ARCHITECTURE

ARCHITECTURE

Support For Associations

• only simple associations so far
• polymorphism, and other tricks are as of yet untested
• belongs_to
  • through belongs_to you can hopefully code anything you need to
• has_one, has_many are next

DeepImport.import { ... load logic ... }

• GIST
• signals magic
  • focus on creating all the models and associations
  • everything created in the block will be commited to the database
  • forget calling save, and create_* methods
• DeepImport logic only executes within these blocks
  • this ensures that on any error, deep_import will be a part of relevant stack traces

config/deep_import.yml

• A Hash of 'ModelName' => Hash of Associations
• GIST
  • Association:
    • only 'belongs_to' currently supported
    • an Array of 'ModelName' this model belongs to

Active Record Associations:

• ActiveRecord API
• has_one
  • planned, unsupported
• has_many
  • planned, unsupported
• belongs_to
  • API for Child belongs_to Parent
  • child.parent=
  • child.build_parent
  • child.create_parent
  • child.create_parent!

deep import models

• models and associations are only established once id values are saved to the database
• DeepImport tracks these relationships in ActiveRecord like index models
• for each Model in config file
  • there is a generated DeepImportModel
  • for each belongs_to association
    • there is a deep_import_models.deep_import_belongs_to_id field
• these DeepImport models are responsible for tracking association links
  • before and after serialization or commit to the database

commit algorithm

• for each model class in the import cache
  • DeepImport runs the activerecord-import method
  • for each belongs_to relation
    • DeepImport joins the ModelClass
      • to DeepImportModelClass on a deep_import_id
      • and links to the BelongsToClass using:
        • DeepImportModelClass.deep_import_belongs_to_class_id = BelongsToClass.deep_import_id
• then all DeepImport models are deleted
  • ensuring that no additional space is consumed once initial import is completed