Refactor key management (#3296)

* Add Call type to extensible transactions.

Cleanup some naming

* Merge Resource and BlockExhausted into just Exhausted

* Fix

* Another fix

* Call

* Some fixes

* Fix srml tests.

* Fix all tests.

* Refactor crypto so each application of it has its own type.

* Introduce new AuthorityProvider API into Aura

This will eventually allow for dynamic determination of authority
keys and avoid having to set them directly on CLI.

* Introduce authority determinator for Babe.

Experiment with modular consensus API.

* Work in progress to introduce KeyTypeId and avoid polluting API
with validator IDs

* Finish up drafting imonline

* Rework offchain workers API.

* Rework API implementation.

* Make it compile for wasm, simplify app_crypto.

* Fix compilation of im-online.

* Fix compilation of im-online.

* Fix more compilation errors.

* Make it compile.

* Fixing tests.

* Rewrite `keystore`

* Fix session tests

* Bring back `TryFrom`'s'

* Fix `srml-grandpa`

* Fix `srml-aura`

* Fix consensus babe

* More fixes

* Make service generate keys from dev_seed

* Build fixes

* Remove offchain tests

* More fixes and cleanups

* Fixes finality grandpa

* Fix `consensus-aura`

* Fix cli

* Fix `node-cli`

* Fix chain_spec builder

* Fix doc tests

* Add authority getter for grandpa.

* Test fix

* Fixes

* Make keystore accessible from the runtime

* Move app crypto to its own crate

* Update `Cargo.lock`

* Make the crypto stuff usable from the runtime

* Adds some runtime crypto tests

* Use last finalized block for grandpa authority

* Fix warning

* Adds `SessionKeys` runtime api

* Remove `FinalityPair` and `ConsensusPair`

* Minor governance tweaks to get it inline with docs.

* Make the governance be up to date with the docs.

* Build fixes.

* Generate the inital session keys

* Failing keystore is a hard error

* Make babe work again

* Fix grandpa

* Fix tests

* Disable `keystore` in consensus critical stuff

* Build fix.

* ImOnline supports multiple authorities at once.

* Update core/application-crypto/src/ed25519.rs

* Merge branch 'master' into gav-in-progress

* Remove unneeded code for now.

* Some `session` testing

* Support querying the public keys

* Cleanup offchain

* Remove warnings

* More cleanup

* Apply suggestions from code review

Co-Authored-By: Benjamin Kampmann <ben.kampmann@googlemail.com>

* More cleanups

* JSONRPC API for setting keys.

Also, rename traits::KeyStore* -> traits::BareCryptoStore*

* Bad merge

* Fix integration tests

* Fix test build

* Test fix

* Fixes

* Warnings

* Another warning

* Bump version.

substrate/core/primitives/src/lib.rs

@@ -33,11 +33,13 @@ macro_rules! map {
 
 use rstd::prelude::*;
 use rstd::ops::Deref;
-use codec::{Encode, Decode};
 #[cfg(feature = "std")]
 use std::borrow::Cow;
 #[cfg(feature = "std")]
 use serde::{Serialize, Deserialize};
+#[cfg(feature = "std")]
+pub use serde;// << for macro
+pub use codec::{Encode, Decode};// << for macro
 
 #[cfg(feature = "std")]
 pub use impl_serde::serialize as bytes;
@@ -61,6 +63,8 @@ pub mod sandbox;
 pub mod storage;
 pub mod uint;
 mod changes_trie;
+pub mod traits;
+pub mod testing;
 
 #[cfg(test)]
 mod tests;
@@ -77,7 +81,6 @@ pub use hash_db::Hasher;
 pub use self::hasher::blake2::Blake2Hasher;
 
 /// Context for executing a call into the runtime.
-#[repr(u8)]
 pub enum ExecutionContext {
 	/// Context for general importing (including own blocks).
 	Importing,
@@ -91,6 +94,17 @@ pub enum ExecutionContext {
 	Other,
 }
 
+impl ExecutionContext {
+	/// Returns if the keystore should be enabled for the current context.
+	pub fn enable_keystore(&self) -> bool {
+		use ExecutionContext::*;
+		match self {
+			Importing | Syncing | BlockConstruction => false,
+			OffchainWorker(_) | Other => true,
+		}
+	}
+}
+
 /// Hex-serialized shim for `Vec<u8>`.
 #[derive(PartialEq, Eq, Clone)]
 #[cfg_attr(feature = "std", derive(Serialize, Deserialize, Debug, Hash, PartialOrd, Ord))]
@@ -147,7 +161,7 @@ impl<R: codec::Encode> ::std::fmt::Debug for NativeOrEncoded<R> {
 #[cfg(feature = "std")]
 impl<R: codec::Encode> NativeOrEncoded<R> {
 	/// Return the value as the encoded format.
-	pub fn as_encoded<'a>(&'a self) -> Cow<'a, [u8]> {
+	pub fn as_encoded(&self) -> Cow<'_, [u8]> {
 		match self {
 			NativeOrEncoded::Encoded(e) => Cow::Borrowed(e.as_slice()),
 			NativeOrEncoded::Native(n) => Cow::Owned(n.encode()),
@@ -199,3 +213,4 @@ impl codec::Decode for NeverNativeValue {
 		Err("`NeverNativeValue` should never be decoded".into())
 	}
 }
+