Add function to pretty print HttpRequest

Make it easy to dump the contents of a view's HttpRequest to a logger.

Author: hmpf

python/nav/django/utils.py

@@ -18,6 +18,7 @@
 """Utility methods for django used in NAV"""
 
 from django.core.exceptions import FieldDoesNotExist
+from django.http import HttpRequest
 from django.urls import reverse
 from django.utils.http import urlencode
 
@@ -56,6 +57,39 @@ def get_verbose_name(model, lookup):
     raise FieldDoesNotExist
 
 
+def pp_request(request: HttpRequest, function, *attributes) -> None:
+    """View ``request`` via `function``, one line per attribute
+
+    Use the ``attributes`` parameter to limit what attributes are inspected.
+
+    Also dumps the contents of the dicts ``request.environ``and
+    ``request.META``, one line per value, sorted per key.
+
+    The ``function`` must have an input signature compatible with
+    ``logging.Logger.debug()``.
+
+    Meant for debugging via logs.
+
+    Example usage::
+
+        pp_request(request, logging.getLogger(__name__).debug)
+    """
+    DICT_ATTRIBUTES = ('META', 'environ')
+
+    existing_attributes = vars(request).keys()
+    if attributes:
+        attributes = set(existing_attributes).intersection(attributes)
+    else:
+        attributes = existing_attributes
+    for attribute in sorted(attributes):
+        value = getattr(request, attribute)
+        if attribute in DICT_ATTRIBUTES:
+            for key in sorted(value.keys()):
+                function('request.%s: %s: %s', attribute, key, value[key])
+        else:
+            function('request.%s: %s', attribute, value)
+
+
 #
 # Django version differentiated helper functions:
 #