Support custom resource.download handlers

README.rst

@@ -67,6 +67,7 @@ Installation
       googleanalytics.track_events = false
       googleanalytics.fields = {}
       googleanalytics.enable_user_id = false
+      ckanext.googleanalytics.download_handler = ckan.views.resource:download
 
    ``resource_prefix`` is an arbitrary identifier so that we can query
    for downloads in Google Analytics.  It can theoretically be any
@@ -93,6 +94,15 @@ Installation
    This way metrics can be tracked for every logged in user. You can read more
    about this feature and its benefits `here <https://support.google.com/analytics/answer/3123662>`_.
 
+   When resource is downloaded, ckanext-googleanalytics posts event to
+   GA and calls default download callback. If you are using CKAN>=2.9
+   and some of your plugins redefines `resource.download`
+   route(ckanext-cloudstorage, for example), you can specify which
+   function must be called instead of `ckan.views.resource:download`
+   via `ckanext.googleanalytics.download_handler` config variable. For ckanext-cloudstorage you can use::
+
+     ckanext.googleanalytics.download_handler = ckanext.cloudstorage.views:download
+
 Domain Linking
 --------------
 

ckanext/googleanalytics/views.py

@@ -5,6 +5,7 @@ import logging
 import six
 
 from flask import Blueprint
+from werkzeug.utils import import_string
 
 import ckan.logic as logic
 import ckan.plugins.toolkit as tk
@@ -13,6 +14,8 @@ import ckan.views.resource as resource
 
 from ckan.common import g
 
+CONFIG_HANDLER_PATH = 'ckanext.googleanalytics.download_handler'
+
 log = logging.getLogger(__name__)
 ga = Blueprint("google_analytics", "google_analytics")
 
@@ -49,6 +52,17 @@ ga.add_url_rule(
 
 
 def download(id, resource_id, filename=None, package_type="dataset"):
+    handler_path = tk.config.get(CONFIG_HANDLER_PATH)
+    if handler_path:
+        handler = import_string(handler_path, silent=True)
+    else:
+        handler = None
+        log.warning((
+            'Missing {} config option.'
+        ).format(CONFIG_HANDLER_PATH))
+    if not handler:
+        log.debug('Use default CKAN callback for resource.download')
+        handler = resource.download
     _post_analytics(
         g.user,
         "CKAN Resource Download Request",
@@ -56,7 +70,9 @@ def download(id, resource_id, filename=None, package_type="dataset"):
         "Download",
         resource_id,
     )
-    return resource.download(package_type, id, resource_id, filename)
+    return handler(
+        package_type=package_type, id=id,
+        resource_id=resource_id, filename=filename)
 
 
 ga.add_url_rule(