Recommendations

This section contains recommendations for JSON API implementations. These recommendations are intended to establish a level of consistency in areas that are beyond the scope of the base JSON API specification.

Recommendations for Naming

It is recommended that resource types, attribute names, and association names be "dasherized"; i.e. consist of only lower case alphanumeric characters and dashes (U+002D HYPHEN-MINUS, "-").

It is also recommended that resource types be pluralized. Dasherized and pluralized resource types can be used as URL segments without translation, as discussed below.

Recommendations for URL Design

Reference Document

When determining an API's URL structure, it is helpful to consider that all of its resources exist in a single "reference document" in which each resource is addressable at a unique path. Resources are grouped by type at the top level of this document. Individual resources are keyed by ID within these typed collections. Attributes and links within individual resources are uniquely addressable according to the resource object structure described above.

This concept of a reference document is used to determine appropriate URLs for resources as well as their relationships. It is important to understand that this reference document differs slightly in structure from documents used to transport resources due to different goals and constraints. For instance, collections in the reference document are represented as sets because members must be addressable by ID, while collections are represented as arrays in transport documents because order is significant.

URLs for Resource Collections

It is recommended that the URL for a collection of resources be formed from the resource type.

For example, a collection of resources of type "photos" will have the URL:

/photos

URLs for Individual Resources

Treat collections of resources as sets keyed by resource ID. The URL for an individual resource can be formed by appending the resource's ID to the collection URL.

For example, a photo with an ID of "1" will have the URL:

/photos/1

Relationship URLs and Related Resource URLs

As described in the base specification, there are two URLs that can be exposed for each relationship:

• the "relationship URL" - a URL for the relationship itself, which is identified with the "self" key in a link object. This URL allows the client to directly manipulate the relationship. For example, it would allow a client to remove an author from a post without deleting the people resource itself.

• the "related resource URL" - a URL for the related resource(s), which is identified with the "related" key within a link object. When fetched, it returns the related resource object(s) as the response's primary data.

It is recommended that a relationship URL be formed by appending /links/ and the name of the relationship to the resource's URL.

For example, a photo's comments relationship will have the URL:

/photos/1/links/comments

And a photo's photographer relationship will have the URL:

/photos/1/links/photographer

It is recommended that a related resource URL be formed by appending the name of the relationship to the resource's URL.

For example, the URL for a photo's comments will be:

/photos/1/comments

And the URL for a photo's photographer will be:

/photos/1/photographer

Because these URLs represent resources in relationships, they should not be used as self links for the resources themselves. Instead the recommendations for individual resource URLs should still apply when forming self links.

Recommendations for Filtering

The base specification is agnostic about filtering strategies supported by a server. The filter query parameter is reserved to be used as the basis for any filtering strategy.

It's recommended that servers that wish to support filtering of a resource collection based upon associations do so by allowing query parameters that combine filter with the association name.

For example, the following is a request for all comments associated with a particular post:

GET /comments?filter[post]=1

Multiple filter values can be combined in a comma-separated list. For example:

GET /comments?filter[post]=1,2

Furthermore, multiple filters can be applied to a single request:

GET /comments?filter[post]=1,2&filter[author]=12