Display the git tag, branch/commit or version when possible

Signed-off-by: Yann Lopez <[email protected]>

app/views/layouts/application.html.slim

@@ -45,3 +45,6 @@ html
         'Created with
         i.fa.fa-heart
         'by the SUSE team
+      - if current_user.admin? && Version.value
+          p
+            'Version: #{Version.value}

config/initializers/version.rb

@@ -0,0 +1,28 @@
+require 'mkmf'
+
+# Version module
+# Makes the app version available to the application itself
+# Needs the git executable for all git operations
+module Version
+  git = find_executable('git')
+  BRANCH = git ? `git symbolic-ref HEAD 2>/dev/null | cut -d"/" -f 3  2>/dev/null`.chomp : nil
+  COMMIT = git ? `git log --pretty=format:'%h' -n 1 2>/dev/null`.chomp : nil
+  TAG = git ? `git tag --points-at $(git rev-parse HEAD) 2>/dev/null`.chomp : nil
+
+  # Version.value returns the app version
+  # Priority: git tag > git branch/commit > VERSION file
+  def self.value
+    if TAG.present?
+      "#{TAG}"
+    elsif COMMIT.present?
+      if BRANCH.present?
+        "#{BRANCH}@#{COMMIT}"
+      else
+        "#{COMMIT}"
+      end
+    else
+      version = Rails.root.join("VERSION")
+      File.read(version).chomp if File.exists?(version)
+    end
+  end
+end