I Am Using Spring Boot in which i want a method to get details of person with its land details .
A person can have any number of lands.
I have created a following method but it is not working
#PutMapping("/fl-details/{f}/{l}")
#Timed
public ResponseEntity<PersonDetailsDTO> updateDetails(#RequestParam("f") PersonDetailsDTO personDetailsDTO,
#RequestParam("l") List<LandDetailsDTO> landDetailsDTOS) throws URISyntaxException {
if (personDetailsDTO.getId() == null || landDetailsDTOS.iterator().next().getId() == null) {
return createFarmerDetails(personDetailsDTO,landDetailsDTOS);
}
PersonDetailsDTO result = personDetailsService.save(personDetailsDTO);
landDetailsDTOS.stream().forEach(landDetailsService::save);
return ResponseEntity.ok()
.headers(HeaderUtil.createEntityUpdateAlert(ENTITY_PERSON+ENTITY_LAND, personDetailsDTO.getId().toString()))
.body(result);
}
I can post person details from
#ResponseBody PersonDetailsDTO personDetailsDTO
but i am getting confused in post both of these.
Could anyone tell me how could i post two different Kind Of JSON objects in Spring Boot API
A #RequestParam cannot be deserialised to a PersonDetailsDTO or LandDetailsDTO (unless you implement a custom converter) so in order to pass a complex object (whether it is of type PersonDetailsDTO or type LandDetailsDTO) you must use #ResponseBody.
And since a controller method can only have one #ResponseBody you'll have to pass in a composite object i.e. one which could contain either a PersonDetailsDTO or a LandDetailsDTO. For example:
class CompositeDto {
private PersonDetailsDTO personDetails;
private List<LandDetailsDTO> landDetails
}
And then interrogate this inside your controller method, for example:
if (compositeDto.containsPersonDetails()) {
// ...
} else if (compositeDto.containsLandDetails()) {
// ...
}
Related
I am used to JAX-RS and would like to have similar comfort when sending requests using Spring MVC and working with the responses, i.e. on the client side inside my tests.
On the server (controller) side I'm quite happy with the automatic conversion, i.e. it suffices to just return an object instance and have JSON in the resulting HTTP response sent to the client.
Could you tell me how to work around the manual process of converting objectInstance to jsonString or vice versa in these snippets? If possible, I'd also like to skip configuring the content type manually.
String jsonStringRequest = objectMapper.writeValueAsString(objectInstance);
ResultActions resultActions = mockMvc.perform(post(PATH)
.contentType(MediaType.APPLICATION_JSON)
.content(jsonStringRequest)
)
String jsonStringResponse = resultActions.andReturn().getResponse().getContentAsString();
Some objectInstanceResponse = objectMapper.readValue(jsonStringResponse, Some.class);
For comparison, with JAX-RS client API I can easily send an object using request.post(Entity.entity(objectInstance, MediaType.APPLICATION_JSON_TYPE) and read the response using response.readEntity(Some.class);
if you have lot's of response objects, you could create some generic JsonToObject mapper-factory. It could be then used to detect the object type from a generic response (all response objects inherit from the same generic class) and respond/log properly from a bad mapping attempt.
I do not have a code example at hand, but as a pseudocode:
public abstract GenericResponse {
public String responseClassName = null;
// get/set
}
In the server code, add the name of the actual response object to this class.
The JsonToObject factory
public ConverterFactory<T> {
private T objectType;
public ConverterFactory(T type) {
objectType = type;
}
public T convert(String jsonString) {
// Type check
GenericResponse genResp = mapper.readValue(result.getResponse().getContentAsString(),
GenericResponse.class);
if (objectType.getClass().getSimpleName().equals(genResp.getResponseClassName())) {
// ObjectMapper code
return mapper.readValue(result.getResponse().getContentAsString(),
objectType.class);
} else {
// Error handling
}
}
}
I think this could be extended to be used with annotation to do more automation magic with the response. (start checking with BeanPostProcessor)
#Component
public class AnnotationWorker implements BeanPostProcessor {
#Override
public Object postProcessBeforeInitialization(final Object bean, String name) throws BeansException {
ReflectionUtils.doWithFields(bean.getClass(), field -> {
// make the field accessible if defined private
ReflectionUtils.makeAccessible(field);
if (field.getAnnotation(MyAnnotation.class) != null) {
field.set(bean, log);
}
});
return bean;
}
}
The above code snippet is copied from my current project and it injects to fields, you need to change it so, that it works for methods, eg ... where you may need it.
