# mapLoginConfigRulesToAuthDescriptorRules · FT4 TypeScript client · Chromia Docs (concept)

> mapLoginConfigRulesToAuthDescriptorRules(
    rules: LoginConfigRules | AuthDescriptorRules ,
    getBlockHeight: () => Promise<number>,
): Promise< AuthDe

Source: https://docs.chromia.com/pages/ft4-ts-client/functions/authentication.mapLoginConfigRulesToAuthDescriptorRules/

Function

# mapLoginConfigRulesToAuthDescriptorRules

* ```signature
  mapLoginConfigRulesToAuthDescriptorRules(
      rules: LoginConfigRules | AuthDescriptorRules,
      getBlockHeight: () => Promise<number>,
  ): Promise<AuthDescriptorRules>
  ```

  Maps list of login config rules to auth descriptor rules.

  For example,
  null => null
  lessThan(relativeBlockTime(10)) => lessThan(blockTime(Date.now()+10))
  lessThan(opCount(10)) => lessThan(opCount(10))
  lessThan(relativeBlockHeight(10)) => lessThan(blockHeight(currentBlockHeight+10))
  ["and", loginRule1, authDescRule2] => ["and", authDescRule1, authDescRule2]

  #### Parameters

  + rules: [LoginConfigRules](https://docs.chromia.com/pages/ft4-ts-client/types/authentication.LoginConfigRules/) | [AuthDescriptorRules](https://docs.chromia.com/pages/ft4-ts-client/types/accounts.AuthDescriptorRules/)

    a list of login config rules
  + getBlockHeight: () => Promise<number>

    a function which returns the current block height of the chain.
    It allows caching

  #### Returns Promise<[AuthDescriptorRules](https://docs.chromia.com/pages/ft4-ts-client/types/accounts.AuthDescriptorRules/)>

  a list of auth descriptor rules

[View this page on docs.chromia.com](https://docs.chromia.com/pages/ft4-ts-client/functions/authentication.mapLoginConfigRulesToAuthDescriptorRules.html)Generated API reference, mirrored from the live docs