ext/django: django downgrade to 1.10 (#717)

Adding support for django 1.10+

Author: HiveTraum

ext/opentelemetry-ext-django/setup.cfg

@@ -28,17 +28,19 @@ classifiers =
     License :: OSI Approved :: Apache Software License
     Programming Language :: Python
     Programming Language :: Python :: 3
+    Programming Language :: Python :: 3.4
+    Programming Language :: Python :: 3.5
     Programming Language :: Python :: 3.6
     Programming Language :: Python :: 3.7
     Programming Language :: Python :: 3.8
 
 [options]
-python_requires = >=3.6
+python_requires = >=3.4
 package_dir=
     =src
 packages=find_namespace:
 install_requires =
-    django >= 2.2
+    django >= 1.10
     opentelemetry-ext-wsgi == 0.8.dev0
     opentelemetry-auto-instrumentation == 0.8.dev0
     opentelemetry-api == 0.8.dev0

ext/opentelemetry-ext-django/src/opentelemetry/ext/django/middleware.py

@@ -14,8 +14,6 @@
 
 from logging import getLogger
 
-from django.utils.deprecation import MiddlewareMixin
-
 from opentelemetry.context import attach, detach
 from opentelemetry.ext.django.version import __version__
 from opentelemetry.ext.wsgi import (
@@ -26,6 +24,11 @@
 from opentelemetry.propagators import extract
 from opentelemetry.trace import SpanKind, get_tracer
 
+try:
+    from django.utils.deprecation import MiddlewareMixin
+except ImportError:
+    MiddlewareMixin = object
+
 _logger = getLogger(__name__)
 
 

tox.ini

@@ -29,7 +29,7 @@ envlist =
     pypy3-test-ext-aiohttp-client
 
     ; opentelemetry-ext-django
-    py3{6,7,8}-test-ext-django
+    py3{4,5,6,7,8}-test-ext-django
     pypy3-test-ext-django
 
     ; opentelemetry-ext-dbapi