#JsonView with Spring PagedResources - java

I've a pojo exposed with Rest Controller. I need to hide some properties for one GET request, so I decided to use jackson's annotation #JsonView. I can't find any way to made it with #JsonView and PagedResources.
Here is my pojo :
public class Pojo {
interface RestrictedPojo {}
interface AllPojo extends RestrictedPojo {}
#Id
#JsonView(RestrictedPojo.class)
private String identifier;
#JsonView(AllPojo.class)
private String someproperty;
/**
* Property I want to hide
*/
#JsonView(RestrictedPojo.class)
private String someHiddenProperty;
}
Here is my Controller :
#RepositoryRestController
#RequestMapping(value = "/pojo")
#RequiredArgsConstructor(onConstructor = #__(#Autowired))
public class PojoController {
private final PojoService pojoService;
private final IdentityUtils identityUtils;
private final PagedResourcesAssembler<Pojo> pagedResourcesAssembler;
#PreAuthorize("hasRole('SOME_ROLE')")
#GetMapping
#JsonView(Pojo.RestrictedPojo.class)
public ResponseEntity<PagedResources<Resource<Pojo>>> getAllRestrictedPojos(final Pageable pageable) {
final Page<Pojo> allPojo = pojoService.getAllRestrictedPojos(pageable);
final PagedResources<Resource<Pojo>> resources = pagedResourcesAssembler.toResource(allPojo );
return ResponseEntity.ok(resources);
}
#PreAuthorize("hasRole('SOME_ROLE')")
#GetMapping
#JsonView(Pojo.AllPojo.class)
public ResponseEntity<PagedResources<Resource<Pojo>>> getAllPojos(final Pageable pageable) {
final Page<Pojo> allPojo = pojoService.getAllRestrictedPojos(pageable);
final PagedResources<Resource<Pojo>> resources = pagedResourcesAssembler.toResource(allPojo );
return ResponseEntity.ok(resources);
}
}
I didn't wrote specific config, it's a basic spring boot app.
Can anyone help ?
Thanks

Related

Problem with status 415 in Spring MockMVC Tests after trying to send a REST Post Request

I have a REST POST endpoint which is used to create an entity. I've trying to test it with MockMVC but every time that i sent the request i received a 415 status code (media not supported):
java.lang.AssertionError: Status expected:<201> but was:<415> Expected :201 Actual :415
The endpoint accepts json body in the request and I sent this data using the MockMVC contentType as APPLICATION_JSON_VALUE and the content method with the serialized object by Jackson.
The controller ALSO is managed my Spring Security Filters but i think this is not the problem as i'm using the #AutoConfigureMockMvc(addFilters = false) and the HTTP status code is related to not supported media type and not about any security exception.
I've found a plenty of topics talking about it but none was able to solve my problem. One of the cases was including the #EnableWebMvc into the Controller OR as a configuration bean test, but none work it.
My attempt with #EnableWebMvc as test bean
#TestConfiguration
#EnableWebMvc
public class ProdutoControllerConfigurationTest {
#Bean
public ProdutoController produtoController() {
return new ProdutoController(/* dependencies by autowired */);
}
}
EDIT: I also tried with different MediaType like MediaType.APPLICATION_JSON and MediaType.APPLICATION_JSON_VALUE
My DTO class
public class CriarProdutoDTO {
#NotNull
#Size(min = 2)
#JsonProperty("nome_produto")
private final String nomeProduto;
#DecimalMin("0.1")
private final BigDecimal preco;
private final String descricao;
#NotNull
#Min(0)
#JsonProperty("quantidade_estoque")
private final Integer quantidadeEstoque;
#NotNull
#Min(1)
#JsonProperty("categoria_id")
private final Integer categoriaId;
public CriarProdutoDTO(String nomeProduto, BigDecimal preco, String descricao, Integer quantidadeEstoque, Integer categoriaId) {
this.nomeProduto = nomeProduto;
this.preco = preco;
this.descricao = descricao;
this.quantidadeEstoque = quantidadeEstoque;
this.categoriaId = categoriaId;
}
}
My current tests:
#ActiveProfiles("testes")
#ExtendWith(SpringExtension.class)
#SpringBootTest
#WebAppConfiguration
#AutoConfigureMockMvc(addFilters = false)
#AutoConfigureTestDatabase(replace = AutoConfigureTestDatabase.Replace.ANY)
public class ProdutoControllerTest {
#Autowired
private MockMvc mockMvc;
#Autowired
private ObjectMapper objectMapper;
#Test
public void deveRetornarCreated_criacaoProdutoSucesso() throws Exception {
CriarProdutoDTO criarProdutoDTO = new CriarProdutoDTO("Nome", new BigDecimal("2.0"), "DESCRIÇÃO", 2, 1);
mockMvc.perform(MockMvcRequestBuilders.post("/api/produtos")
.contentType(MediaType.APPLICATION_JSON_VALUE)
.content(objectMapper.writeValueAsString(criarProdutoDTO)))
.andDo(MockMvcResultHandlers.print())
.andExpect(MockMvcResultMatchers.status().isCreated());
}
}
My Controller:
#RestController
#RequestMapping(value = "/api/produtos")
public class ProdutoController {
#Autowired
private ProdutoService produtoService;
#Autowired
private CriarProdutoDtoToProdutoConverter produtoConverter;
#PostMapping
#ResponseStatus(HttpStatus.CREATED)
public void cadastrar(#RequestBody #Valid CriarProdutoDTO produtoDTO) {
Produto novoProduto = produtoConverter.converter(produtoDTO);
produtoService.cadastrar(novoProduto);
}
}
try add Accept header to your request
Accept=application/json
I found out the problem.
