Redmine 3.4.4

lib/redmine/hook.rb

@@ -0,0 +1,101 @@
+# Redmine - project management software
+# Copyright (C) 2006-2017  Jean-Philippe Lang
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+
+module Redmine
+  module Hook
+    @@listener_classes = []
+    @@listeners = nil
+    @@hook_listeners = {}
+
+    class << self
+      # Adds a listener class.
+      # Automatically called when a class inherits from Redmine::Hook::Listener.
+      def add_listener(klass)
+        raise "Hooks must include Singleton module." unless klass.included_modules.include?(Singleton)
+        @@listener_classes << klass
+        clear_listeners_instances
+      end
+
+      # Returns all the listener instances.
+      def listeners
+        @@listeners ||= @@listener_classes.collect {|listener| listener.instance}
+      end
+
+      # Returns the listener instances for the given hook.
+      def hook_listeners(hook)
+        @@hook_listeners[hook] ||= listeners.select {|listener| listener.respond_to?(hook)}
+      end
+
+      # Clears all the listeners.
+      def clear_listeners
+        @@listener_classes = []
+        clear_listeners_instances
+      end
+
+      # Clears all the listeners instances.
+      def clear_listeners_instances
+        @@listeners = nil
+        @@hook_listeners = {}
+      end
+
+      # Calls a hook.
+      # Returns the listeners response.
+      def call_hook(hook, context={})
+        [].tap do |response|
+          hls = hook_listeners(hook)
+          if hls.any?
+            hls.each {|listener| response << listener.send(hook, context)}
+          end
+        end
+      end
+    end
+
+    # Helper module included in ApplicationHelper and ActionController so that
+    # hooks can be called in views like this:
+    #
+    #   <%= call_hook(:some_hook) %>
+    #   <%= call_hook(:another_hook, :foo => 'bar') %>
+    #
+    # Or in controllers like:
+    #   call_hook(:some_hook)
+    #   call_hook(:another_hook, :foo => 'bar')
+    #
+    # Hooks added to views will be concatenated into a string. Hooks added to
+    # controllers will return an array of results.
+    #
+    # Several objects are automatically added to the call context:
+    #
+    # * project => current project
+    # * request => Request instance
+    # * controller => current Controller instance
+    # * hook_caller => object that called the hook
+    #
+    module Helper
+      def call_hook(hook, context={})
+        if is_a?(ActionController::Base)
+          default_context = {:controller => self, :project => @project, :request => request, :hook_caller => self}
+          Redmine::Hook.call_hook(hook, default_context.merge(context))
+        else
+          default_context = { :project => @project, :hook_caller => self }
+          default_context[:controller] = controller if respond_to?(:controller)
+          default_context[:request] = request if respond_to?(:request)
+          Redmine::Hook.call_hook(hook, default_context.merge(context)).join(' ').html_safe
+        end
+      end
+    end
+  end
+end