Dedupe progress extraction (#4322)

* Dedupe progress extraction

* Adjust

packages/api-derive/src/elections/info.ts

@@ -54,7 +54,8 @@ function getConstants (api: ApiInterfaceRx, elections: string | null): Partial<D
     : {};
 }
 
-function queryElections (api: ApiInterfaceRx): Observable<DeriveElectionsInfo> {
+function getModules (api: ApiInterfaceRx): [string, string | null] {
+  const [council] = api.registry.getModuleInstances(api.runtimeVersion.specName.toString(), 'council') || ['council'];
   const elections = api.query.phragmenElection
     ? 'phragmenElection'
     : api.query.electionsPhragmen
@@ -62,33 +63,8 @@ function queryElections (api: ApiInterfaceRx): Observable<DeriveElectionsInfo> {
       : api.query.elections
         ? 'elections'
         : null;
-  const [council] = api.registry.getModuleInstances(api.runtimeVersion.specName.toString(), 'council') || ['council'];
 
-  return (
-    elections
-      ? api.queryMulti<[Vec<AccountId>, Vec<Candidate>, Vec<Member>, Vec<Member>]>([
-        api.query[council].members,
-        api.query[elections].candidates,
-        api.query[elections].members,
-        api.query[elections].runnersUp
-      ])
-      : combineLatest([
-        api.query[council].members<Vec<AccountId>>(),
-        of<Candidate[]>([]),
-        of<Member[]>([]),
-        of<Member[]>([])
-      ])
-  ).pipe(
-    map(([councilMembers, candidates, members, runnersUp]): DeriveElectionsInfo => ({
-      ...getConstants(api, elections),
-      candidateCount: api.registry.createType('u32', candidates.length),
-      candidates: candidates.map(getCandidate),
-      members: members.length
-        ? members.map(getAccountTuple).sort(sortAccounts)
-        : councilMembers.map((accountId): [AccountId, Balance] => [accountId, api.registry.createType('Balance')]),
-      runnersUp: runnersUp.map(getAccountTuple).sort(sortAccounts)
-    }))
-  );
+  return [council, elections];
 }
 
