How to handle null values with lodash

Question

This is simple json

  {
    home: 68
    id: 1
    name: "RL Conference Room"
    nickname: null
    setpoint: 32.34
    sleep: 58
  }

When I get empty key this lodash function works

_.get(room, 'keyName', 'whenKeyNotFound')

But as you can see above i am getting null value in nickname So I want to replace it with name but this doesn't work.

_.get(room, 'nickname', 'name')

Is there any function in lodash which does the trick?

Thank you!!!

Answer 1

In one level scenario and since (in your case) null is also an undesired result it seems you are better of without lodash and simply do this:

room.nickname || room.name 

It would actually be shorter and achieve the same result in your case.

You could also do:

let name = _.defaultTo(room.nickname, room.name)

_.defaultTo to protects you from null, NaN and undefined

So in the case above you would get the obj.name but if you have nickname set you would get that.

In scenarios where you have a long path you can utilize _.isEmpty in a custom function like this:

const getOr = (obj, path, def) => {
    var val = _.get(obj, path)
    return _.isEmpty(val) ? def : val
}

This will handle your null as well as other scenarios as per _.isEmpty docs.

You can simply then use as:

getOr(room, 'nickname', room.name)

And you can nest it:

getOr(room, 'nickname', getOr(room, 'name', 'N/A'))

Answer 2

You can rely on the fact that null, undefined, etc. are falsy, and use the || operator.

_.get(room, 'nickname') || _.get(room, 'name')

Answer 3

Since null is falsy, you can do

_.get(room, 'nickname') || 'name'

.get only returns the third argument if the result is undefined

see: https://lodash.com/docs/4.17.10#get