Migrate pallet-example-offchain-worker to TransactionExtension API

prdoc/pr_10716.prdoc

@@ -0,0 +1,21 @@
+title: Migrate `pallet-example-offchain-worker` to use `TransactionExtension` API
+
+doc:
+- audience: Runtime Dev
+  description: |-
+    Migrates `pallet-example-offchain-worker` from the deprecated `ValidateUnsigned` trait
+    to the modern `TransactionExtension` API using the `#[pallet::authorize]` attribute.
+
+    This change demonstrates how to validate unsigned transactions using the new approach,
+    which provides better composability and flexibility for transaction validation.
+
+    The pallet now uses `#[pallet::authorize]` on unsigned transaction calls to validate:
+    - Block number is within the expected window
+    - Price data is valid
+    - For signed payloads, signature verification using the authority's public key
+
+    This serves as a reference example for other pallets migrating away from `ValidateUnsigned`.
+
+crates:
+- name: pallet-example-offchain-worker
+  bump: major

substrate/frame/examples/offchain-worker/README.md

@@ -7,9 +7,9 @@ concepts, APIs and structures common to most offchain workers.
 Run `cargo doc --package pallet-example-offchain-worker --open` to view this module's
 documentation.
 
-- [`pallet_example_offchain_worker::Trait`](./trait.Trait.html)
+- [`Config`](./trait.Config.html)
 - [`Call`](./enum.Call.html)
-- [`Module`](./struct.Module.html)
+- [`Pallet`](./struct.Pallet.html)
 
 **This pallet serves as an example showcasing Substrate off-chain worker and is not meant to be
 used in production.**
@@ -19,11 +19,26 @@ used in production.**
 In this example we are going to build a very simplistic, naive and definitely NOT
 production-ready oracle for BTC/USD price.
 Offchain Worker (OCW) will be triggered after every block, fetch the current price
-and prepare either signed or unsigned transaction to feed the result back on chain.
+and prepare either signed or general transaction to feed the result back on chain.
 The on-chain logic will simply aggregate the results and store last `64` values to compute
 the average price.
 Additional logic in OCW is put in place to prevent spamming the network with both signed
-and unsigned transactions, and custom `UnsignedValidator` makes sure that there is only
-one unsigned transaction floating in the network.
+and general transactions. The pallet uses the `#[pallet::authorize]` attribute to validate
+general transactions, ensuring that only one general transaction can be accepted per
+`AuthorizedTxInterval` blocks.
+
+## General Transaction Validation
+
+This pallet demonstrates how to validate general transactions using the modern
+`#[pallet::authorize]` attribute instead of the deprecated `ValidateUnsigned` trait.
+
+The `#[pallet::authorize]` attribute is used on the general transaction calls:
+- `submit_price_authorized` - Validates a simple general transaction
+- `submit_price_authorized_with_signed_payload` - Validates a general transaction with a signed payload
+
+The authorization logic checks:
+1. Block number is within the expected window (via `NextAuthorizedAt` storage)
+2. The price data is valid
+3. For signed payloads, verifies the signature using the authority's public key
 
 License: MIT-0