This is a small site that allows you to generate a JSON output compatible with JSON Résumé (version 0.0.0) from your LinkedIn profile.
Try the demo on http://jmperezperez.com/linkedin-to-json-resume/
The project uses the Sign with LinkedIn button together with LinkedIn's API to fetch a user's profile on LinkedIn and convert it to the format expected by JSON Résumé.
Note that due to some limitations in LinkedIn's API, not all the data exposed on LinkedIn's site is available through their API. For example, start and end dates for volunteer, or honors & awards.