packages/api-derive/src/staking/erasExposure.ts
// Copyright 2017-2024 @polkadot/api-derive authors & contributors
// SPDX-License-Identifier: Apache-2.0
import type { Observable } from 'rxjs';
import type { Option, StorageKey, u32 } from '@polkadot/types';
import type { AccountId, AccountId32, EraIndex } from '@polkadot/types/interfaces';
import type { SpStakingExposure, SpStakingExposurePage } from '@polkadot/types/lookup';
import type { DeriveApi, DeriveEraExposurePaged, DeriveEraNominatorExposure, DeriveEraValidatorExposure, DeriveEraValidatorExposurePaged } from '../types.js';
import { map, of } from 'rxjs';
import { memo } from '../util/index.js';
import { getEraCache, setEraCache } from './cache.js';
import { combineEras, erasHistoricApply, singleEra } from './util.js';
type KeysAndExposures = [StorageKey<[EraIndex, AccountId]>, SpStakingExposure][];
type KeysAndExposuresPaged = [StorageKey<[u32, AccountId32, u32]>, Option<SpStakingExposurePage>][];
const CACHE_KEY = 'eraExposure';
function mapStakersClipped (era: EraIndex, stakers: KeysAndExposures): DeriveEraExposurePaged {
const nominators: DeriveEraNominatorExposure = {};
const validators: DeriveEraValidatorExposure = {};
stakers.forEach(([key, exposure]): void => {
const validatorId = key.args[1].toString();
validators[validatorId] = exposure;
exposure.others.forEach(({ who }, validatorIndex): void => {
const nominatorId = who.toString();
nominators[nominatorId] = nominators[nominatorId] || [];
nominators[nominatorId].push({ validatorId, validatorIndex });
});
});
return { era, nominators, validators };
}
function mapStakersPaged (era: EraIndex, stakers: KeysAndExposuresPaged): DeriveEraExposurePaged {
const nominators: DeriveEraNominatorExposure = {};
const validators: DeriveEraValidatorExposurePaged = {};
stakers.forEach(([key, exposureOpt]): void => {
if (exposureOpt.isSome) {
const validatorId = key.args[1].toString();
const exposure = exposureOpt.unwrap();
validators[validatorId] = exposure;
exposure.others.forEach(({ who }, validatorIndex): void => {
const nominatorId = who.toString();
nominators[nominatorId] = nominators[nominatorId] || [];
nominators[nominatorId].push({ validatorId, validatorIndex });
});
}
});
return { era, nominators, validators };
}
/**
* erasStakersClipped will be deprecated and replaced with erasStakersPaged. Therefore support is given for both
* storage queries until erasStakersClipped has been completely out of use.
*/
export function _eraExposure (instanceId: string, api: DeriveApi): (era: EraIndex, withActive?: boolean) => Observable<DeriveEraExposurePaged> {
return memo(instanceId, (era: EraIndex, withActive = false): Observable<DeriveEraExposurePaged> => {
const [cacheKey, cached] = getEraCache<DeriveEraExposurePaged>(CACHE_KEY, era, withActive);
return cached
? of(cached)
: api.query.staking.erasStakersPaged
? api.query.staking.erasStakersPaged.entries<Option<SpStakingExposurePage>>(era).pipe(
map((r) => setEraCache(cacheKey, withActive, mapStakersPaged(era, r)))
)
: api.query.staking.erasStakersClipped.entries(era).pipe(
map((r) => setEraCache(cacheKey, withActive, mapStakersClipped(era, r)))
);
});
}
export const eraExposure = /*#__PURE__*/ singleEra('_eraExposure');
export const _erasExposure = /*#__PURE__*/ combineEras('_eraExposure');
export const erasExposure = /*#__PURE__*/ erasHistoricApply('_erasExposure');