QR Code Generator mit Cevi Logo

Dies ist eine einfache API mit Webinterface, das es erlaubt, QR-Codes mit dem Cevi-Logo zu erstellen. QR Codes können als PNG oder SVG erstellt werden und sind in den Farben des Cevi-Logo eingefärbt.

Beispiel eines Cevi-QR-Codes

Die API erstellt QR-Code, die wie folgt aussehen:

How to use?

You can start the backend container with the following command:

docker-compose up --build

Now you can interact with the webinterface on localhost:80. Or you can directly query the API with the following command:

curl --header "Content-Type: application/json"   --request POST   --data '{"link":"https://cevi.ch"}'   http://localhost:5000/svg > qr_code.svg

Available Endpoints

Currently, the following endpoints are available:

• /svg: Generates a QR Code and returns it as a string forming an SVG
• /png: Generates a QR Code and returns it as a byte stream
• /pdf: Generates an A4 PDF with the QR Code, optional title, optional subtitle, and the URL below
• /shorten: Shortens a URL with the Cevi.Tools URL shortener (see below)

All endpoints are queried using a POST request. /svg, /png, and /pdf take a JSON body containing the qr code parameters:

{

  // always required
  "text": "https://link/to/your/url",

  // optional title and subtitle for the A4 PDF printout (used by /pdf)
  "title": "Optionaler Titel",
  "subtitle": "Optionaler Untertitel",

  // optional flag to show the URL below the QR code (used by /pdf, default: true)
  "show_url": true,

  // optional parameters for the QR code
  "options": {
    "color-scheme": "cevi"  // default is "cevi", other options are "black" and "white"
  }

}

Optional URL Shortening

The link form offers a Link kürzen button that swaps the entered URL for a short go.cevi.tools link before the QR code is generated. Shorter content means a less dense QR code, which is easier to scan in print.

The frontend does not talk to the shortener directly. It posts to the backend, which forwards the request to the Cevi.Tools URL shortener with an API key that stays on the server:

curl --header "Content-Type: application/json" \
  --request POST --data '{"text":"https://cevi.ch/a/very/long/path"}' \
  http://localhost:5080/shorten
# {"link": "https://go.cevi.tools/AbC123"}

An optional slug picks the path of the short link instead of a random one. The form offers it as Eigener Kurzname. It may contain letters, digits, dashes and underscores (64 characters at most), and the request fails if the slug is already taken:

curl --header "Content-Type: application/json" \
  --request POST --data '{"text":"https://cevi.ch/a/very/long/path","slug":"sommerlager-2027"}' \
  http://localhost:5080/shorten
# {"link": "https://go.cevi.tools/sommerlager-2027"}

The backend reads the following environment variables:

Variable	Default	Description
SHORTENER_API_KEY	(empty)	Kutt API key. Required — without it /shorten answers 503.
SHORTENER_API_URL	https://backend-go.cevi.tools/api/v2/links	Kutt endpoint to post to.
SHORTENER_DOMAIN	go.cevi.tools	Domain the short links are created on.
SHORTENER_TIMEOUT	10	Request timeout in seconds.

Set the key before starting the stack:

SHORTENER_API_KEY=<your kutt api key> docker-compose up --build

If no key is configured the rest of the generator keeps working; only the shortening button reports that the service is unavailable.