Consolidate caches and create a _cache folder for *all* to use.

[envygeeks]

Today we did an audit for our biggest Jekyll site and noticed it has like 8 cache folders, this is pretty big and unwieldy, it also makes it harder for us to control the caching on our build servers. We should create a _cache folder and consolidate all Jekyll caching into that folder, and then ask plugin authors to place their caches in that folder too with or without prefixes. Exp:

• _cache/jekyll/incremental
• _cache/jekyll-assets/assets
• _cache/jekyll/sass

Now cleanup went from "let me figure out what is what" to rm -rf _cache

[envygeeks]

/cc @jekyll/core

[parkr]

Let's add the removal of these caches to the jekyll clean command.

[alfredxing]

👍 Good idea! It'd be easier for users in terms of ignoring these files for source control as well.

[parkr]

Are any sites using _cache for content? That's what worries me here.

[envygeeks]

@parkr make it configurable then, out of all the configuration options that a system should have, where it caches is a high-priority unless it uses system caches, and especially if it uses local directory caching. We allow it on Jekyll-Assets which gives users flexibility on where they place their cache and how, it's not a bad idea for Jekyll and I don't know the YACO applies here because for people like me who build hundreds of sites putting our caches in a global directory and controlling them gives us much more flexibility in our build systems, how we build all that, and it gives the average user more flexibility in how dirty their folder is at the root.

[envygeeks]

Reopening at the request of @nhoizey
/cc @parkr @jekyll/core @jekyll/ecosystem

[envygeeks]

Oops, thought I did reopen it, thanks for doing it @parkr.

[mattr-]

👍 for this idea from me.

[pathawks]

I very much approve of this idea 👍

Are any sites using _cache for content?

Yeah, how would this work? Don’t want anybody to upgrade without reading the docs and end up having some of their data "cleaned" away by mistake.

[envygeeks]

I think we would have to do a pre-4.0 pre-flight warning, to let people we know that we are implementing a new folder and that it could be destroyed by "jekyll clean" but we could always use .jekyll-cache or something like that which in theory shouldn't conflict and if it does I'm okay with that the latter folder conflicting because one would expect any .jekyll prefixed folder to be reserved.

[envygeeks]

Regardless of this change I think a pre-flight warning on 4.0 is a good idea, when we moved to Jekyll 3 we got so many tickets by people taken aback from changes that were in the works for months, so we should really start doing random "master branch" feature posts to start preparing people to what's coming up.

[nhoizey]

Can we agree on the .jekyll-cache name, so that plugins authors can start align, even if there are still no tools in Jekyll to manipulate/clean it?

[envygeeks]

@nhoizey I can agree to .jekyll-cache and will even default Jekyll-Assets 3 to using that name.

[nhoizey]

@envygeeks great, I'll start using it as well.