 /**
@@ -105,5 +81,33 @@ function queryElections (api: ApiInterfaceRx): Observable<DeriveElectionsInfo> {
  * ```
  */
 export function info (instanceId: string, api: ApiInterfaceRx): () => Observable<DeriveElectionsInfo> {
-  return memo(instanceId, (): Observable<DeriveElectionsInfo> => queryElections(api));
+  return memo(instanceId, (): Observable<DeriveElectionsInfo> => {
+    const [council, elections] = getModules(api);
+
+    return (
+      elections
+        ? api.queryMulti<[Vec<AccountId>, Vec<Candidate>, Vec<Member>, Vec<Member>]>([
+          api.query[council].members,
+          api.query[elections].candidates,
+          api.query[elections].members,
+          api.query[elections].runnersUp
+        ])
+        : combineLatest([
+          api.query[council].members<Vec<AccountId>>(),
+          of<Candidate[]>([]),
+          of<Member[]>([]),
+          of<Member[]>([])
+        ])
+    ).pipe(
+      map(([councilMembers, candidates, members, runnersUp]): DeriveElectionsInfo => ({
+        ...getConstants(api, elections),
+        candidateCount: api.registry.createType('u32', candidates.length),
+        candidates: candidates.map(getCandidate),
+        members: members.length
+          ? members.map(getAccountTuple).sort(sortAccounts)
+          : councilMembers.map((a): [AccountId, Balance] => [a, api.registry.createType('Balance')]),
+        runnersUp: runnersUp.map(getAccountTuple).sort(sortAccounts)
+      }))
+    );
+  });
 }

packages/api-derive/src/session/eraLength.ts

@@ -1,17 +0,0 @@
-// Copyright 2017-2021 @polkadot/api-derive authors & contributors
-// SPDX-License-Identifier: Apache-2.0
-
-import type { Observable } from 'rxjs';
-import type { ApiInterfaceRx } from '@polkadot/api/types';
-import type { BlockNumber } from '@polkadot/types/interfaces';
-
-import { map } from 'rxjs';
-
-import { memo } from '../util';
-
-export function eraLength (instanceId: string, api: ApiInterfaceRx): () => Observable<BlockNumber> {
-  return memo(instanceId, (): Observable<BlockNumber> =>
-    api.derive.session.info().pipe(
-      map((info) => info.eraLength)
-    ));
-}

packages/api-derive/src/session/eraProgress.ts

@@ -1,17 +0,0 @@
-// Copyright 2017-2021 @polkadot/api-derive authors & contributors
-// SPDX-License-Identifier: Apache-2.0
-
-import type { Observable } from 'rxjs';
-import type { ApiInterfaceRx } from '@polkadot/api/types';
-import type { BlockNumber } from '@polkadot/types/interfaces';
-
-import { map } from 'rxjs';
-
-import { memo } from '../util';
-
-export function eraProgress (instanceId: string, api: ApiInterfaceRx): () => Observable<BlockNumber> {
-  return memo(instanceId, (): Observable<BlockNumber> =>
-    api.derive.session.progress().pipe(
-      map((info) => info.eraProgress)
-    ));
-}

packages/api-derive/src/session/index.ts

@@ -1,9 +1,6 @@
 // Copyright 2017-2021 @polkadot/api-derive authors & contributors
 // SPDX-License-Identifier: Apache-2.0
 
-export * from './eraLength';
-export * from './eraProgress';
 export * from './indexes';
 export * from './info';
 export * from './progress';
-export * from './sessionProgress';

packages/api-derive/src/session/progress.ts

@@ -4,7 +4,7 @@
 import type { Observable } from 'rxjs';
 import type { ApiInterfaceRx } from '@polkadot/api/types';
 import type { Option, u64 } from '@polkadot/types';
-import type { SessionIndex } from '@polkadot/types/interfaces';
+import type { BlockNumber, SessionIndex } from '@polkadot/types/interfaces';
 import type { DeriveSessionInfo, DeriveSessionProgress } from '../types';
 
 import { combineLatest, map, of, switchMap } from 'rxjs';
@@ -15,6 +15,15 @@ type ResultSlotsNoSession = [u64, u64, u64];
 type ResultSlots = [u64, u64, u64, Option<SessionIndex>];
 type ResultSlotsFlat = [u64, u64, u64, SessionIndex];
 
+function withProgressField (field: 'eraLength' | 'eraProgress' | 'sessionProgress'): (instanceId: string, api: ApiInterfaceRx) => () => Observable<BlockNumber> {
+  return (instanceId: string, api: ApiInterfaceRx) =>
+    memo(instanceId, (): Observable<BlockNumber> =>
+      api.derive.session.progress().pipe(
+        map((info) => info[field])
+      )
+    );
+}
+
 function createDerive (api: ApiInterfaceRx, info: DeriveSessionInfo, [currentSlot, epochIndex, epochOrGenesisStartSlot, activeEraStartSessionIndex]: ResultSlotsFlat): DeriveSessionProgress {
   const epochStartSlot = epochIndex.mul(info.sessionLength).iadd(epochOrGenesisStartSlot);
   const sessionProgress = currentSlot.sub(epochStartSlot);
@@ -77,3 +86,7 @@ export function progress (instanceId: string, api: ApiInterfaceRx): () => Observ
       : queryAura(api)
   );
 }
+
+export const eraLength = withProgressField('eraLength');
+export const eraProgress = withProgressField('eraProgress');
+export const sessionProgress = withProgressField('sessionProgress');

packages/api-derive/src/session/sessionProgress.ts

@@ -1,17 +0,0 @@
-// Copyright 2017-2021 @polkadot/api-derive authors & contributors
-// SPDX-License-Identifier: Apache-2.0
-
-import type { Observable } from 'rxjs';
-import type { ApiInterfaceRx } from '@polkadot/api/types';
-import type { BlockNumber } from '@polkadot/types/interfaces';
-
-import { map } from 'rxjs';
-
-import { memo } from '../util';
-
-export function sessionProgress (instanceId: string, api: ApiInterfaceRx): () => Observable<BlockNumber> {
-  return memo(instanceId, (): Observable<BlockNumber> =>
-    api.derive.session.progress().pipe(
-      map((info) => info.sessionProgress)
-    ));
-}