How to flatten objects in JavaScript (with or without lodash)?

Question

I have an object like

farmer:{
  name: "First Name",
  bank: {
    id: 7
  }
  certifications: [
   {
    certificateNumber: {
     id : 7
    },
    certificateNumber: {
     id : 8
    }  
   }
  ]
}

I have tried using lodash's set and unset method but that results in undefined values a lot often.I want to remove the id key from the above object completely

This is the result i want

farmer:{
  name: "First Name",
  bank: 7
  certifications: [
   {
    certificateNumber: 7,
    certificateNumber: 8 
   }
  ]
}

Answer 1

You can use lodash's _.transform() to iterate the structure recursively, and if an object has an id property, and its size (number of properties) is 1, replace the object with the id value.

Note: the certifications array is malformed and was changed to the following form [{certificateNumber:{id:7}},{certificateNumber:{id:8}}].

const fn = obj => _.transform(obj, (accumulator, value, key) => {
  let val = value

  if(_.has(value, 'id') && _.size(value) === 1) val = _.get(value, 'id')
  else if(_.isObject(value)) val = fn(value)

  accumulator[key] = val
})

const farmer = {"name":"First Name","bank":{"id":7},"certifications":[{"certificateNumber":{"id":7}},{"certificateNumber":{"id":8}}]}

const result = fn(farmer)

console.log(result)

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