humps

What is humps?

The 'humps' npm package is a utility library for converting object keys between different naming conventions, such as camelCase, snake_case, and kebab-case. It is particularly useful for working with APIs that use different naming conventions than your JavaScript code.

What are humps's main functionalities?

camelizeKeys

Converts the keys of an object from snake_case to camelCase.

const humps = require('humps');
const input = { first_name: 'John', last_name: 'Doe' };
const output = humps.camelizeKeys(input);
console.log(output); // { firstName: 'John', lastName: 'Doe' }

decamelizeKeys

Converts the keys of an object from camelCase to snake_case.

const humps = require('humps');
const input = { firstName: 'John', lastName: 'Doe' };
const output = humps.decamelizeKeys(input);
console.log(output); // { first_name: 'John', last_name: 'Doe' }

kebabizeKeys

Converts the keys of an object from camelCase to kebab-case.

const humps = require('humps');
const input = { firstName: 'John', lastName: 'Doe' };
const output = humps.kebabizeKeys(input);
console.log(output); // { 'first-name': 'John', 'last-name': 'Doe' }

pascalizeKeys

Converts the keys of an object from snake_case to PascalCase.

const humps = require('humps');
const input = { first_name: 'John', last_name: 'Doe' };
const output = humps.pascalizeKeys(input);
console.log(output); // { FirstName: 'John', LastName: 'Doe' }

Other packages similar to humps

lodash

Lodash is a popular utility library that provides a wide range of functions for manipulating arrays, objects, and other data types. It includes methods for converting object keys between different naming conventions, similar to humps, but offers a much broader set of utilities.

change-case

The 'change-case' package provides a collection of functions for converting strings between different cases, such as camelCase, snake_case, and kebab-case. While it focuses on string manipulation rather than object keys, it can be used in conjunction with other libraries to achieve similar functionality to humps.

case-converter

The 'case-converter' package is a lightweight library specifically designed for converting object keys between different naming conventions. It offers similar functionality to humps but with a smaller footprint and fewer dependencies.

README

humps

Underscore-to-camelCase converter (and vice versa) for strings and object keys in JavaScript.

When converting object keys, it will walk the structure, converting any nested objects (or arrays of nested objects) along the way. Handy for converting JSON between JavaScript and Ruby/Rails APIs.

Takes inspiration from Ember Data and copies some utility functions from Underscore.js.

Usage

Converting strings

humps.camelize('hello_world') // 'helloWorld'
humps.decamelize('fooBar') // 'foo_bar'
humps.decamelize('fooBarBaz', { separator: '-' }) // 'foo-bar-baz'

Converting object keys

var object = { attr_one: 'foo', attr_two: 'bar' }
humps.camelizeKeys(object); // { attrOne: 'foo', attrTwo: 'bar' }

Arrays of objects are also converted

var array = [{ attr_one: 'foo' }, { attr_one: 'bar' }]
humps.camelizeKeys(array); // [{ attrOne: 'foo' }, { attrOne: 'bar' }]

It also accepts a callback which can modify the conversion behavior. For example to prevent conversion of keys containing only uppercase letters or numbers:

humps.camelizeKeys(obj, function (key, convert) {
  return /^[A-Z0-9_]+$/.test(key) ? key : convert(key);
});
humps.decamelizeKeys(obj, function (key, convert, options) {
  return /^[A-Z0-9_]+$/.test(key) ? key : convert(key, options);
});

In order to use the callback with options use the process option:

humps.decamelizeKeys(obj, {
    separator: '-',
    process: function (key, convert, options) {
      return /^[A-Z0-9_]+$/.test(key) ? key : convert(key, options);
    }
});

API

humps.camelize(string)

Removes any hypens, underscores, and whitespace characters, and uppercases the first character that follows.

humps.camelize('hello_world-foo bar') // 'helloWorldFooBar'

humps.pascalize(string)

Similar to humps.camelize(string), but also ensures that the first character is uppercase.

humps.pascalize('hello_world-foo bar') // 'HelloWorldFooBar'

humps.decamelize(string, options)

Converts camelCased string to an underscore-separated string.

humps.decamelize('helloWorldFooBar') // 'hello_world_foo_bar'

The separator can be customized with the separator option.

humps.decamelize('helloWorldFooBar', { separator: '-' }) // 'hello-world-foo-bar'

By default, decamelize will only split words on capital letters (not numbers as in humps pre v1.0). To customize this behaviour, use the split option. This should be a regular expression which, when passed into String.prototype.split, produces an array of words (by default the regular expression is: /(?=[A-Z])/). For example, to treat numbers as uppercase:

humps.decamelize('helloWorld1', { split: /(?=[A-Z0-9])/ }) // 'hello_world_1'

humps.depascalize(string, options)

Same as humps.decamelize above.

humps.camelizeKeys(object, options)

Converts object keys to camelCase. It also converts arrays of objects.

humps.pascalizeKeys(object, options)

Converts object keys to PascalCase. It also converts arrays of objects.

humps.decamelizeKeys(object, options)

Separates camelCased object keys with an underscore. It also converts arrays of objects. See humps.decamelize for details of options.

humps.depascalizeKeys(object, options)

See humps.decamelizeKeys.

Licence

humps is copyright © 2012+ Dom Christie and released under the MIT license.