Directed Acyclic Graph

Dagraph provides DAG functionality to ActiveRecord models

Installation

Gemfile

gem 'dagraph', github: 'nmix/dagraph'

Install gem

bundle install

Generate migration and run migrate

bin/rails generate dagraph:migration
bin/rake db:migrate

Add acs_as_dagraph to model

class Unit < ActiveRecord::Base
	acts_as_dagraph
end

Usage

Creation

# create units
unit7 = Unit.create(code: "7")
unit5 = Unit.create(code: "5")
unit3 = ...
# create graph with weights
unit7.add_child(unit11, 4)
unit7.add_child(unit8, 1)
unit5.add_child(unit11, 6)
unit3.add_child(unit8, 5)
unit3.add_child(unit10, 7)

unit2.add_parent(unit11, 9)
unit9.add_parent(unit11, 2)
unit9.add_parent(unit8, 1)
unit10.add_parent(unit11, 1)

Children and parents

Get all children (direct descendants)

unit7.children
# => [#<Unit id: 4, code: "11">, #<Unit id: 5, code: "8">]

Get all parents (direct ancestors)

unit8.parents
# => [#<Unit id: 1, code: "7">, #<Unit id: 3, code: "3">]

Routing

Get all of the routes passing through the node ({route_id => [nodes], ...)

unit11.routing
# => {1=>[#<Unit id: 1, code: "7">, #<Unit id: 4, code: "11">, #<Unit id: 7, code: "9">], 3=>[#<Unit id: 1, code: "7">, #<Unit id: 4, code: "11">, #<Unit id: 8, code: "10">], 4=>[#<Unit id: 2, code: "5">, #<Unit id: 4, code: "11">, #<Unit id: 7, code: "9">], 5=>[#<Unit id: 2, code: "5">, #<Unit id: 4, code: "11">, #<Unit id: 8, code: "10">], 6=>[#<Unit id: 1, code: "7">, #<Unit id: 4, code: "11">, #<Unit id: 6, code: "2">], 7=>[#<Unit id: 2, code: "5">, #<Unit id: 4, code: "11">, #<Unit id: 6, code: "2">]}

unit10.routing
# => {3=>[#<Unit id: 1, code: "7">, #<Unit id: 4, code: "11">, #<Unit id: 8, code: "10">], 5=>[#<Unit id: 2, code: "5">, #<Unit id: 4, code: "11">, #<Unit id: 8, code: "10">], 9=>[#<Unit id: 3, code: "3">, #<Unit id: 8, code: "10">]}

Descendants and ancestors

Get all descendants (split to routes)

unit5.descendats
# => [[#<Unit id: 4, code: "11">, #<Unit id: 7, code: "9">], [#<Unit id: 4, code: "11">, #<Unit id: 8, code: "10">], [#<Unit id: 4, code: "11">, #<Unit id: 6, code: "2">]]

Get all uniq descendants (without routes)

unit5.descendats.flatten.uniq
# => [#<Unit id: 4, code: "11">, #<Unit id: 7, code: "9">, #<Unit id: 8, code: "10">, #<Unit id: 6, code: "2">]

Get all ancestors (split to routes)

unit10.ancestors
# => [[#<Unit id: 1, code: "7">, #<Unit id: 4, code: "11">], [#<Unit id: 2, code: "5">, #<Unit id: 4, code: "11">], [#<Unit id: 3, code: "3">]]

Get all uniq ancestors (without routes)

unit10.ancestors.flatten.uniq
# => [#<Unit id: 1, code: "7">, #<Unit id: 4, code: "11">, #<Unit id: 2, code: "5">, #<Unit id: 3, code: "3">]

Weights

Get children with weights

unit3.children_weights
# => [[#<Unit id: 5, code: "8">, 5], [#<Unit id: 8, code: "10">, 7]]

Parents with weights

unit10.parents_weights
# [[#<Unit id: 4, code: "11">, 1], [#<Unit id: 3, code: "3">, 7]]

