synapzee/ics-filter repository overview

⁠ICS Filter

This application serves as a relay between an ics provider (through HTTP) and an application, it remove blacklisted elements from the calendar before sending it back.

Currently, it's hard configured to cache for 60 seconds a fetch from source ics for performance reason and to prevent source of DDoS.

⁠Environment variable

• Mandatory SOURCE_ICS: HTTP/HTTPS url to your ics provider (e.g. https://chronosvenger.me/?classe=GISTRE.ics⁠)
• Mandatory ICS_BLACKLIST_FILE: Path where the blacklist file will be read or saved.

⁠How to launch a test server ?

You can test it by invoking ics_filter/ics_filter.py serve which will deploy an http.server bind to 0.0.0.0:8000 (hardcoded values).

Warning: This must not be used in production.

⁠How to use in production ?

You can get an wsgi application with create_app() function or the module variable wsgi, the easiest way to use production WSGI server such as for example Waitress⁠ or Gunicorn⁠.

Examples:

gunicorn \
      --env 'SOURCE_ICS=https://chronosvenger.me/?classe=GISTRE.ics' \
      --env 'ICS_BLACKLIST_FILE=.calendar-blacklist' \
      --access-logfile - -b 0.0.0.0:8000 'ics_filter:wsgi'

⁠Docker

https://hub.docker.com/r/synapzee/ics-filter⁠

By default, the blacklist file will be stored at /opt/ics_filter/ics-events-blacklist.

Example on how to use:

Create in your host /opt/ics_filter which will be used to make the blacklist persistent. To start ics-filter, will be served inside with Gunicorn and exposed by the port 8000:

docker run -d --name ics-filter \
    -v /opt/ics_filter:/opt/ics_filter \
    -p 8000:8000 \
    -e SOURCE_ICS='<your_ics_source>' \
    synapzee/ics-filter

Note: Please avoid binding it to 0.0.0.0, but prefer something like -p 127.0.0.1:8000:8000.

Add or remove events in blacklist:

docker run -it \
    -v /opt/ics_filter:/opt/ics_filter \
    -e 'SOURCE_ICS=<your_ics_source>' \
    synapzee/ics-filter \
    ics-filter manage-blacklist

Note: You must restart your docker instance for changes to take effects.