Economy Core

A NeoForge 1.21.1 mod that gives a server an economy in credits, and a base other mods can build on: casinos, auction houses, bazaars.

Beta. Everything below works and has been played on a dedicated server, but things may still change before 1.0. Back up your world before updating.

What it adds

• Personal accounts in credits for every player, saved with the world. Every movement is written to a log, and whatever a crash interrupted is put back when the server starts.
• The Exchange: hand any item in for credits and buy it back later, at prices the server sets in game. Any mod's items can be currency, or plain vanilla ingots. An optional buyback surcharge keeps players from using it as free storage.
• The Shop: sells items for credits, including enchanted or renamed ones, exactly as they were listed. It never buys anything back, which makes it the place credits leave the economy.
• Price checking: before a price is accepted, it is checked against the real crafting recipes. A set of prices that would let players mint credits by crafting is refused, and the right figure is suggested.
• A staff list that runs the economy without operator rights. Moderators run the shop and the exchange; administrators also run the server bank and players' balances. Each gets a staff key of their own.

Three ways in

The exchange and the shop open the same screen whichever way a player reaches them. Each server chooses which ones it uses.

• A block to place behind a counter.
• A clerk: a shop or exchange NPC, placed with its spawn egg or /summon like any mob. Clerks stay where they are put, face the way they were placed, never take damage and never despawn, and turn their head to whoever is nearby. Each kind has three outfits of its own. Crouch and right-click one in creative with an empty hand to change its outfit; hit it in creative to remove it. Name one with a name tag.
• A command: /exchange and /shop, from anywhere. Both are on by default and can be switched off in the server config to make players walk to a counter.

A staff key opens the settings of any of them: prices, the shop's listings, the surcharge.

Commands

/economycore also covers prices (values), the buyback surcharge (spread), the shop (shop), the server bank (bank) and the staff list (staff). /economycore help lists them for whoever may use them.

Configuration

config/economycore-server.toml. A copy in a world's serverconfig folder overrides it for that world.

The server bank and the server's income

Shop sales, the exchange's buyback surcharge and any fee another mod charges are always taken from players: that is how credits leave circulation. If a mod that pays out of a bank is installed, such as a casino, that income goes into the server bank. Otherwise it simply disappears.

For mod developers

Economy Core knows nothing about the mods that use it: they depend on it, never the other way round. Everything a mod needs is in the com.github.arrivedbog593.economycore.api package, and only that package keeps its shape between releases.

• Credits: a player's balance, and what of it they can still spend.
• PlayerCommitments (from Credits.commitments()): record credits a player has promised but not yet paid, such as a bet or a bid, so the shop and the exchange cannot spend them twice.
• Settlement: move credits between any number of accounts at once. Every account is checked first, nothing moves if one cannot pay, and the whole movement is logged and recovered after a crash.
• Bank: the server's own account. A mod that pays out of it switches it on with Bank.enable(modId) while it loads, and declares what it owes with Bank.promise(...) so staff withdrawals never dip into it.
• TransactionType: register your own kinds of movement for the log with TransactionType.register(code, recoverable) from your mod's constructor.
• Staff and StaffRank: whether a player is staff, and whether an item is a staff key.
• CreditFormat: credits written the way the rest of the mod writes them.

All of it is server-thread only.

Depending on it

repositories {
    maven { url = "https://cursemaven.com" }
}

dependencies {
    implementation "curse.maven:economy-core-1775541:<fileId>"
}

Replace <fileId> with the file of the version you want: it is the number at the end of that file's page on CurseForge.

Building

./gradlew build
./gradlew publishToMavenLocal   # for mods that depend on it, during development

License

MIT.