Merge pull request #2354 from jezdez/redash-extensions

Add a Redash extension system based on Python entrypoints.

redash/__init__.py

@@ -91,7 +91,7 @@ def to_url(self, value):
 
 
 def create_app(load_admin=True):
-    from redash import handlers
+    from redash import extensions, handlers
     from redash.handlers.webpack import configure_webpack
     from redash.admin import init_admin
     from redash.models import db
@@ -137,5 +137,5 @@ def create_app(load_admin=True):
     limiter.init_app(app)
     handlers.init_app(app)
     configure_webpack(app)
-
+    extensions.init_extensions(app)
     return app

redash/extensions.py

@@ -0,0 +1,14 @@
+from pkg_resources import iter_entry_points
+
+
+def init_extensions(app):
+    """
+    Load the Redash extensions for the given Redash Flask app.
+    """
+    if not hasattr(app, 'redash_extensions'):
+        app.redash_extensions = {}
+
+    for entry_point in iter_entry_points('redash.extensions'):
+        app.logger.info('Loading Redash extension %s.', entry_point.name)
+        extension = entry_point.load()
+        app.redash_extensions[entry_point.name] = extension(app)