Readers

A reader method is immutable, so any modifications you make to state are ignored.

A reader method is passed a context of type ReaderContext. A ReaderContext can only be used to make calls to other reader methods.

Here's an example of a reader method called Balance on our Account state that returns the account's current balance:

Python

from bank.v1.bank_rbt import Account

class AccountServicer(Account.Servicer):

    async def Balance(
        self,
        context: ReaderContext,
        request: BalanceRequest,
    ) -> BalanceResponse:
        return BalanceResponse(balance=self.state.balance)

TypeScript

Object literal

import { Account } from "../../api/bank/v1/account_rbt.js";

const accountServicer = Account.servicer({
  balance: async (
    context: ReaderContext,
    request: Account.BalanceRequest
  ): Promise<Account.PartialBalanceResponse> => {
    return { balance: state.balance };
  },
});

Class

import { Account } from "../../api/bank/v1/account_rbt.js";

class AccountServicer extends Account.Servicer {
  async balance(
    context: ReaderContext,
    request: Account.BalanceRequest
  ): Promise<Account.PartialBalanceResponse> {
    return { balance: this.state.balance };
  }
}