Add "ActionPlugin" interface

- Plugin for running a custom action

InvenTree/plugins/action/action.py

@@ -0,0 +1,87 @@
+# -*- coding: utf-8 -*-
+
+import plugins.plugin as plugin
+
+
+class ActionPlugin(plugin.InvenTreePlugin):
+    """
+    The ActionPlugin class is used to perform custom actions
+    """
+
+    ACTION_NAME = ""
+
+    @classmethod
+    def action_name(cls):
+        """
+        Return the action name for this plugin.
+        If the ACTION_NAME parameter is empty,
+        look at the PLUGIN_NAME instead.
+        """
+        action = cls.ACTION_NAME
+        
+        if not action:
+            action = cls.PLUGIN_NAME
+        
+        return action
+
+    def __init__(self, user, data=None):
+        """
+        An action plugin takes a user reference, and an optional dataset (dict)
+        """
+        plugin.InvenTreePlugin.__init__(self)
+
+        self.user = user
+        self.data = data
+
+    def perform_action(self):
+        """
+        Override this method to perform the action!
+        """
+        pass
+
+    def get_result(self):
+        """
+        Result of the action?
+        """
+
+        # Re-implement this for cutsom actions
+        return False
+
+    def get_info(self):
+        """
+        Extra info? Can be a string / dict / etc
+        """
+        return None
+
+    def get_response(self):
+        """
+        Return a response. Default implementation is a simple response
+        which can be overridden.
+        """
+        return {
+            "action": self.action_name(),
+            "result": self.get_result(),
+            "info": self.get_info(),
+        }
+
+
+class SimpleActionPlugin(ActionPlugin):
+    """
+    An EXTREMELY simple action plugin which demonstrates
+    the capability of the ActionPlugin class
+    """
+
+    PLUGIN_NAME = "SimpleActionPlugin"
+    ACTION_NAME = "simple"
+
+    def perform_action(self):
+        print("Action plugin in action!")
+
+    def get_info(self):
+        return {
+            "user": self.user.username,
+            "hello": "world",
+        }
+
+    def get_result(self):
+        return True

InvenTree/plugins/plugin.py

@@ -9,7 +9,7 @@ class InvenTreePlugin():
     # Override the plugin name for each concrete plugin instance
     PLUGIN_NAME = ''
 
-    def get_name(self):
+    def plugin_name(self):
         return self.PLUGIN_NAME
 
     def __init__(self):

InvenTree/plugins/plugins.py

@@ -8,6 +8,10 @@ import pkgutil
 import plugins.barcode as barcode
 from plugins.barcode.barcode import BarcodePlugin
 
+# Action plugins
+import plugins.action as action
+from plugins.action.action import ActionPlugin
+
 
 def iter_namespace(pkg):
 
@@ -16,7 +20,7 @@ def iter_namespace(pkg):
 
 def get_modules(pkg):
     # Return all modules in a given package
-    return [importlib.import_module(name) for finder, name, ispkg in iter_namespace(barcode)]
+    return [importlib.import_module(name) for finder, name, ispkg in iter_namespace(pkg)]
 
 
 def get_classes(module):
@@ -41,7 +45,7 @@ def get_plugins(pkg, baseclass):
         # Iterate through each class in the module
         for item in get_classes(mod):
             plugin = item[1]
-            if plugin.__class__ is type(baseclass) and plugin.PLUGIN_NAME:
+            if issubclass(plugin, baseclass) and plugin.PLUGIN_NAME:
                 plugins.append(plugin)
 
     return plugins
@@ -52,6 +56,8 @@ def load_barcode_plugins():
     Return a list of all registered barcode plugins
     """
 
+    print("Loading barcode plugins")
+
     plugins = get_plugins(barcode, BarcodePlugin)
 
     if len(plugins) > 0:
@@ -61,3 +67,21 @@ def load_barcode_plugins():
             print(" - {bp}".format(bp=bp.PLUGIN_NAME))
 
     return plugins
+
+
+def load_action_plugins():
+    """
+    Return a list of all registered action plugins
+    """
+
+    print("Loading action plugins")
+
+    plugins = get_plugins(action, ActionPlugin)
+
+    if len(plugins) > 0:
+        print("Discovered {n} action plugins:".format(n=len(plugins)))
+
+        for ap in plugins:
+            print(" - {ap}".format(ap=ap.PLUGIN_NAME))
+
+    return plugins