Apply fix from #446 to replace pkg_resources with importlib (#485)

Author: dnerini

pysteps/io/interface.py

@@ -12,7 +12,7 @@
 
     get_method
 """
-import importlib
+from importlib.metadata import entry_points
 
 from pysteps.decorators import postprocess_import
 from pysteps.io import importers, exporters, interface
@@ -46,17 +46,11 @@ def discover_importers():
     The importers found are added to the `pysteps.io.interface_importer_methods`
     dictionary containing the available importers.
     """
-    # The pkg resources needs to be reload to detect new packages installed during
-    # the execution of the python application. For example, when the plugins are
-    # installed during the tests
-    import pkg_resources
-
-    importlib.reload(pkg_resources)
     # Backward compatibility with previous entry point 'pysteps.plugins.importers' next to 'pysteps.plugins.importer'
     for entry_point in list(
-        pkg_resources.iter_entry_points(group="pysteps.plugins.importer", name=None)
+        entry_points(group="pysteps.plugins.importer")
     ) + list(
-        pkg_resources.iter_entry_points(group="pysteps.plugins.importers", name=None)
+        entry_points(group="pysteps.plugins.importers")
     ):
         _importer = entry_point.load()
 
@@ -71,14 +65,14 @@ def discover_importers():
             RuntimeWarning(
                 f"The importer identifier '{importer_short_name}' is already available in"
                 "'pysteps.io.interface._importer_methods'.\n"
-                f"Skipping {entry_point.module_name}:{entry_point.attrs}"
+                f"Skipping {entry_point.module}:{entry_point.attr}"
             )
 
         if hasattr(importers, importer_function_name):
             RuntimeWarning(
                 f"The importer function '{importer_function_name}' is already an attribute"
                 "of 'pysteps.io.importers`.\n"
-                f"Skipping {entry_point.module_name}:{entry_point.attrs}"
+                f"Skipping {entry_point.module}:{entry_point.attr}"
             )
         else:
             setattr(importers, importer_function_name, _importer)

pysteps/postprocessing/interface.py

@@ -17,6 +17,7 @@
     get_method
 """
 import importlib
+from importlib.metadata import entry_points
 
 from pysteps.postprocessing import diagnostics, ensemblestats
 from pprint import pprint
@@ -82,28 +83,19 @@ def discover_postprocessors():
     dictionary in 'pysteps.postprocessing.interface' containing the available postprocessors.
     """
 
-    # The pkg resources needs to be reloaded to detect new packages installed during
-    # the execution of the python application. For example, when the plugins are
-    # installed during the tests
-    import pkg_resources
-
-    importlib.reload(pkg_resources)
-
     # Discover the postprocessors available in the plugins
     for plugintype in ["diagnostic", "ensemblestat"]:
-        for entry_point in pkg_resources.iter_entry_points(
-            group=f"pysteps.plugins.{plugintype}", name=None
-        ):
+        for entry_point in entry_points(group=f"pysteps.plugins.{plugintype}"):
             _postprocessors = entry_point.load()
 
             postprocessors_function_name = _postprocessors.__name__
 
-            if plugintype in entry_point.module_name:
+            if plugintype in entry_point.module:
                 add_postprocessor(
                     postprocessors_function_name,
                     _postprocessors,
                     f"{plugintype}s",
-                    entry_point.attrs,
+                    entry_point.attr,
                 )