Okay, so, this is continuing off the back of a bunch of other posts, and all that stuff I've been muttering on about in the irc channel.

Currently the plugin architecture in NodeBB is built on top of npm, this has massive benefits for us, but isn't without its drawbacks. A major benefit is that we don't need to setup and maintain some sort of registry and mechanism for publishing plugins (npm is that). However, a drawback is that the discoverability of plugins is fairly low, we don't have any awesome plugins.nodebb.org or anything like that.

I've been doing a little bit of research as to how far you can push (read: abuse) npm for an application-specific registry, without setting up an entirely separate registry. So, far, I've found out the following things:

It's super easy to monitor the official registry to discover newly published packages (see: https://gist.github.com/miksago/35eeafc0f031d2248269)
Using this monitoring, we can filter the changes in the registry by doing matching against the id value, such that we can find just changes to nodebb- prefixed packages.

Once we know when nodebb related packages are changed in npm, we can then do cool things like analyse their plugin metadata and find out all sorts of weird and wonderful things.

There is a caveat with how we'd currently have to implement this for nodebb plugins today: in order to get the plugin metadata, we need to read the plugin.json file. In order to read this file, we'd need to download the packages' tarball, extract it, and grab the contents of the plugin.json file. This means our servers would need to do a tonne more processing work, and we'd need to figure out some method to make this actually maintainable. (i.e., what happens if we fail to fetch the tarball, or we don't find a plugin.json file, or our servers run out of disk space?)

What we could do, as a massively breaking change, is to inline the plugin.json into the package.json file. I've done an example of what this might look like here: https://registry.npmjs.org/nodebb-plugin-test/0.0.2 — I'm using the nodebb key as the location in package.json for nodebb specific information. As for which versions of nodebb a plugin supports, I'm currently using this "versions" field.

I think it may be fair to say that we could put that information into the "engines" hash that package.json supports as a "nodebb": ">0.5.0" style value. You can do that for npm and not just node, which is typically what is in the engines hash. Is nodebb an engine?

Anyway, all of this considered, we'd be able to make a very lightweight front-end / index of nodebb plugins that's super up-to-date with npm by use of replication / the changes feed. Yay couchdb.

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