ConceptsΒΆ

Internally, django-directed uses a combination of factories and abstract models, which makes possible:

  • Composition of graph model sets with limited repetition of code

  • Registering base model types for use with other project and in django-directed-admin

  • Passing a standardized configuration object to the factory to change model functionality

Within a Django project utilizing django-directed the graph, edges, and nodes are represented as distinct concrete models, and multiple types of graphs can be built within the same project. These three work together to provide a consolidated API for working with graphs.

  • a Graph model (extended from BaseGraph and then AbstractGraph)

  • an Edge model (extended from BaseEdge and then AbstractEdge)

  • a Node model (extended from BaseNode and then AbstractNode)

erDiagram Graph { any id } Node { ManyToManyField children } Edge { Graph id PK Node parent FK "parent Node" Node child FK "child Node" } Graph ||--o{ Edge : "" Node ||--o{ Edge : parent Node ||--o{ Edge : child Node }|--|{ Node : "M2M through Edge"

The connected graph is defined by the Edges associated with a Graph instance. This does mean an additional join on the Gaph table, but for typical use-cases the ratio of Graph instances to those of Nodes and Edges is tiny.