The self
link is also used for embedded entities where it can be used to navigate to the proper entity. See this HAL example:
{
"_links": {
"self": { "href": "/orders" },
"curies": [{ "name": "ea", "href": "http://example.com/docs/rels/{rel}", "templated": true }],
"next": { "href": "/orders?page=2" },
"ea:find": {
"href": "/orders{?id}",
"templated": true
},
"ea:admin": [{
"href": "/admins/2",
"title": "Fred"
}, {
"href": "/admins/5",
"title": "Kate"
}]
},
"currentlyProcessing": 14,
"shippedToday": 20,
"_embedded": {
"ea:order": [{
"_links": {
"self": { "href": "/orders/123" },
"ea:basket": { "href": "/baskets/98712" },
"ea:customer": { "href": "/customers/7809" }
},
"total": 30.00,
"currency": "USD",
"status": "shipped"
}, {
"_links": {
"self": { "href": "/orders/124" },
"ea:basket": { "href": "/baskets/97213" },
"ea:customer": { "href": "/customers/12369" }
},
"total": 20.00,
"currency": "USD",
"status": "processing"
}]
}
}
The only rationale I could think of for having self links on top-level entities is that if you enter the service at some arbitrary entity, the self link gives you information about your context in the service. In the example above if somebody gave me a link to http://example.com/myservice/special/dev/2017/admins/2
, the self link relative to the service root (/admins/2
) would be useful for finding the root of the service and understanding that there are probably more admins, etc.