Parsing and Validating Request Paths in Middleware

const req = yield* HttpServerRequest.HttpServerRequest
const appID =
  pipe(
    req.url,
    O.fromNullable,
    O.flatMap(
      S.decodeOption(
        S.split('/').pipe(
          S.compose(
            S.Tuple(S.Literal(''), S.Literal('api'), S.Literal('apps'), AppID, S.Literal('users')),
          ),
        ),
      ),
    ),
    O.map(([, , , id]) => id),
  )