docs: add Launch-on-REANA badges

[tiborsimko]

Add "Launch-on-REANA" badges to the README file.

We have a lot of reana-*.yaml, so think about a nice presentation.

We can restrict ourselves to only four badges, cwl/serial/snakemake/yadage.

We don't have to cover HTCondor or Slurm.

[tiborsimko]

Possible badge: "Launch helloworld snakemake on REANA @ CERN" but it could be too wide.

Another option would be to simply write things in text: Launch helloworld snakemake example: [Launch | REANA] so that the text is wider and badge nicely shorter.

Anyway, needs some experimenting with Markdown formatting and text placement...

[VMois]

• Without a third-party badge generator, our only option is the "Launch on REANA" badge. In this case, we will need additional text to indicate that this badge will run CWL or Yadage. Example:

Launch helloworld Snakemake example:

• With a third-party badge generator (shields.io, in this example), we can have any text:

I don't think it makes sense to include the demo workflow name (e.g helloworld) in the badge cause users have already opened the repository and saw what they are about to run. Multiple badges example:

[]() []() []()

If we will go with some generic "Launch with Yadage on REANA@CERN" we can also self-host a few badges more, but I am not sure how good this idea.

My preference would be third-party custom text like this:

I will try to add this, see what it looks like, and add screenshots here.

[mvidalgarcia]

Some ideas if we only keep the badge hosted on www.reana.io:

Serial	CWL	Snakemake	Yadage

Serial
CWL
Snakemake
Yadage

I don't think it makes sense to include the demo workflow name (e.g helloworld) in the badge cause users have already opened the repository and saw what they are about to run.

Agreed.

[VMois]

Some ideas if we only keep the badge hosted on www.reana.io:

I like the usage of tables and a default badge. Especially, the first one - the horizontal table.

[VMois]

One thing I am worried about is that we do not have a clear call to action in some demo examples. With 4 badges it might be confusing for a new user to decide what to click on.

Some demo examples have only one workflow type which makes things easier, but, in the case of multiple badges, it would be nice to highlight the default one, for example.

[tiborsimko]

You can experiment changing the README and making a PR to see how things will look in the final product.

E.g. if there is only one badge, it can be placed next to "licence: MIT" badge on top, and it can be teh default one, and everything should be rather clear to users.

However, it may be good to alter the section "Running the example on REANA cloud" occurring down the README file page too, so that people know that they can simply click on a badge as a parallel technique. (See e.g. CMS open data example that shows badges down in the text.)

This may be especially interesting if we have four badges to display, one for each workflow engine. It may be too much to put them all at the top, since novice users haven't managed to even read what the example is about. So "Running..." may be a better place; we also have more textual room down there for better presentations and explanations.

(One could combine both techniques: show one simple default badge at the top, and several workflow-specific badges at the bottom in the "Running..." section.)

WRT CWL/Serial/Snakemake/Yadage badges and texts, we should make it rather clear that only one of them is in principle necessary, whatever each user usually uses should catch the eye. Hence I like the proposed text "Launch with Yadage on | REANA@CERN" which seems nicely engaging and which presents the essential of the what is going on in one concise phrase. (Plus it would be clear where things will run, REANA@CERN, for REANA@NYI, REANA@BNL users. Plus it would "pre-warn" non-CERN users that they might not have appropriate rights to run it there.)

If we go this way, then we can generate a set of four badges and host them on www.reana.io as well, to avoid depending on external services. (Via another PR to www.reana.io.)

[VMois]

Does it makes sense for our self-hosted badge "Launch on REANA" to be changed to "Launch on REANA@CERN"?

I have opened PR for ATLAS where we have only a single specification file. It is an easy decision, we can put it on top. So one question to resolve is whatever we want to add "at CERN" at the end of the badge?