Initial commit

.gitignore

@@ -0,0 +1,5 @@
+*.py[c|o]
+__pycache__/
+.idea/
+*.*swp*
+docker-compose.yml

Dockerfile

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+FROM python:3.8-alpine
+
+RUN adduser -S fabcal
+
+RUN apk add --no-cache build-base libuv-dev libffi-dev && \
+    pip3 install poetry
+
+USER fabcal
+
+COPY poetry.lock pyproject.toml /app/
+
+WORKDIR /app/
+
+RUN pip install -U poetry && \
+    poetry install
+
+COPY main.py /app/
+COPY static/ /app/static/
+COPY templates/ /app/templates/
+
+ENTRYPOINT ["poetry", "run", "uvicorn", "main:app", "--host", "0.0.0.0", "--port", "5000", "--use-colors"]

LICENSE.txt

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+Copyright (C) 2022 by Fabian Müller <fabian@fablab-altmuehlfranken.de>
+
+Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.[20]

README.md

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+# FabCal
+
+Renders a web calendar, sanitizing the input and serving it from a static URL. Also renders HTML pages for embedding
+in homepages.

docker-compose.yml.example

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+version: "2"
+
+services:
+  fabcal:
+    build: .
+    restart: unless-stopped
+    ports:
+      - 5000:5000
+    environment:
+      - CALENDAR_URL=webcal://some.host/somecal
+    # use the line below when running this behind reverse proxy (only if it sets the proxy headers, though)
+    #command: --proxy-headers --forwarded-allow-ips="*"
+

main.py

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+import base64
+import locale
+import os
+from collections import OrderedDict
+
+from datetime import date, datetime, timedelta, timezone
+from typing import NamedTuple, List
+
+import aiohttp
+import babel.dates
+import recurring_ical_events
+
+from icalendar import Calendar, vText
+
+from fastapi import FastAPI
+from fastapi_cache import FastAPICache
+from fastapi_cache.backends.inmemory import InMemoryBackend
+from fastapi_cache.decorator import cache
+from fastapi.staticfiles import StaticFiles
+from fastapi.templating import Jinja2Templates
+from fastapi.requests import Request
+from fastapi.middleware.cors import CORSMiddleware
+from fastapi.responses import Response
+
+app = FastAPI()
+
+app.mount("/static", StaticFiles(directory="static"), name="static")
+
+templates = Jinja2Templates(directory="templates")
+
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=[
+        "https://fablab-altmuehlfranken.de",
+        "https://www.fablab-altmuehlfranken.de",
+    ],
+)
+
+
+locale.setlocale(locale.LC_TIME, locale.getlocale())
+
+
+def get_calendar_url():
+    url = os.environ["CALENDAR_URL"]
+
+    # convenience feature
+    url = url.replace("webcal://", "https://")
+
+    return url
+
+
+def sanitize(data: str):
+    # sanitize input from random source
+    cal = Calendar.from_ical(data)
+
+    # name needs to be fixed
+    cal["X-WR-CALNAME"] = vText(b"FabLab-Termine")
+
+    return cal.to_ical()
+
+
+# caching strings works better than caching calendar objects
+@cache(expire=120)
+async def get_data() -> str:
+    async with aiohttp.ClientSession() as session:
+        async with session.get(get_calendar_url()) as response:
+            response.raise_for_status()
+            assert response.content_type.lower() == "text/calendar"
+
+            return sanitize(await response.text())
+
+
+class CalendarEvent(NamedTuple):
+    start: datetime
+    end: datetime
+    # just a convenience thing, we want to keep start/date as datetime and save the client from guessing this themselves
+    all_day_event: bool
+    summary: str
+    description: str
+    location: str
+    color: str
+    uid: str
+
+
+def get_tzinfo():
+    return timezone(timedelta(hours=1))
+
+
+def get_events_from_calendar_string(cal: Calendar) -> List[CalendarEvent]:
+    """
+    Generate list of events from calendar vevents.
+    Expands recurring events for +- one year.
+    Note that there is no validation, e.g., checking for values required (by other code in this application).
+    :param cal: calendar to fetch events from
+    :return: events
+    """
+
+    now = datetime.now()
+    td = timedelta(days=365)
+    past_year = now - td
+    next_year = now + td
+
+    events = []
+
+    for vevent in recurring_ical_events.of(cal).between(past_year, next_year):
+        # I'm pessimistic here. Prove me wrong!
+        all_day_event = False
+
+        start = vevent.get("DTSTART", None)
+        if start is not None:
+            start = start.dt
+
+            if not isinstance(start, datetime):
+                all_day_event = True
+                start = datetime.combine(start, datetime.min.time(), tzinfo=get_tzinfo())
+
+        end = vevent.get("DTEND", None)
+        if end is not None:
+            end = end.dt
+
+            if not isinstance(end, datetime):
+                all_day_event = True
+                end = datetime.combine(end, datetime.max.time(), tzinfo=get_tzinfo())
+
+        def get_str(key: str):
+            value = vevent.get(key, None)
+
+            if value is not None:
+                return str(value)
+
+            return value
+
+        summary = get_str("SUMMARY")
+        description = get_str("DESCRIPTION")
+        location = get_str("LOCATION")
+        color = get_str("COLOR")
+        uid = get_str("UID")
+
+        event = CalendarEvent(start, end, all_day_event, summary, description, location, color, uid)
+        events.append(event)
+
+    events.sort(key=lambda e: e.start)
+
+    return events
+
+
+async def get_future_events():
+    cal = Calendar.from_ical(await get_data())
+
+    events = get_events_from_calendar_string(cal)
+
+    today = datetime.today().date()
+
+    future_events = []
+
+    for event in events:
+        if event.start.date() <= today:
+            continue
+
+        future_events.append(event)
+
+    return future_events
+
+
+@app.get("/events.ics")
+async def ics():
+    return Response(
+        await get_data(),
+        headers={
+            "content-type": "text/calendar",
+        },
+    )
+
+
+def group_by_date(events: List[CalendarEvent]):
+    grouped_events: OrderedDict[date, List[CalendarEvent]] = OrderedDict()
+
+    for event in events:
+        start_date = event.start.date()
+
+        if start_date not in grouped_events:
+            grouped_events[start_date] = []
+
+        grouped_events[start_date].append(event)
+
+    return grouped_events
+
+
+@app.get("/embed-sidebar.html")
+async def embed(request: Request, max_width: str = None):
+    # await asyncio.sleep(1)
+
+    events = await get_future_events()
+
+    grouped_events = list(group_by_date(events).items())
+
+    # couple of helpers
+    def localized_abbreviated_month(dt: datetime):
+        return babel.dates.format_datetime(dt, format="%b", locale="de_DE")
+
+    # couple of helpers
+    def localized_abbreviated_weekday(dt: datetime):
+        return babel.dates.format_datetime(dt, format="%b", locale="de_DE")
+
+    def base64_encode(s: str):
+        return base64.b64encode(s.encode()).decode()
+
+    return templates.TemplateResponse(
+        "embed-sidebar.html",
+        context={
+            "request": request,
+            "grouped_events": grouped_events,
+            "dir": dir,
+            "localized_abbreviated_month": localized_abbreviated_month,
+            "localized_abbreviated_weekday": localized_abbreviated_weekday,
+            "base64_encode": base64_encode,
+            "max_width": max_width,
+        },
+    )
+
+
+@app.on_event("startup")
+async def startup():
+    FastAPICache.init(InMemoryBackend())

