Add api.derive.accounts.flags (#2195)

* account flags in new call

* Fix

packages/api-derive/src/accounts/flags.ts

@@ -0,0 +1,69 @@
+// Copyright 2017-2020 @polkadot/api-derive authors & contributors
+// This software may be modified and distributed under the terms
+// of the Apache-2.0 license. See the LICENSE file for details.
+
+import { ApiInterfaceRx } from '@polkadot/api/types';
+import { AccountId, Address, Balance } from '@polkadot/types/interfaces';
+import { ITuple } from '@polkadot/types/types';
+import { DeriveAccountFlags } from '../types';
+
+import { Observable, combineLatest, of } from 'rxjs';
+import { map } from 'rxjs/operators';
+import { Vec } from '@polkadot/types';
+
+import { memo } from '../util';
+
+type FlagsIntermediate = [
+  Vec<ITuple<[AccountId, Balance]>> | undefined,
+  AccountId[],
+  AccountId[],
+  AccountId[],
+  AccountId | undefined
+];
+
+function isIncludedFn (accountId: AccountId | Address | string): (_: AccountId | Address |string) => boolean {
+  return function (id: AccountId | Address | string): boolean {
+    return id.toString() === accountId.toString();
+  };
+}
+
+/**
+ * @name info
+ * @description Returns account membership flags
+ */
+export function flags (api: ApiInterfaceRx): (address?: AccountId | Address | string | null) => Observable<DeriveAccountFlags> {
+  return memo((address?: AccountId | Address | string | null): Observable<DeriveAccountFlags> => {
+    const councilSection = api.query.electionsPhragmen ? 'electionsPhragmen' : 'elections';
+
+    return (
+      combineLatest([
+        address && api.query[councilSection]?.members
+          ? api.query[councilSection].members()
+          : of(undefined),
+        address && api.query.council.members
+          ? api.query.council.members()
+          : of([]),
+        address && api.query.technicalCommittee?.members
+          ? api.query.technicalCommittee.members()
+          : of([]),
+        address && api.query.society?.members
+          ? api.query.society.members()
+          : of([]),
+        address && api.query.sudo?.key
+          ? api.query.sudo.key()
+          : of(undefined)
+      ]) as Observable<FlagsIntermediate>
+    ).pipe(
+      map(([electionsMembers, councilMembers, technicalCommitteeMembers, societyMembers, sudoKey]): DeriveAccountFlags => {
+        const isIncluded = address ? isIncludedFn(address) : (): boolean => false;
+
+        return {
+          isCouncil: (electionsMembers?.map(([id]: ITuple<[AccountId, Balance]>) => id) || councilMembers || []).some(isIncluded),
+          isSociety: (societyMembers || []).some(isIncluded),
+          isSudo: sudoKey?.toString() === address?.toString(),
+          isTechCommittee: (technicalCommitteeMembers || []).some(isIncluded)
+        };
+      })
+    );
+  });
+}

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

@@ -2,6 +2,7 @@
 // This software may be modified and distributed under the terms
 // of the Apache-2.0 license. See the LICENSE file for details.
 
+export * from './flags';
 export * from './idAndIndex';
 export * from './idToIndex';
 export * from './indexToId';

packages/api-derive/src/accounts/types.ts

@@ -23,6 +23,13 @@ export interface DeriveAccountRegistration {
   judgements: RegistrationJudgement[];
 }
 
+export interface DeriveAccountFlags {
+  isCouncil: boolean;
+  isSociety: boolean;
+  isSudo: boolean;
+  isTechCommittee: boolean;
+}
+
 export interface DeriveAccountInfo {
   accountId?: AccountId;
   accountIndex?: AccountIndex;