api: serve updated parameters in spec endpoint

[mvidalgarcia]

The spec endpoint returns the original REANA specification but doesn't update its parameters when those are set via reana-client.

Steps to reproduce:

1. Run (reana-demo-root6-roofit)

 reana-client run -w roofit -p events=1000

2. Go to UI, workflow details page, Specification tab and check parameters.

Can be addressed at the same time as #227 if possible.

[mvidalgarcia]

As discussed during the standup we decided to keep Workflow.reana_specification as the source of truth and never modify it. Aggregations/overwritings as operational input parameters must be handled per operation basis, as done in the diff operation.

Now the problem arises on how to display this information in the UI. Some ideas that come to my head:

• a) Create a new tab for input parameters. (Perhaps overkill and mostly empty).
• b) Display a small box in the specification tab on top of the specification itself with the passed parameters. Return operational params in the same endpoint.
• c) Display specification using diff format, so user is aware of original and new value.

@reanahub/developers WDYT? 💭

[diegodelemos]

I agree option a) would be an overkill if it only contains inputs.parameters , however, what if it contains all inputs (reana.yaml speaking it would be parameters and files)? For instance, the alice lego train has many input files see here.

Option b) seems to align with what Travis does, note that the different sections can be expanded and collapsed:

Regarding option c) I think we should leave diff views to the diff feature itself (when one could, for instance, select two workflow runs and perform a diff action) otherwise I believe it would be confusing. We could use a visual aid instead, for example, gently highlighting the line and a tooltip to explain the situation (of course better than this 😅):

For me option c) with a different look than diff is the more informative and compact of the three.

P.S. It would be worth moving this discussion to an issue in REANA-UI.

[mvidalgarcia]

I agree that your proposal would be the ideal solution. However, at the moment, our CodeSnippet is very limited (that's why I created this issue to evaluate more powerful options) and adding a tooltip would be too much work and it would involve super tricky and dangerours string comparisons. So IMO we should go for option b), at least for the moment.