DependencyGraph

A directed acyclic graph of objects and their dependencies.

Attributes

Attribute	Type	Description
formatter	[GraphFormatter](graphformatter.md?sid=celery_utils_graph_graphformatter) = GraphFormatter()	A GraphFormatter instance used to customize the visual representation and labeling of nodes and edges when exporting to DOT format.
adjacent	dict = {}	A dictionary mapping each object to a list of its direct dependencies, representing the adjacency list of the directed graph.

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Constructor

Signature

def DependencyGraph(
    it: iterator = null,
    formatter: [GraphFormatter](graphformatter.md?sid=celery_utils_graph_graphformatter) = null
) - > null

Parameters

Name	Type	Description
it	iterator = null	An optional iterator of (obj, dependencies) tuples to build the graph from.
formatter	[GraphFormatter](graphformatter.md?sid=celery_utils_graph_graphformatter) = null	An optional custom graph formatter; defaults to a new GraphFormatter instance if not provided.

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Methods

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add_arc()

@classmethod
def add_arc(
    obj: Any
)

Add an object to the graph.

Parameters

Name	Type	Description
obj	Any	The object to be added as a node in the graph.

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add_edge()

@classmethod
def add_edge(
    A: Any,
    B: Any
)

Add an edge from object A to object B.

Parameters

Name	Type	Description
A	Any	The source object that depends on another object.
B	Any	The target object that is a dependency of the source.

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connect()

@classmethod
def connect(
    graph: [DependencyGraph](dependencygraph.md?sid=celery_utils_graph_dependencygraph)
)

Add nodes from another graph.

Parameters

Name	Type	Description
graph	[DependencyGraph](dependencygraph.md?sid=celery_utils_graph_dependencygraph)	Another DependencyGraph instance whose adjacency data will be merged into this graph.

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topsort()

@classmethod
def topsort() - > List

Sort the graph topologically.

Returns

Type	Description
List	List: of objects in the order in which they must be handled.

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valency_of()

@classmethod
def valency_of(
    obj: Any
) - > int

Return the valency (degree) of a vertex in the graph.

Parameters

Name	Type	Description
obj	Any	The vertex object whose valency is to be calculated.

Returns

Type	Description
int	The total count of recursive dependencies for the specified object.

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update()

@classmethod
def update(
    it: Iterable
)

Update graph with data from a list of (obj, deps) tuples.

Parameters

Name	Type	Description
it	Iterable	An iterator of tuples where each tuple contains an object and a list of its dependencies.

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edges()

@classmethod
def edges() - > Generator

Return generator that yields for all edges in the graph.

Returns

Type	Description
Generator	A generator yielding objects that have at least one outgoing edge (dependency).

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to_dot()

@classmethod
def to_dot(
    fh: IO,
    formatter: [GraphFormatter](graphformatter.md?sid=celery_utils_graph_graphformatter)
)

Convert the graph to DOT format.

Parameters

Name	Type	Description
fh	IO	A file, or a file-like object to write the graph to.
formatter	[GraphFormatter](graphformatter.md?sid=celery_utils_graph_graphformatter)	Custom graph formatter to use.

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format()

@classmethod
def format(
    obj: Any
) - > Any

Formats a node object using the configured graph formatter.

Parameters

Name	Type	Description
obj	Any	The node object to be formatted.

Returns

Type	Description
Any	The formatted representation of the object, or the object itself if no formatter is set.

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repr_node()

@classmethod
def repr_node(
    obj: Any,
    level: int,
    fmt: str
) - > str

Generates a formatted string representation of a node and its recursive dependencies.

Parameters

Name	Type	Description
obj	Any	The node object to represent.
level	int	The current indentation level for nested dependencies.
fmt	str	A format string used to display the node and its valency.

Returns

Type	Description
str	A multi-line string representing the node's branch in the dependency graph.

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