I have a method like this:
#RolesAllowed("ROLE_A")
#RequestMapping(value = "/",
method = RequestMethod.POST,
produces = MediaType.APPLICATION_JSON_VALUE)
public MRSData modifyMarketData(#RequestBody RequestObject body){
return repository.save(collection, body);
}
#Document
#Data
public class RequestObject {
#Id
#JsonInclude(JsonInclude.Include.NON_NULL)
private String _id;
private Object metadata;
private Object body;
}
Request looks like this:
{
"_id": "5f4ba6b3d93a8c1452f596a0",
"metadata": {
"data_type":"A"
}
}
Now only certain roles are allowed to access "data_type=A".
I want to use #RolesAllowed or equivalent to block the request based on #RequestBody
How should i achieve this?
Tx in advannce
If you want to filter based on request value, you can use #PreAuthorize.
Docs: https://docs.spring.io/spring-security/site/docs/current/reference/html5/#method-security-expressions
Some examples: https://www.baeldung.com/spring-security-method-security
Old answer:
You can use #PostAuthorize (or maybe #PostFilter) to restrict access based on the method's return value.
I want to ignore some fields during deserialization of json data in spring. I cannot use #JsonIgnore as the same model will be used in different methods and different fields need to be ignored.
I have tried to explain the situation with the below example.
class User
{
private String name;
private Integer id;
//getters and setters
}
This is the User class that will be used as model.
#RequestMapping(value = '/path1', method = RequestMethod.POST)
#ResponseBody
public ResponseEntity<CustomResponse> loadUser1(#RequestBody User user){
System.out.println(user.name);
//user.id is not required here
}
This is the first method that will use user.name and ignore user.id.
#RequestMapping(value = '/path2', method = RequestMethod.POST)
#ResponseBody
public ResponseEntity<CustomResponse> loadUser2(#RequestBody User user){
System.out.println(user.id);
//user.name is not required here
}
This is the second method that will use user.id and ignore user.name.
You can use #JsonFilter to achieve dynamic filtering.
First, create a filter using com.fasterxml.jackson.databind.ser.impl.SimpleBeanPropertyFilter and pass it to a filter provider com.fasterxml.jackson.databind.ser.impl.SimpleFilterProvider.
Then, declare this filter on your bean using #JsonFilter.
In your case, this will do it:
#JsonFilter("myFilter")
public class User {
private String name;
private int id;
// Getters and setters
}
This will apply the filter on your POJO:
public MappingJacksonValue getFiltered() {
SimpleFilterProvider filterProvider = new SimpleFilterProvider();
filterProvider.addFilter("myFilter", SimpleBeanPropertyFilter.filterOutAllExcept("id"));
User user = new User();
user.setId(1);
user.setName("Me");
MappingJacksonValue jacksonValue = new MappingJacksonValue(user);
jacksonValue.setFilters(filterProvider);
return jacksonValue;
}
Edit:
SimpleBeanPropertyFilter has factory methods to tender to almost all practical filtering scenarios. Use them appropriately.
I'm trying to distinguish between null values and not provided values when partially updating an entity with PUT request method in Spring Rest Controller.
Consider the following entity, as an example:
#Entity
private class Person {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
/* let's assume the following attributes may be null */
private String firstName;
private String lastName;
/* getters and setters ... */
}
My Person repository (Spring Data):
#Repository
public interface PersonRepository extends CrudRepository<Person, Long> {
}
The DTO I use:
private class PersonDTO {
private String firstName;
private String lastName;
/* getters and setters ... */
}
My Spring RestController:
#RestController
#RequestMapping("/api/people")
public class PersonController {
#Autowired
private PersonRepository people;
#Transactional
#RequestMapping(path = "/{personId}", method = RequestMethod.PUT)
public ResponseEntity<?> update(
#PathVariable String personId,
#RequestBody PersonDTO dto) {
// get the entity by ID
Person p = people.findOne(personId); // we assume it exists
// update ONLY entity attributes that have been defined
if(/* dto.getFirstName is defined */)
p.setFirstName = dto.getFirstName;
if(/* dto.getLastName is defined */)
p.setLastName = dto.getLastName;
return ResponseEntity.ok(p);
}
}
Request with missing property
{"firstName": "John"}
Expected behaviour: update firstName= "John" (leave lastName unchanged).