Having this all implemented may be tricky and can't say it necessarily works even, but it's something to try if you don't mind a bit of educative work.
I've defined and registered some custom marshallers for my domain objects. If used alone, just rendering one instance, works fine, but the problem comes when I return a map with an array of those instances. In this moment my custom marshaller is not beign invoked.
This is one of my marshallers:
class BackendCompanyMarshaller implements ObjectMarshaller<JSON> {
#Override
public boolean supports(Object object) {
object instanceof Company
}
#Override
public void marshalObject(Object object, JSON converter)
throws ConverterException {
JSONWriter writer = converter.getWriter()
writer.object()
writer.key('id').value(object.id)
.key('name').value(object.name?.encodeAsHTML()?:'')
.key('description').value(object.description?.encodeAsHTML()?:'')
.key('enterprise').value(object.enterprise?.encodeAsHTML()?:'')
writer.endObject()
}
}
Ans for example this is what I'm returning from my controller:
render text:[achievements:arrayOfAchievements, total:2] as JSON
In previous versions of grails I know there was deep marshallers but I haven't been able to find something similar for grails 3.
I have also tried to implement a custom marshaller for List, but I'm not sure what I should return or write.
Suppose I have two sets of controllers in Spring:
/jsonapi1/*
/jsonapi2/*
both of which return objects that are to be interpretted as JSON text.
I'd like some kind of filter to wrap the responses from one set of these controllers so that:
the original response is contained within another object.
For example, if /jsonapi1/count returns:
{"num_humans":123, "num_androids":456}
then the response should be wrapped and returned as follows:
{ "status":0,
"content":{"num_humans":123, "num_androids":456}
}
if an exception happens in the controller, then filter should catch the exception and report it as follows
{ "status":5,
"content":"Something terrible happened"
}
The responses from the other controllers are returned unchanged.
We're currently customizing a MappingJackson2HttpMessageConverter passed to WebMvcConfigurerAdapter.configureMessageConverters in order to perform the above tasks. Works great except that it doesn't seem possible for this approach to be selective about the URLs (or controller classes) it applies to.
Is it possible to apply these kinds of wrappers to individual controller classes or URLs?
Update: Servlet filters look like a solution. Is it possible chose which filter gets applied to which controller methods, or which URLs?
I was struggling on this for multiple days. The solution by #Misha didn't work for me. I was able to finally get this working using ControllerAdvice and ResponseBodyAdvice.
ResponseBodyAdvice allows to inject custom transformation logic on the response returned by a controller but before it is converted to HttpResponse and committed.
This is how my controller method looks:
#RequestMapping("/global/hallOfFame")
public List<HallOfFame> getAllHallOfFame() {
return hallOfFameService.getAllHallOfFame();
}
Now i wanted to add some standard fields around the response like devmessage and usermessage. That logic goes into the ResponseAdvice:
#ControllerAdvice
public class TLResponseAdvice implements ResponseBodyAdvice<Object> {
#Override
public boolean supports(MethodParameter returnType, Class<? extends HttpMessageConverter<?>> converterType) {
return true;
}
#Override
public Object beforeBodyWrite(Object body, MethodParameter returnType, MediaType selectedContentType,
Class<? extends HttpMessageConverter<?>> selectedConverterType, ServerHttpRequest request,
ServerHttpResponse response) {
// TODO Auto-generated method stub
final RestResponse<Object> output = new RestResponse<>();
output.setData(body);
output.setDevMessage("ResponseAdviceDevMessage");
output.setHttpcode(200);
output.setStatus("Success");
output.setUserMessage("ResponseAdviceUserMessage");
return output;
}
}
The entity classes look like this:
#Setter // All lombok annotations
#Getter
#ToString
public class RestResponse<T> {
private String status;
private int httpcode;
private String devMessage;
private String userMessage;
private T data;
}
#Entity
#Data // Lombok
public class HallOfFame {
#Id
private String id;
private String name;
}
To handle exceptions, simply create another ControllerAdvice with ExceptionHandler. Use the example in this link.