pyproject.toml

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+[tool.poetry]
+name = "fabcal"
+version = "0.0.1"
+description = ""
+authors = ["Fabian Müller <fabian@fablab-altmuehlfranken.de>"]
+
+[tool.poetry.dependencies]
+python = "^3.8"
+icalendar = "^4.0.9"
+fastapi = "^0.75.0"
+uvicorn = {extras = ["standard"], version = "^0.17.6"}
+Jinja2 = "^3.1.0"
+Babel = "^2.9.1"
+fastapi-cache2 = "^0.1.8"
+aiohttp = {extras = ["speedups"], version = "^3.8.1"}
+recurring-ical-events = "^1.0.1-beta.0"
+
+[tool.poetry.dev-dependencies]
+black = "^22.1.0"
+
+[build-system]
+requires = ["poetry-core>=1.0.0"]
+build-backend = "poetry.core.masonry.api"
+
+[tool.black]
+line-length = 120

static/roboto.css

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+@font-face {
+    font-family: 'Roboto';
+    font-style: normal;
+    font-weight: 400;
+    src: url(https://static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-regular.eot);
+    src: local('Roboto'), local('Roboto-Regular'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-regular.eot?#iefix) format('embedded-opentype'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-regular.woff2) format('woff2'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-regular.woff) format('woff'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-regular.ttf) format('truetype'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-regular.svg#Roboto) format('svg')
+}
+
+@font-face {
+    font-family: 'Roboto';
+    font-style: italic;
+    font-weight: 400;
+    src: url(https://static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-italic.eot);
+    src: local('Roboto Italic'), local('Roboto-Italic'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-italic.eot?#iefix) format('embedded-opentype'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-italic.woff2) format('woff2'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-italic.woff) format('woff'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-italic.ttf) format('truetype'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-italic.svg#Roboto) format('svg')
+}
+
+@font-face {
+    font-family: 'Roboto';
+    font-style: normal;
+    font-weight: 700;
+    src: url(https://static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-700.eot);
+    src: local('Roboto Bold'), local('Roboto-Bold'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-700.eot?#iefix) format('embedded-opentype'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-700.woff2) format('woff2'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-700.woff) format('woff'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-700.ttf) format('truetype'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-700.svg#Roboto) format('svg')
+}
+
+@font-face {
+    font-family: 'Roboto';
+    font-style: italic;
+    font-weight: 700;
+    src: url(https://static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-700italic.eot);
+    src: local('Roboto Bold Italic'), local('Roboto-BoldItalic'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-700italic.eot?#iefix) format('embedded-opentype'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-700italic.woff2) format('woff2'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-700italic.woff) format('woff'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-700italic.ttf) format('truetype'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-v20-latin-700italic.svg#Roboto) format('svg')
+}
+
+@font-face {
+    font-family: 'Roboto Slab';
+    font-style: normal;
+    font-weight: 400;
+    src: url(https://static.fablab-altmuehlfranken.de/fonts/roboto-slab-v9-latin-regular.eot);
+    src: local('Roboto Slab Regular'), local('RobotoSlab-Regular'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-slab-v9-latin-regular.eot?#iefix) format('embedded-opentype'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-slab-v9-latin-regular.woff2) format('woff2'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-slab-v9-latin-regular.woff) format('woff'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-slab-v9-latin-regular.ttf) format('truetype'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-slab-v9-latin-regular.svg#RobotoSlab) format('svg')
+}
+
+@font-face {
