Lodash removes items recursively

Question

Given this JSON object, how does lodash remove the reach value from objects?

 { total: 350, SN1: { reach: 200, engagementRate: 1.35 }, SN2: { reach: 150, engagementRate: 1.19 } } 

I am trying to iteratively delete (), but I always get an undefined object in return, so I'm sure I'm doing it wrong. This is also the first time I use lodash, so this may be an actual problem.

Can anyone help?

Answer 1

_.transform() an object to another object, and when passing values ​​to a new object, check if this value is an object, and if it has a reach property, and if it uses _.omit() to get a new object without reach :

 var obj = { total: 350, SN1: { reach: 200, engagementRate: 1.35 }, SN2: { reach: 150, engagementRate: 1.19 } }; var result = _.transform(obj, function(result, value, key) { result[key] = _.isObject(value) && `reach` in value ? _.omit(value, 'reach') : value; }); console.log(result); 

 <script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.15.0/lodash.min.js"></script> 

And if you need a recursive solution that will handle several levels of nested objects, here is deepOmit , which uses the same idea, but without _.omit , and can be used to delete several keys (see comments in the code)

 var obj = { total: 350, SN1: { reach: 200, engagementRate: 1.35, DEEP_SN1: { reach: 200, engagementRate: 1.35 } }, SN2: { reach: 150, engagementRate: 1.19 } }; function deepOmit(obj, keysToOmit) { var keysToOmitIndex = _.keyBy(Array.isArray(keysToOmit) ? keysToOmit : [keysToOmit] ); // create an index object of the keys that should be omitted function omitFromObject(obj) { // the inner function which will be called recursivley return _.transform(obj, function(result, value, key) { // transform to a new object if (key in keysToOmitIndex) { // if the key is in the index skip it return; } result[key] = _.isObject(value) ? omitFromObject(value) : value; // if the key is an object run it through the inner function - omitFromObject }) } return omitFromObject(obj); // return the inner function result } console.log(deepOmit(obj, 'reach')); // you can use a string for a single value console.log(deepOmit(obj, ['reach', 'engagementRate'])); // you can use an array of strings for multiple values 

 <script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.15.0/lodash.min.js"></script> 

Answer 2

It seems that there is no deep skip , but you can iterate over all the keys in the object and remove reach from the nested objects, recursively:

 function omitDeep(obj) { _.forIn(obj, function(value, key) { if (_.isObject(value)) { omitDeep(value); } else if (key === 'reach') { delete obj[key]; } }); } 

 var obj = { total: 350, SN1: { reach: 200, engagementRate: 1.35 }, SN2: { reach: 150, engagementRate: 1.19 } }; function omitDeep(obj) { _.forIn(obj, function(value, key) { if (_.isObject(value)) { omitDeep(value); } else if (key === 'reach') { delete obj[key]; } }); } omitDeep(obj) console.log(obj); 

 <script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.15.0/lodash.min.js"></script> 

Answer 3

 _.mapValues(object, v => _.isObject(v)? _.omit(v, 'reach'): v) 

_.mapValues (object, [iteratee=_.identity])

Creates an object with the same keys as the object, and the values ​​generated by the start of each own enumerated property with the string keys of the object through iteratee . An iterator is called with three arguments: (value, key, object).

_.omit (object, [props])

creates an object consisting of its own and inherited enumerated string key properties of the object that are not omitted.

Answer 4

use _. mixin to extend omitDeep method:

 _.mixin({ 'omitDeep': function(obj, predicate) { return _.transform(obj, function(result, value, key) { if (_.isObject(value)) { value = _.omitDeep(value, predicate); } var doOmit = predicate(value, key); if (!doOmit) { _.isArray(obj) ? result.push(value) : result[key] = value; } }); } }); var my = { "key1": { "key2": { "key3": [null, { "key4": "string", "key5": true, "key6": null, "key7": 8, "key7": undefined }, null] } } }; console.log(my); console.log("omit null:", _.omitDeep(my, _.isNull)); console.log("omit undefined:", _.omitDeep(my, _.isUndefined)); 

 <script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.4/lodash.min.js"></script> 

Answer 5

Recursively omit keys from an object by defining an array of exclusive keys in ES6 + Typcript.

omitDeep(myObject, [omitKey1, omitKey2,...omitKeyN])

 // omitDeep.ts /** * Recursively remove keys from an object * @usage * * const input = { * id: 1, * __typename: '123', * createdAt: '1020209', * address: { * id: 1, * __typename: '123', * }, * variants: [ * 20, * { * id: 22, * title: 'hello world', * __typename: '123', * createdAt: '1020209', * variantOption: { * id: 1, * __typename: '123', * }, * }, * { * id: 32, * __typename: '123', * createdAt: '1020209', * }, * ], * } * * const output = { * id: 1, * address: { * id: 1, * }, * variants: [ * 20, * { * id: 22, * title: 'hello world', * variantOption: { * id: 1, * }, * }, * { * id: 32, * }, * ], * } * * expect(omitDeep(input, ['createdAt, 'updatedAt', __typename']).to.deep.equal(output) // true * * @param {object} input * @param {Array<number | string>>} excludes * @return {object} */ const omitDeep = (input: object, excludes: Array<number | string>): object => { return Object.entries(input).reduce((nextInput, [key, value]) => { const shouldExclude = excludes.includes(key) if (shouldExclude) return nextInput if (Array.isArray(value)) { const arrValue = value const nextValue = arrValue.map((arrItem) => { if (typeof arrItem === 'object') { return omitDeep(arrItem, excludes) } return arrItem }) nextInput[key] = nextValue return nextInput } else if (typeof value === 'object') { nextInput[key] = omitDeep(value, excludes) return nextInput } nextInput[key] = value return nextInput }, {}) } export default omitDeep