Update debug panel so signals are always sent when available

Addresses #4 and #7

CHANGELOG.rst

@@ -27,6 +27,9 @@ any necessary information about installation or upgrade notes.
 * Removed ``overwrite`` option from :meth:`eulexistdb.ExistDB.load`
   (no longer applicable under the REST API, and misleading)
   `#9 <https://github.com/emory-libraries/eulexistdb/issues/9>`_
+* Improved django-debug-toolbar integration. Addresses
+  `#7 <https://github.com/emory-libraries/eulexistdb/issues/7>`_
+  and `#8 <https://github.com/emory-libraries/eulexistdb/issues/8>`_.
 
 0.20
 ----

eulexistdb/db.py

@@ -99,11 +99,17 @@
 import logging
 import requests
 import socket
+import time
 from urllib import unquote_plus, splittype
 import urlparse
 import warnings
 import xmlrpclib
 
+try:
+    from django.dispatch import Signal
+except ImportError:
+    Signal = None
+
 from . import patch
 from eulxml import xmlmap
 from eulexistdb.exceptions import ExistDBException, ExistDBTimeout
@@ -114,6 +120,7 @@
 
 EXISTDB_NAMESPACE = 'http://exist.sourceforge.net/NS/exist'
 
+
 def _wrap_xmlrpc_fault(f):
     @wraps(f)
     def wrapper(*args, **kwargs):
@@ -129,6 +136,12 @@ def wrapper(*args, **kwargs):
         # error: [Errno 104] Connection reset by peer
     return wrapper
 
+xquery_called = None
+if Signal is not None:
+    xquery_called = Signal(providing_args=[
+        "time_taken", "name", "return_value", "args", "kwargs"])
+
+
 
 class ExistDB(object):
     """Connect to an eXist database, and manipulate and query it.
@@ -484,10 +497,18 @@ def query(self, xquery=None, start=1, how_many=10, cache=False, session=None,
         else:
             debug_query = ''
         logger.debug('query %s%s' % (opts, debug_query))
-
+        start = time.time()
         response = self.session.get(self.restapi_path(''), params=params,
                                     stream=False, **self.session_opts)
 
+        if xquery_called is not None:
+            args = {'xquery': xquery, 'start': start, 'how_many': how_many,
+                    'cache': cache, 'session': session, 'release': release,
+                    'result_type': result_type}
+            xquery_called.send(
+                sender=self.__class__, time_taken=time.time() - start,
+                name='query', return_value=response, args=[], kwargs=args)
+
         if response.status_code == requests.codes.ok:
             # successful release doesn't return any content
             if release is not None:

eulexistdb/debug_panel.py

@@ -22,23 +22,6 @@
 # implementation based on django-debug-toolbar cache panel
 
 
-xquery_called = Signal(providing_args=[
-    "time_taken", "name", "return_value", "args", "kwargs"])
-
-
-class ExistDBTracker(db.ExistDB):
-    # subclass ExistDB in order to track query calls
-
-    def query(self, *args, **kwargs):
-        start = time.time()
-        value = super(ExistDBTracker, self).query(*args, **kwargs)
-        total_time = time.time() - start
-        xquery_called.send(sender=self.__class__, time_taken=total_time,
-                           name='query', return_value=value,
-                           args=args, kwargs=kwargs)
-        return value
-
-
 class ExistDBPanel(Panel):
 
     name = 'ExistDB'
@@ -51,7 +34,7 @@ def __init__(self, *args, **kwargs):
         self.total_time = 0
         self.queries = []
 
-        xquery_called.connect(self._store_xquery_info)
+        db.xquery_called.connect(self._store_xquery_info)
 
     def _store_xquery_info(self, sender, name=None, time_taken=0,
                           return_value=None, args=None, kwargs=None,
@@ -65,6 +48,11 @@ def _store_xquery_info(self, sender, name=None, time_taken=0,
         if hasattr(return_value, 'serialize'):
             return_value = return_value.serialize()
 
+        # remove empty values from kwargs, to simplify display
+        for k, val in list(kwargs.iteritems()):
+            if val is None:
+                del args[k]
+
         time_taken *= 1000
         self.total_time += time_taken
         self.queries.append({
@@ -85,19 +73,10 @@ def title(self):
         return self.name
 
     def nav_subtitle(self):
-        return "%(xqueries)d queries in %(time).2fms" % \
-               {'xqueries': len(self.queries), 'time': self.total_time}
-
-    def enable_instrumentation(self):
-        # patch tracking existdb subclass in for the real one
-        db.RealExistDB = db.ExistDB
-        eulexistdb.db.ExistDB = ExistDBTracker
-        # also patch into the manager module (already imported)
-        eulexistdb.manager.ExistDB = db.ExistDB
-
-    def disable_instrumentation(self):
-        db.ExistDB = db.RealExistDB
-        eulexistdb.manager.ExistDB = db.ExistDB
+        return "%(xqueries)d quer%(plural)s in %(time).2fms" % \
+               {'xqueries': len(self.queries),
+                'plural': 'y' if (len(self.queries) == 1) else 'ies',
+                'time': self.total_time}
 
     def generate_stats(self, request, response):
         # statistics for display in the template

eulexistdb/templates/eulexistdb/debug_panel.html

@@ -1,4 +1,4 @@
-{% load i18n %}{% load cycle from debug_toolbar_compat %}
+{% load i18n %}
 <h4>{% trans "Summary" %}</h4>
 <table>
 	<thead>
@@ -35,7 +35,9 @@ <h4>{% trans "Queries" %}</h4>
 			<td>{{ query.time|floatformat:"4" }}</td>
 			<td><pre>{% firstof query.args.0 query.kwargs.xquery %}</pre></td>
 			<td>{% for arg, opt in  query.kwargs.iteritems %}
+				{% if arg = 'xquery' %} {# skip - already displayed #} {% else %}
 				{{ arg }}: {{ opt }}{% if not forloop.last %}<br/>{% endif %}
+				{% endif %}
 				{% endfor %}
 			</td>
 		</tr>