Finds the value at key of a nested object using lodash

example.js

// here is the nested object to do the find on
{
  "level1": {
    "level2": {
      "level3": {
        "level4": {
          "level5": "value"
        }
      }
    }
  }
}

// you can pass this and it will return "value"
{
  "level4": {
    "level5": "value"
  }
}

// you can pass this and it will return null
{
  "level4": {
    "level5": "not the right value"
  }
}

// you can pass this and it will return null
{
  "level4": {
    "notRightKey": "blah"
  }
}

valueAtKeyPair.js

import _ from 'lodash'
import flatten from 'flat' // flatten nested object
import _s from 'underscore.string'


class Validate {
  
    /**
   * test to see if a key value pair is present in a [potentially] nested object
   * @param  {object}  obj [nested object]
   * @param  {object}  key [nested object representing the unique key]
   * @param  {value}   val [any value to test for]
   * @example
   * // here is the nested object to do the find on
      {
        "level1": {
          "level2": {
            "level2a": "nesting",
            "level2b": "nesting again",
            "level3": {
              "level4": {
                "level5": "value"
              }
            }
          }
        }
      }

      // you can pass this and it will return "value"
      {
        "level4": {
          "level5": "value"
        }
      }

      // you can pass this and it will return null
      {
        "level4": {
          "level5": "not the right value"
        }
      }

      // you can pass this and it will return null
      {
        "level4": {
          "notRightKey": "value"
        }
      }
   * @return {Boolean}     [whether the key-value pair exists]
   */
  hasKeyValuePair(findObj) {
    
    // flatten nested object and key
    const flatObj = flatten(this.obj)
    const flatFindObj = flatten(findObj)

    // create array of keys
    const objKeys = Object.keys(flatObj)
    const findObjKeys = Object.keys(flatFindObj)

    // find where key is in nested obj
    const keyTree = _(objKeys).find(nestedKey => {
      // return the nestedKey string that includes key
      return (_s.include(nestedKey, findObjKeys))
    })

    // return if no keyTree found
    if (!keyTree || is.empty(keyTree)) return false

    // find the value of the key
    const keyVal = _(this.obj).get(keyTree)
    const findVal = _(findObj).get(findObjKeys[0])

    // return true if values are equal
    return (keyVal === findVal)
  }
}