Add script to update feeds

3 files changed, 220 insertions, 0 deletions

diff --git a/admin/feeds/build-feed.py b/admin/feeds/build-feed.py
new file mode 100755
index 0000000..5fe5c04
--- /dev/null
+++ b/admin/feeds/build-feed.py
@@ -0,0 +1,186 @@
+#!/usr/bin/env python3
+
+from datetime import datetime
+import json
+import re
+from sys import argv
+from urllib.parse import urljoin
+
+from lxml.builder import E
+from lxml.etree import CDATA, XML, indent, tostring
+
+from helpers import (
+    DATE_FORMATTERS,
+    guess_language,
+    read_concerts,
+    tmplocale,
+    touchup_plaintext,
+)
+
+
+# TODO: handle timezones correctly.
+# Places to disambiguate:
+#
+# - concerts.in:
+#   either add the zone explicitly, or deduce it from the place,
+#   assuming all times in concerts.in are local times.
+#
+# - concerts-pubdates.json:
+#   just add the zone explicitly.
+#
+# Until then, assume all these "naive times" describe the same timezone
+# (CET/CEST).
+
+
+TIMEZONE = datetime.now().astimezone().tzinfo
+NOW = datetime.now(tz=TIMEZONE)
+DATE_FORMAT = '%-d %b %Y %H:%M %z'
+
+# TODO: add item pubDate
+
+
+LOCALIZED_TEXT = {
+    'en': {
+        'title': 'Bellefeuille Quartet',
+        'indexpath': 'en/',
+        'description': 'News from the Bellefeuille quartet',
+    },
+    'fr': {
+        'title': 'Quatuor Bellefeuille',
+        'indexpath': '/',
+        'description': 'Des nouvelles du quatuor Bellefeuille',
+    },
+}
+
+LOCALIZED_FORMATS = {
+    'en': {
+        'title': lambda c: f'{c.time.strftime("%B %-d %Y")} in {c.place}',
+    },
+    'fr': {
+        'title': lambda c: f'{c.time.strftime("%-d %B %Y")} à {c.place}',
+    },
+}
+
+
+def join(sequence, joiner_factory):
+    # There's got to be a standard itertools/functools thingy to do that…
+    result = []
+
+    for i, item in enumerate(sequence, start=1):
+        result.append(item)
+
+        if i == len(sequence):
+            return result
+
+        result.append(joiner_factory())
+
+
+CDATA_INDENT = 8*' '
+
+
+def cdata_concert(concert, lang):
+    formatters = DATE_FORMATTERS[lang]
+
+    blocks = []
+
+    if concert.warning is not None:
+        blocks.append(E.p(concert.warning))
+
+    with tmplocale(lang):
+        blocks.extend((
+            E.p(formatters['date'](concert.time)),
+            E.p(formatters['time'](concert.time)),
+        ))
+
+    blocks.extend((
+        E.p(*join(concert.address.splitlines(), E.br)),
+        E.ol(
+            *(XML(f'<li>{touchup_plaintext(p)}</li>')
+              for p in concert.pieces.splitlines())
+        ),
+        *(E.p(line) for line in concert.instructions.splitlines()),
+    ))
+
+    for b in blocks:
+        indent(b)
+
+    html_blocks = (tostring(b, encoding='utf-8').decode() for b in blocks)
+
+    cdata = '\n' + '\n'.join(html_blocks) + '\n'
+    cdata = re.sub('^', CDATA_INDENT, cdata, flags=re.MULTILINE)
+
+    return CDATA(cdata)
+
+
+def generate_concert(concert, concerts_url, pubdates, lang):
+    formatters = LOCALIZED_FORMATS[lang]
+
+    with tmplocale(lang):
+        title = formatters['title'](concert)
+
+    anchor = f'concert-{concert.time.strftime("%F")}'
+
+    item = E.item(
+        E.title(title),
+        E.link(f'{concerts_url}#{anchor}'),
+        E.description(cdata_concert(concert, lang)),
+    )
+
+    pubdate_str = pubdates[concert.time.isoformat(timespec='minutes')]
+
+    if pubdate_str is not None:
+        pubdate = datetime.fromisoformat(pubdate_str).replace(tzinfo=TIMEZONE)
+        item.append(E.pubDate(pubdate.strftime(DATE_FORMAT)))
+
+    return item
+
+
+def generate_concerts(concerts_src, concerts_url, concerts_pubdates, lang):
+    with open(concerts_pubdates) as pubdates_file:
+        pubdates = json.load(pubdates_file)
+
+    return tuple(
+        generate_concert(c, concerts_url, pubdates, lang)
+        for c in read_concerts(concerts_src)
+    )
+
+
+def main(concerts_src, feed_dst, concerts_pubdates, domain):
+    lang = guess_language(concerts_src)
+    text = LOCALIZED_TEXT[lang]
+
+    url = f'https://{domain}'
+    index_url = urljoin(url, text['indexpath'])
+    concerts_url = urljoin(index_url, 'concerts.html')
+
+    now_formatted = NOW.strftime(DATE_FORMAT)
+
+    concerts = generate_concerts(
+        concerts_src, concerts_url, concerts_pubdates, lang
+    )
+
+    rss = E.rss(
+        E.channel(
+            E.title(text['title']),
+            E.link(index_url),
+            E.description(text['description']),
+            E.image(
+                E.url(urljoin(url, 'images/logo.svg')),
+                E.link(concerts_url),
+            ),
+            E.lastBuildDate(now_formatted),
+            E.pubDate(now_formatted),
+            E.language(lang),
+            *concerts,
+        ),
+        version='2.0',
+    )
+
+    indent(rss)
+
+    with open(feed_dst, 'wb') as feed:
+        feed.write(tostring(rss, encoding='utf-8', xml_declaration=True))
+
+
+if __name__ == '__main__':
+    main(*argv[1:])
diff --git a/admin/feeds/build-feeds.sh b/admin/feeds/build-feeds.sh
new file mode 100755
index 0000000..99b4a6e
--- /dev/null
+++ b/admin/feeds/build-feeds.sh
@@ -0,0 +1,19 @@
+#!/bin/bash
+
+set -eu
+
+HERE=$(dirname "$0")
+ROOT=${HERE}/../..
+
+. "${ROOT}"/settings.sh
+
+FEEDS=("$@")
+
+for feed in "${FEEDS[@]}"
+do
+    concert=$(dirname "${feed}")/concerts.in
+
+    PYTHONPATH="${ROOT}"                                                \
+    "${HERE}"/build-feed.py "${concert}" "${feed}"                      \
+                            "${HERE}"/concerts-pubdates.json ${domain}
+done
diff --git a/admin/feeds/concerts-pubdates.json b/admin/feeds/concerts-pubdates.json
new file mode 100644
index 0000000..4232ed7
--- /dev/null
+++ b/admin/feeds/concerts-pubdates.json
@@ -0,0 +1,15 @@
+{
+    "2019-10-05T17:00": null,
+    "2019-10-06T16:00": null,
+    "2020-03-08T16:00": null,
+    "2020-08-24T20:00": null,
+    "2021-04-03T20:00": "2021-03-19T16:00",
+    "2021-06-13T15:00": "2021-03-19T16:00",
+    "2021-08-17T20:30": null,
+    "2021-08-19T20:00": null,
+    "2021-10-25T18:00": null,
+    "2021-10-28T18:00": null,
+    "2021-12-12T16:00": "2021-11-23T23:28",
+    "2021-12-31T20:00": null,
+    "2022-05-07T17:00": null
+}