Add HealthCheck and HealthCheckable

HealthCheck is a basic library for creating health checks.

HealthCheck works with any class so long as it includes HealthCheckable
and defines the `check` method.

2 files changed, 65 insertions, 0 deletions

diff --git a/lib/health_checks/health_checkable.rb b/lib/health_checks/health_checkable.rb
new file mode 100644
index 000000000..5d674ca32
--- /dev/null
+++ b/lib/health_checks/health_checkable.rb
@@ -0,0 +1,28 @@
+module HealthChecks
+    module HealthCheckable
+
+        attr_accessor :failure_message, :success_message
+
+        def initialize(args = {})
+            self.failure_message = args.fetch(:failure_message) { _('Failed') }
+            self.success_message = args.fetch(:success_message) { _('Success') }
+        end
+
+        def name
+            self.class.to_s
+        end
+
+        def check
+            raise NotImplementedError
+        end
+
+        def ok?
+            check ? true : false
+        end
+
+        def message
+            ok? ? success_message : failure_message
+        end
+
+    end
+end
diff --git a/lib/health_checks/health_checks.rb b/lib/health_checks/health_checks.rb
new file mode 100644
index 000000000..6f0c9de8e
--- /dev/null
+++ b/lib/health_checks/health_checks.rb
@@ -0,0 +1,37 @@
+require 'health_checkable'
+
+Dir[File.dirname(__FILE__) + '/checks/*.rb'].each do |file|
+    require file
+end
+
+module HealthChecks
+    extend self
+
+    def all
+        @checks ||= []
+    end
+
+    def add(check)
+        if assert_valid_check(check)
+            all << check
+            check
+        else
+            false
+        end
+    end
+
+    def each(&block)
+      all.each(&block)
+    end
+
+    def ok?
+       all.all? { |check| check.ok? }
+    end
+
+    private
+
+    def assert_valid_check(check)
+        check.respond_to?(:check)
+    end
+
+end