How to call insert method from another method

hi guys,

sorry for the disturb I am very new in meteorjs, so please be bear on me.
I have two collection Item and Product which is one to one relationship, I know the basic insert data in collection,
All I really want to do is to simultaneously insert two inserted collections by just one form. for example when it’s normal to insert I can insert it using a form and one collection. but what I just wanted is the Item collection and Product colletion are in a form … I have tried but is not working for me, any idea for this ?

sorry for my stupid question I just want to get rid of this …

// Meteor Package(s)
import { Meteor } from 'meteor/meteor';

import { SimpleSchema } from 'meteor/aldeed:simple-schema';

// Collection
import { Items } from './items.js';
import { Products } from '/imports/api/products/products.js';

  'items.insert': function(itemData) {
    new SimpleSchema({
      name: {type: String},
      category: {type: String},
      productId: {type: String},
      productName: {type: String},
    }).validate( itemData );

    if (!this.userId) {
      throw new Meteor.Error(error.reason);

    try {
        category: itemData.category,
        productId: itemData.productId, 
        productName: itemData.productName, 
        createdAt: new Date(),
        deletedAt: null,
    } catch(error) {
      throw new Meteor.Error('error', error.error);

any solution for this problem ?

You have to call it with parameters.