Version: 2.10.20181129142450

Documentation (pdf)

More flexible document formats

So far Crnk followed the JSON API specification to the letter to establish a REST endpoint. The motivation of this was to have a clearly defined standard. In particular the relationship handling and inclusions allow to built powerful applications (such as when working with the redux pattern on the client side). However, at the same time this feature can make more simpler applications harder to write since they are forced to resolve those relationships. With crnk-format-plain-json a new module PlainJsonFormatModule is introduced that allows to setup alternative, custom document format next to JSON API. The ACCEPT and CONTENT-TYPE header will determine whether the JSON API or that custom format is used. An example can look like:
  "data" : {
    "id" : "12",
    "type" : "tasks",
    "name" : "someTask",
    "schedule" : {
      "data" : null,
      "links" : {
        "self" : "http://localhost:8080/tasks/12/relationships/schedule",
        "related" : "http://localhost:8080/tasks/12/schedule"
    "project" : {
      "data" : {
        "id" : "1",
        "type" : "projects",
        "name" : "someProject"
      "links" : {
        "self" : "http://localhost:8080/tasks/12/relationships/project",
        "related" : "http://localhost:8080/tasks/12/project"
Most notably the project relationship is directly inlined with the task. And a resource is written in a more flat manner without the attributes and relationships containers. Contributions to add more flexibility to the module are always welcome.

Improved default settings

To simplify development, two further flags have been enabled by default to simplify development. The flags have been disabled for historic reasons to maintain backward compatibility, but the longer the more they rather cause issues rather than help with compatibility. Both flags can be turned-off again if desired, but in general not recommended.

The first concerns `TypeParser.setEnforceJackson` that is enabled by default. It affects how filter parameters are serialized and deserialized to urls. Among others, it was by default searching for `parse` methods and constructors with a single String parameter. This behavior is no longer active. Instead always Jackson and its ObjectMapper is used for the mapping (as long as no custom StringMapper is installed with TypeParser). You may want to make use the following annotation to make custom value classes String-serializable:

	@JsonSerialize(using = ToStringSerializer.class)
In this case the toString method and String constructor is used by Jackson as well.

The second property concerns crnk.enforceIdName that is now enabled by default. This will result that all @JsonApiId-annotated fields are named "id" on the REST layer regardless of the name in Java. This matches the JSON API specification. It mainly affects the naming in sort and filter parameters.