Advantages of this solution:
It keeps your controllers clean. You can support any return type from your controller methods.
Your controller return type class does not need to extend some base class as required by the AOP approach.
You do not need to hack your way through Spring filters by using HttpServletResponseWrappers. They come up with a performance penalty.
EDIT - 17th September 2019
To handle exceptions use #ExceptionHandler. Refer code below.
#ExceptionHandler(Exception.class)
#ResponseBody
public MyResponseEntity<Object> handleControllerException(HttpServletRequest request, Throwable ex) {
// default value
int httpCode = HttpStatus.INTERNAL_SERVER_ERROR.value();
if(ex instanceof ResourceNotFoundException) {
httpCode = HttpStatus.NOT_FOUND.value();
}
...
}
The way I understand your question, you have exactly three choices.
Option #1
Manually wrap your objects in simple SuccessResponse, ErrorResponse, SomethingSortOfWrongResponse, etc. objects that have the fields you require. At this point, you have per-request flexibility, changing the fields on one of the response wrappers is trivial, and the only true drawback is code repetition if many of the controller's request methods can and should be grouped together.
Option #2
As you mentioned, and filter could be designed to do the dirty work, but be wary that Spring filters will NOT give you access to request or response data. Here's an example of what it might look like:
#Component
public class ResponseWrappingFilter extends GenericFilterBean {
#Override
public void doFilter(
ServletRequest request,
ServletResponse response,
FilterChain chain) {
// Perform the rest of the chain, populating the response.
chain.doFilter(request, response);
// No way to read the body from the response here. getBody() doesn't exist.
response.setBody(new ResponseWrapper(response.getStatus(), response.getBody());
}
}
If you find a way to set the body in that filter, then yes, you could easily wrap it up. Otherwise, this option is a dead end.
Option #3
A-ha. So you got this far. Code duplication is not an option, but you insist on wrapping responses from your controller methods. I'd like to introduce the true solution - aspect-oriented programming (AOP), which Spring supports fondly.
If you're not familiar with AOP, the premise is as follows: you define an expression that matches (like a regular expression matches) points in the code. These points are called join points, while the expressions that match them are called pointcuts. You can then opt to execute additional, arbitrary code, called advice, when any pointcut or combination of pointcuts are matched. An object that defines pointcuts and advice is called an aspect.
It's great for expressing yourself more fluently in Java. The only drawback is weaker static type checking. Without further ado, here's your response-wrapping in aspect-oriented programming:
#Aspect
#Component
public class ResponseWrappingAspect {
#Pointcut("within(#org.springframework.stereotype.Controller *)")
public void anyControllerPointcut() {}
#Pointcut("execution(* *(..))")
public void anyMethodPointcut() {}
#AfterReturning(
value = "anyControllerPointcut() && anyMethodPointcut()",
returning = "response")
public Object wrapResponse(Object response) {
// Do whatever logic needs to be done to wrap it correctly.
return new ResponseWrapper(response);
}
#AfterThrowing(
value = "anyControllerPointcut() && anyMethodPointcut()",
throwing = "cause")
public Object wrapException(Exception cause) {
// Do whatever logic needs to be done to wrap it correctly.
return new ErrorResponseWrapper(cause);
}
}
The final result will be the non-repeating response wrapping that you seek. If you only want some or one controller receive this effect, then update the pointcut to match methods only within instances of that controller (rather than any class holding the #Controller annotation).
You'll need to include some AOP dependencies, add the AOP-enabling annotation in a configuration class, and make sure something component-scans the package this class is in.
Simplest way i manage custom responses from controllers is by utilising the Map variable.
so your code ends up looking like:
public #ResponseBody Map controllerName(...) {
Map mapA = new HashMap();
mapA.put("status", "5");
mapA.put("content", "something went south");
return mapA;
}
beauty of is is that you can configure it any thousand ways.
