Importer Interface/Abstract class

[KrzysztofMadejski]

So it standardizes importers from various external sources: FTP, HTTP, S3

Features / acceptance criteria

• Refactor interfaces
  • drop pyutil lib
  • interfaces defined as ABC classes
• Be able to configure importers in settings
  • list active
  • provide default params to enabled ones
  • be able to specify a few importers of the same type, but different data sources
• One interface/abstract class standardizing communication
• Clear way to create tasks based on the document
  • maybe an interface for tasks iCreateOnDocument that would automatically be called as createOnDocument(document) and tasks would implement it
  • now there is no customization possible, but basic case is covered: listing tasks that should be created in model annotation

    @document(on_import_create=['opora.tasks.FindTableTask'])
    class Report(models.Model):
    

• Ability to register some view in the admin panel that would allow admin to import external documents:
  • specifying source
  • optionally choosing from a list / navigating a file tree (this could be a standard component - I've started developing it for PyBossa)
  • (optionally) choosing which tasks should be created
• Classes implementing this interface should be auto-registered in Moonsheep
• Run options: asking for input in the process (such as choosing documents)
  • from command line Import documents from HTTP server listings [backend + console] #136
  • from web web interface Import documents from HTTP / FTP / S3 UI #88