added events docs

Author: duelingbenjos

.vitepress/config.mts

@@ -35,10 +35,8 @@ export default defineConfig({
                             { text: 'Cheat Sheet', link: '/smart-contracts/contract-cheat-sheet' },
                             { text: 'Context', link: '/smart-contracts/context' },
                             { text: 'Functions', link: '/smart-contracts/functions' },
-                            {
-                                text: 'Modules',
-                                collapsed: true,
-                                items: [
+                            { text: 'Events', link: '/smart-contracts/events' },
+                            { text: 'Modules', collapsed: true, items: [
                                     { text: 'Crypto', link: '/smart-contracts/modules/crypto-stdlib' },
                                     { text: 'Hashlib', link: '/smart-contracts/modules/hashlib-stdlib' },
                                     { text: 'Random', link: '/smart-contracts/modules/random-stdlib' },

src/smart-contracts/events.md

@@ -0,0 +1,53 @@
+LogEvents are used to track & index when your smart contract performs an operation.
+
+Emitted events are automatically recorded & indexed by the `Blockchain Data Service Node (BDS)` & queryable via the 
+
+# Use-cases
+
+In many situations in your app, you will want to track when something happens in your smart contract.
+
+Here are some example situations when you may want to emit an event from your contract :
+
+- When a swap occurs on a DEX.
+- When an NFT is minted.
+- When a transfer is received by a specific account.
+- When a transfer is sent from a specific account.
+- When an account approves tokens to be used by a smart contract.
+
+# Usage
+
+### Smart Contract
+
+```python
+"""
+Declare the event at the top of the contract code.
+"""
+
+TransferEvent = LogEvent(
+    event="Transfer",
+    params={
+        "from": {'type': str, 'idx': True},
+        "to": {'type': str, 'idx': True},
+        "amount": {'type': (int, float, decimal)}
+    }
+)
+
+"""
+At the end of the function in the operation you want to track,
+call the event.
+"""
+
+@export
+def transfer(amount: float, to: str):
+    ...
+    balances[ctx.caller] -= amount
+    balances[to] += amount
+
+    TransferEvent({
+        "from": ctx.caller,
+        "to": to,
+        "amount": amount
+    })
+```
+
+For info on how to query events, see the [GraphQL](../node/interfaces/graphql) docs.