I am wondering how to properly draw a supervision tree: I have earlier worked with UML diagrams, and I have used multiple computer tools in the past ( nomnoml, draw.io, and paid solutions like gliffy ), after sketching on paper by hand.
My question: Is there a good (maybe standardized?) way to draw supervision trees? Especially I am wondering how to indicate that something starts multiple processes, what processes communicate (even though they might not be siblings in the supervision-structure) and how to indicate the different supervision strategies that are used?
Also, are there any tools that are really good at making these kind of diagrams?
If you are more the “I like my fancy graphics generated from stupid ASCII-sourcefiles”-guy, there is a tool available called mscgen, which can produce graphics similar to the second image shown above.
Also there is currently no standardized way I am aware of to actually draw a supervision tree (or process tree in generall) for erlang or any other language. The way I do see it at most is a very simple view of just plain nodes and vertices. I haven’t seen any distictions so far between process “types” (Supervisor, GenServer or whatever we have in erlang and Elixir available).
For a documentation I am currently writing (erlang software) I do follow a very simple scheme so far.
Important for this documentation is only the distinction between application, supervisor, gen_server, and gen_fsm, everything else is just a process and remains a “plain” node. The other 4 are just annotated with an overlayed square icon in the upper right corner of the node, where the icon is in fact only a single letter: “A” for application, “V” for supervisor, “S” for gen_server and “F” for gen_fsm.
If someone does find a standard way to draw them I would be very glad to use it in my documentation
One of the images i really liked, is from the the Zen of Erlang article:
This looks like it was also made with some kind of tool (rather than being human-drawn). I really like how it shows that something might have more siblings, and that something has multiple of a kind below it. It also designates supervisors as rounded rectangles while workers are circles.
