The market catalogue

New in 0.3, module market, off by default. Keystone finds every shop players have set up with a Create Table Cloth and a price tag in the loaded world and lists it: what it sells, for what, how many are left, whose it is and where. Nothing is bought here; buying stays at the table cloth.

Every look-every (default 5 minutes) the block entities of loaded chunks are read for shops. A shop is remembered after its chunk unloads and forgotten when its chunk is loaded again without it, or when it has not been seen for forget-after (30 days). Only loaded chunks are ever read; nothing is loaded for the catalogue.

• /market [item] lists the nearest shops in chat (listed, default 8), with the distance and direction.
• With Keystone's client half, /market opens the catalogue: search, the item drawn as in the game, price, stock or sold out, owner, world, coordinates, distance and direction.
• Show on map (map, default auto): a waypoint in JourneyMap, else in FTB Chunks, through their public APIs when the player has one of them (neither is a dependency), and always a beam in the world and an arrow on the HUD. journeymap, ftbchunks, beam or off picks one.
• Permission keystone.market (everybody by default).

• /keystone market hide / show, standing within 8 blocks of a shop, takes it out of the catalogue or puts it back (keystone.market.manage).
• GET /v1/market (scope players.read, ?item= part of an item id) gives the same list to a website, a Discord bot or a web map.
• webhook: an https address that receives the whole catalogue as JSON (POST) when it changes, with webhook-key as a Bearer token. Empty sends nothing anywhere. Addresses inside the network are refused unless the owner sets allow-local.