feat(store,world): replace ephemeral tables with offchain tables (#…

…1558)

Co-authored-by: Kevin Ingersoll <kingersoll@gmail.com>
Co-authored-by: dk1a <dk1a@protonmail.com>

.changeset/small-chicken-repair.md

@@ -0,0 +1,20 @@
+---
+"@latticexyz/block-logs-stream": patch
+"@latticexyz/cli": patch
+"@latticexyz/common": major
+"@latticexyz/dev-tools": patch
+"@latticexyz/store-sync": patch
+"@latticexyz/store": major
+"create-mud": minor
+---
+
+What used to be known as `ephemeral` table is now called `offchain` table.
+The previous `ephemeral` tables only supported an `emitEphemeral` method, which emitted a `StoreSetEphemeralRecord` event.
+
+Now `offchain` tables support all regular table methods, except partial operations on dynamic fields (`push`, `pop`, `update`).
+Unlike regular tables they don't store data on-chain but emit the same events as regular tables (`StoreSetRecord`, `StoreSpliceStaticData`, `StoreDeleteRecord`), so their data can be indexed by offchain indexers/clients.
+
+```diff
+- EphemeralTable.emitEphemeral(value);
++ OffchainTable.set(value);
+```

docs/pages/store/advanced-features.mdx

@@ -34,9 +34,9 @@ uint256 value = CounterSingleton.get();
 
 Additional documentation on Table library generation can be found in the [`tablegen`](/store/config#store-config--tablegen-tool) section.
 
-### Ephemeral tables
+### Offchain tables
 
-Tables with the `ephemeral` property do not write to on-chain storage.
+Tables with the `offchainOnly` property do not write to on-chain storage.
 Instead, they simply emit events when records are set.
 They are useful for sending data to connected clients without the gas costs associated with a storage write.
 
@@ -52,26 +52,12 @@ export default mudConfig({
         amount: "uint32",
         receiver: "bytes32",
       },
-      ephemeral: true,
+      offchainOnly: true,
     },
   },
 });
 ```
 
-This will slightly change the generated code for the table. The `emitEphemeral` function is the main entrypoint:
-
-```solidity
-import { TradeExecuted, TradeExecutedData } from "./codegen/Tables.sol";
-
-// Emitting an ephemeral record
-TradeExecuted.emitEphemeral("0x1234", TradeExecutedData({
-  amount: 10,
-  receiver: "0x5678",
-}));
-```
-
-`get`, `set`, and `delete` functions are not generated for ephemeral tables.
-
 ### Storage hooks
 
 It is possible to register hooks on tables, allowing additional logic to be executed when records or fields are updated. Use cases include: creating indices on another table (like the `ownerOf` mapping of the ERC-721 spec as an example), emitting events on a different contract, or simply additional access-control and checks by reverting in the hook.

docs/pages/world/internals.mdx

@@ -22,7 +22,7 @@ Except `NamespaceOwner` is initialized in World's constructor, because it's need
 Internal systems are in `core` module's [implementations](https://github.com/latticexyz/mud/tree/main/packages/world/src/modules/core/implementations) folder, because they're installed by `CoreModule`.
 
 - `AccessManagementSystem` - grants/revokes access to/from resources
-- `EphemeralRecordSystem` - has `emitEphemeralRecord` for ephemeral tables
+- `BalanceTransferSystem` - handles balance transfers between namespaces and from namespaces to addresses
 - `ModuleInstallationSystem` - installation of (non-root) modules in the World
 - `StoreRegistrationSystem` - _its methods should not be used with the World framework_. Surfaces the APIs necessary to register Tables on-chain, but lacks namespaces used by World for better permission checks
 - `WorldRegistrationSystem` - surfaces the APIs necessary to register Systems, Tables, and Namespaces on-chain

examples/minimal/packages/contracts/mud.config.ts

@@ -26,7 +26,7 @@ export default mudConfig({
       valueSchema: {
         value: "string",
       },
-      ephemeral: true,
+      offchainOnly: true,
     },
     Inventory: {
       keySchema: {