Request with null property
{"firstName": "John", "lastName": null}
Expected behaviour: update firstName="John" and set lastName=null.
I cannot distinguish between these two cases, sincelastName in the DTO is always set to null by Jackson.
Note:
I know that REST best practices (RFC 6902) recommend using PATCH instead of PUT for partial updates, but in my particular scenario I need to use PUT.
Another option is to use java.util.Optional.
import com.fasterxml.jackson.annotation.JsonInclude;
import java.util.Optional;
#JsonInclude(JsonInclude.Include.NON_NULL)
private class PersonDTO {
private Optional<String> firstName;
private Optional<String> lastName;
/* getters and setters ... */
}
If firstName is not set, the value is null, and would be ignored by the #JsonInclude annotation. Otherwise, if implicitly set in the request object, firstName would not be null, but firstName.get() would be. I found this browsing the solution #laffuste linked to a little lower down in a different comment (garretwilson's initial comment saying it didn't work turns out to work).
You can also map the DTO to the Entity with Jackson's ObjectMapper, and it will ignore properties that were not passed in the request object:
import com.fasterxml.jackson.databind.ObjectMapper;
class PersonController {
// ...
#Autowired
ObjectMapper objectMapper
#Transactional
#RequestMapping(path = "/{personId}", method = RequestMethod.PUT)
public ResponseEntity<?> update(
#PathVariable String personId,
#RequestBody PersonDTO dto
) {
Person p = people.findOne(personId);
objectMapper.updateValue(p, dto);
personRepository.save(p);
// return ...
}
}
Validating a DTO using java.util.Optional is a little different as well. It's documented here, but took me a while to find:
// ...
import javax.validation.constraints.NotNull;
import javax.validation.constraints.NotBlank;
import javax.validation.constraints.Pattern;
// ...
private class PersonDTO {
private Optional<#NotNull String> firstName;
private Optional<#NotBlank #Pattern(regexp = "...") String> lastName;
/* getters and setters ... */
}
In this case, firstName may not be set at all, but if set, may not be set to null if PersonDTO is validated.
//...
import javax.validation.Valid;
//...
public ResponseEntity<?> update(
#PathVariable String personId,
#RequestBody #Valid PersonDTO dto
) {
// ...
}
Also might be worth mentioning the use of Optional seems to be highly debated, and as of writing Lombok's maintainer(s) won't support it (see this question for example). This means using lombok.Data/lombok.Setter on a class with Optional fields with constraints doesn't work (it attempts to create setters with the constraints intact), so using #Setter/#Data causes an exception to be thrown as both the setter and the member variable have constraints set. It also seems better form to write the Setter without an Optional parameter, for example:
//...
import lombok.Getter;
//...
#Getter
private class PersonDTO {
private Optional<#NotNull String> firstName;
private Optional<#NotBlank #Pattern(regexp = "...") String> lastName;
public void setFirstName(String firstName) {
this.firstName = Optional.ofNullable(firstName);
}
// etc...
}
There is a better option, that does not involve changing your DTO's or to customize your setters.
It involves letting Jackson merge data with an existing data object, as follows:
MyData existingData = ...
ObjectReader readerForUpdating = objectMapper.readerForUpdating(existingData);
MyData mergedData = readerForUpdating.readValue(newData);
Any fields not present in newData will not overwrite data in existingData, but if a field is present it will be overwritten, even if it contains null.
Demo code:
ObjectMapper objectMapper = new ObjectMapper();
MyDTO dto = new MyDTO();
dto.setText("text");
dto.setAddress("address");
dto.setCity("city");
String json = "{\"text\": \"patched text\", \"city\": null}";
ObjectReader readerForUpdating = objectMapper.readerForUpdating(dto);
MyDTO merged = readerForUpdating.readValue(json);
Results in {"text": "patched text", "address": "address", "city": null}
Note that text and city were patched (city is now null) and that address was left alone.
