Allow nodes to have edges that reference themselves

[ashleyconnor]

I'm looking at using diagrams to produce network diagrams for AWS Security Groups and one of the requirements is that a Security Group can reference itself to allow inbound and outbound traffic on a certain port.

I'm looking a producing a node that can have edges that look something like this.

[clayms]

You just need to change the graph_attr dictionary key "splines" to the value "spline" (default in this library is "ortho").

Then specify the headport and tailport of the self-referring Edges.

from diagrams import Diagram, Node, Edge

graph_attr = {
    "splines": "spline",
}

with Diagram('',show=False, graph_attr=graph_attr) as diag:
    idle = Node('Idle', shape="doublecircle", labelloc="c",)
    working = Node('Working', shape="circle", labelloc="c",)

    idle >> Edge(label="boot",) >> working

    working >> Edge(label="sendtx[i]", tailport="n", headport="n") >> working
    working >> Edge(label="qry", tailport="e", headport="e") >> working
    working >> Edge(label="response[j]", tailport="s", headport="s") >> working

diag

Ref:
https://graphviz.gitlab.io/doc/info/attrs.html#d:headport
https://graphviz.gitlab.io/doc/info/attrs.html#d:tailport
https://graphviz.gitlab.io/doc/info/attrs.html#k:portPos

[ashleyconnor]

This worked!

Thank you for the quick answer and contributing to such an awesome project.