rename ravenlog to krowlog

There is a database named RavenDB.
KrowLog starts with a K, which is a) distinctive and b) has an association to KDE.

src/pluginregistry.py

@@ -0,0 +1,78 @@
+from types import ModuleType
+from typing import Dict, Optional
+from inspect import isclass
+from importlib import import_module
+from inspect import signature
+from src.pluginbase import PluginBase
+
+
+class PluginRegistry():
+    plugins: Dict[str, PluginBase] = {}
+
+    modules: [ModuleType] = []
+
+    @staticmethod
+    def _register_plugin(name: str, plugin: PluginBase):
+        PluginRegistry.plugins[name] = plugin
+
+    @staticmethod
+    def load_plugin(plugin_name: str) -> PluginBase:
+        module_name = f"src.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())
+                return plugin_class
+        raise RuntimeError("plugin %s not found" % plugin_name)
+
+    # @staticmethod
+    # def get_modules() -> [ModuleType]:
+    #    return PluginRegistry.modules.copy()
+
+    @staticmethod
+    def get_plugins() -> [PluginBase]:
+        return PluginRegistry.modules.copy()
+
+    @staticmethod
+    def execute_single(function_name: str, *args) -> Optional[any]:
+        return PluginRegistry._execute(function_name, True, *args)
+
+    @staticmethod
+    def execute(function_name: str, *args) -> [any]:
+        return PluginRegistry._execute(function_name, False, *args)
+
+    @staticmethod
+    def _execute(function_name: str, return_first: bool, *args) -> []:
+        result = []
+        for plugin in PluginRegistry.plugins.values():
+            fun = getattr(plugin, function_name, None)
+
+            if callable(fun):
+                sig = signature(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)))
+                # print("calling %s with args %s" % (fun, args))
+                if len(args) == 0:
+                    return_value = fun()
+                elif len(args) == 1:
+                    return_value = fun(args[0])
+                elif len(args) == 2:
+                    return_value = fun(args[0], args[1])
+                elif len(args) == 3:
+                    return_value = fun(args[0], args[1], args[2])
+                elif len(args) == 4:
+                    return_value = fun(args[0], args[1], args[2], args[3])
+                elif len(args) == 5:
+                    return_value = fun(args[0], args[1], args[2], args[3], args[4])
+                else:
+                    raise Exception("too many arguments")
+
+                if return_first:
+                    return return_value
+                result.append(return_value)
+        if return_first:
+            return None
+        return result