Make collection propertie render as relation instead of property in json HAL representaion

Question

I got hal formatted response as this:

{
  \"name\": \"Publisher A\",
  \"bookPublishers\": [
    {
      \"publishedDate\": \"2019-07-12T08:19:04.583+0000\",         


        

Answer 1

For collection relationships, Spring Data will provide a link when a repository exists for the relevant type. Where no repository exists then the collection will be in-lined in the response, otherwise, how else will the client get the data.

Therefore, create a repository for your BookPublisher type.

Relevant documentation part citation:

the component responsible for creating the links to referenced entities (such as those objects under the _links property in the object’s JSON representation). It takes an @Entity and iterates over its properties, creating links for those properties that are managed by a Repository and copying across any embedded or simple properties.

You can also create a projection that would in-line the data when required. Clients could specify this projection in the request therefore preventing an additional server call.

e.g.

/publisher/1?projection=withBookPublishers.

https://docs.spring.io/spring-data/rest/docs/current/reference/html/#projections-excerpts.projections