From 66579e2375069a7f301bde62df821625c3060209 Mon Sep 17 00:00:00 2001 From: putro Date: Fri, 26 Apr 2019 13:17:34 +0200 Subject: [PATCH] added events plugin to generate a calendar.ics ical file --- pelicanconf.py | 7 ++ plugins/events-readme.md | 88 ++++++++++++++++ plugins/events.py | 212 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 307 insertions(+) create mode 100644 plugins/events-readme.md create mode 100644 plugins/events.py diff --git a/pelicanconf.py b/pelicanconf.py index c0c094d..75b2ce9 100644 --- a/pelicanconf.py +++ b/pelicanconf.py @@ -32,6 +32,13 @@ TRANSLATION_FEED_ATOM = None AUTHOR_FEED_ATOM = None AUTHOR_FEED_RSS = None +PLUGIN_PATHS = ['plugins/'] +PLUGINS = ['events'] + +PLUGIN_EVENTS = { + 'ics_fname': 'calendar.ics', +} + LINKS = None SOCIAL = None diff --git a/plugins/events-readme.md b/plugins/events-readme.md new file mode 100644 index 0000000..7a9b51f --- /dev/null +++ b/plugins/events-readme.md @@ -0,0 +1,88 @@ +Events plugin +============= + +This plugin allows you to put events in your content via metadata. An +iCal file is generated containing all events. + + +Dependencies +------------ + +This plugin depends on the `icalendar` package, which can be installed +using APT, DNF/YUM or pip: + +```sh +pip install icalendar +``` + + +Settings +-------- + +You can define settings with the `PLUGIN_EVENTS` variable: + +```python +PLUGIN_EVENTS = { + 'ics_fname': 'calendar.ics', +} +``` + +Settings: +- `ics_fname`: Where the iCal file is written + + +Usage +----- + +You can use the following metadata in your content: +- `event-start`: When the event will start in "YYYY-MM-DD hh:mm" +- `event-end`: When the event will stop in "YYYY-MM-DD hh:mm" +- `event-duration`: The duration of the event [1] +- `event-location`: Where the event takes place +- `event-recurring`: weekly until 2020-12-21 + +[1] To specify the event duration, use a number followed by a time unit: +- `w`: weeks +- `d`: days +- `h`: hours +- `m`: minutes +- `s`: seconds + +You can also add recurring events by setting the ‘event-recurring’ setting. +Use ‘daily’, ‘weekly’, ‘monthly’ or ‘yearly’. +These will continue until a set end date in “YYYY-MM-DD hh:mm” format. + + +Examples +-------- + +Example in reST format: +```reST +:event-start: 2015-01-21 10:30 +:event-duration: 2h +:event-location: somewhere +``` + +Example in Markdown format: +```markdown +Event-start: 2015-01-21 10:30 +Event-duration: 2h +Event-location: somewhere +``` + + +Dedicated page +-------------- + +To generate a sorted event list in its own dedicated page: +- Copy the `events_list.html` template under the templates directory of your theme +- Create a page for this list, for example in `content/pages/events_list.rst` +- Include the following metadata in your content: +```reST +Events list +########### +:slug: events-list +:summary: +:template: events_list +``` + diff --git a/plugins/events.py b/plugins/events.py new file mode 100644 index 0000000..43ed606 --- /dev/null +++ b/plugins/events.py @@ -0,0 +1,212 @@ +# -*- coding: utf-8 -*- +""" +events plugin for Pelican +========================= + +This plugin looks for and parses an "events" directory and generates +blog posts with a user-defined event date. (typically in the future) +It also generates an ICalendar v2.0 calendar file. +https://en.wikipedia.org/wiki/ICalendar + + +Author: Federico Ceratto +Released under AGPLv3+ license, see LICENSE +""" + +from datetime import datetime, timedelta +from pelican import signals, utils +from collections import namedtuple, defaultdict +import icalendar +import logging +import os.path +import pytz + +log = logging.getLogger(__name__) + +TIME_MULTIPLIERS = { + 'w': 'weeks', + 'd': 'days', + 'h': 'hours', + 'm': 'minutes', + 's': 'seconds' +} + +events = [] +localized_events = defaultdict(list) +Event = namedtuple("Event", "dtstart dtend metadata rrule") + + +def parse_tstamp(ev, field_name): + """Parse a timestamp string in format "YYYY-MM-DD HH:MM" + + :returns: datetime + """ + try: + return datetime.strptime(ev[field_name], '%Y-%m-%d %H:%M') + except Exception as e: + log.error("Unable to parse the '%s' field in the event named '%s': %s" \ + % (field_name, ev['title'], e)) + raise + +def parse_timedelta(ev): + """Parse a timedelta string in format [ ]* + e.g. 2h 30m + + :returns: timedelta + """ + + chunks = ev['event-duration'].split() + tdargs = {} + for c in chunks: + try: + m = TIME_MULTIPLIERS[c[-1]] + val = int(c[:-1]) + tdargs[m] = val + except KeyError: + log.error("""Unknown time multiplier '%s' value in the \ +'event-duration' field in the '%s' event. Supported multipliers \ +are: '%s'.""" % (c, ev['title'], ' '.join(TIME_MULTIPLIERS))) + raise RuntimeError("Unknown time multiplier '%s'" % c) + except ValueError: + log.error("""Unable to parse '%s' value in the 'event-duration' \ +field in the '%s' event.""" % (c, ev['title'])) + raise ValueError("Unable to parse '%s'" % c) + + + return timedelta(**tdargs) + +def parse_recursion(ev, field_name): + """ + Parse information about recurring events and return frequency of event and untill time. + """ + chunks = ev[field_name].split() + freq = chunks[0].upper() + if 'until' in chunks: + until = datetime.strptime(chunks[-1], '%Y-%m-%d') + rrule = [freq, until] + else: + rrule = [freq] + return rrule + +def parse_article(generator, metadata): + """Collect articles metadata to be used for building the event calendar + + :returns: None + """ + if 'event-start' not in metadata: + return + + dtstart = parse_tstamp(metadata, 'event-start') + rrule=[] + if 'event-end' in metadata: + dtend = parse_tstamp(metadata, 'event-end') + + elif 'event-duration' in metadata: + dtdelta = parse_timedelta(metadata) + dtend = dtstart + dtdelta + + if 'event-recurring' in metadata: + rrule = parse_recursion(metadata, 'event-recurring') + + else: + msg = "Either 'event-end' or 'event-duration' must be" + \ + " speciefied in the event named '%s'" % metadata['title'] + log.error(msg) + raise ValueError(msg) + + events.append(Event(dtstart, dtend, metadata, rrule)) + + +def generate_ical_file(generator): + """Generate an iCalendar file + """ + global events + + ics_fname = generator.settings['PLUGIN_EVENTS']['ics_fname'] + if not ics_fname: + return + + ics_fname = os.path.join(generator.settings['OUTPUT_PATH'], ics_fname) + log.debug("Generating calendar at %s with %d events" % (ics_fname, len(events))) + + tz = generator.settings.get('TIMEZONE', 'UTC') + tz = pytz.timezone(tz) + + ical = icalendar.Calendar() + ical.add('prodid', '-//My calendar product//mxm.dk//') + ical.add('version', '2.0') + + DEFAULT_LANG = generator.settings['DEFAULT_LANG'] + curr_events = events if not localized_events else localized_events[DEFAULT_LANG] + for e in curr_events: + + #force convert to ical format here, because otherwise it doesn't happen? + from icalendar import vDatetime as vd + dtend = vd(e.dtend).to_ical() + dtstart = vd(e.dtstart).to_ical() + dtstamp = vd (e.metadata['date']).to_ical() + + ie = icalendar.Event( + summary=e.metadata['title'], + dtstart=dtstart, + dtend=dtend, + dtstamp= dtstamp, + priority=5, + uid=e.metadata['title'], + ) + if 'event-location' in e.metadata: + ie.add('location', e.metadata['event-location']) + + if 'event-recurring' in e.metadata: + if len(e.rrule)>=2: + ie.add('rrule', {'freq':e.rrule[0],'until':e.rrule[1]}) + else: + ie.add('rrule', {'freq':e.rrule[0]}) + + ical.add_component(ie) + with open(ics_fname, 'wb') as f: + f.write(ical.to_ical()) + + +def generate_localized_events(generator): + """ Generates localized events dict if i18n_subsites plugin is active """ + + if "i18n_subsites" in generator.settings["PLUGINS"]: + if not os.path.exists(generator.settings['OUTPUT_PATH']): + os.makedirs(generator.settings['OUTPUT_PATH']) + + for e in events: + if "lang" in e.metadata: + localized_events[e.metadata["lang"]].append(e) + else: + log.debug("event %s contains no lang attribute" % (e.metadata["title"],)) + + +def generate_events_list(generator): + """Populate the event_list variable to be used in jinja templates""" + + if not localized_events: + generator.context['events_list'] = sorted(events, reverse = True, + key=lambda ev: (ev.dtstart, ev.dtend)) + else: + generator.context['events_list'] = {k: sorted(v, reverse = True, + key=lambda ev: (ev.dtstart, ev.dtend)) + for k, v in localized_events.items()} + +def initialize_events(article_generator): + """ + Clears the events list before generating articles to properly support plugins with + multiple generation passes like i18n_subsites + """ + + del events[:] + localized_events.clear() + +def register(): + signals.article_generator_init.connect(initialize_events) + signals.article_generator_context.connect(parse_article) + signals.article_generator_finalized.connect(generate_localized_events) + signals.article_generator_finalized.connect(generate_ical_file) + signals.article_generator_finalized.connect(generate_events_list) + +