+    font-family: 'Roboto Slab';
+    font-style: normal;
+    font-weight: 700;
+    src: url(https://static.fablab-altmuehlfranken.de/fonts/roboto-slab-v9-latin-700.eot);
+    src: local('Roboto Slab Bold'), local('RobotoSlab-Bold'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-slab-v9-latin-700.eot?#iefix) format('embedded-opentype'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-slab-v9-latin-700.woff2) format('woff2'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-slab-v9-latin-700.woff) format('woff'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-slab-v9-latin-700.ttf) format('truetype'), url(//static.fablab-altmuehlfranken.de/fonts/roboto-slab-v9-latin-700.svg#RobotoSlab) format('svg')
+}

static/style.css

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+:root {
+    --calendar-fablab-red: #D13F34;
+    --calendar-fablab-blue: #16A3C4;
+    --calendar-border: 1px solid #999;
+}
+
+body {
+    color: black;
+
+    /* inspired by fablab-altmuehlfranken.de */
+    font-weight: 100;
+    line-height: 1.3;
+    font-size: 9pt;
+
+    height: auto;
+    overflow: auto
+}
+
+.calendar {
+    width: 100%;
+    margin: 0 auto;
+}
+
+.calendar-date {
+    margin-bottom: 8px;
+    display: flex;
+    align-items: stretch;
+    flex-direction: row;
+    background-color: white;
+}
+
+.calendar-date-date {
+    border: var(--calendar-border);
+    text-align: center;
+    border-radius: 5px;
+    margin-right: 8px;
+    flex: 35px 0 0;
+    height: 100%;
+}
+.calendar-date-month {
+    background-color: var(--calendar-fablab-red);
+    color: white;
+    padding: 3px 0;
+}
+.calendar-date:nth-of-type(2n) .calendar-date-month {
+    /*background-color: var(--calendar-fablab-blue);*/
+}
+.calendar-date-day {
+    font-size: 13pt;
+    font-weight: 700;
+    padding-top: 3px;
+}
+.calendar-date-weekday {
+    padding-bottom: 3px;
+}
+
+.calendar-events {
+    flex-grow: 100;
+    vertical-align: top;
+}
+.calendar-event {
+    background-color: white;
+    border: var(--calendar-border);
+    border-radius: 5px;
+    padding: 5px;
+    margin-bottom: 5px;
+    filter: brightness(1);
+    display: flex;
+    align-items: stretch;
+    flex-direction: row;
+    justify-content: center;
+}
+.calendar-event-time {
+    text-align: center;
+    padding: 5px 8px 5px 5px;
+    margin: -5px 0 -5px -5px;
+    flex: 0 0 45px;
+    background-color: #ddd;
+}
+.calendar-event-timesep {
+    line-height: 1.2;
+}
+.calendar-event-timesep:before {
+    display: block;
+    content: "⋮";
+}
+.calendar-event-description {
+    flex-grow: 100;
+    margin: 0 5px;
+    word-break: break-word;
+    word-wrap: break-word;
+    hyphens: auto;
+}
+.calendar-event-description, .calendar-event-time {
+    display: flex;
+    flex-direction: column;
+    justify-content: center;
+}
+.calendar-event-type {
+    flex: 0 0 12px;
+    margin: -5px -5px -5px 0;
+}
+
+@media only screen and (max-width: 960px) {
+    .calendar-event {
+        flex-direction: column;
+    }
+    .calendar-event-time {
+        flex-direction: row;
+        padding: 5px 8px 5px 5px;
+        margin: -5px -5px 5px -5px;
+        flex: 0 0 12px;
+        align-content: center;
+        justify-content: center;
+    }
+    .calendar-event-type {
+        flex: 0 0 12px;
+        margin: 5px -5px -5px -5px;
+    }
+    .calendar-event-timesep {
+        display: block;
+    }
+    .calendar-event-timesep:before {
+        display: block;
+        content: "...";
+        padding: 0 3px;
+    }
+}
+
+.calendar-date-date, .calendar-event {
+    /* make sure border radius clips content */
+    overflow: hidden;
+}
+
+details.calendar-event-details > summary {
+    text-decoration: underline dotted black;
+}
+.calendar-popover-content > * {
+    margin: 5px 0;
+}
+
+.calendar-popover-entry {
+    display: flex;
+    margin: 5px 0;
+}
+.calendar-popover-entry-icon {
+    flex: 0 0 18px;
+}
+
+/* CSS-only "fake soft open", might be replaced something more sophisticated in the future */
+details.calendar-event-details[open] summary ~ * {
+  animation: calendar-event-details-sweep .5s ease-in-out;
+}
+@keyframes calendar-event-details-sweep {
+  0%    {opacity: 0; transform: translateY(-10px)}
+  100%  {opacity: 1; transform: translateY(0)}
+}