The problem was occurring in Jackson's Serialization from my Data Transfer Object (DTO)
My DTO has an args-constructor and because of that i have to use the #JsonCreator to point the args constructor. What i didn't expect was that you must annotate all the constructor parameters with #JsonProperty as Jackson didn't know the exact order to instantiate the object from the construtor, that was my problem.
Another way is creating a bean for that, so you don't have to use the #JsonCreator
The solution:
#JsonCreator
public CriarProdutoDTO(
#JsonProperty("nome_produto") String nomeProduto, #JsonProperty("preco") BigDecimal preco,
#JsonProperty("descricao") String descricao, #JsonProperty("quantidade_estoque") Integer quantidadeEstoque,
#JsonProperty("categoria_id") Integer categoriaId) {
this.nomeProduto = nomeProduto;
this.preco = preco;
this.descricao = descricao;
this.quantidadeEstoque = quantidadeEstoque;
this.categoriaId = categoriaId;
}

Not Able to Successfully USE Validations in Spring REST Webservice

I am trying to apply validations on my SPRING REST-API but i am getting this exception:
Apr 10, 2020 12:05:26 PM org.springframework.web.servlet.mvc.method.annotation.ExceptionHandlerExceptionResolver doResolveHandlerMethodExceptionWARNING: Failed to invoke #ExceptionHandler method: public com.luv2code.springdemo.exceptionhandling.RestFieldErrorValidation com.luv2code.springdemo.exceptionhandling.GlobalExceptionHandler.processValidationError(org.springframework.web.bind.MethodArgumentNotValidException)org.springframework.http.converter.HttpMessageNotWritableException: No converter found for return value of type: class com.luv2code.springdemo.exceptionhandling.RestFieldErrorValidation at org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodProcessor.writeWithMessageConverters(AbstractMessageConverterMethodProcessor.java:226)
Entity Class:
#Entity#Table(name="customer")
public class Customer {
#Id
#GeneratedValue(strategy=GenerationType.IDENTITY)
#Column(name="id")
private int id;
#Column(name="first_name")
#NotNull(message = "Firstname is necessary")
#Size(min=1,message="This field is required")
private String firstName;
#Column(name="last_name")
#NotNull(message = "Lastname is necessary")
#Size(min=1,message="This field is required")
private String lastName;
#Column(name="email")
private String email;
// getters and setters
}
FieldValidation Handler classes:
public class RestFieldError {
private String field;
private String message;
public RestFieldError() {
}
// getters and setters
}
and
public class RestFieldErrorValidation {
private List<RestFieldError> fieldErrors = new ArrayList<>();
public RestFieldErrorValidation() {
}
public void addFieldError(String path, String message) {
RestFieldError error = new RestFieldError(path, message);
fieldErrors.add(error);
}
}
RestController Code:
#RestController
#RequestMapping("/api")
public class CustomerRestController {
// autowire the CustomerService
#Autowired
private CustomerService customerService;
#InitBinder
public void initBinder(WebDataBinder dataBinder) {
System.out.println("Entered init binder");
StringTrimmerEditor stringTrimmerEditor = new StringTrimmerEditor(true);
dataBinder.registerCustomEditor(String.class, stringTrimmerEditor);
}
// add the mapping for POST/customers (add a new customer)
#PostMapping("/customers")
#ResponseBody
public Customer addCustomer(#Valid #RequestBody Customer theCustomer) {
System.out.println("theCustomer :"+theCustomer.getFirstName());
theCustomer.setId(0);
customerService.saveCustomer(theCustomer);
return theCustomer;
}
}
Exception handler Class:
#ControllerAdvice
public class GlobalExceptionHandler {
// Adding Validation Support on REST APIs--------------------------------------------------------->
private MessageSource messageSource;
#Autowired
public GlobalExceptionHandler(MessageSource messageSource) {
this.messageSource = messageSource;
}
#ExceptionHandler(MethodArgumentNotValidException.class)
#ResponseStatus(HttpStatus.BAD_REQUEST)
#ResponseBody
public RestFieldErrorValidation processValidationError(MethodArgumentNotValidException ex) {
BindingResult result = ex.getBindingResult();
List<FieldError> fieldErrors = result.getFieldErrors();
return processFieldErrors(fieldErrors);
}
private RestFieldErrorValidation processFieldErrors(List<FieldError> fieldErrors) {
RestFieldErrorValidation dto = new RestFieldErrorValidation();
for (FieldError fieldError: fieldErrors) {
String localizedErrorMessage = resolveLocalizedErrorMessage(fieldError);
dto.addFieldError(fieldError.getField(), localizedErrorMessage);
}
return dto;
}
private String resolveLocalizedErrorMessage(FieldError fieldError) {
Locale currentLocale = LocaleContextHolder.getLocale();
String localizedErrorMessage = messageSource.getMessage(fieldError, currentLocale);
//If the message was not found, return the most accurate field error code instead.
