Add mongodb_version fact

Author: Joseph Yaworski

lib/facter/mongodb_version.rb

@@ -0,0 +1,8 @@
+Facter.add(:mongodb_version) do
+  setcode do
+    if Facter::Core::Execution.which('mongo')
+      mongodb_version = Facter::Core::Execution.execute('mongo --version 2>&1')
+      %r{^MongoDB shell version: ([\w\.]+)}.match(mongodb_version)[1]
+    end
+  end
+end

spec/unit/mongodb_version_spec.rb

@@ -0,0 +1,19 @@
+require "spec_helper"
+
+describe Facter::Util::Fact do
+  before {
+    Facter.clear
+  }
+
+  describe "mongodb_version" do
+    context 'with value' do
+      before :each do
+        Facter::Core::Execution.stubs(:which).with('mongo').returns(true)
+        Facter::Core::Execution.stubs(:execute).with('mongo --version 2>&1').returns('MongoDB shell version: 3.2.1')
+      end
+      it {
+        expect(Facter.fact(:mongodb_version).value).to eq('3.2.1')
+      }
+    end
+  end
+end