termine.md now gets default data; also lots of bugfixes around dates and times

content/pages/termine.md.metadata

@@ -0,0 +1,9 @@
+title: Termine 
+author: Tobias Radloff
+summary: Lesungen und Veranstaltungen
+template: termine.noformat
+lang: de
+category: Termine
+slug: termine
+url: termine/
+save_as: termine/index.html

pelicanconf.py

@@ -8,6 +8,10 @@ SITESUBTITLE = "Schriftsteller"
 SITEURL = ""
 
 TIMEZONE = 'Europe/Berlin'
+DATE_FORMATS = {
+  'de': '%a, %d. %b %y',
+  'en': '%Y-%m-%d(%a)',
+}
 DEFAULT_LANG = 'de'
 
 THEME = "theme/"
@@ -22,7 +26,7 @@ PAGE_PATHS = ["pages"]
 STATIC_PATHS = ["images", "favicon"]
 
 DIRECT_TEMPLATES = ['index', 'tags']
-IGNORE_FILES = ['**/.*', '__pycache__', 'favicon-from-svg.sh']
+IGNORE_FILES = ['**/.*', '__pycache__', 'favicon-from-svg.sh', '*.metadata']
 
 EXTRA_PATH_METADATA = {
     'favicon/favicon.ico': {'path': 'favicon.ico'},

utils/refresh-events.py

@@ -1,15 +1,25 @@
 import caldav
 import vobject
-from datetime import datetime, date, time
+from datetime import datetime, date, time, timedelta
 import yaml
+import os
 
+import locale
+import threading
+from contextlib import contextmanager
+
+
+"""CalDAV server url"""
 server_url = "https://***REMOVED***
-cal_user = "tobias"
+"""CalDAV calendar url"""
 cal_url = "https://***REMOVED***
+"""CalDAV username"""
+cal_user = "tobias"
+"""Category to filter events for. Only events that belong to this category will be processed."""
 cal_category = "Veranstaltung"
+"""Name of the file the YAML data will be writte to.""" 
 result_file = "../content/pages/termine.md"
-now = datetime.now().astimezone()
-
+"""List of icalendar properties that will be passed on to Pelican. At this time, all properties are used except those regarding alarms.""" 
 cal_properties = [ # taken from ical specification
   # descriptive  
   "attach", "categories", "class", "comment", "description", "geo", "location", "percent-complete", "priority", "resources", "status", "summary",
@@ -26,10 +36,13 @@ cal_properties = [ # taken from ical specification
   # change management
   "created", "dtstamp", "last-modified", "sequence"
 ]
+"""List of icalendar properties that the vobject passes as either datetime.datetime or datetime.date objects. To be able to compare any two objects, the script makes each one aware and/or converts into datetime.datetime if necessary. Default timezone is the system timezone; default time is 23:59:59."""  
 cal_prop_datetimes = ["dtend", "due", "dtstart", "duration", "dtstamp", "last-modified"]
+"""Current time as an aware datetime.datetime object.""" 
+now = datetime.now().astimezone()
 
 
-"""Converts a datetime.datetime or datetime.date object into an aware datetime object."""
+"""Returns an aware datetime.datetime object based on the given datetime or date. Conversion happens only if necessary, i.e. if d is of type datetime.date or a naive datetime.datetime object."""
 def fixDatetime(d, t=None, tz=None):
   if not tz:
     tz = now.tzinfo
@@ -53,6 +66,30 @@ def fixDatetime(d, t=None, tz=None):
   return datetime.combine(d, t)
 
