Support configuring multiple organizations centrally

[Simon-Boyer]

Prerequisites:

• Is the functionality available in the GitHub UI? If so, please provide a link to information about the feature.
  Yes, no pertinent link

• Is the functionality available through the GitHub API? If the functionality is available, please provide links to the
  API documentation (https://developer.github.com/v3/) as well as the Octokit documentation (https://octokit.github.io/).
  Yes, no pertinent link

• If the functionality is not yet available in the API, it would be helpful if you
  contacted support (https://support.github.com/) or posted in the Community Forum (https://i.8713187.xyzmunity/). Please
  include a link to the forum post if you create one or a copy of the response from support.

New Feature

Working with enterprise contexts, I think it would be interesting to be able to manage multiple orgs from a single Safe-Settings instance and a single admin repository. It would allow central management of repository in enterprise context, where you may not want to split these configs between orgs.

Although this may seem major, I think it actually may be quite minimal as a code change. I think updating index.js could be sufficient to add this use case. For example we could have the following paths: .github/ORG_NAME/repos/.... Basically keeping the same code but splitting at the base using the ORG_NAME to select the installation id it needs to apply the changes to.

We would need to make sure it doesnt change the flow of the existing org-centric deployments, so maybe with a env var switch or by using a different file structure that does not intersect with the existing one.

I might have time to develop something like that, but I do want your comments / opinions on this before I start writing a PR, this is still a pretty major feature.

@decyjphr for visibility

[Simon-Boyer]

Another idea I had, is to still have multiple instances of safe-settings, but simply play with env vars to allow setting different installation and org for source repo vs target org. Combined with existing CONFIG_PATH var, we could easily set a central repo for different orgs

[decyjphr]

Hi, the best way to do this is using enterprise owned GitHub apps

Otherwise, it becomes tricky to authenticate the app with the GitHub app token for the right installation when a webhook comes.

If we want to take this approach it would work without any code change. And if we want to centralize the settings to a single repo on top of that, we could do that with some custom code, however that repo would have to be internal so that the app can use the installation token from any org to read this repo.