halson

HALSON

The HAL+JSON Resource Object.

Installation

node.js

npm install halson --save

Bower

bower install halson --save

Example

var halson = require('halson');

var embed = halson({
        title: "joyent / node",
        description: "evented I/O for v8 javascript"
    })
    .addLink('self', '/joyent/node')
    .addLink('author', {
        href: '/joyent',
        title: 'Joyent'
    });

var resource = halson({
        title: "Juraj Hájovský",
        username: "hajovsky",
        emails: [
            "[e-mail]",
            "[e-mail]"
        ]
    })
    .addLink('self', '/hajovsky')
    .addEmbed('starred', embed);

console.log(resource.title);
console.log(resource.emails[0]);
console.log(resource.getLink('self'));
console.log(resource.getEmbed('starred'));
console.log(JSON.stringify(resource));

API

halson([data])

Create a new HAL+JSON Resource Object.

• data (optional): Initial data as serialized string or Object.

// empty HAL+JSON Resource Object
var resource = halson();

// resource from a serialized data
var resource = halson('{title:"Lorem Ipsum",_links:{self:{href:"/ipsum"}}');

// resource from an Object
resource = halson({
    _links: {
        self: {
            href: {"/ipsum"}
        }
    },
    title: "Lorem Ipsum"
});

// resource from another resource (no-op)
var resourceX = halson(resource);
console.log(resource === resourceX); // true

HALSONResource#listLinkRels()

List all link relations.

var data = {
    _links: {
        self: {href: '/hajovsky'},
        related: [
            {href: 'http://hajovsky.sk'},
            {href: 'https://twitter.com/hajovsky'}
        ]
    }
}

var resource = halson(data);
console.log(resource.listLinkRels()); // ['self', 'related']

HALSONResource#listEmbedRels()

List all link relations.

var data = {
    _embedded: {
        starred: {
            _links: {
                self: {href: '/joyent/node'}
            }
            title: "joyent / node",
            description: "evented I/O for v8 javascript"
        }
    }
}

var resource = halson(data);
console.log(resource.listEmbedRels()); // ['starred']

HALSONResource#getLinks(rel, [filterCallback, [begin, [end]]])

Get all links with relation rel.

• rel (required): Relation name.
• filterCallback (optional): Function used to filter array of links. doc
• begin, end (optional): slice filtered links. doc

var twitterLinks = resource.getLinks('related', function(item) {
    return item.name === "twitter";
});

HALSONResource#getLink(rel, [filterCallback, [default]])

Get first link with relation rel.

• rel (required): Relation name.
• filterCallback (optional): Function used to filter array of links. doc
• default (optional): Default value if the link does not exist.

var firstRelatedLink = resource.getLink('related');

HALSONResource#getEmbeds(rel, [filterCallback, [begin, [end]]])

Get all embedded resources with relation rel.

• rel (required): Relation name.
• filterCallback (optional): Function used to filter array of embeds. doc
• begin, end (optional): slice filtered links. doc

var embeds = resource.getEmbeds('starred');

HALSONResource#getEmbed(rel, [filterCallback, [default]])

Get first embedded resource with relation rel.

• rel (required): Relation name.
• filterCallback (optional): Function used to filter array of embeds. doc
• default (optional): Default value if the link does not exist.

var nodeProject = resource.getEmbed('starred', function(embed) {
    return embed.getLink('self', {}).href === '/joyent/node';
});

HALSONResource#addLink(rel, link)

Add a link with relation rel.

• rel (required): Relation name.
• link (required): Link to be added (string or Object).

resource
    .addLink('related', 'http://hajovsky.sk')
    .addLink('related', {
        href: 'https://twitter.com/hajovsky',
        name: 'twitter'
    });

HALSONResource#addEmbed(rel, embed)

Add a nested resource with relation rel.

• rel (required): Relation name.
• embed (required): Resource to be embedded (Object or HALSONResource).

var embed = {
    _links: {
        self: {href: '/joyent/node'}
    },
    title: "joyent / node"
}
resource.addEmbed('starred', embed);

HALSONResource#insertEmbed(rel, index, embed)

Add a nested resource with relation rel.

• rel (required): Relation name.
• index (required): Index number where embed will be inserted
• embed (required): Resource to be embedded (Object or HALSONResource).

var embed = {
    _links: {
        self: {href: '/joyent/node'}
    },
    title: "joyent / node"
};
resource.addEmbed('starred', embed); // add embed

var embed2 = {
    _links: {
        self: {href: '/joyent/node'}
    },
    title: "joyent / node"
};
resource.insertEmbed('starred', 0, embed2); // insert new embed before first item

HALSONResource#removeLinks(rel, [filterCallback])

Remove links with relation rel. If filterCallback is not defined, all links with relation rel will be removed.

• rel (required): Relation name.
• filterCallback (optional): Function used to filter array of links. doc

// remove links with relation 'related' and name 'twitter'
resource.removeLinks('related', function(link) {
    return link.name === "twitter";
});

HALSONResource#removeEmbeds(rel, [filterCallback])

Remove embedded resources with relation rel. If filterCallback is not defined, all embeds with relation rel will be removed.

• rel (required): Relation name.
• filterCallback (optional): Function used to filter array of links. doc

// remove embedded resources with relation 'starred' and self-link '/koajs/koa'
resource.removeLinks('starred', function(embed) {
    return embed.getLink('self', {}).href === '/koajs/koa';
});

Changelog

Release 2.3.0 (2015-01-11)

• Altered addEmbed to accept an array as a second argument