make cluster ranks the same in for loop

[errolsancaktar]

given the code below i'm trying to get each vpc cluster to be on top of each other. typically i would do some penwidth=0 lines to keep everything ordered appropriately but i'm unclear on how to do that when the items were generated using a loop.

graph_attr = {
    "arrowsize": "2",
    "bgcolor": "white",  # transparent
    "overlap": "false",
    "nodesep": "2.0",
    "ranksep": "1.5",
    "layout": "dot",
    "compound": "false",


}

edge_attr = {
    "penwidth": "2.0",
    "pencolor": "gray",
    
}

subnet_attr = {"bgcolor": "lightgreen"}
environments = ["dev", "qa"]
azs = ["us-east-1b"]
online_vms = {}
with Diagram("Shared Services test", show=False, direction="TB", graph_attr={}, edge_attr={},filename="Shared/Diagrams/sharedsvcs") as diag1:

  with Cluster("Example 1"):
    tgw = TransitGateway("Shared Services TGW")
    for env in environments:
      with Cluster(f"{env} VPC"):
        # Looping through Private first and then Public instead of doing it all in one for loop
        # for rendering purposes (so it doesn't go private, public, private, public)
        for az in azs:
          with Cluster(f"{az}\nPrivate Subnet"):
            instance = [
              EC2Instance(f"Web Service"),
              EC2Instance(f"inst2")
            ]
            nic = VPCElasticNetworkInterface("TGW Connectivity")
            # nic << Edge() >> tgw
        for az in azs:
          with Cluster(f"{az}\nPublic Subnet"):
            alb = ALB(f"ALB")
            # alb >> Edge() >> online_vms[env]
            gw = NATGateway(f"NAT Gateway\nInternet Access")

[errolsancaktar]

something like this:

[Anddd7]

You can add some 'hidden points & lines' to reorder the nodes.

• by default, direction="TB" will list your nodes from left2right, because there is no any relations
• then, if you NAT_QA -- NAT_DEV, TB layout will move dev to next line

So, if you have enough patient, you can create additional Node(color=transparent), Edge(color=transparent), Cluster(color=transparent) to order nodes.

e.g. to make 3 clusters vertical, I create 3 hidden points in each of them, and connect with hidden edge.

with Cluster("identity"):
    S3()
    Terraform()
    Cloudtrail()
    p1 = HiddenPoint()
with Cluster("identity2"):
    S3()
    Terraform()
    Cloudtrail()
    p2 = HiddenPoint()
with Cluster("identity3"):
    S3()
    Terraform()
    Cloudtrail()
    p3 = HiddenPoint()

# p1 - p2 - p3
peercluster(p1, p2, p3, penwidth="0", minlen="1")  # util method in my repo

Sample: https://github.com/Anddd7/diagrams-patterns/blob/main/poc_aws_complex.py#L94

---

Another way is using neato as the layout engine, then create node with x,y ... if you really want to control the layout

Sample: https://github.com/Anddd7/diagrams-patterns/blob/main/poc_neato_overlap.py