Currently i use for object transmition, custom exception handling and data reporting, too easy.
Hope this helps
I am also using AOP with #Around. Developed a custom annotation and using that for point cut. I am using a global Response. It has the status, Message and data which is of type List of type
List <? extends parent> dataList
( which can solve your class cast exception). All the entities extends this Parent class. This way I can set all the data into my List.
Also I am using the message key as param with the custom annotation and setting it in action.
Hope this helps.
I keep getting Bad request 400 when trying to POST this array of JSON objects "sorry bad format":
{
"type":"input","uniqueId":434,"label":"name","viewToCall":"input-configuration-menu"},{"type":"button","uniqueId":930,"label":"name","viewToCall":"button-configuration-menu"}]
Im not sure how to handel different type of json object in my #Requestbody:
#RequestMapping(value="/saveForm", method = RequestMethod.POST)
public #ResponseBody void saveForm( #RequestBody ArrayList<Components> text ){
do somthing...
}
I found this resourcer but I dont have the experience to get it to work i n web environment:
Spring #RequestBody containing a list of different types (but same interface)
http://programmerbruce.blogspot.com.es/2011/05/deserialize-json-with-jackson-into.html
http://aredko.blogspot.se/2012/04/json-for-polymorhic-java-object.html
There is a missing [ at the beginning of the JSON, otherwise it's valid JSON. If the problem is not the missing angle bracket, put the logs in DEBUG or TRACE, and post the stacktrace.
Also the components need to be annotated with something like this, in order for Jackson to know which object need to be instantiated (see also Jackson polymorphism without annotations):
#JsonTypeInfo(use=JsonTypeInfo.Id.NAME, include=As.WRAPPER_OBJECT)
#JsonSubTypes({
#Type(value=Input.class, value="input"),
#Type(value=Button.class, value="button")})
public interface Component {
...
}
#JsonTypeName("type")
public Sub1 implements Component {
}
#JsonTypeName("button")
public Button implements Component {
}
I need to work with data returned from a service which has a more complex JSON structure than the examples provided in the GXT documentation and thus far I cannot find any instructions or example which demonstrates how this might be accomplished.
The JSON contains multiple key/value pairs, but some of the key/value pairs are collections. I can have all of the data returned to me in one call from the service in the proper structure, but there does not appear to be a way to parse the data into separate entities. In my particular case I am attempting to configure a loader which will process one of the collections but I also need other key/value pairs from the same message (it is not ok to have the loader make one call and then have another call made for the same data and retrieve the other key/value pairs). Is there any way to accomplish this using GXT3?
Example: let's assume I can make a request from a server which returns JSON containing the name of an author along with a collection of the books the author has written. I want to display the author's name above a grid which lists the books. I want only one request made to the server and then have my view display the author in one component and the book list in a grid. Assume I need a loader instead of just a store as the grid may have to make additional calls (e.g. if it is a paging grid, livegrid, etc.).
Example JSON: (one JSON message returned with and author element along with a collection of book elements - I've indented the JSON to illustrate the structure)
{ "returnData" :
{"author" : "AuthorName"},
{"books" :
{"id" : "1", "name" : "Book1"},{"id" : "2", "name" : "Book2"}
}
}
Using the example for JsonReader (see the javadoc for an example) I can receive the request and parse the links into a collection using AutoBeans. This works fine when I need to have those retrieved and parsed in a loader. However, if I do that then the other properties are ignored. I currently don't see any way to parse the other values in the same request so they can be used elsewhere. My example code for the collection processing is below:
// this is the root JSON object, the AuthorRecord
public interface AuthorRecord {
#PropertyName(value="author")
String getAuthor();
#PropertyName(value="author")
void setAuthor(String author);
#PropertyName(value="books")
List<Book> getBooks();#
#PropertyName(value="books")
void setBooks (List<Book> books);
}
// models the book objects returned
public interface Book {
#PropertyName(value="id")
String getId();
#PropertyName(value="id")
void setId(String id);
#PropertyName(value="name")
String getName();
#PropertyName(value="name")
void setName(String name);
}
public interface ReturnData {
AuthorRootObject getAuthorRoot();
}
public interface LibraryAutoBeanFactory extends AutoBeanFactory {
AutoBean<ReturnData> authorRecord();
AutoBean<ListLoadConfig> loadConfig();
}
public class ReturnDataJsonReader extends JsonReader<ListLoadResult<Book>,
ReturnData> {
public ReturnDataJsonReader(AutoBeanFactory factory,
Class<ReturnData> rootBeanType) {
super(factory, rootBeanType);
}
#Override
protected ListLoadResultBean<Book> createReturnData(Object loadConfig,
ReturnData incomingData) {
return new ListLoadResultBean<Book>(incomingData.getBooks());
}
}
The problem I was having was that I need to have a view that includes a grid (paging grid, etc.) which lists out the books, while having the Author's name sit above the grid. I wanted to get all of this information (or at least the first page of results) with only one request to the server since the JSON message contains all the information I need to accomplish this. The problem is that the loader makes the request and receives the response, and it expects that the reader it will use is going to process a collection. In my case, I need the loader to process the collection of books but also populate another data field. The solution I found was to create an arbitrary collection to pass to the loader and then implement my own load handler to process the return object as needed.