//You can remove this check if you prefer to get the default error message.
if (localizedErrorMessage.equals(fieldError.getDefaultMessage())) {
String[] fieldErrorCodes = fieldError.getCodes();
localizedErrorMessage = fieldErrorCodes[0];
}
return localizedErrorMessage;
}
}
Here is the google drive link of the project if you can check the code:
https://drive.google.com/open?id=1QSFVMi3adHGkc7BqXsqAY0P_tO2UfT2I
Here is the Article that i followed:
https://www.petrikainulainen.net/programming/spring-framework/spring-from-the-trenches-adding-validation-to-a-rest-api/
I'm assuming you are using plain Spring here, not Spring Boot.
The question is: To what exactly do you want to convert your RestFieldErrorValidation object? XML? JSON?
For either, you need an appropriate third-party library on your classpath, so Spring can do the conversion automatically.
In the case of JSON, you might want to add this dependency to your project.
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.10.2</version>
</dependency>

Java 8/Spring constants in PreAuthorize annotation

In my Spring Boot project I have defined a following RestController method:
#PreAuthorize("hasAuthority('" + Permission.APPEND_DECISION + "')")
#RequestMapping(value = "/{decisionId}/decisions", method = RequestMethod.PUT)
public DecisionResponse appendDecisionToParent(#PathVariable #NotNull #DecimalMin("0") Long decisionId, #Valid #RequestBody AppendDecisionRequest decisionRequest) {
....
return new DecisionResponse(decision);
}
Right now in order to provide allowed authority name I use a following code construction:
#PreAuthorize("hasAuthority('" + Permission.APPEND_DECISION + "')")
where Permission.APPEND_DECISION is a constant:
public static final String APPEND_DECISION = "APPEND_DECISION";
Is there any more elegant way in Java/Spring in order to define such kind of code ?
Here is a simple approach to defining authorities in a single place that doesn't require any in-depth Spring Security config.
public class Authority {
public class Plan{
public static final String MANAGE = "hasAuthority('PLAN_MANAGE')";
public static final String APPROVE = "hasAuthority('PLAN_APPROVE')";
public static final String VIEW = "hasAuthority('PLAN_VIEW')";
}
}
Securing services...
public interface PlanApprovalService {
#PreAuthorize(Authority.Plan.APPROVE)
ApprovalInfo approvePlan(Long planId);
}
}
Thanks to oli37 I have implemented this logic in a following way:
#Configuration
#EnableGlobalMethodSecurity(prePostEnabled = true, jsr250Enabled = true)
public class MethodSecurityConfig extends GlobalMethodSecurityConfiguration {
private DefaultMethodSecurityExpressionHandler defaultMethodExpressionHandler = new DefaultMethodSecurityExpressionHandler();
#Override
protected MethodSecurityExpressionHandler createExpressionHandler() {
return defaultMethodExpressionHandler;
}
public class DefaultMethodSecurityExpressionHandler extends org.springframework.security.access.expression.method.DefaultMethodSecurityExpressionHandler {
#Override
public StandardEvaluationContext createEvaluationContextInternal(final Authentication auth, final MethodInvocation mi) {
StandardEvaluationContext standardEvaluationContext = super.createEvaluationContextInternal(auth, mi);
((StandardTypeLocator) standardEvaluationContext.getTypeLocator()).registerImport(Permission.class.getPackage().getName());
return standardEvaluationContext;
}
}
}
#PreAuthorize("hasAuthority(T(Permission).APPEND_DECISION)")
#RequestMapping(value = "/{decisionId}/decisions", method = RequestMethod.PUT)
public DecisionResponse appendDecisionToParent(#PathVariable #NotNull #DecimalMin("0") Long decisionId, #Valid #RequestBody AppendDecisionRequest decisionRequest) {
...
return new DecisionResponse(decision);
}
I thing the good way is not to mixed both
You can have constants
public static final String ROLE_ADMIN = "auth_app_admin";
and have that other side
#PreAuthorize("hasRole(\"" + Constants.ROLE_ADMIN + "\")")
this is much clear

Spring-Boot Data MongoDB - How to getting a specific nested object for a super specific object

I have the following data model, and I want to get a specific object in the sub list objects, I know it's possible to get the entire list and go through each object and compare with what the search id, but I wonder if it is possible use MongoRepository to do this.