In a Spring Rest Controller you will need to get the original JSON data instead of having Spring deserialize it in order to do this. So change your endpoint like this:
#Autowired ObjectMapper objectMapper;
#RequestMapping(path = "/{personId}", method = RequestMethod.PATCH)
public ResponseEntity<?> update(
#PathVariable String personId,
#RequestBody JsonNode jsonNode) {
RequestDTO existingData = getExistingDataFromSomewhere();
ObjectReader readerForUpdating = objectMapper.readerForUpdating(existingData);
RequestDTO mergedData = readerForUpdating.readValue(jsonNode);
...
}
Use boolean flags as jackson's author recommends.
class PersonDTO {
private String firstName;
private boolean isFirstNameDirty;
public void setFirstName(String firstName){
this.firstName = firstName;
this.isFirstNameDirty = true;
}
public String getFirstName() {
return firstName;
}
public boolean hasFirstName() {
return isFirstNameDirty;
}
}
Actually,if ignore the validation,you can solve your problem like this.
public class BusDto {
private Map<String, Object> changedAttrs = new HashMap<>();
/* getter and setter */
}
First, write a super class for your dto,like BusDto.
Second, change your dto to extend the super class, and change the
dto's set method,to put the attribute name and value to the
changedAttrs(beacause the spring would invoke the set when the
attribute has value no matter null or not null).
Third,traversal the map.
I have tried to solve the same problem. I found it quite easy to use JsonNode as the DTOs. This way you only get what is submitted.
You will need to write a MergeService yourself that does the actual work, similar to the BeanWrapper. I haven't found an existing framework that can do exactly what is needed. (If you use only Json requests you might be able to use Jacksons readForUpdate method.)
We actually use another node type as we need the same functionality from "standard form submits" and other service calls. Additionally the modifications should be applied within a transaction inside something called EntityService.
This MergeService will unfortunately become quite complex, as you will need to handle properties, lists, sets and maps yourself :)
The most problematic piece for me was to distinguish between changes within an element of a list/set and modifications or replacements of lists/sets.
And also validation will not be easy as you need to validate some properties against another model (the JPA entities in my case)
EDIT - Some mapping code (pseudo-code):
class SomeController {
#RequestMapping(value = { "/{id}" }, method = RequestMethod.POST, consumes = MediaType.APPLICATION_JSON_VALUE)
#ResponseBody
public void save(
#PathVariable("id") final Integer id,
#RequestBody final JsonNode modifications) {
modifierService.applyModifications(someEntityLoadedById, modifications);
}
}
class ModifierService {
public void applyModifications(Object updateObj, JsonNode node)
throws Exception {
BeanWrapperImpl bw = new BeanWrapperImpl(updateObj);
Iterator<String> fieldNames = node.fieldNames();
while (fieldNames.hasNext()) {
String fieldName = fieldNames.next();
Object valueToBeUpdated = node.get(fieldName);
Class<?> propertyType = bw.getPropertyType(fieldName);
if (propertyType == null) {
if (!ignoreUnkown) {
throw new IllegalArgumentException("Unkown field " + fieldName + " on type " + bw.getWrappedClass());
}
} else if (Map.class.isAssignableFrom(propertyType)) {
handleMap(bw, fieldName, valueToBeUpdated, ModificationType.MODIFY, createdObjects);
} else if (Collection.class.isAssignableFrom(propertyType)) {
handleCollection(bw, fieldName, valueToBeUpdated, ModificationType.MODIFY, createdObjects);
} else {
handleObject(bw, fieldName, valueToBeUpdated, propertyType, createdObjects);
}
}
}
}
Maybe too late for an answer, but you could:
By default, don't unset 'null' values. Provide an explicit list via query params what fields you want to unset. In such a way you can still send JSON that corresponds to your entity and have flexibility to unset fields when you need.
Depending on your use case, some endpoints may explicitly treat all null values as unset operations. A little bit dangerous for patching, but in some circumstances might be an option.
Another solution would be to imperatively deserialize the request body. By doing it, you will be able to collect user provided fields and selectively validate them.
