Closes netbox-community#2000: Remove support for Python 2

Author: jeremystretch

.travis.yml

@@ -5,7 +5,6 @@ addons:
   postgresql: "9.4"
 language: python
 python:
-  - "2.7"
   - "3.5"
 install:
   - pip install -r requirements.txt

README.md

@@ -16,8 +16,6 @@ or join us in the #netbox Slack channel on [NetworkToCode](https://networktocode
 
 ### Build Status
 
-NetBox is built against both Python 2.7 and 3.5. Python 3.5 or higher is strongly recommended.
-
 |             | status |
 |-------------|------------|
 | **master** | [![Build Status](https://travis-ci.org/digitalocean/netbox.svg?branch=master)](https://travis-ci.org/digitalocean/netbox) |

base_requirements.txt

@@ -1,5 +1,5 @@
 # django-filter-1.1.0 breaks with Django-2.1
-Django>=1.11,<2.1
+Django>=2.0,<2.1
 django-cors-headers
 django-debug-toolbar
 # django-filter-2.0.0 drops Python 2 support (blocked by #2000)

docs/additional-features/netbox-shell.md

@@ -9,7 +9,7 @@ This will launch a customized version of [the built-in Django shell](https://doc
 ```
 $ ./manage.py nbshell
 ### NetBox interactive shell (jstretch-laptop)
-### Python 2.7.6 | Django 1.11.3 | NetBox 2.1.0-dev
+### Python 3.5.2 | Django 2.0.8 | NetBox 2.4.3
 ### lsmodels() will show available models. Use help(<model>) for more info.
 ```
 

docs/installation/upgrading.md

@@ -64,13 +64,6 @@ Once the new code is in place, run the upgrade script (which may need to be run
 # ./upgrade.sh
 ```
 
-!!! warning
-    The upgrade script will prefer Python3 and pip3 if both executables are available. To force it to use Python2 and pip, use the `-2` argument as below. Note that Python 2 will no longer be supported in NetBox v2.5.
-
-```no-highlight
-# ./upgrade.sh -2
-```
-
 This script:
 
 * Installs or upgrades any new required Python packages

netbox/extras/reports.py

@@ -4,7 +4,6 @@
 import importlib
 import inspect
 import pkgutil
-import sys
 
 from django.conf import settings
 from django.utils import timezone
@@ -26,22 +25,12 @@ def get_report(module_name, report_name):
     """
     file_path = '{}/{}.py'.format(settings.REPORTS_ROOT, module_name)
 
-    # Python 3.5+
-    if sys.version_info >= (3, 5):
-        spec = importlib.util.spec_from_file_location(module_name, file_path)
-        module = importlib.util.module_from_spec(spec)
-        try:
-            spec.loader.exec_module(module)
-        except FileNotFoundError:
-            return None
-
-    # Python 2.7
-    else:
-        import imp
-        try:
-            module = imp.load_source(module_name, file_path)
-        except IOError:
-            return None
+    spec = importlib.util.spec_from_file_location(module_name, file_path)
+    module = importlib.util.module_from_spec(spec)
+    try:
+        spec.loader.exec_module(module)
+    except FileNotFoundError:
+        return None
 
     report = getattr(module, report_name, None)
     if report is None:

netbox/netbox/settings.py

@@ -7,21 +7,20 @@
 from django.contrib.messages import constants as messages
 from django.core.exceptions import ImproperlyConfigured
 
+# Check for Python 3.5+
+if sys.version_info < (3, 5):
+    raise RuntimeError(
+        "NetBox requires Python 3.5 or higher (current: Python {})".format(sys.version.split()[0])
+    )
+
+# Check for configuration file
 try:
     from netbox import configuration
 except ImportError:
     raise ImproperlyConfigured(
         "Configuration file is not present. Please define netbox/netbox/configuration.py per the documentation."
     )
 
-# Raise a deprecation warning for Python 2.x
-if sys.version_info[0] < 3:
-    warnings.warn(
-        "Support for Python 2 will be removed in NetBox v2.5. Please consider migration to Python 3 at your earliest "
-        "opportunity. Guidance is available in the documentation at http://netbox.readthedocs.io/.",
-        DeprecationWarning
-    )
-
 VERSION = '2.4.4-dev'
 
 BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))

netbox/utilities/middleware.py

@@ -72,11 +72,7 @@ def process_exception(self, request, exception):
             custom_template = 'exceptions/programming_error.html'
         elif isinstance(exception, ImportError):
             custom_template = 'exceptions/import_error.html'
-        elif (
-            sys.version_info[0] >= 3 and isinstance(exception, PermissionError)
-        ) or (
-            isinstance(exception, OSError) and exception.errno == 13
-        ):
+        elif isinstance(exception, PermissionError):
             custom_template = 'exceptions/permission_error.html'
 
         # Return a custom error message, or fall back to Django's default 500 error handling

requirements.txt

@@ -1,4 +1,4 @@
-Django>=1.11,<2.1
+Django>=2.0,<2.1
 django-cors-headers==2.4.0
 django-debug-toolbar==1.9.1
 django-filter==1.1.0

upgrade.sh

@@ -5,24 +5,8 @@
 # Once the script completes, remember to restart the WSGI service (e.g.
 # gunicorn or uWSGI).
 
-# Determine which version of Python/pip to use. Default to v3 (if available)
-# but allow the user to force v2.
 PYTHON="python3"
 PIP="pip3"
-type $PYTHON >/dev/null 2>&1 && type $PIP >/dev/null 2>&1 || PYTHON="python" PIP="pip"
-while getopts ":2" opt; do
-    case $opt in
-        2)
-            PYTHON="python"
-            PIP="pip"
-            echo "Forcing Python/pip v2"
-            ;;
-        \?)
-            echo "Invalid option: -$OPTARG" >&2
-            exit
-            ;;
-    esac
-done
 
 # Optionally use sudo if not already root, and always prompt for password
 # before running the command