#Document
public class Host {
#Id
private String id;
#NotNull
private String name;
#DBRef
private List<Vouchers> listVoucher;
public Host() {
}
//Getters and Setters
}
And..
#Document
public class Vouchers {
#Id
private String id;
#NotNull
private int codeId;
public Vouchers() {
}
//Getters and Setters
}
The Repository Class:
public interface HostRepository extends MongoRepository<Host, String> {
List<Host> findAll();
Host findById(String id);
Host findByName(String name);
//How to build the correct query ??????????
List<Vouchers> findVouchersAll();
Vouchers findByVouchersById(String hostId, String voucherId);
}
The Controller Class:
#RestController
#RequestMapping(value = "api/v1/host")
public class VoucherController {
#Inject
HostRepository hostRepository;
#RequestMapping(value = "/{hostId}/voucher",method = RequestMethod.GET, produces = MediaType.APPLICATION_JSON_VALUE)
#ResponseBody
public List<Vouchers> list() {
return hostRepository.findVouchersAll();
}
#RequestMapping(value = "/{hostId}/voucher/{voucherId}", method = RequestMethod.GET, produces = MediaType.APPLICATION_JSON_VALUE)
#ResponseBody
public Vouchers getOneVoucher(#PathVariable String hostId, #PathVariable String voucherId) {
Vouchers voucher = hostRepository.findByVouchersById(hostId, voucherId);
if (voucher != null) {
return voucher;
} else {
throw new VoucherNotFoundException(String.format("There is no voucher with id=%s", voucherId));
}
}
}
Thanks in Advance!
I think there is a way to do this although I have not tried this myself but maybe I can shed some light in how I would do it.
Firstly, I would rather use the more flexible way of querying mongodb by using MongoTemplate. MongoTemplate is already included in the Spring Boot Mongodb data library and it looks like you are already using the library so it is not an additional library that you will have to use. In Spring there is a way to #Autowired your MongoTemplate up so it is quick and easy to get the object for completing this task.
With mongoTemplate, you would do something like this:
Query query = new Query();
query.addCriteria(Criteria.where("listVouchers.id").is("1234"));
List<Host> host = mongoTemplate.find(query, Host.class);
Please see docs here: https://docs.mongodb.org/manual/tutorial/query-documents/

Ignore fields from Java object dynamically while sending as JSON from Spring MVC

I have model class like this, for hibernate
#Entity
#Table(name = "user", catalog = "userdb")
#JsonIgnoreProperties(ignoreUnknown = true)
public class User implements java.io.Serializable {
private Integer userId;
private String userName;
private String emailId;
private String encryptedPwd;
private String createdBy;
private String updatedBy;
#Id
#GeneratedValue(strategy = IDENTITY)
#Column(name = "UserId", unique = true, nullable = false)
public Integer getUserId() {
return this.userId;
}
public void setUserId(Integer userId) {
this.userId = userId;
}
#Column(name = "UserName", length = 100)
public String getUserName() {
return this.userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
#Column(name = "EmailId", nullable = false, length = 45)
public String getEmailId() {
return this.emailId;
}
public void setEmailId(String emailId) {
this.emailId = emailId;
}
#Column(name = "EncryptedPwd", length = 100)
public String getEncryptedPwd() {
return this.encryptedPwd;
}
public void setEncryptedPwd(String encryptedPwd) {
this.encryptedPwd = encryptedPwd;
}
public void setCreatedBy(String createdBy) {
this.createdBy = createdBy;
}
#Column(name = "UpdatedBy", length = 100)
public String getUpdatedBy() {
return this.updatedBy;
}
public void setUpdatedBy(String updatedBy) {
this.updatedBy = updatedBy;
}
}
In Spring MVC controller, using DAO, I am able to get the object. and returning as JSON Object.
#Controller
public class UserController {
#Autowired
private UserService userService;
#RequestMapping(value = "/getUser/{userId}", method = RequestMethod.GET)
#ResponseBody
public User getUser(#PathVariable Integer userId) throws Exception {
User user = userService.get(userId);
user.setCreatedBy(null);
user.setUpdatedBy(null);
return user;
}
}
View part is done using AngularJS, so it will get JSON like this
{
"userId" :2,
"userName" : "john",
"emailId" : "john#gmail.com",
"encryptedPwd" : "Co7Fwd1fXYk=",
"createdBy" : null,
"updatedBy" : null
}
If I don't want to set encrypted Password, I will set that field also as null.
