Bugfix: Return _id as ObjectId from cache

[tenorok]

Despite the use of lean() mongoose returns _id field as instance of ObjectId. But in cached result this field returned as a string.

[tenorok]

@boblauer what do you think?

[tenorok]

@boblauer pay attention please :-)

[aalfiann]

your code seems broken, have you try npm run lint ?

but your idea is great, I agree with this, the _id must return back as ObjectId from cache result.

[aalfiann]

For best perfomance, you have to use for loop than map.

• for is faster than forEach.
• forEach is faster than map.

you must consider of this because cachedResults may have big data array.

[tenorok]

@aalfiann you're fully right about performance, I just tried to follow current codestyle. In the latest commit I've remake realization to more faster.