Add mybinder badge

[ian-r-rose]

Adds mybinder and GitHub buttons to the toolbar. The mybinder button is only active if the user is currently viewing a repository that contains one of the special files listed in repo2docker.

Still not working: specifying other branches than master, launching binder with more a more specific subdirectory.
cc. @choldgraf @yuvipanda.

[yuvipanda]

/cc @willingc @Carreau @minrk @betatim too! this is awesome!

[ian-r-rose]

Screengrab:

[willingc]

@ian-r-rose Lovely 👍 Any chance that you can make the icons look more clickable (perhaps that was what the latest style tweak did)? Great job.

[ian-r-rose]

The icons gain a border upon mouse hover (in the same way that buttons in the filebrowser do).

[choldgraf]

this is super cool! thanks @ian-r-rose ! A couple quick thoughts:

1. We should (in a diff issue) have a conversation about what kind of "official" binder buttons we should put out there. E.g., I like @ian-r-rose using the binder logo here...
2. One trick here is that the binder build files are quite common outside of a binder context (e.g. requirements.txt). I'm a little concerned that the plugin will catch these cases where the repo still isn't binderable... what do you all think?

[ian-r-rose]

1. Agreed. For prior work on this, see the Jupyter branding guidelines here. In general, we have said it is fine to use the logo if advertising integration with the project, but not to use it for other purposes. Modifying it is also against the guidelines. (As I have done slightly by removing the binder text!).

2. Yes, that is tricky, and would require much more introspection into the repository. Here, I am only checking if files with those names exist, and it will definitely catch cases where binder will not work. You probably have a better idea of how to improve the screening than I.

[willingc]

2. @ian-r-rose, if I understand correctly the jupyterlab user could choose whether or not to install/disable this feature. If so, then the user can opt out if desired. Perhaps adding to a message on hover that it builds based on current repo contents and YMMV (i.e. user would need to make sure the contents are binderable).

[choldgraf]

That's a good point about people being able to opt out @willingc ... I like the idea of it being enabled by default though, it'll hopefully let some people know about the binder world!

[ian-r-rose]

2. @willingc, it is currently enabled in this plugin. I have been thinking through how to make it more configurable though, including

• whether to make it disabled
• the ability to set a different deployment of binderhub

[ian-r-rose]

(Since this is an extension to JupyterLab, none of it is installed by default in a basic pip install jupyterlab)

[willingc]

Thanks @ian-r-rose. For now, I wouldn't be too concerned about 2 until we can spec out what would specifically be needed.