JSON-Daten ins Webformular einpflegen

I have a JSON file that needs to be read and its values written into a web form that contains well over ten separate text fields. The form has no checkboxes or dropdowns, so the task focuses purely on populating text inputs. A handful of those fields come with their own validation rules—length restrictions, date formatting, or specific character sets—and the solution has to respect these checks before the form can be submitted.

My ideal workflow is a small, easily adaptable script (Python + Selenium, JavaScript + Puppeteer, or any equivalent you prefer) that:
• loads the JSON,
• maps each key to the correct input element,
• applies or mimics the existing in-page validation where required, and
• submits the form (or shows clear errors) once all data pass the rules.

Please keep the script readable and add brief comments so I can adjust mappings later if field names change. I will provide a sample JSON file and a staging URL once we start. If anything is unclear about the validation logic, feel free to flag it early so we can refine the requirements together.