty=format:'%h' -n 1`
+
+  # Try to read the current Git revision from a REVISION file. This is used by
+  # the omnibus packages.
+  revision_file = Rails.root.join('REVISION')
+  if File.exist?(revision_file)
+    REVISION = File.read(revision_file).strip
+  else
+    REVISION = `git log --pretty=format:'%h' -n 1`
+  end
+
   REGISTRATION_TOKEN = SecureRandom.hex(10)
 
   def self.config