Automatically load API endpoint plugins

openflexure_microscope/api/v1/blueprints/plugins.py

@@ -0,0 +1,50 @@
+from openflexure_microscope.api.utilities import parse_payload, get_from_payload, gen, get_bool
+from openflexure_microscope.api.v1.views import MicroscopeView
+
+from openflexure_microscope.plugins import load_plugin, search_plugin_dirs
+
+from flask import Response, Blueprint, jsonify
+
+import logging, warnings
+
+
+def add_endpoints(plugin_module, endpoint_dict):
+    """
+    Fetch valid endpoints from a plugin_module
+
+    Args:
+        plugin_module: A loaded module to be attached. Module can be loaded using :py:meth:`openflexure_microscope.plugins.load_plugin`
+    """
+    if hasattr(plugin_module, 'ENDPOINTS') and isinstance(plugin_module.ENDPOINTS, dict):  # If plugin contains valid endpoints
+
+        for endpoint_name, endpoint_class in plugin_module.ENDPOINTS.items():  # For each defined endpoint
+
+            if endpoint_name in endpoint_dict:  # Check if endpoint name clashes
+                warnings.warn("An endpoint /{} has already been loaded. Skipping {}.".format(endpoint_name, endpoint_class))
+            else:
+                endpoint_dict[endpoint_name] = endpoint_class  # Add endpoint to main endpoint dictionary
+    else:
+        warnings.warn("No valid ENDPOINTS dictionary found in {}".format(plugin_module))
+
+
+def construct_blueprint(microscope_obj, plugin_paths=[], include_default=True):
+
+    blueprint = Blueprint('plugin_blueprint', __name__)
+
+    logging.debug("Attaching plugins...")
+    plugins_list = search_plugin_dirs(plugin_paths, include_default=include_default)
+
+    endpoint_dict = {}  # Store all endpoints
+
+    for plugin_file in plugins_list:
+        plugin_module = load_plugin(plugin_file)
+        add_endpoints(plugin_module, endpoint_dict)
+
+    for endpoint_name, endpoint_class in endpoint_dict.items():  # For each valid endpoint
+
+        blueprint.add_url_rule(
+            '/{}'.format(endpoint_name),
+            view_func=endpoint_class.as_view('plugin_{}'.format(endpoint_name), microscope=microscope_obj)
+        )
+
+    return(blueprint)