获取请求主体为字符串/ JSON以使用JSON模式进行验证-Spring Boot REST API

Question

I'm trying to validate JSON (passed by a client as a request body) before it is converted into a model in Controller method.

If validation passes then return nothing, let the process continue as it was (spring boot to convert JSON into a model marked as @RequestBody). Throw error in case validation fails ( everit-org/json-schema ).

I tried to two way:

1. Implement HandlerMethodArgumentResolver , but resolveArgument() doesn't give request body details as it is already read and stored in ContentCachingRequestWrapper .

   NOTE: inputStream in ContentCachingRequestWrapper doesn't have any request body details.

2. Using spring Interceptor . But this doesn't help me to find request body type passed in the request. As JSON schema is different for each request.

Any other approaches I can try with?

Answer 1

I cannot add a comment ... so ...

What kind of validation do you need? If you only want to validate the fields like length of a string or range of a number and so on. I recommend you use @Validated on controller mehtod parameter, and model:

    @NotNull
    @Size(min = 32, max = 32)
    private String id;

controller:

@PatchMapping
public Object update(@RequestBody @Validated User user, Errors errors) {
    ...
}

If there is something wrong, errors.hasErrors() will return true .

edit:

OK, I did some tests, in a filter :

    HttpServletRequest httpServletRequest = (HttpServletRequest)request;
    ServletInputStream inputStream = httpServletRequest.getInputStream();
    byte[] a = new byte[1024];
    inputStream.read(a);
    System.out.println(IOUtils.toString(a));

I got a json string (a piece of request body) :

    {"template":"5AF78355A4F0D58E03CE9F55AFA850F8","bd":"" ...