Edit step YAML by clicking on the graph

[fishnux]

The other day I felt it would be nice to click on a step on the graph and allow editing of that step's YAML code (not the whole file)

The same could also be said to apply dependencies, like right-click on a step, click the button "Depends on" (on the context menu that should appear) and select the other step to depend on, and such depends_on would be written to the step's YAML :)

Technically speaking, to edit the step's YAML, we would track the array position of that specific step, and when we submit the form to save the new code it would replace in that array position and re-encode the YAML. The case of someone deciding to write multiple steps in that block of code I haven't thought of yet

[yohamta]

@fishnux Thanks for the suggestion! :)
That's a very good idea! Implementing that would make it much easier to define DAGs.

One thing to consider is that updating YAML programmatically might break the user's intended formatting. If there is a library that can update YAML fields while maintaining the original field order, comments, and blank lines, that would be easy to implement. Alternatively, we would have the option of accepting such a drawback when the user updated YAML by clicking the visual graph.

I am wondering if we can use this library for this purpose 🤔
https://github.com/google/yamlfmt

[yohamta]

I think we need to be able to parse and update YAML on the front end (JavaScript) side, not the back end (go). A library like the below might be useful.
https://github.com/eemeli/yaml

[fishnux]

Very interesting insight on preserving comments! I did a quick check on that yamlfmt, don't think it would be useful - the "basic" formatter there uses regular YAML marshal/unmarshal. Here's the relevant discussion for marshalling/unmarshalling with comments which still doesn't have a "solid" solution as far as I understand, although there are some forks with partial functionality or even apparently YAML v3 with support for comments, though probably not as widely documented:
go-yaml/yaml#132
https://stackoverflow.com/questions/56401238/how-to-unmarshall-yaml-v3-with-full-access-to-node

If a proper front-end library is available for that, that could be an option as well 😉

[yohamta]

Thanks for the info, really helpful 🙂
I guess we should probably accept the drawback for now that when an user edit the DAG on the graph, the comments are deleted. I feel that the advantages outweigh the disadvantages.

[fishnux]

Maybe as a temporary workaround we add a comment field to the YAML on each step

[yohamta]

Sounds good! :)