从HttpServletResponse的返回HAL JSON

Question

我想在“UsernamePasswordAuthenticationFilter”我“successfullAuthentication”方法使用HATEOAS返回响应体，但返回以这种格式的链接：

"links": [
    {
        "rel": "self",
        "href": "http://localhost:8080/api/users/5c55ee26911e9f04acb77c91",
        "hreflang": null,
        "media": null,
        "title": null,
        "type": null,
        "deprecation": null
    },

我想它返回HAL JSON格式因此它看起来像这样：

"_links": {
    "self": {
        "href": "http://localhost:8080/api/users/5c55ee26911e9f04acb77c91"
    },

我有这个在我的方法（反应是HttpServletResponse的）：

User user = userService.findById(authResult.getName());
String json = Jackson.toJsonString(userResourceAssembler.toResource(user));
response.setContentType("application/hal+json");
response.setCharacterEncoding("UTF-8");
response.addHeader(jwtConfig.getHeader(), jwtConfig.getPrefix() + token);
response.getWriter().write(json);

我也有这个在我的WebConfig：@EnableHypermediaSupport（类型= {} EnableHypermediaSupport.HypermediaType.HAL）

有谁知道为什么发生这种情况？

Answer 1

我发现在这个问题GitHub的答案：https://github.com/spring-projects/spring-hateoas/issues/270#issuecomment-145606558

基本上：

private String convertToHalString(ResourceSupport resource) {
    ObjectMapper mapper = new ObjectMapper();
    mapper.registerModule(new Jackson2HalModule());
    mapper.setHandlerInstantiator(new Jackson2HalModule.HalHandlerInstantiator(
            new EvoInflectorRelProvider(), null, null));
    String resourceString = null;
    try {
        resourceString = mapper.writeValueAsString(resource);
    } catch (JsonProcessingException e) {
        e.printStackTrace();
    }
    return resourceString;
}

Answer 2

尽量延长所有的模型类 - 添加HATEOAS链接 -

与org.springframework.hateoas.ResourceSupport class

假设你有相应的URI在控制器类

Link link = ControllerLinkBuilder
           .linkTo(UserController.class)
           .slash(user.getXXX())
           .withSelfRel();

//for single resource
user.add(link);

Link userLink = ControllerLinkBuilder
            .linkTo(ControllerLinkBuilder
            .methodOn(UserController.class).getAllUsers())
            .withSelfRel();

//For collections
userList.add(userLink);

参考：https://spring.io/understanding/HATEOAS