➖ Remove python-dateutil dependency

It's no longer installable from source under OctoPi 0.14 due to an
unpinned setup_requires dependency on setuptools_scm, and since we still
have to support that installation scenario that is a problem. Thankfully
it's only used in the plugin manager for parsing the notice date, and
we can just use datetime.strptime for that.

Author: foosel

THIRDPARTYLICENSES.md

@@ -36,7 +36,6 @@
   * [Awesome-Slugify](https://pypi.python.org/pypi/awesome-slugify): GPLv3
   * [chainmap](https://bitbucket.org/jeunice/chainmap): Python
   * [Click](http://click.pocoo.org/): BSD
-  * [dateutil](https://dateutil.readthedocs.io/): BSD
   * [emoji](https://github.com/carpedm20/emoji/): BSD
   * [feedparser](https://github.com/kurtmckee/feedparser): BSD
   * [Flask](http://flask.pocoo.org/): BSD

setup.py

@@ -20,13 +20,13 @@
 	# the following dependencies are non trivial to update since later versions introduce backwards incompatible
 	# changes that might affect plugins, or due to other observed problems
 
-	"flask>=0.10.1,<0.11",       # newer versions require newer Jinja versions
-	"Jinja2>=2.8.1,<2.9",        # Jinja 2.9 has breaking changes WRT template scope - we can't
-	                             # guarantee backwards compatibility for plugins and such with that
-	                             # version, hence we need to pin to a lower version for now. See #1697
-	"tornado==4.5.3",            # a memory leak was observed in tornado >= 5, see #2585
-	"Flask-Login>=0.2.11,<0.3",  # some functions changed to properties in 0.3
-	"regex!=2018.11.6",          # avoid broken 2018.11.6. See #2874
+	"flask>=0.10.1,<0.11",         # newer versions require newer Jinja versions
+	"Jinja2>=2.8.1,<2.9",          # Jinja 2.9 has breaking changes WRT template scope - we can't
+	                               # guarantee backwards compatibility for plugins and such with that
+	                               # version, hence we need to pin to a lower version for now. See #1697
+	"tornado==4.5.3",              # a memory leak was observed in tornado >= 5, see #2585
+	"Flask-Login>=0.2.11,<0.3",    # some functions changed to properties in 0.3
+	"regex!=2018.11.6",            # avoid broken 2018.11.6. See #2874
 
 	# anything below this should be checked on releases for new versions
 
@@ -55,7 +55,6 @@
 	"future>=0.17.1,<0.18",
 	"scandir>=1.10,<1.11",
 	"websocket-client>=0.56,<0.57",
-	"python-dateutil>=2.8,<2.9",
 	"wrapt>=1.11.1,<1.12",
 	"futures>=3.2,<3.3",
 	"emoji>=0.5.1,<0.6",

src/octoprint/plugins/pluginmanager/__init__.py

@@ -28,10 +28,11 @@
 import re
 import os
 import copy
-import dateutil.parser
 import time
 import threading
 
+from datetime import datetime
+
 _DATA_FORMAT_VERSION = "v2"
 
 
@@ -868,7 +869,12 @@ def _refresh_notices(self, notice_data=None):
 			key = notice["plugin"]
 
 			try:
-				parsed_date = dateutil.parser.parse(notice["date"])
+				# Jekyll turns "%Y-%m-%d %H:%M:%SZ" into "%Y-%m-%d %H:%M:%S +0000", so be sure to ignore "+0000"
+				#
+				# Being able to use dateutil here would make things way easier but sadly that can no longer get
+				# installed (from source) under OctoPi 0.14 due to its setuptools-scm dependency, so we have to do
+				# without it for now until we can drop support for OctoPi 0.14.
+				parsed_date = datetime.strptime(notice["date"], "%Y-%m-%d %H:%M:%S +0000")
 				notice["timestamp"] = parsed_date.timetuple()
 			except Exception as e:
 				self._logger.warn("Error while parsing date {!r} for plugin notice "