From 1ea10e293391b006e634105bd58d2728b756598b Mon Sep 17 00:00:00 2001
From: Andreas Huber <andreas.huber@lucares.de>
Date: Sat, 13 Nov 2021 18:32:28 +0100
Subject: [PATCH] show how to call methods on plugins

---
 raven/pluginregistry.py              | 22 +++++++++++++++++-----
 raven/plugins/filterplugin.py        |  3 +++
 raven/plugins/logfileviewerplugin.py |  3 +++
 raven/ravenlog.py                    |  5 ++---
 4 files changed, 25 insertions(+), 8 deletions(-)

diff --git a/raven/pluginregistry.py b/raven/pluginregistry.py
index 28886f9..3acdb31 100644
--- a/raven/pluginregistry.py
+++ b/raven/pluginregistry.py
@@ -5,6 +5,7 @@ from pkgutil import iter_modules
 from pathlib import Path
 from os.path import dirname
 from importlib import import_module
+from inspect import signature
 from raven.pluginbase import PluginBase
 
 
@@ -29,27 +30,38 @@ class PluginRegistry():
     @staticmethod
     def load_module(module_name: str) -> ModuleType:
         module_name = f"plugins.{module_name}"
-        # import the module and iterate through its attributes
         module = import_module(module_name)
         PluginRegistry.modules.append(module)
         return module
 
     @staticmethod
-    def load_plugin(plugin_name: str):
+    def load_plugin(plugin_name: str) -> PluginBase:
         module_name = f"plugins.{plugin_name.lower()}"
         module = import_module(module_name)
         if plugin_name in dir(module):
             plugin_class = getattr(module, plugin_name)
 
             if isclass(plugin_class) and issubclass(plugin_class, PluginBase):
-                PluginRegistry.register_plugin(plugin_name, plugin_class)
-                print("%s -> %s :: %s in %s" % (plugin_name, plugin_class, module_name, module))
+                PluginRegistry.register_plugin(plugin_name, plugin_class())
                 return plugin_class
+        raise RuntimeError("plugin %s not found" % plugin_name)
 
     @staticmethod
     def get_modules() -> [ModuleType]:
         return PluginRegistry.modules.copy()
 
     @staticmethod
-    def get_plugins() -> [ModuleType]:
+    def get_plugins() -> [PluginBase]:
         return PluginRegistry.modules.copy()
+
+    @staticmethod
+    def execute(function_name: str, *args):
+        for plugin in PluginRegistry.plugins.values():
+            fun = getattr(plugin, function_name, None)
+
+            sig = signature(fun)
+            if callable(fun):
+                if len(sig.parameters) != len(args):
+                    raise RuntimeError("method %s.%s has wrong number of arguments. expected %s but was %s " % (
+                    plugin, function_name, len(args), len(sig.parameters)))
+                fun(args)
diff --git a/raven/plugins/filterplugin.py b/raven/plugins/filterplugin.py
index caade22..7564428 100644
--- a/raven/plugins/filterplugin.py
+++ b/raven/plugins/filterplugin.py
@@ -6,6 +6,9 @@ class FilterPlugin(PluginBase):
         super(FilterPlugin, self).__init__()
         print("init FilterPlugin")
 
+    def say_hello(self, arg: str):
+        print("FilterPlugin says hello %s" % arg)
+
 
 def init():
     print("initializing filter plugin")
diff --git a/raven/plugins/logfileviewerplugin.py b/raven/plugins/logfileviewerplugin.py
index fecbc12..fa9406c 100644
--- a/raven/plugins/logfileviewerplugin.py
+++ b/raven/plugins/logfileviewerplugin.py
@@ -5,3 +5,6 @@ class LogFileViewerPlugin(PluginBase):
     def __init__(self):
         super(LogFileViewerPlugin, self).__init__()
         print("init LogFileViewerPlugin")
+
+    def say_hello(self, *args):
+        print("LogFileViewerPlugin says hello")
diff --git a/raven/ravenlog.py b/raven/ravenlog.py
index 5ce3fab..229c93e 100644
--- a/raven/ravenlog.py
+++ b/raven/ravenlog.py
@@ -63,10 +63,9 @@ def set_window_icon(app: QApplication):
 
 if __name__ == "__main__":
     filterplugin = PluginRegistry.load_plugin("FilterPlugin")
-    filterplugin()
-
     logfileviewerplugin = PluginRegistry.load_plugin("LogFileViewerPlugin")
-    logfileviewerplugin()
+
+    PluginRegistry.execute("say_hello", "World")
 
     app = QApplication(sys.argv)
     set_window_icon(app)