Add .args to decoded StorageKeys (#2004)

* Add .args to decoded StorageKeys

* Small opts

* Formatting

packages/api-derive/src/staking/erasExposure.ts

@@ -18,6 +18,8 @@ function queryClipped (api: ApiInterfaceRx): Observable<[EraIndex, [AccountId, E
       combineLatest([
         of(allPoints),
         combineLatest(
+          // we could just do entries over the full set, however the resultset can be quite large - split it into
+          // batches - may need to re-visit this, or alternatively use pages keys for exceptionally large sets
           allPoints.map(({ era }): Observable<[StorageKey, Exposure][]> =>
             api.query.staking.erasStakersClipped.entries(era)
           )
@@ -28,7 +30,7 @@ function queryClipped (api: ApiInterfaceRx): Observable<[EraIndex, [AccountId, E
       allPoints.map(({ era }, index): [EraIndex, [AccountId, Exposure][]] => [
         era,
         erasStakers[index].map(([key, exposure]): [AccountId, Exposure] => [
-          api.registry.createType('AccountId', key.toU8a().slice(-32)),
+          key.args[1] as AccountId,
           exposure
         ])
       ])

packages/api-derive/src/staking/validators.ts

@@ -20,10 +20,7 @@ function queryNextStakers (api: ApiInterfaceRx): Observable<AccountId[]> {
       api.query.staking.erasStakers.entries(activeEra.addn(1))
     ),
     map((entries): AccountId[] =>
-      // key is from concat with AccountId bytes right at the end
-      entries.map(([key]): AccountId =>
-        api.registry.createType('AccountId', key.toU8a().slice(-32))
-      )
+      entries.map(([key]): AccountId => key.args[1] as AccountId)
     )
   );
 }