templates/embed-sidebar.html

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+<!DOCTYPE html>
+<html lang="de">
+    <head>
+        {#- TODO: replace with locally served files #}
+        <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/normalize/8.0.1/normalize.css">
+        <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/milligram/1.4.1/milligram.css">
+        <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.1.1/css/all.min.css">
+
+        <link rel="stylesheet" href="{{ url_for('static', path='style.css') }}" type="text/css"/>
+        <link rel="stylesheet" href="{{ url_for('static', path='roboto.css') }}" type="text/css"/>
+        <title>Embeddable calendar</title>
+    </head>
+
+    <body{% if max_width %} style="max-width: {{ max_width }}"{% endif %}>
+        <div class="calendar">
+            {% for start_date, events in grouped_events[:3] %}
+            <div class="calendar-date">
+                <div class="calendar-date-date">
+                    <div class="calendar-date-month">
+                        {{ start_date.strftime("%b") }}
+                    </div>
+                    <div class="calendar-date-day">
+                        {{ start_date.strftime("%d") }}
+                    </div>
+                    <div class="calendar-date-weekday">
+                        {{ start_date.strftime("%a") }}
+                    </div>
+                </div>
+                <div class="calendar-events">
+                    {% for event in events %}
+                    <div class="calendar-event" title="{{ event.summary }}{% if event.description %} &mdash; {{ event.description }}{% endif %}">
+                        <div class="calendar-event-time">
+                            <div class="calendar-event-starttime">{{ event.start.strftime("%H:%M") }}</div>
+                            <div class="calendar-event-timesep"></div>
+                            <div class="calendar-event-endtime">{{ event.end.strftime("%H:%M") }}</div>
+                        </div>
+                        <div class="calendar-event-description">
+                            {% if event.description or event.location %}
+                            <details class="calendar-event-details">
+                                <summary>{{ event.summary }}</summary>
+                                <div class="calendar-popover-content">
+                                    {% if event.description %}
+                                    <div class="calendar-popover-entry">
+                                        {#- description doesn't need an icon, just wastes space #}
+                                        <div class="calendar-popover-entry-text">{{ event.description }}</div>
+                                    </div>
+                                    {% endif %}
+                                    {% if event.location %}
+                                    <div class="calendar-popover-entry">
+                                        <div class="calendar-popover-entry-icon"><i class="fa-solid fa-location-dot"></i></div>
+                                        <div class="calendar-popover-entry-text">{{ event.location }}</div>
+                                    </div>
+                                    {% endif %}
+                                </div>
+                            </details>
+                            {% else %}
+                            <span>{{ event.summary }}</span>
+                            {% endif %}
+                        </div>
+                        <div class="calendar-event-type" style="background-color: {{ event.color }};"></div>
+                    </div>
+                    {% endfor %}
+                </div>
+            </div>
+            {% endfor %}
+        </div>
+    </body>
+</html>