hal-serializer


A Node.js framework agnostic library for serializing your data to HAL compliant responses (a specification for building APIs in JSON).

Installation

``bash
npm install --save hal-serializer
`

Documentation

#### Register

`javascript
var HALSerializer = require('hal-serializer');
var Serializer = new HALSerializer();
Serializer.register(type, options);
`
Available options :

- blacklist (optional): An array of blacklisted attributes. Default = [].
- whitelist (optional): An array of whitelisted attributes. Default = [].
- links (optional): An object or a function that describes the links inside data. (If it is an object values can be string or function).
- topLevelMeta (optional): An object or a function that describes the links inside data. (If it is an object values can be string or function).
- topLevelLinks (optional): An object or a function that describes the links inside data. (If it is an object values can be string or function).
- embedded (optional): An object defining some embedded resources
- embedded: The property in data to use as an embedded resource
- type: The type to use for serializing the embedded resource (type need to be register)
- schema (optional): A custom schema for serializing the embedded resource. If no schema define, it use the default one.
- links (optional): An object or a function that describes the links for the relationship. (If it is an object values can be string or function).
- convertCase (optional): Case conversion for serializing data. Value can be : kebab-case, snake_case, camelCase

Usage

input data (can be a simple object or an array of objects)
`javascript
// Data
var data = {
id: "1",
title: "HAL Hypertext Application Language",
body: "The shortest article. Ever.",
created: "2015-05-22T14:56:29.000Z",
updated: "2015-05-22T14:56:28.000Z",
author: {
id: "1",
firstName: "Kaley",
lastName: "Maggio",
email: "Kaley-Maggio@example.com",
age: "80",
gender: "male"
},
tags: ["1", "2"],
photos: ["ed70cf44-9a34-4878-84e6-0c0e4a450cfe", "24ba3666-a593-498c-9f5d-55a4ee08c72e", "f386492d-df61-4573-b4e3-54f6f5d08acf"],
comments: [{
_id: "1",
body: "First !",
created: "2015-08-14T18:42:16.475Z"
}, {
_id: "2",
body: "I Like !",
created: "2015-09-14T18:42:12.475Z"
}, {
_id: "3",
body: "Awesome",
created: "2015-09-15T18:42:12.475Z"
}]
}
`

Register your resources types :
`javascript
var HALSerializer = require('hal-serializer');
var Serializer = new HALSerializer();

// Register 'article' type
Serializer.register('article', {
blacklist: ['updated'], // An array of blacklisted attributes. Default = []
links: function(data) { // An object or a function that describes links.
return {
self: {
href: '/articles/' + data.id
}
}
},
embedded: { // An object defining some embedded resources.
author: {
type: 'people', // The type of the embedded resource
links: function(data) {
return {
href: '/peoples/' + data.id
}
}
},
tags: {
type: 'tag'
},
photos: {
type: 'photo'
},
comments: {
type: 'comment',
schema: 'only-body' // A custom schema
}
},
topLevelMeta: function(extraOptions) { // An object or a function that describes top level meta.
return {
count: extraOptions.count
}
},
topLevelLinks: { // An object or a function that describes top level links.
self: {
href: '/articles'
}
}
});

// Register 'people' type
Serializer.register('people', {
links: {
self: function(data) {
return {
href: '/peoples/' + data.id
};
}
}
});

// Register 'tag' type
Serializer.register('tag', {});

// Register 'photo' type
Serializer.register('photo', {});

// Register 'comment' type with a custom schema
Serializer.register('comment', 'only-body', {
whitelist: ['body'],
});
`

Serialize it with the corresponding resource type, data and optional extra options :

`javascript
// Synchronously (blocking)
Serializer.serialize('article', data, {count: 2});

// Asynchronously (non-blocking)
Serializer.serializeAsync('article', data, {count: 2})
.then((result) => {
...
});
`

The output data will be :
`JSON
{
"_links": {
"self": {
"href": "/articles/1"
},
"author": {
"href": "/peoples/1"
}
},
"count": 2,
"id": "1",
"title": "HAL Hypertext Application Language",
"body": "The shortest article. Ever.",
"created": "2015-05-22T14:56:29.000Z",
"_embedded": {
"author": {
"_links": {
"self": {
"href": "/peoples/1"
}
},
"id": "1",
"firstName": "Kaley",
"lastName": "Maggio",
"email": "Kaley-Maggio@example.com",
"age": "80",
"gender": "male"
},
"comments": [
{
"body": "First !"
},
{
"body": "I Like !"
},
{
"body": "Awesome"
}
]
}
}
`

$3

input data (can be an simple object or an array of objects)

`javascript
var data = {
_links: {
self: {
href: '/articles/1'
},
author: {
href: '/peoples/1'
}
},
id: '1',
title: 'HAL Hypertext Application Language',
body: 'The shortest article. Ever.',
created: '2015-05-22T14:56:29.000Z',
_embedded: {
author: {
_links: {
self: {
href: '/peoples/1'
}
},
id: '1',
firstName: 'Kaley',
lastName: 'Maggio',
email: 'Kaley-Maggio@example.com',
age: '80',
gender: 'male'
}
}
};

Serializer.deserialize('article', data);
`

`JSON
{
"id": "1",
"title": "HAL Hypertext Application Language",
"body": "The shortest article. Ever.",
"created": "2015-05-22T14:56:29.000Z",
"author": {
"id": "1",
"firstName": "Kaley",
"lastName": "Maggio",
"email": "Kaley-Maggio@example.com",
"age": "80",
"gender": "male"
}
}
`

Custom schemas

It is possible to define multiple custom schemas for a resource type :

`javascript
Serializer.register(type, 'customSchema', options);
`

If you want to apply this schema on the primary data :

`javascript
Serializer.serialize('article', data, 'customSchema', {count: 2});
`

Or if you want to apply this schema on a embedded resource, define this schema on embedded resource options with the key schema :

Example :
`javascript
embedded: {
comments: {
type: 'comment'
schema: 'customSchema'
}
}
``

Requirements

hal-serializer use ECMAScript 2015 (ES6) features supported natively by Node.js 4 and above (ECMAScript 2015 (ES6) | Node.js). Make sure that you have Node.js 4+ or above.

License

MIT