But I don't want like this, I dont want to send all fields to client side. If I dont want password, updatedby, createdby fields to send, My result JSON should be like
{
"userId" :2,
"userName" : "john",
"emailId" : "john#gmail.com"
}
The list of fields which I don't want to send to client coming from other database table. So it will change based on the user who is logged in. How can I do that?
I hope You got my question.
Add the #JsonIgnoreProperties("fieldname") annotation to your POJO.
Or you can use #JsonIgnore before the name of the field you want to ignore while deserializing JSON. Example:
#JsonIgnore
#JsonProperty(value = "user_password")
public String getUserPassword() {
return userPassword;
}
GitHub example
Can I do it dynamically?
Create view class:
public class View {
static class Public { }
static class ExtendedPublic extends Public { }
static class Internal extends ExtendedPublic { }
}
Annotate you model
#Document
public class User {
#Id
#JsonView(View.Public.class)
private String id;
#JsonView(View.Internal.class)
private String email;
#JsonView(View.Public.class)
private String name;
#JsonView(View.Public.class)
private Instant createdAt = Instant.now();
// getters/setters
}
Specify the view class in your controller
#RequestMapping("/user/{email}")
public class UserController {
private final UserRepository userRepository;
#Autowired
UserController(UserRepository userRepository) {
this.userRepository = userRepository;
}
#RequestMapping(method = RequestMethod.GET)
#JsonView(View.Internal.class)
public #ResponseBody Optional<User> get(#PathVariable String email) {
return userRepository.findByEmail(email);
}
}
Data example:
{"id":"5aa2496df863482dc4da2067","name":"test","createdAt":"2018-03-10T09:35:31.050353800Z"}
UPD: keep in mind that it's not best practice to use entity in response. Better use different DTO for each case and fill them using modelmapper
I know I'm a bit late to the party, but I actually ran into this as well a few months back. All of the available solutions weren't very appealing to me (mixins? ugh!), so I ended up creating a new library to make this process cleaner. It's available here if anyone would like to try it out: https://github.com/monitorjbl/spring-json-view.
The basic usage is pretty simple, you use the JsonView object in your controller methods like so:
import com.monitorjbl.json.JsonView;
import static com.monitorjbl.json.Match.match;
#RequestMapping(method = RequestMethod.GET, value = "/myObject")
#ResponseBody
public void getMyObjects() {
//get a list of the objects
List<MyObject> list = myObjectService.list();
//exclude expensive field
JsonView.with(list).onClass(MyObject.class, match().exclude("contains"));
}
You can also use it outside of Spring:
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.module.SimpleModule;
import static com.monitorjbl.json.Match.match;
ObjectMapper mapper = new ObjectMapper();
SimpleModule module = new SimpleModule();
module.addSerializer(JsonView.class, new JsonViewSerializer());
mapper.registerModule(module);
mapper.writeValueAsString(JsonView.with(list)
.onClass(MyObject.class, match()
.exclude("contains"))
.onClass(MySmallObject.class, match()
.exclude("id"));
Yes, you can specify which fields are serialized as JSON response and which to ignore.
This is what you need to do to implement Dynamically ignore properties.
1) First, you need to add #JsonFilter from com.fasterxml.jackson.annotation.JsonFilter on your entity class as.
import com.fasterxml.jackson.annotation.JsonFilter;
#JsonFilter("SomeBeanFilter")
public class SomeBean {
private String field1;
private String field2;
private String field3;
// getters/setters
}
2) Then in your controller, you have to add create the MappingJacksonValue object and set filters on it and in the end, you have to return this object.
import java.util.Arrays;
import java.util.List;
import org.springframework.http.converter.json.MappingJacksonValue;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import com.fasterxml.jackson.databind.ser.FilterProvider;
import com.fasterxml.jackson.databind.ser.impl.SimpleBeanPropertyFilter;
import com.fasterxml.jackson.databind.ser.impl.SimpleFilterProvider;
#RestController
public class FilteringController {
// Here i want to ignore all properties except field1,field2.
#GetMapping("/ignoreProperties")
public MappingJacksonValue retrieveSomeBean() {
SomeBean someBean = new SomeBean("value1", "value2", "value3");
SimpleBeanPropertyFilter filter = SimpleBeanPropertyFilter.filterOutAllExcept("field1", "field2");
FilterProvider filters = new SimpleFilterProvider().addFilter("SomeBeanFilter", filter);
MappingJacksonValue mapping = new MappingJacksonValue(someBean);
mapping.setFilters(filters);
return mapping;
}
}
This is what you will get in response:
{
field1:"value1",
field2:"value2"
}
instead of this:
{
field1:"value1",
field2:"value2",
field3:"value3"
}
Here you can see it ignores other properties(field3 in this case) in response except for property field1 and field2.