So your DTO might look like this:
public class CatDto {
#NotBlank
private String name;
#Min(0)
#Max(100)
private int laziness;
#Max(3)
private int purringVolume;
}
And your controller can be something like this:
#RestController
#RequestMapping("/api/cats")
#io.swagger.v3.oas.annotations.parameters.RequestBody(
content = #Content(schema = #Schema(implementation = CatDto.class)))
// ^^ this passes your CatDto model to swagger (you must use springdoc to get it to work!)
public class CatController {
#Autowired
SmartValidator validator; // we'll use this to validate our request
#PatchMapping(path = "/{id}", consumes = "application/json")
public ResponseEntity<String> updateCat(
#PathVariable String id,
#RequestBody Map<String, Object> body
// ^^ no Valid annotation, no declarative DTO binding here!
) throws MethodArgumentNotValidException {
CatDto catDto = new CatDto();
WebDataBinder binder = new WebDataBinder(catDto);
BindingResult bindingResult = binder.getBindingResult();
List<String> patchFields = new ArrayList<>();
binder.bind(new MutablePropertyValues(body));
// ^^ imperatively bind to DTO
body.forEach((k, v) -> {
patchFields.add(k);
// ^^ collect user provided fields if you need
validator.validateValue(CatDto.class, k, v, bindingResult);
// ^^ imperatively validate user input
});
if (bindingResult.hasErrors()) {
throw new MethodArgumentNotValidException(null, bindingResult);
// ^^ this can be handled by your regular exception handler
}
// Here you can do normal stuff with your catDto.
// Map it to cat model, send to cat service, whatever.
return ResponseEntity.ok("cat updated");
}
}
No need for Optional's, no extra dependencies, your normal validation just works, your swagger looks good. The only problem is, you don't get proper merge patch on nested objects, but in many use cases that's not even required.
Probably to late but following code works for me to distinguish between null and not provided values
if(dto.getIban() == null){
log.info("Iban value is not provided");
}else if(dto.getIban().orElse(null) == null){
log.info("Iban is provided and has null value");
}else{
log.info("Iban value is : " + dto.getIban().get());
}
I am using #RequestParam to catch the front-end user input and pass it to the back end through controller and save it to the database.
So far controller handles the request like this:
#RequestMapping(value = "/myURL", method = RequestMethod.POST)
public String saveCustomer(
#RequestParam("customerFirstName") String customerFirstName,
#RequestParam("customerLastName") String customerLastName,) {
Customer customer = customerService.saveCustomer(
customerFirstName, customerLastName);
return null;
}
Well I guess this is fine when I only have two #RequestParam for two arguements, but I am facing some table that has more than 10 params, I think by using #RequestParam is apparently not realistic, is there another around this?
You can save the customer directly.
#RequestMapping(value = "/myURL", method = RequestMethod.POST)
public String saveCustomer(Customer customer) {
customerService.saveCustomer(customer);
return null;
}
Spring can databind POJOs as long as you have a no-args constructor and setters for your properties.
You should create a provider to use JSON, so you can send complex Java\JS objects and not just primitives.
If you are going to deal with multiple #RequestParam you can always opt for a bean class approach.
Controller:
#RequestMapping(value = "/myURL", method = RequestMethod.POST)
public String saveCustomer(
#RequestBody Customer customer) {
return null;
}
Bean:
public class Customer{
private String customerFirstName;
private String customerLastName;
//constructors, getters and setters
}
Check this link out for more info on #RequestBody
I am validating my form field with given piece of code.
//controller method
public String addBusiness(#Valid #ModelAttribute("myForm") MyForm myForm, ...)
{
//logic will go here.
}
//form
#Component
public class MyForm{
#Pattern(regexp = "[0-9]{3,10}", message = "should be valid number")
public String getZip_code()
{
return this.zip_code;
}
}
Now I want same validation on zip_code in another method of controller like,
#RequestMapping(value = "${validation.url}", method = RequestMethod.GET)
#ResponseBody
public List<String> getCityList(#RequestParam(value = "zip_code", required = true) final String zip_code)
{
//logic goes here
}
How is it possible?
It's not. #Valid doesn't apply to #RequestParam annotated parameters. You can create a custom HandlerMethodArgumentResolver to do this or do the validation yourself in the method.