Initial: Offchain Workers (#1942)

* Refactor state-machine stuff.

* Fix tests.

* WiP

* WiP2

* Service support for offchain workers.

* Service support for offchain workers.

* Testing offchain worker.

* Initial version working.

* Pass side effects in call.

* Pass OffchainExt in context.

* Submit extrinsics to the pool.

* Support inherents.

* Insert to inherents pool.

* Inserting to the pool asynchronously.

* Add test to offchain worker.

* Implement convenience syntax for modules.

* Dispatching offchain worker through executive.

* Fix offchain test.

* Remove offchain worker from timestamp.

* Update Cargo.lock.

* Address review comments.

* Use latest patch version for futures.

* Add CLI parameter for offchain worker.

* Fix compilation.

* Fix test.

* Fix extrinsics format for tests.

* Fix RPC test.

* Bump spec version.

* Fix executive.

* Fix support macro.

* Address grumbles.

* Bump runtime

substrate/node-template/runtime/src/lib.rs

@@ -14,7 +14,7 @@ use primitives::bytes;
 use primitives::{ed25519, OpaqueMetadata};
 use runtime_primitives::{
 	ApplyResult, transaction_validity::TransactionValidity, generic, create_runtime_str,
-	traits::{self, BlakeTwo256, Block as BlockT, StaticLookup, Verify}
+	traits::{self, NumberFor, BlakeTwo256, Block as BlockT, StaticLookup, Verify}
 };
 use client::{
 	block_builder::api::{CheckInherentsResult, InherentData, self as block_builder_api},
@@ -182,7 +182,7 @@ impl sudo::Trait for Runtime {
 }
 
 /// Used for the module template in `./template.rs`
-impl template::Trait for Runtime { 
+impl template::Trait for Runtime {
 	type Event = Event;
 }
 
@@ -280,4 +280,10 @@ impl_runtime_apis! {
 			Aura::slot_duration()
 		}
 	}
+
+	impl offchain_primitives::OffchainWorkerApi<Block> for Runtime {
+		fn offchain_worker(n: NumberFor<Block>) {
+			Executive::offchain_worker(n)
+		}
+	}
 }