Hope this helps.
We can do this by setting access to JsonProperty.Access.WRITE_ONLY while declaring the property.
#JsonProperty( value = "password", access = JsonProperty.Access.WRITE_ONLY)
#SerializedName("password")
private String password;
Add #JsonInclude(JsonInclude.Include.NON_NULL) (forces Jackson to serialize null values) to the class as well as #JsonIgnore to the password field.
You could of course set #JsonIgnore on createdBy and updatedBy as well if you always want to ignore then and not just in this specific case.
UPDATE
In the event that you do not want to add the annotation to the POJO itself, a great option is Jackson's Mixin Annotations. Check out the documentation
I've solved using only #JsonIgnore like #kryger has suggested.
So your getter will become:
#JsonIgnore
public String getEncryptedPwd() {
return this.encryptedPwd;
}
You can set #JsonIgnore of course on field, setter or getter like described here.
And, if you want to protect encrypted password only on serialization side (e.g. when you need to login your users), add this #JsonProperty annotation to your field:
#JsonProperty(access = Access.WRITE_ONLY)
private String encryptedPwd;
More info here.
If I were you and wanted to do so, I wouldn't use my User entity in Controller layer.Instead I create and use UserDto (Data transfer object) to communicate with business(Service) layer and Controller.
You can use Apache BeanUtils(copyProperties method) to copy data from User entity to UserDto.
I have created a JsonUtil which can be used to ignore fields at runtime while giving a response.
Example Usage :
First argument should be any POJO class (Student) and ignoreFields is comma seperated fields you want to ignore in response.
Student st = new Student();
createJsonIgnoreFields(st,"firstname,age");
import java.util.logging.Logger;
import org.codehaus.jackson.map.ObjectMapper;
import org.codehaus.jackson.map.ObjectWriter;
import org.codehaus.jackson.map.ser.FilterProvider;
import org.codehaus.jackson.map.ser.impl.SimpleBeanPropertyFilter;
import org.codehaus.jackson.map.ser.impl.SimpleFilterProvider;
public class JsonUtil {
public static String createJsonIgnoreFields(Object object, String ignoreFields) {
try {
ObjectMapper mapper = new ObjectMapper();
mapper.getSerializationConfig().addMixInAnnotations(Object.class, JsonPropertyFilterMixIn.class);
String[] ignoreFieldsArray = ignoreFields.split(",");
FilterProvider filters = new SimpleFilterProvider()
.addFilter("filter properties by field names",
SimpleBeanPropertyFilter.serializeAllExcept(ignoreFieldsArray));
ObjectWriter writer = mapper.writer().withFilters(filters);
return writer.writeValueAsString(object);
} catch (Exception e) {
//handle exception here
}
return "";
}
public static String createJson(Object object) {
try {
ObjectMapper mapper = new ObjectMapper();
ObjectWriter writer = mapper.writer().withDefaultPrettyPrinter();
return writer.writeValueAsString(object);
}catch (Exception e) {
//handle exception here
}
return "";
}
}
I've found a solution for me with Spring and jackson
First specify the filter name in the entity
#Entity
#Table(name = "SECTEUR")
#JsonFilter(ModelJsonFilters.SECTEUR_FILTER)
public class Secteur implements Serializable {
/** Serial UID */
private static final long serialVersionUID = 5697181222899184767L;
/**
* Unique ID
*/
#Id
#JsonView(View.SecteurWithoutChildrens.class)
#Column(name = "id")
#GeneratedValue(strategy = GenerationType.IDENTITY)
private long id;
#JsonView(View.SecteurWithoutChildrens.class)
#Column(name = "code", nullable = false, length = 35)
private String code;
/**
* Identifiant du secteur parent
*/
#JsonView(View.SecteurWithoutChildrens.class)
#Column(name = "id_parent")
private Long idParent;
#OneToMany(fetch = FetchType.LAZY)
#JoinColumn(name = "id_parent")
private List<Secteur> secteursEnfants = new ArrayList<>(0);
}
Then you can see the constants filters names class with the default FilterProvider used in spring configuration
public class ModelJsonFilters {
public final static String SECTEUR_FILTER = "SecteurFilter";
public final static String APPLICATION_FILTER = "ApplicationFilter";
public final static String SERVICE_FILTER = "ServiceFilter";
public final static String UTILISATEUR_FILTER = "UtilisateurFilter";
public static SimpleFilterProvider getDefaultFilters() {
SimpleBeanPropertyFilter theFilter = SimpleBeanPropertyFilter.serializeAll();
return new SimpleFilterProvider().setDefaultFilter(theFilter);
}
}
Spring configuration :
#EnableWebMvc
#Configuration
#ComponentScan(basePackages = "fr.sodebo")
