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substratepolkadot-js

How to query substrate storage via `.entries` for partial items

how can i query the storage via .entries when i know the list of the IDs which are used to store the data?

snippet from decl_storage

/// PoE Proofs
Proofs get(fn proofs): map hasher(blake2_128_concat) GenericId=> ProofInfo<Proof, T::AccountId, T::BlockNumber>;

typescript code where i am trying to get the only few entries

type IncomingParam = [StorageKey, ProofInfo]
type SnGenericIds = GenericId[]
export async function getAll (
  items: SnGenericIds = []
): Promise<IncomingParam[]> {
  const api = getApi()
  return await api.query.poe.proofs.entries(items)
}
// items is  [ '0x6261666b313332313365616465617364' ]

when i use the polkadot.js app in the browser and pass that ID i get the record and only one, the above TS code returns ALL the records, i've checked https://polkadot.js.org/api/start/api.query.other.html#map-keys-entries and if i understand correctly above code should. work

i know of the multi but i'd like to use this method to get all or some, is that even possible?

Solution

  • the .entries(args) is only possible to use and filter with the double_map where the args is a single string that matches the first argument of the double_map

    The rust code above does not have filtering thus the RPC and the API will retrieve all entries.

    so the rust code would be following:

    /// PoE Proofs
pub Proofs get(fn proofs): double_map hasher(blake2_128_concat) GenericId, hasher(twox_64_concat) T::AccountId => ProofInfo<Proof, T::AccountId, T::BlockNumber>;

    this allows filtering using the following approach

    api.query.poe.proofs.entries('0x1231233132312')

    Additional info can be found here