how to iterate a type from typescript and use it to form another type

I wrap my api request to an obj with moduleName and apiName with url values like

const modules = {
  cart: {
    cart: '/shoppingCart',
    goodsSkus: '/shoppingCart/goodsSkus',
  },
}

And i use a helperFunction below to convert it to my apiActionObject

now this is from from js file, because my ts file is on error.

let apiAction = {};
Object.keys(modules).forEach((modulesName) => {
  apiAction[modulesName] = {};
  Object.keys(modules[modulesName]).forEach((apiName) => {
    apiAction[modulesName][apiName] = async ({
      method = 'get',
      id,
      resource,
      ...options
    } = {}) => {
      let url = modules[modulesName][apiName];
      url += `${id !== undefined ? `/${id}` : ''}${
        resource ? `/${resource}` : ''
      }`;

      return service({ url, method, ...options });
    };
  });
});

And i try to make my ApiAction type using code below, everythink looks well.

type ModuleName = keyof typeof modules;
type ApiName<T extends ModuleName> = keyof typeof modules[T];

type ApiAction = {
  [moduleName in ModuleName]: {
    [apiName in ApiName<moduleName>]: (
      arg: ApiServiceParams<any, any>
    ) => Promise<any>;
  };
};

Then i try to add some more specific type in ApiServiceParams, below code goes wrong

// requestAndResponseType
type _RRType = {
  [moduleName in ModuleName]: {
    [apiName in ApiName<moduleName>]: {
      req: any;
      res: any;
    };
  };
};

interface RRType extends _RRType {
  cart: {
    cart: {
      req: Api.GetPvStatsUsingGetParams;
      res: Api.AfterSaleTicketPageResponse;
    };
    goodsSkus: {
      req: Api.GetPvStatsUsingGetParams;
      res: Api.AfterSaleTicketPageResponse;
    };
  };
}


type TypeWorksFine = RRType['goods']['product']['req']; // type is any
type TypeWorksFine2 = RRType['cart']['goodsSkus']['req']; // type is Api.GetPvStatsUsingGetParams;

// https://stackoverflow.com/questions/46846669/type-key-cannot-be-used-to-index-type-object
type ApiAction = {
  [moduleName in ModuleName]: {
    [apiName in keyof RRType[moduleName]]: (
      arg: ApiServiceParams<RRType[moduleName][apiName]['req'], any>
    ) => Promise<any>;
  };
};

The code above is both type TypeWorksFine and TypeWorksFine2 works properly, but in the interation of ApiAction, it fails with error Type '"req"' cannot be used to index type 'RRType[moduleName][apiName]'.

In fact i first ran into this error when i use the key as [apiName in ApiName] as below

type ApiAction = {
  [moduleName in ModuleName]: {
    [apiName in ApiName<moduleName>]: (
      arg: ApiServiceParams<RRType[moduleName][apiName], any> // Type 'apiName' cannot be used to index type 'RRType[moduleName]'
    ) => Promise<any>;
  };
};

then i found a tip to fix this type key cannnot be used to index type object answer to solve this problem. but when i get in this problem by the req property, i can't find a way to fix.

So there is a way to iterate the type object and make the new type? Thank you in advance！

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