Luke Schoen
9eb0a392af
* Update example-offchain-worker to include missing implementation for TestAuthId i tried to incorporate the off-chain worker callback demo as a custom pallet of my own Substrate-based blockchain implementation that's provided at the following links * https://www.parity.io/blog/substrate-off-chain-workers-secure-and-efficient-computing-intensive-tasks/ * https://gnunicorn.github.io/substrate-offchain-cb/ but when i build the code with `cargo build --release`, it gave me an error: ``` error[E0277]: the trait bound `AuthorityId: AppCrypto<MultiSigner, MultiSignature>` is not satisfied --> /Users/me/my_repo/node/runtime/src/lib.rs:1172:5 | 1172 | type AuthorityId = AuthorityId; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `AppCrypto<MultiSigner, MultiSignature>` is not implemented for `AuthorityId` | note: required by a bound in `offchaincb::Config::AuthorityId` --> /Users/me/my_repo/node/pallets/offchaincb/src/lib.rs:169:21 | 169 | type AuthorityId: AppCrypto<Self::Public, Self::Signature>; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `offchaincb::Config::AuthorityId` ``` where in my custom pallet i have: pallets/offchaincb/src/lib.rs ``` ... use offchaincb::{ crypto::{ TestAuthId, }, }; ... parameter_types! { pub const GracePeriod: BlockNumber = 1 * MINUTES; pub const UnsignedInterval: BlockNumber = 1 * MINUTES; pub const UnsignedPriority: BlockNumber = 1 * MINUTES; } impl offchaincb::Config for Runtime { type AuthorityId = TestAuthId; type Call = Call; type Currency = Balances; type Event = Event; type GracePeriod = GracePeriod; type UnsignedInterval = UnsignedInterval; type UnsignedPriority = UnsignedPriority; } ... ``` then i found another different off-chain workers Substrate Recipe demo from Jimmy Chu https://github.com/jimmychu0807/recipes/blob/master/pallets/ocw-demo/src/lib.rs#L73 which had an extra implementation for TestAuthId here https://github.com/jimmychu0807/recipes/blob/master/pallets/ocw-demo/src/lib.rs#L73, and when i added that it overcame the error. so i think this change should be included in the Substrate repository * Fix indentation * Fix formatting * Swap order
Offchain Worker Example Module
The Offchain Worker Example: A simple pallet demonstrating concepts, APIs and structures common to most offchain workers.
Run cargo doc --package pallet-example-offchain-worker --open to view this module's
documentation.
Overview
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.
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.
License: Unlicense