1.The JSON being returned is really just one object of type ReturnData. The extended JsonReader could process this using AutoBeans, but if the reader is to be used for the loader, it needs to return a collection. Therefore, override the createReturnData() method to return a collection of one object.
public class ReturnDataJsonReader extends JsonReader<ListLoadResult<AuthorRecord>,
ReturnData> {
public ReturnDataJsonReader(AutoBeanFactory factory, Class<ReturnData> rootBeanType)
{
super(factory, rootBeanType);
}
#Override
protected ListLoadResultBean<AuthorRecord> createReturnData(Object loadConfig,
ReturnData incomingData) {
List<AuthorRecord> authorDataCollection = new ArrayList<AuthorRecord>();
authorDataCollection.add(incomingData);
return authorDataCollection;
}
}
2.The LoadHandler used in the examples takes a ListStore as an input and populates it with the results from the loader. Since the return object is not what we want populating the loader, and since we need to populate another property on the view, create your own LoadHandler to take the objects needed as input and populate them:
View Class Example:
public class ExampleViewClass {
// truncating most of the code in here for brevity
// note some of the objects referenced here reference objects in the question
private String authorName;
private ListStore<Book> bookList;
// IMPORTANT - create your own LoadHandler
private class LibraryLoadResultistStoreBinding<C, M, D extends
ListLoadResult<AuthorRecord>> implements LoadHandler<ListLoadConfig,
ListLoadResult<AuthorRecord>> {
private final ListStore<Book> bookStore;
private final String authorName;
public LibraryLoadResultistStoreBinding(ListStore<Book> books, String author) {
this.bookStore = books;
this.authorName = author;
}
#Override
public void onLoad(LoadEvent<ListLoadConfig, ListLoadResult<AuthorRecord> event)
{
// the response object
AuthorRecord response = event.getLoadResult().getData().get(0);
bookStore.replaceAll(response.getBooks());
author = response.getAuthor();
}
}
// example uses an HttpProxy but that's not required
public void populateView() {
LibraryAutoBeanFactory factory = GWT.create(LibraryAutoBeanFactory.class);
ReturnDataJsonReader reader = new ReturnDataJsonReader(factory, ReturnData.class);
String path = "http://path.to.resource/getinfo";
RequestBuilder builder = new RequestBuilder(RequestBuilder.GET, path);
HttpProxy<ListLoadConfig> proxy = new HttpProxy<ListLoadConfig>(builder);
final ListLoader<ListLoadConfig, ListLoadResult<AuthorRecord>> loader = new
ListLoader<ListLoadConfig, ListLoadResult<AuthorRecord>> (proxy, reader);
loader.useLoadConfig(ReturnDataAutoBeanFactory.instance.loadConfig().as();
loader.addLoadHandler(new LibraryLoadResultistStoreBinding<ListLoadConfig,
AuthorRecord, ListLoadResult<AuthorRecord>>(bookList, authorName);
// pass in the objects to be populated
loader.load(); // fire the loader
}