Support multiple forjj plugins repositories by default

Created by: clarsonneur

Introduction

Today, forjj load plugins definition from forjj-contribs

But this means a lot of restriction on this repository in term of development process, build automation and versionning.

A better approach would be to support multiple plugins repositories so that any plugins can have their own lifecycle. Following the forj-oss/forjj-contribs#113, forjj could change his behavior as:

By default:

• when an application name is given, like 'github', forjj will check if a forjj-github repository exist in github. ie https://github.com/forj-oss/forjj-<plugin>/raw/master/<plugin>.yaml
• if not found, forjj will traditionnaly search in forjj-contribs.

If the application define the repo-path :

Forjj will ignore the default behavior and will search in following order to load the plugin definition file:

1. <repo-path>/forjj-<plugin>/raw/master/<plugin>.yaml,
2. <repo-path>/<plugin>/raw/master/<plugin>.yaml If not found, forjj fails

if the application define the absolute-path

Forjj will ignore the default behavior and will search for the plugin definition file to load it

• <absolute-path>/github.yaml If not found, forjj fails

Global setup

For private forge, we already have the ability to use internal collection of plugins. The user can set the CONTRIBS_REPO or contrib-repo(Forjfile) or --contribs-repo to change the default path https://github.com/forj-oss/forjj-contribs/raw/master to something else. But this one requires a 'cloned' forjj-contribs kind of repository. So lifecycle issue identical.

So, we need to add another setup parameter to change the 1. default behavior path, ie https://github.com/forj-oss/forjj-<plugin>/raw/master/ to something else.

We would need something like plugins-repo-path set by default to https://github.com/forj-oss/forjj-{{ .Name }}/raw/master/

like contribs-repo, we could have :

1. Check for FORJJ_PLUGINS_REPO_PATH env variable
2. Check --plugins-repo-path
3. Check in Forjfile for forjj-settings/plugins-repo-path

When to push this US?

At earliest we can. So, I set it for 1.0.

Why?

• There is a need to create more plugins to enhance forjj. otherwise forjj stay too limited.
• At least, we need to add easily hubot, slack, and vault. Vault is a special case. but lifecycle should the same as any other plugins.
• If we want contributions, it must be more open to run plugins outside forjj stored in another public or private place.
• The code itself is not too complex. So ealisy implementable.

Following this change, current plugins can stay in forjj-contribs, but new one can be created anywhere.