Expose properties and per-era preferences

src/frame/staking.rs

@@ -38,6 +38,11 @@ use std::{
     marker::PhantomData,
 };
 
+pub use pallet_staking::{
+    EraIndex,
+    StakingLedger,
+};
+
 /// A record of the nominations made by a specific account.
 #[derive(PartialEq, Eq, Clone, Encode, Decode, Debug, Ord, PartialOrd, Hash)]
 pub struct Nominations<T: Staking> {
@@ -51,6 +56,20 @@ pub struct Nominations<T: Staking> {
     pub suppressed: bool,
 }
 
+/// Similar to `ErasStakers`, this holds the preferences of validators.
+///
+/// This is keyed first by the era index to allow bulk deletion and then the stash account.
+///
+/// Is it removed after `HISTORY_DEPTH` eras.
+#[derive(Encode, Decode, Debug, Store)]
+pub struct ErasValidatorPrefsStore<T: Staking> {
+    #[store(returns = ValidatorPrefs)]
+    /// Era index
+    index: EraIndex,
+    /// Account ID
+    account_id: T::AccountId,
+}
+
 /// Information regarding the active era (era in used in session).
 #[derive(Encode, Decode, Debug, Eq, PartialEq, Ord, PartialOrd, Hash)]
 pub struct ActiveEraInfo<T: Staking> {
@@ -161,8 +180,6 @@ pub struct UnlockChunk<T: Staking> {
     pub era: T::EraIndex,
 }
 
-pub use pallet_staking::StakingLedger;
-
 /// Number of eras to keep in history.
 ///
 /// Information is kept for eras in `[current_era - history_depth; current_era]`.

src/lib.rs

@@ -35,7 +35,8 @@
     while_true,
     trivial_casts,
     trivial_numeric_casts,
-    unused_extern_crates
+    unused_extern_crates,
+    clippy::all
 )]
 #![allow(clippy::type_complexity)]
 
@@ -93,6 +94,7 @@ pub use crate::{
     rpc::{
         BlockNumber,
         ExtrinsicSuccess,
+        Properties,
     },
     runtimes::*,
     subscription::*,
@@ -161,16 +163,18 @@ impl<T: Runtime> ClientBuilder<T> {
             }
         };
         let rpc = Rpc::new(client);
-        let (metadata, genesis_hash, runtime_version) = future::join3(
+        let (metadata, genesis_hash, runtime_version, properties) = future::join4(
             rpc.metadata(),
             rpc.genesis_hash(),
             rpc.runtime_version(None),
+            rpc.properties(),
         )
         .await;
         Ok(Client {
             rpc,
             genesis_hash: genesis_hash?,
             metadata: metadata?,
+            properties: properties?,
             runtime_version: runtime_version?,
             _marker: PhantomData,
             page_size: self.page_size.unwrap_or(10),
@@ -183,6 +187,7 @@ pub struct Client<T: Runtime> {
     rpc: Rpc<T>,
     genesis_hash: T::Hash,
     metadata: Metadata,
+    properties: Properties,
     runtime_version: RuntimeVersion,
     _marker: PhantomData<(fn() -> T::Signature, T::Extra)>,
     page_size: u32,
@@ -194,6 +199,7 @@ impl<T: Runtime> Clone for Client<T> {
             rpc: self.rpc.clone(),
             genesis_hash: self.genesis_hash,
             metadata: self.metadata.clone(),
+            properties: self.properties.clone(),
             runtime_version: self.runtime_version.clone(),
             _marker: PhantomData,
             page_size: self.page_size,
@@ -258,6 +264,11 @@ impl<T: Runtime> Client<T> {
         &self.metadata
     }
 
+    /// Returns the system properties
+    pub fn properties(&self) -> &Properties {
+        &self.properties
+    }
+
     /// Fetch a StorageKey with an optional block hash.
     pub async fn fetch<F: Store<T>>(
         &self,

src/rpc.rs

@@ -96,6 +96,18 @@ impl From<u32> for BlockNumber {
     }
 }
 
+#[derive(serde::Serialize, serde::Deserialize, Debug, Clone, PartialEq, Eq)]
+#[serde(rename_all = "camelCase")]
+/// System properties for a Substrate-based runtime
+pub struct Properties {
+    /// The address format
+    pub ss58_format: u8,
+    /// The number of digits after the decimal point in the native token
+    pub token_decimals: u8,
+    /// The symbol of the native token
+    pub token_symbol: String,
+}
+
 /// Client for substrate rpc interfaces
 pub struct Rpc<T: Runtime> {
     client: Client,
@@ -208,6 +220,14 @@ impl<T: Runtime> Rpc<T> {
         Ok(metadata)
     }
 
+    /// Fetch system properties
+    pub async fn properties(&self) -> Result<Properties, Error> {
+        Ok(self
+            .client
+            .request("system_properties", Params::None)
+            .await?)
+    }
+
     /// Get a header
     pub async fn header(
         &self,

src/runtimes.rs

@@ -127,7 +127,6 @@ use crate::{
     session::Session,
     staking::Staking,
     system::System,
-    Encoded,
 };
 
 /// Runtime trait.