public class ApiRootConfiguration extends WebMvcConfigurerAdapter {
#Autowired
private EntityManagerFactory entityManagerFactory;
/**
* config qui permet d'éviter les "Lazy loading Error" au moment de la
* conversion json par jackson pour les retours des services REST<br>
* on permet à jackson d'acceder à sessionFactory pour charger ce dont il a
* besoin
*/
#Override
public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
super.configureMessageConverters(converters);
MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter();
ObjectMapper mapper = new ObjectMapper();
// config d'hibernate pour la conversion json
mapper.registerModule(getConfiguredHibernateModule());//
// inscrit les filtres json
subscribeFiltersInMapper(mapper);
// config du comportement de json views
mapper.configure(MapperFeature.DEFAULT_VIEW_INCLUSION, false);
converter.setObjectMapper(mapper);
converters.add(converter);
}
/**
* config d'hibernate pour la conversion json
*
* #return Hibernate5Module
*/
private Hibernate5Module getConfiguredHibernateModule() {
SessionFactory sessionFactory = entityManagerFactory.unwrap(SessionFactory.class);
Hibernate5Module module = new Hibernate5Module(sessionFactory);
module.configure(Hibernate5Module.Feature.FORCE_LAZY_LOADING, true);
return module;
}
/**
* inscrit les filtres json
*
* #param mapper
*/
private void subscribeFiltersInMapper(ObjectMapper mapper) {
mapper.setFilterProvider(ModelJsonFilters.getDefaultFilters());
}
}
Endly I can specify a specific filter in restConstoller when i need....
#RequestMapping(value = "/{id}/droits/", method = RequestMethod.GET)
public MappingJacksonValue getListDroits(#PathVariable long id) {
LOGGER.debug("Get all droits of user with id {}", id);
List<Droit> droits = utilisateurService.findDroitsDeUtilisateur(id);
MappingJacksonValue value;
UtilisateurWithSecteurs utilisateurWithSecteurs = droitsUtilisateur.fillLists(droits).get(id);
value = new MappingJacksonValue(utilisateurWithSecteurs);
FilterProvider filters = ModelJsonFilters.getDefaultFilters().addFilter(ModelJsonFilters.SECTEUR_FILTER, SimpleBeanPropertyFilter.serializeAllExcept("secteursEnfants")).addFilter(ModelJsonFilters.APPLICATION_FILTER,
SimpleBeanPropertyFilter.serializeAllExcept("services"));
value.setFilters(filters);
return value;
}
Place #JsonIgnore on the field or its getter, or create a custom dto
#JsonIgnore
private String encryptedPwd;
or as mentioned above by ceekay annotate it with #JsonProperty where access attribute is set to write only
#JsonProperty( value = "password", access = JsonProperty.Access.WRITE_ONLY)
private String encryptedPwd;
Can I do it dynamically?
Yes, you can use a combination of Jackson's PropertyFilter and mixins.
Explanation
Jackson has a PropertyFilter interface to implement a filter to ignore fields dynamically. The problem is that filter has to be defined on the DTO/POJO class using the #JsonFilter annotation.
To avoid adding a #JsonFilter on class we can use ObjectMapper's addMixIn method to "dynamically" add this annotation (and leave our DTO/POJO classes as is).
Code example
Here is my implementation of the idea provided above. We can call toJson() with two arguments: (1) object to be serialized and (2) lambda (Java's Predicate) to be used in PropertyFilter:
public class JsonService {
public String toJson(Object object, Predicate<PropertyWriter> filter) {
ObjectMapper mapper = new ObjectMapper();
FilterProvider filterProvider = new SimpleFilterProvider()
.addFilter("DynamicFilter", new DynamicFilter(filter));
mapper.setFilterProvider(filterProvider);
mapper.addMixIn(object.getClass(), DynamicFilterMixin.class);
try {
return mapper.writeValueAsString(object);
} catch (JsonProcessingException e) {
throw new MyException(e);
}
}
private static final class DynamicFilter extends SimpleBeanPropertyFilter {
private Predicate<PropertyWriter> filter;
private DynamicFilter(Predicate<PropertyWriter> filter) {
this.filter = filter;
}
protected boolean include(BeanPropertyWriter writer) {
return include((PropertyWriter) writer);
}
protected boolean include(PropertyWriter writer) {
return filter.test(writer);
}
}
#JsonFilter("DynamicFilter")
private interface DynamicFilterMixin {
}
}
Now we can call toJson and filter fields during a serialization:
Filtering by name
new JsonService().toJson(object, w -> !w.getName().equals("fieldNameToBeIgnored"));
Filtering by annotation (on the field)
new JsonService().toJson(object, w -> w.getAnnotation(MyAnnotation.class) == null);
Unit tests
Here are the unit tests for the class above:
