Usage:

1. Fork this repository
2. Enable GitHub Pages with workflow as source.
3. Store the environment variables BASE_URL, ELEMENT_ID, OVERRIDE_SUMMARIES, COOKIE and TENANT_ID in the repos secrets
4. Adjust cronjob in ./.github/workflows/GeneratePage.yml to your needs.
5. Adjust step Run PowerShell Script and Capture Output if you don't want to append to a previous ICS or override course names

Overview

This repository contains a GitHub Actions workflow and a PowerShell script to generate an ICS calendar file from a WebUntis timetable. The workflow is scheduled to run at specific intervals and can also be triggered manually. The PowerShell script fetches data from a specified URL and generates the ICS file for subscription.

PowerShell Script: timeTableToIcs.ps1

timeTableToIcs.ps1 generates ICS file(s) from a WebUntis timetable. The script needs headers and cookies that can be exported from the Chrome Dev Console.

Parameters

• baseUrl: The base URL for the HTTP requests.
• elementType: The return type of the request (default is 1, I don't know what other values might return from the API).
• elementId: The ID of the classes timetable. (Get from URL or Chrome Dev tools)
• date: An array of dates (either as strings or DateTime objects) for which to retrieve timetable data. The default is the current week and the next three weeks.
• OutputFilePath: The output file path for the ICS file (default is calendar.ics).
• dontCreateMultiDayEvents: If set, generating "summary" multi-day events will be skipped.
• overrideSummaries: A hashtable to override the summaries of the courses. The key is the original course (short)name, the value is the new course name.
• appendToPreviousICSat: The path to an existing ICS file to which the new timetable data should be appended.
• splitByCourse: If set, the timetable data will be split into separate ICS files for each course.
• splitByOverrides: If set, the timetable data will be split into separate ICS files for each course defined in overrideSummaries and the remaining misc. classes.
• outAllFormats: If set, the timetable data will be output in all formats.
• cookie: The cookie value for authentication.
• tenantId: The tenant ID for authentication.

Workflow: GeneratePage.yml

The GitHub Actions workflow GeneratePage.yml is designed to update and deploy the ICS calendar file to GitHub Pages. Configure the following secrets in your repository according to the parameters:

• BASE_URL: #####.webuntis.com (Your officially given WebUntis website)
• COOKIE: ################## (Get by opening official page with dev tools and copy)
• ELEMENT_ID: #### (Course ID, 4 digits long, get from URL via official website)
• OVERRIDE_SUMMARIES: @{"GK" = "GK, Gemeinschaftskunde";"LBTL1" = "EL, Elektrotechnik";...}
• TENANT_ID: ####### (Get by opening official page with dev tools and copy http request as PowerShell)

The workflow performs the following steps:

1. Download Previous ICS: Downloads the previous ICS artifact if available.
2. Run PowerShell Script: Executes the PowerShell script to generate a new ICS file.
3. Compare ICS Files: Compares the newly generated ICS file with the previous one.
4. Upload ICS Artifact: Uploads the newly generated ICS file(s) as an artifact.
5. Setup Pages: Configures GitHub Pages for deployment.
6. Upload Artifact: Uploads the artifacts as a Pages artifact.
7. Deploy to GitHub Pages: Deploys the uploaded artifacts to GitHub Pages.

Schedule

The workflow is scheduled to run at the following times:

• Every 6 hours
• Daily at 6:00 UTC
• Daily at 7:00 UTC

..and can also be triggered manually.

Sample launch.json

(for debugging via vscode)

{
    // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "name": "PowerShell: Launch Current File",
            "type": "PowerShell",
            "request": "launch",
            "script": "./timeTableToIcs.ps1",
            "args": [
                //"-Verbose",
                //"-Debug",
                //"-ErrorAction", "Inquire",
                "-baseUrl",         "######.webuntis.com",
                "-elementType",     "1",
                "-elementId",       "####", // Course ID, 4 digits long, get from URL via official website
                "-OutputFilePath",  "calendar.ics",
                "-cookie",          "##################", // Get by opening official page with dev tools and copy http request as PowerShell
                "-tenantId",        "#######", // Get by opening official page with dev tools and copy http request as PowerShell
                "-overrideSummaries", "@{\"GK\" = \"GK, Gemeinschaftskunde\";\"LBTL1\" = \"EL, Elektrotechnik\";\"Wi\" = \"Wi, Wirtschafts- und Sozialkunde\";\"E\" = \"EN, Englisch\";\"D\" = \"DE, Deutsch\";\"LBT1\" = \"BWL, Betriebswirtschaftslehre (LBT1/4)\";\"LBT5\" = \"NT, Netzwerktechnik (LBT5)\";\"LBT4\" = \"BWL/ITSY, BWL/ITSY (LBT4/3/1)\";\"LBT2\" = \"SAE, System- und Anwendungsentwicklung (LBT2)\";\"LBT3\" = \"IST, Informations- und Systemtechnik (LBT3)\"}",
                "-appendToPreviousICSat", "./calendar.ics",
                "-outAllFormats",
                "-splitByOverrides"
            ]
        }
    ]
}