 
+"""Takes a list of events in vobject representation and converts each event into a dict of Python datatypes.""" 
+def extractEventData(events):
+  e_tmp = []
+
+  # iterate over events
+  for e in events:
+    d = {}
+
+    # iterate over event properties
+    for k, v in e.contents.items():
+      # we're only interested in a subset of properties
+      if not k in cal_properties:
+        continue
+
+      # Usually, v is a list with a single item. We only need the item's value attribute 
+      if len(v) == 1:
+        d[k] = v[0].value
+      # but sometimes the list has more than one item; this only ever happens for the property "categories"
+      # and in this case, each list item's value is itself a one item list (which is stupid but that's how vobject handles categories)
+      else:
+        d[k] = [v[i].value[0] for i in range(len(v))]
+    e_tmp.append(d)
+  return e_tmp
+
 # get password
 with open(".caldav_pass", "r") as f:
   cal_pass = f.read().strip()
@@ -73,29 +110,17 @@ with caldav.DAVClient(url=server_url, username=cal_user, password=cal_pass) as d
 # we only want events belonging to a specific category 
 events = [e for e in vcal.getChildren() if "categories" in e.contents.keys() and cal_category in map(lambda x: x.value[0], e.contents["categories"])]
 
-# convert events into a structure suitable for Pelican 
-e_tmp = []
-for e in events:
-  d = {}
-  for k, v in e.contents.items():
-    # only keep specific calendar properties
-    if not k in cal_properties:
-      continue
-
-    # v is usually a list with a single item 
-    if len(v) == 1:
-      d[k] = v[0].value
-    # but sometimes there's more than one item (this only ever happens when k is "categories")
-    # and in this case, each list item's value is itself a one item list (which is stupid but that's how vobject handles categories)
-    else:
-      d[k] = [v[i].value[0] for i in range(len(v))]
-  e_tmp.append(d)
-events = e_tmp
+# extract event data 
+events = extractEventData(events)
 
 # fix dates and datetimes
 for e in events:
   for k in e.keys():
     if k in cal_prop_datetimes:
+      # fix a CalDAV/vobject/icalendar (?) bug where a dtend value which is a date only (no time) automatically moves one day into the future 
+      if k == "dtend" and type(e[k]) == date:
+        e[k] = e[k] - timedelta(days=1)
+      # fix all datetimes so they can be compared and sorted 
       e[k] = fixDatetime(e[k])
 
 # keep only future events  
@@ -104,9 +129,46 @@ events = [e for e in events if e["dtstart"] >= now]
 # sort by start date
 events.sort(key=lambda e: e["dtstart"])
 
+# read default metadata if present
+default_metadata = None
+if os.path.isfile(result_file + ".metadata"):
+  with open(result_file + ".metadata", "r") as f:
+    default_metadata = yaml.safe_load(f)
+
+# set up a context manager in order to threadsafely format dates and times with the German locale 
+# source: https://stackoverflow.com/a/24070673
+LOCALE_LOCK = threading.Lock()
+
+@contextmanager
+def setlocale(name):
+  with LOCALE_LOCK:
+    saved = locale.setlocale(locale.LC_TIME)
+    try:
+      yield locale.setlocale(locale.LC_TIME, name)
+    finally:
+      locale.setlocale(locale.LC_TIME, saved)
+
+# temporary set locale to de_DE (category "time" only) and format start date as well as start time or end date
+with setlocale('de_DE.UTF-8'):
+  for e in events:
+    # start date
+    e["startdate"] = e["dtstart"].strftime("%a, %d.%m.")
+    # start time (if not the default time)
+    if e["dtstart"].timetz() != time(23, 59, 59, tzinfo=now.tzinfo):
+      e["starttime"] = e["dtstart"].strftime("%H:%M Uhr")
+    # end date (if different from start date)
+    if e["dtstart"].date() < e["dtend"].date():
+      e["enddate"] = e["dtend"].date().strftime("%a, %d.%m.")
+
+  # add current date to default metadata while we're at it
+  if default_metadata:
+    default_metadata["date"] = now.strftime("%Y-%m-%d %H:%M")
+
 # write data as YAML
 with open(result_file, 'w') as f:
   f.write("---\n")
+  if default_metadata:
+    yaml.dump(default_metadata, f)
   yaml.dump({"termine": events}, f)
   f.write("---\n")
   f.write("written at " + datetime.today().isoformat(" "))