public class JsonServiceTest {
private JsonService jsonService = new JsonService();
#Test
public void withoutFiltering() {
MyObject object = getObject();
String json = jsonService.toJson(object, w -> true);
assertEquals("{\"myString\":\"stringValue\",\"myInteger\":10,\"myBoolean\":true}", json);
}
#Test
public void filteredByFieldName() {
MyObject object = getObject();
String json = jsonService.toJson(object, w -> !w.getName().equals("myString"));
assertEquals("{\"myInteger\":10,\"myBoolean\":true}", json);
}
#Test
public void filteredByAnnotation() {
MyObject object = getObject();
String json = jsonService.toJson(object, w -> w.getAnnotation(Deprecated.class) == null);
assertEquals("{\"myString\":\"stringValue\",\"myInteger\":10}", json);
}
private MyObject getObject() {
MyObject object = new MyObject();
object.myString = "stringValue";
object.myInteger = 10;
object.myBoolean = true;
return object;
}
private static class MyObject {
private String myString;
private int myInteger;
#Deprecated
private boolean myBoolean;
public String getMyString() {
return myString;
}
public void setMyString(String myString) {
this.myString = myString;
}
public int getMyInteger() {
return myInteger;
}
public void setMyInteger(int myInteger) {
this.myInteger = myInteger;
}
public boolean isMyBoolean() {
return myBoolean;
}
public void setMyBoolean(boolean myBoolean) {
this.myBoolean = myBoolean;
}
}
}
Would not creating a UserJsonResponse class and populating with the wanted fields be a cleaner solution?
Returning directly a JSON seems a great solution when you want to give all the model back. Otherwise it just gets messy.
In the future, for example you might want to have a JSON field that does not match any Model field and then you're in a bigger trouble.
This is a clean utility tool for the above answer :
#GetMapping(value = "/my-url")
public #ResponseBody
MappingJacksonValue getMyBean() {
List<MyBean> myBeans = Service.findAll();
MappingJacksonValue mappingValue = MappingFilterUtils.applyFilter(myBeans, MappingFilterUtils.JsonFilterMode.EXCLUDE_FIELD_MODE, "MyFilterName", "myBiggerObject.mySmallerObject.mySmallestObject");
return mappingValue;
}
//AND THE UTILITY CLASS
public class MappingFilterUtils {
public enum JsonFilterMode {
INCLUDE_FIELD_MODE, EXCLUDE_FIELD_MODE
}
public static MappingJacksonValue applyFilter(Object object, final JsonFilterMode mode, final String filterName, final String... fields) {
if (fields == null || fields.length == 0) {
throw new IllegalArgumentException("You should pass at least one field");
}
return applyFilter(object, mode, filterName, new HashSet<>(Arrays.asList(fields)));
}
public static MappingJacksonValue applyFilter(Object object, final JsonFilterMode mode, final String filterName, final Set<String> fields) {
if (fields == null || fields.isEmpty()) {
throw new IllegalArgumentException("You should pass at least one field");
}
SimpleBeanPropertyFilter filter = null;
switch (mode) {
case EXCLUDE_FIELD_MODE:
filter = SimpleBeanPropertyFilter.serializeAllExcept(fields);
break;
case INCLUDE_FIELD_MODE:
filter = SimpleBeanPropertyFilter.filterOutAllExcept(fields);
break;
}
FilterProvider filters = new SimpleFilterProvider().addFilter(filterName, filter);
MappingJacksonValue mapping = new MappingJacksonValue(object);
mapping.setFilters(filters);
return mapping;
}
}
To acheive dynamic filtering follow the link - https://iamvickyav.medium.com/spring-boot-dynamically-ignore-fields-while-converting-java-object-to-json-e8d642088f55
Add the #JsonFilter("Filter name") annotation to the model class.
Inside the controller function add the code:-
SimpleBeanPropertyFilter simpleBeanPropertyFilter =
SimpleBeanPropertyFilter.serializeAllExcept("id", "dob");
FilterProvider filterProvider = new SimpleFilterProvider()
.addFilter("Filter name", simpleBeanPropertyFilter);
List<User> userList = userService.getAllUsers();
MappingJacksonValue mappingJacksonValue = new MappingJacksonValue(userList);
mappingJacksonValue.setFilters(filterProvider);
return mappingJacksonValue;
make sure the return type is MappingJacksonValue.
Hi I have achieved dynamic filtering by using Gson library like in the below:
JsonObject jsonObj = new Gson().fromJson(mapper.writeValueAsString(sampleObject), JsonObject.class);
jsonObj.remove("someProperty");
String data = new Gson().toJson(jsonObj);
In your entity class add #JsonInclude(JsonInclude.Include.NON_NULL) annotation to resolve the problem
it will look like
#Entity
#JsonInclude(JsonInclude.Include.NON_NULL)

Categories