Get all ancestors with weights (split by routes)

unit9.ancestors_weights (split by routes)
=> [[[#<Unit id: 1, code: "7">, 4], [#<Unit id: 4, code: "11">, 2]], [[#<Unit id: 1, code: "7">, 1], [#<Unit id: 5, code: "8">, 1]], [[#<Unit id: 2, code: "5">, 6], [#<Unit id: 4, code: "11">, 2]], [[#<Unit id: 3, code: "3">, 5], [#<Unit id: 5, code: "8">, 1]]]

Get all descendants with weights (split by routes)

uniq5.descendats_weights
# => [[[#<Unit id: 4, code: "11">, 6], [#<Unit id: 7, code: "9">, 2]], [[#<Unit id: 4, code: "11">, 6], [#<Unit id: 8, code: "10">, 1]], [[#<Unit id: 4, code: "11">, 6], [#<Unit id: 6, code: "2">, 9]]]

Get all descendants with comprised weights (assembly-like-weight-calculation)

unit7.descendants_assembled
# => [[#<Unit id: 4, code: "11">, 4], [#<Unit id: 7, code: "9">, 9], [#<Unit id: 5, code: "8">, 1], [#<Unit id: 8, code: "10">, 4], [#<Unit id: 6, code: "2">, 36]]

Errors

Trying to add node to itself

unit3.add_child(unit3)
# => SelfCyclicError: SelfCyclicError

Trying to create a loop

unit2.add_child(unit7)
# => CyclicError: CyclicError
unit3.add_parent(unit9)
# => CyclicError: CyclicError

Trying to duplicate edge

unit7.add_child(unit11)
DuplicationError: DuplicationError
unit10.add_parent(unit3)
DuplicationError: DuplicationError

Destroying

Remove a child

unit11.children
# => [#<Unit id: 7, code: "9">, #<Unit id: 8, code: "10">, #<Unit id: 6, code: "2">]
unit11.remove_child(unit9)
# => [#<Unit id: 8, code: "10">, #<Unit id: 6, code: "2">]

Remove all children

unit11.children
# => [#<Unit id: 8, code: "10">, #<Unit id: 6, code: "2">]
unit11.remove_children
# => []
unit11.children
# => []

Remove a parent

unit8.parents
# => [#<Unit id: 1, code: "7">, #<Unit id: 3, code: "3">]
unit8.remove_parent(unit7)
# => [#<Unit id: 3, code: "3">]

Remove all parents

unit8.remove_parents
=> []

Methods

method	description
`unit.add_child(another_unit)`	Add `another_unit` as a child node to the `unit`
`unit.add_parent(another_unit)`	Set `another_unit` as a parent node for the `unit`
`unit.parents`	Get all parents of the `unit`
`unit.parents_weights`	Get all parents with weights
`unit.children`	Get all children of the `unit`
`unit.children_weights`	Get all children with weights
`unit.routing`	Get hash of all routes passing the `unit`
`unit.ancestors`	Get array of ancestors of the unit (split by routes)
`unit.self_and_ancetors`	Get array of ancestors including self node (split by routes)
`unit.ancestors_weights`	Get array of ancestors with weights (split by routes)
`unit.descendants`	Get array of descendants of the unit (split by routes)
`unit.self_and_descendants`	Get array of descendants including self node (split by routes)
`unit.descendants_weights`	Get array of descendants with weights (split by routes)
`unit.descendants_assembled`	Get array of descendants with comprised weights (assembly-like-weight-calculation)
`unit.roots`	Get array of root units from ancestors
`unit.leafs`	Get array of leaf units from descendants
`unit.root?`	`true` if unit has no parents
`unit.leaf?`	`true` if unit has no children
`unit.isolated?`	`true` if node has no children no parents
`Unit.roots`	Get array of units without children
`Unit.leafs`	Get array of units without parents

License

This project rocks and uses MIT-LICENSE.

Atastor / dagraph