The core functionality of Spring Data REST is to export resources for Spring Data repositories. Thus, the core artifact to look at and potentially tweak to customize the way the exporting works is the repository interface. Assume the following repository interface: public interface OrderRepository extends CrudRepository<Order, Long> { } For this repository, Spring Data REST exposes a collection resource at /orders. The path is derived from the uncapitalized, pluralized, simple class name of the domain class being managed. It also exposes a an item resource for each of the items managed by te repository under the URI template /orders/{id}. By default the HTTP methods to interact with these resources map to the according methods of CrudRepository. Read more on that in the sections on collection resources and item resources.

For the resources exposed, we use a set of default status codes: 200 OK - for plain GET requests. 201 Created - for POST and PUT requests that create new resources. 204 No Content - for PUT, PATCH, and DELETE requests if the configuration is set to not return response bodies for resource updates (RepositoryRestConfiguration.returnBodyOnUpdate). If the configuration value is set to include responses for PUT, 200 OK will be returned for updates, 201 Created will be returned for resource created through PUT.

A core principle of HATEOAS is that resources should be discoverable through the publication of links that point to the available resources. There are a few competing de-facto standards of how to represent links in JSON. By default, Spring Data REST uses HAL to render responses. HAL defines links to be contained in a _link property of the returned document. Resource discovery starts at the top level of the application. By issuing a request to the root URL under which the Spring Data REST application is deployed, the client can extract a set of links from the returned JSON object that represent the next level of resources that are available to the client. For example, to discover what resources are available at the root of the application, issue an HTTP GET to the root URL: curl -v http://localhost:8080/ < HTTP/1.1 200 OK < Content-Type: application/hal+json { "_links" : { "orders" : { "href" : "http://localhost:8080/orders" } } } The _links property of the result document is an object in itself consisting of keys representing the relation type with nested link objects as specified in HAL.

Spring Data REST exposes a collection resource named after the uncapitalized, pluralized version of the domain class the exported repository is handling. Both the name of the resource and the path can be customized using the @RepositoryRestResource on the repository interface.

Collections resources support both GET and POST. All other HTTP methods will cause a 405 Method Not Allowed.

Returns all entities the repository servers through its findAll(…) method. If the repository is a paging repository we include the pagination links if necessary and additional page metadata. If the repository has pagination capabilities the resource takes the following parameters: page - the page number to access (0 indexed, defaults to 0). size - the page size requested (defaults to 20). sort - a collection of sort directives in the format ($propertyname,)+[asc|desc]?. 405 Method Not Allowed - if the findAll(…) methods was not exported (through @RestResource(exported = false)) or is not present in the repository at all. application/hal+json application/json search - a search resource if the backing repository exposes query methods.

Creates a new entity from the given request body. 405 Method Not Allowed - if the save(…) methods was not exported (through @RestResource(exported = false)) or is not present in the repository at all. application/hal+json application/json

Spring Data REST exposes a resource for individual collection items as sub-resources of the collection resource.

Item resources generally support GET, PUT, PATCH and DELETE unless explicit configuration prevents that (see below for details).

Returns a single entity. 405 Method Not Allowed - if the findOne(…) methods was not exported (through @RestResource(exported = false)) or is not present in the repository at all. application/hal+json application/json For every association of the domain type we expose links named after the association property. This can be customized by using @RestResource on the property. The related resources are of type association resource.

Replaces the state of the target resource with the supplied request body. 405 Method Not Allowed - if the save(…) methods was not exported (through @RestResource(exported = false)) or is not present in the repository at all. application/hal+json application/json

Similar to PUT but only applying values sent with the request body. 405 Method Not Allowed - if the save(…) methods was not exported (through @RestResource(exported = false)) or is not present in the repository at all. application/hal+json application/json

Deletes the resource exposed. 405 Method Not Allowed - if the delete(…) methods was not exported (through @RestResource(exported = false)) or is not present in the repository at all.

Spring Data REST exposes sub-resources of every item resource for each of the associations the item resource has. The name and path of the of the resource defaults to the name of the association property and can be customized using @RestResource on the association property.

Reutrns the state of the association resource application/hal+json application/json

Binds the resource pointed to by the given URI(s) to the resource. This 400 Bad Request - if multiple URIs were given for a to-one-association. text/uri-list - URIs pointing to the resource to bind to the association.

Only supported for collection associations. Adds a new element to the collection. text/uri-list - URIs pointing to the resource to add to the association.

Unbinds the association. 405 Method Not Allowed - if the association is non-optional.

The search resource returns links for all query methods exposed by a repository. The path and name of the query method resources can be modified using @RestResource on the method declaration.

As the search resource is a read-only resource it supports GET only.

Returns a list of links pointing to the individual query method resources application/hal+json application/json For every query method declared in the repository we expose a query method resource. If the resource supports pagination, the URI pointing to it will be a URI template containing the pagination parameters.

The query method resource executes the query exposed through an individual query method on the repository interface.

As the search resource is a read-only resource it supports GET only.

Returns the result of the query execution. If the query method has pagination capabilities (indicated in the URI template pointing to the resource) the resource takes the following parameters: page - the page number to access (0 indexed, defaults to 0). size - the page size requested (defaults to 20). sort - a collection of sort directives in the format ($propertyname,)+[asc|desc]?. application/hal+json application/json