Functional JS API Requests -Get Exchange Rates

get-exchange-rates.ts

const getExchangeRatesForCountry = (countryCode: CountryCode) =>
  pipe(
    // tryCatch transforms our Promise that may reject to a Promise that never rejects and returns an Either instead
    taskEither.tryCatch(
      // We need an anonymous function here because we can only use tryCatch with functions that return Lazy<Promise<any>>
      () => fetchExchangeRatesForCountry(countryCode),
      either.toError
    ),
    taskEither.chain(
      // flow => function composition (from left to right)
      // could also be written without flow() as taskEither.fromEither(validateExchangeRates(countryCode))
      // we validate our response
      // => returns Either
      // => transform Either to TaskEither
      flow(validateExchangeRates(countryCode), taskEither.fromEither)
    )
  )();