Recipe loading conditions

We could extend the recipe json format to allow conditionally skipping the loading of some recipes.

Example use case: loading certus quartz crystal -> certus quartz dust grinding recipes when AE2 is loaded.

A possible extension could look like this:

// Standard MI recipe format
{
  "type": "modern_industrialization:macerator",
  "eu": 2,
  "duration": 200,
  "item_inputs": { "tag": "c:certus_quartz_crystals" },
  "item_outputs": { "item": "appliedenergistics2:certus_quartz_dust" },
// Additional conditions, the recipe will be skipped if the conditions fail.
  "fabric:conditions": { "mod": "appliedenergistics2" }
}

The challenge is picking the exact format, designing an API that allows defining custom conditions and providing a set of useful conditions (mod loaded, AND, OR, others?).

[warjort]

Perhaps a "skipping recipe X because recipe conditions <json of the conditions here> are not satisfied." 
Well I don't want to have 100s of "failed to load recipe" errors just because some mod was missing.

You can probably put the failed ones in a HashSet/Map and print a summary? JsonElement and its derivatives implement equals() and hashCode() like the java collection framework. 100 recipes not loaded because {"mod_loaded": "foobar"} is false

DEBUG log could be useful though. 

Good luck getting a player to enable debug if your recipes aren’t appearing in their environment. 😃

[Technici4n]

Hmmm yes I meant JsonElement. 😄

Is this still going to work when Mojang move to Codecs for the whole datapack? I guess operating before the parsing is ok.

If that happens we’d probably get rid of the API, or replace it with a codec equivalent.

How will this interact with what KubeJS (and other mods) do to the recipes? https://github.com/KubeJS-Mods/KubeJS/blob/main/common/src/main/java/dev/latvian/kubejs/mixin/common/RecipeManagerMixin.java Note the ci.cancel() at priority 1100 to stop the vanilla code reparsing them.

RebornCore has a similar system and it works with KubeJS. I think the priority of 1100 is to run after RC’s handler, so if we use the default priority we should be fine. Will obviously test it in production (i.e. AOF4).