auto_source: add Scraper for JSON responses (limited to GET requests)

[gildesmarais]

• handle scenario when the response is a jsonfeed.
• When scraping a non-jsonfeed JSON, the non-semantic HTML extractor can use some commonly used [class] names:
  • [ ] card,
  • [ ] headline, title,
  • [ ] link, url, permalink, href, path
  • [ ] hero, teaser, description, excerpt, summary, abstract,
  • [ ] categories, tags, type
  • [ ] date, published_at, created_at => /.*_at$/

Example sites:

1. https://indieappsales.com/indieappsales/banner/app-list.json

[hlascelles]

Another example: https://www.iwm.org.uk/visits/iwm-london/whats-on?field_event_type=Exhibitions

Calls a link inside like this.