'How to remove empty values from object using lodash
I have an object with several properties and I would like to remove objects/nested objects that are empty, using lodash. What is the best way to do this?
Let template = {
node: "test",
representation: {
range: { }
},
transmit: {
timeMs: 0
}
};
to
template = {
node: "test",
transmit: {
timeMs: 0
}
};
I tried something like this, but I am lost.
Utils.removeEmptyObjects = function(obj) {
return _.transform(obj, function(o, v, k) {
if (typeof v === 'object') {
o[k] = _.removeEmptyObjects(v);
} else if (!_.isEmpty(v)) {
o[k] = v;
}
});
};
_.mixin({
'removeEmptyObjects': Utils.removeEmptyObjects
});
Solution 1:[1]
You can achieve this through several steps:
Use pickBy() to pick object key-values, using the isObject() predicate.
Use mapValues() to recursively call
removeEmptyObjects(), note that it would only invoke this function with objects.Remove all empty objects that are found after the
mapValues()using omitBy() with an isEmpty() predicate.Assign all primitive values from the object all over again using assign() for assignment, and
omitBy()with anisObject()predicate.
function removeEmptyObjects(obj) {
return _(obj)
.pickBy(_.isObject) // pick objects only
.mapValues(removeEmptyObjects) // call only for object values
.omitBy(_.isEmpty) // remove all empty objects
.assign(_.omitBy(obj, _.isObject)) // assign back primitive values
.value();
}
function removeEmptyObjects(obj) {
return _(obj)
.pickBy(_.isObject)
.mapValues(removeEmptyObjects)
.omitBy(_.isEmpty)
.assign(_.omitBy(obj, _.isObject))
.value();
}
_.mixin({
removeEmptyObjects: removeEmptyObjects
});
var template = {
node: "test",
representation: {
range: {}
},
transmit: {
timeMs: 0
}
};
var result = _.removeEmptyObjects(template);
document.write('<pre>' + JSON.stringify(result, 0, 4) + '</pre>');<script src="https://cdn.jsdelivr.net/lodash/4.13.1/lodash.min.js"></script>Solution 2:[2]
To remove undefined, null, and empty string from an object with no nested objects
_.omitBy(object, (v) => _.isUndefined(v) || _.isNull(v) || v === '');
for nested objects, you can make a recursive function doing that
It will remove empty Objects, empty array, null, undefined, empty strings with any level...
removeEmpty(obj) {
let finalObj = {};
Object.keys(obj).forEach((key) => {
if (obj[key] && typeof obj[key] === 'object') {
const nestedObj = removeEmpty(obj[key]);
if (Object.keys(nestedObj).length) {
finalObj[key] = nestedObj;
}
} else if (obj[key] !== '' && obj[key] !== undefined && obj[key] !== null) {
finalObj[key] = obj[key];
}
});
return finalObj;
}
UPDATE 11-4-2022
Based on @RahulSoni comment I just fixed converting of arrays to objects. Now everything should be handled. Please let me know if you have any other comments
removeEmpty(obj) {
const finalObj = {};
Object.keys(obj).forEach((key) => {
if (obj[key] && typeof obj[key] === 'object' && !Array.isArray(obj[key])) {
const nestedObj = this.removeEmpty(obj[key]);
if (Object.keys(nestedObj).length) {
finalObj[key] = nestedObj;
}
} else if (Array.isArray(obj[key])) {
if (obj[key].length) {
obj[key].forEach((x) => {
const nestedObj = this.removeEmpty(x);
if (Object.keys(nestedObj).length) {
finalObj[key] = finalObj[key] ? [...finalObj[key], nestedObj] : [nestedObj];
}
});
}
} else if (obj[key] !== '' && obj[key] !== undefined && obj[key] !== null) {
finalObj[key] = obj[key];
}
});
return finalObj;
}
Example:
const obj = {
a: '',
aa: null,
aaa: undefined,
aaaa: 'aaaa',
aaaaa: 0,
aaaaaa: 1,
aaaaaaa: 2,
aaaaaaaa: true,
aaaaaaaaa: false,
emptyObj: {},
emptyArray: [],
array: [
{
a: '',
aa: null,
aaa: undefined,
aaaa: 'aaaa',
aaaaa: 0,
aaaaaa: 1,
aaaaaaa: 2,
aaaaaaaa: true,
aaaaaaaaa: false,
emptyObj: {},
emptyArray: [],
obj: {
a: '',
aa: null,
aaa: undefined,
aaaa: 'aaaa',
aaaaa: 0,
aaaaaa: 1,
aaaaaaa: 2,
aaaaaaaa: true,
aaaaaaaaa: false,
emptyObj: {},
emptyArray: [],
},
},
{
a: '',
aa: null,
aaa: undefined,
aaaa: 'aaaa',
aaaaa: 0,
aaaaaa: 1,
aaaaaaa: 2,
aaaaaaaa: true,
aaaaaaaaa: false,
emptyObj: {},
emptyArray: [],
obj: {
a: '',
aa: null,
aaa: undefined,
aaaa: 'aaaa',
aaaaa: 0,
aaaaaa: 1,
aaaaaaa: 2,
aaaaaaaa: true,
aaaaaaaaa: false,
emptyObj: {},
emptyArray: [],
},
},
],
b: {
a: '',
aa: null,
aaa: undefined,
aaaa: 'aaaa',
aaaaa: 0,
aaaaaa: 1,
aaaaaaa: 2,
aaaaaaaa: true,
aaaaaaaaa: false,
emptyObj: {},
emptyArray: [],
c: {
a: '',
aa: null,
aaa: undefined,
aaaa: 'aaaa',
aaaaa: 0,
aaaaaa: 1,
aaaaaaa: 2,
aaaaaaaa: true,
aaaaaaaaa: false,
emptyObj: {},
emptyArray: [],
},
},
};
const finalObj = removeEmpty(obj);
console.log('finalObj After remove', finalObj);
Solution 3:[3]
this one (typescript) also works with arrays and supports treeshaking:
import flow from "lodash/fp/flow";
import pickBy from "lodash/fp/pickBy";
import mapValues from "lodash/fp/mapValues";
import map from "lodash/fp/map";
import assign from "lodash/fp/assign";
import { default as fpOmitBy } from "lodash/fp/omitBy";
import { default as fpFilter } from "lodash/fp/filter";
import { isArray, isEmpty, isObject, omitBy } from "lodash-es";
export const compact = (obj) => !isObject(obj) ? obj : isArray(obj) ? compactArray(obj) : compactObject(obj);
const compactArray = (arr) => flow(
map(compact),
fpFilter(x => !isEmpty(x) || !isObject(x)),
)(arr)
const compactObject = (obj) => flow(
pickBy(isObject),
mapValues(compact),
fpOmitBy(isEmpty),
assign(omitBy(obj, isObject)),
)(obj);
Solution 4:[4]
I'm updating this for those who search for a solution to this problem in the future.
lodash provides an easier way to do this.
_.compact(arrayName) will remove all the empty/undefined/null values from an Array using lodash
Sources
This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.
Source: Stack Overflow
| Solution | Source |
|---|---|
| Solution 1 | |
| Solution 2 | |
| Solution 3 | c8z |
| Solution 4 |