Automatically register all extensions in the extension directory (without explicit init import)

openflexure_microscope/api/default_extensions/__init__.py

@@ -0,0 +1,3 @@
+from .autofocus import autofocus_extension_v2
+from .scan import scan_extension_v2
+from .zip_builder import zip_extension_v2

openflexure_microscope/api/utilities.py

@@ -109,7 +109,7 @@ def create_file(config_path):
 
 
 def init_default_extensions(extension_path):
-    global _DEFAULT_extension_INIT
+    global _DEFAULT_EXTENSION_INIT
     os.makedirs(os.path.dirname(extension_path), exist_ok=True)
 
     if not os.path.exists(extension_path):  # If user extensions file doesn't exist
@@ -118,13 +118,7 @@ def init_default_extensions(extension_path):
 
         logging.info("Populating {}...".format(extension_path))
         with open(extension_path, "w") as outfile:
-            outfile.write(_DEFAULT_extension_INIT)
+            outfile.write(_DEFAULT_EXTENSION_INIT)
 
 
-_DEFAULT_extension_INIT = """
-from openflexure_microscope.api.default_extensions.autofocus import autofocus_extension_v2
-from openflexure_microscope.api.default_extensions.scan import scan_extension_v2
-from openflexure_microscope.api.default_extensions.zip_builder import zip_extension_v2
-
-__extensions__ = [autofocus_extension_v2, scan_extension_v2, zip_extension_v2]
-"""
+_DEFAULT_EXTENSION_INIT = "from openflexure_microscope.api.default_extensions import *"

openflexure_microscope/common/flask_labthings/extensions.py

@@ -4,6 +4,8 @@ import copy
 
 from importlib import util
 import sys
+import os
+import glob
 
 from openflexure_microscope.common.labthings_core.utilities import get_docstring
 from openflexure_microscope.utilities import camel_to_snake, snake_to_spine
@@ -123,7 +125,16 @@ class BaseExtension:
             )
 
 
-def find_extensions(extension_path, module_name="extensions"):
+def find_instances_in_module(module, class_to_find):
+    objs = []
+    for attribute in dir(module):
+        if not attribute.startswith("__"):
+            if isinstance(getattr(module, attribute), class_to_find):
+                objs.append(getattr(module, attribute))
+    return objs
+
+
+def find_extensions_in_file(extension_path, module_name="extensions"):
     logging.debug(f"Loading extensions from {extension_path}")
 
     spec = util.spec_from_file_location(module_name, extension_path)
@@ -133,6 +144,18 @@ def find_extensions(extension_path, module_name="extensions"):
     spec.loader.exec_module(mod)
 
     if hasattr(mod, "__extensions__"):
-        return mod.__extensions__
+        return [getattr(mod, ext_name) for ext_name in mod.__extensions__]
     else:
-        return None
+        return find_instances_in_module(mod, BaseExtension)
+
+
+def find_extensions(extension_dir, module_name="extensions"):
+    logging.debug(f"Loading extensions from {extension_dir}")
+
+    extensions = []
+    extension_paths = glob.glob(os.path.join(extension_dir, "*.py"))
+
+    for extension_path in extension_paths:
+        extensions.extend(find_extensions_in_file(extension_path, module_name=module_name))
+
+    return extensions

openflexure_microscope/config.py

@@ -182,7 +182,7 @@ DEFAULT_CONFIG_FILE_PATH = os.path.join(HERE, "microscope_settings.default.json"
 
 USER_CONFIG_DIR = os.path.join(os.path.expanduser("~"), ".openflexure")
 USER_CONFIG_FILE_PATH = os.path.join(USER_CONFIG_DIR, "microscope_settings.json")
-USER_EXTENSIONS_PATH = os.path.join(USER_CONFIG_DIR, "microscope_extensions", "__init__.py")
+USER_EXTENSIONS_PATH = os.path.join(USER_CONFIG_DIR, "microscope_extensions")
 
 # Load the default config
 with open(DEFAULT_CONFIG_FILE_PATH, "r") as default_rc: