When I run bin/console workflow:dump my_entity without passing output to a graph tool through a pipe, the text output is the same with and without metadata. There are neither description nor color in output, that's why the images have default values.

So it looks like the metadata is not dumped.

I confirm that metadata is not dumped and color is hard-coded: https://github.com/symfony/symfony/blob/76465fc1f740f9432ee7edcb3c16d86e0ccbd93b/src/Symfony/Component/Workflow/Dumper/GraphvizDumper.php

So this issue is a feature request.

Setting color in a PlantUML file is not trivial: http://wiki.plantuml.net/site/state-diagram#skinparam

I see several solutions to add colors or formatting:

• add logic in the dumpers in order to format data for the GraphViz and PlantUML formats, it may be very complicated since there are options for borders, font colors, etc.
• pass data from YAML to the dumps without transformation, in other words: we would need to write configuration for each node in metadata and the content would be added to the dumps, so it requires work when writing the configuration and it's easier to implement in Symfony Workflow component (:crossed_fingers:)

I identified 3 possible solutions for the configuration:

Define every option:

blog_publishing:
    transitions:
        to_review:
            metadata:
                label: Submit for review
                arrow_color: "Blue"
                label_color: "MediumBlue"

Pros:

• Simple to write for users

Cons:

• May require lot of work on the dumper to treat every option (there are literally hundreds of options see Font color, name and size)

Define output format directly

blog_publishing:
    transitions:
        to_review:
            metadata:
                label: Submit for review
                arrow_style: "[#Blue]"
                label_prefix: "<font color=MediumBlue>"

Pros:

• Users can define every option they want and it will be added in output file as is

Cons:

• Will work for only dot or PUML output and break the other format

Define output format specifically for dot or puml

blog_publishing:
    transitions:
        to_review:
            metadata:
                label: Submit for review
                puml_format:
                    arrow_style: "[#Blue]"
                    label_prefix: "<font color=MediumBlue>"

Pros:

• Users can define every option they want and it will be added in output file as is
• Users can define options for dot, PUML or both formats

Cons:

• Users must write configuration two times but I think that users will choose dot or PUML formats instead of styling both outputs

Ping @lyrixx please give your feedback on this new feature. 😉

Hello. Thanks for working on this feature.

As you said, it's complicated.

Initially, metadata were not introduced to control the dump redering. But it could be a nice idea to leverage this extension point.

As you have many (2 for now) dumper, it's IMHO a bad idea to support your first option "Define every option" and it's the same for the second option "Define output format directly".

About the third option, I'm not super fan of it too.

So I would like to introduce a new option:

1. We support only a very few range of option (label, arrow_color, label_color)
2. We implement theses options for all dumpers
3. If people want more control on the dumper : They extend a dumper a do what ever they want

What do you think ? Do you want do give it a try ?

Thanks for the detailed answer.

Sorry for the late answer, I think that I'll implement this feature in a bundle so I'll be able to add colors to my project's workflow. Because even if a PR is merged in symfony in a near future, it will be available only on the 4.3 branch and it won't be usable in my project.

I implemented styling in a proof of concept Bundle: https://github.com/alexislefebvre/SymfonyWorkflowStyleBundle

Ok, thanks for your work. If you want to contribute your feature for Symfony, I will be glad to merge it.
For now, I think we can close this issue. But feel free to re-open it if you think it's needed.

Thanks @lyrixx, I'll try to stabilize the feature and I'll open a request for Symfony when it will be working.