I have to send JSON data from one service method to the other using postForObject() method.
I saw one example on RestTemplate on this link.
postForObject() method has the following format:
User returns = rt.postForObject(uri, u, User.class, vars);
Or
User returns = rt.postForObject(uri, u, User.class);
I want to know that, after using postForObject() method, if we implement the service method to accept the User object, how it will look like?
In my project, I have code like
RestTemplate restTemplate = new RestTemplate();
restTemplate.getMessageConverters().add(new MappingJacksonHttpMessageConverter());
restTemplate.getMessageConverters().add(new StringHttpMessageConverter());
String uri = "http://testcode.com/myapp/api/launchservices";
ServiceRequest request = new ServiceRequest();
request.setId(UUID.randomUUID().toString());
....
I am getting error at this line:
ServiceRequest req = restTemplate.postForObject(uri, request, ServiceRequest.class);
while executing this, I am getting this error mesage:
org.springframework.web.client.HttpClientErrorException: 400 Bad Request
at org.springframework.web.client.DefaultResponseErrorHandler.handleError(DefaultResponseErrorHandler.java:88)
at org.springframework.web.client.RestTemplate.handleResponseError(RestTemplate.java:537)
at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:493)
at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:452)
at org.springframework.web.client.RestTemplate.postForObject(RestTemplate.java:302)
my implementation method is:
#RequestMapping(value = "/launchservices", method = RequestMethod.POST)
#ResponseBody
public boolean launchServices(#PathVariable ServiceRequest request) {
System.out.println("Request: "+request.toString());
return true;
}
How to get rid of this? What will be the URI?
I got solution to this problem.
In this example,method postForObject returns an object of class "ServiceRequest"
ServiceRequest req = restTemplate.postForObject(uri, request, ServiceRequest.class);
So, the method that implements this service with the above 'uri' should return an object of class ServiceRequest
All it needs is, slight modification in implementation method as below
#RequestMapping(value = "/launchservices", method = RequestMethod.POST, headers = "Accept=application/json")
#ResponseBody
public ServiceRequest launchServices(#RequestBody ServiceRequest request) {
System.out.println("Request: "+request.toString());
return request;
}
Related
I have the following situation:
My REST API one:
#RestController
#RequestMapping("/controller1")
Public Class Controller1{
#RequestMapping(method = RequestMethod.POST)
public void process(#RequestBody String jsonString) throws InterruptedException, ExecutionException
{
............
}
}
JSON POST request, request1, for the REST API(Controller1):
{
"key1":"value1",
"key2":"value2"
}
My REST API two:
#RestController
#RequestMapping("/controller2")
Public Class Controller2{
#RequestMapping(method = RequestMethod.POST)
public void process(#RequestBody String jsonString) throws InterruptedException, ExecutionException
{
............
}
}
JSON request, request2, for the REST API(Controller2):
{
"key1":"value1",
"key2":"value2",
"key3":"value3"
}
I have several such "primitive" requests.
Now, I am expecting a JSON request, let's call it request3, which is a combination of such "primitive" queries- something that looks like below:
{
{
"requestType":"requestType1",
"request":"[{"key1":"value1","key2":"value2"}]"
},
{
"requestType":"requestType2",
"request":"[{"key1":"value1","key2":"value2","key3":"value3"}]"
}
}
Here, I need to trigger the respective API (one or two) upon identifying the query type. I wanna know how I can forward the request to the corresponding REST API. I wrote the REST API for request3 like below:
#RestController
#RequestMapping("/controller3")
Public Class Controller3{
#RequestMapping(method = RequestMethod.POST)
public void process(#RequestBody String jsonString) throws InterruptedException, ExecutionException
{
..................
..................
switch(request){
case request1: //how to call REST API 1?
case request2: //how to call REST API 2?
}
}
}
You can call a utility method which posts request to controller using Rest Template as below. Since you are using POST method it's easy to send parameters using Rest Template. You may need to edit this code a bit to work in your environment with exact syntax.
#RequestMapping( value= "/controller3" method = RequestMethod.POST)
public #ResponseBody void process(#RequestBody String jsonString){
String request = requestType //Get the request type from request
String url = "";
MultiValueMap<String, String> params= null;
switch(request){
case request1: //how to call REST API 1?
url = "/controller1";
params = request1param //Get the parameter map from request
case request2: //how to call REST API 2?
url = "/controller2";
params = request2Param //Get the parameter map from request
}
//Now call the method with parameters
getRESTResponse(url, params);
}
private String getRESTResponse(String url, MultiValueMap<String, String> params){
RestTemplate template = new RestTemplate();
HttpEntity<MultiValueMap<String, String>> requestEntity=
new HttpEntity<MultiValueMap<String, String>>(params);
String response = "";
try{
String responseEntity = template.exchange(url, HttpMethod.POST, requestEntity, String.class);
response = responseEntity.getBody();
}
catch(Exception e){
response = e.getMessage();
}
return response;
}
Redirect from one controller method to another controller method
Alternatively you also can call the rest method using Rest Template
Spring MVC - Calling a rest service from inside another rest service
You may find how to send POST request with params in this post
https://techie-mixture.blogspot.com/2016/07/spring-rest-template-sending-post.html
I want to build a small RESTful Service, send a PUT request with an Object of a class I created (MyObject), and getting a response with only status.
My controler:
#RestController
public class MyControler {
#RequestMapping(path = "/blabla/{id}", method = RequestMethod.PUT)
#ResponseBody
public ResponseEntity<String> putMethod (#PathVariable("id") Long id,
#RequestBody MyObject t) {
/*todo*/
return new ResponseEntity<String>(HttpStatus.OK);
}
My Test App
#SpringBootApplication
public class App {
public String httpPut(String urlStr) {
MyObject myObject = new MyObject(p,p,....);
URI url = null;
HttpEntity<MyObject> requestEntity;
RestTemplate rest = new RestTemplate();
rest.getMessageConverters().add(new MappingJackson2HttpMessageConverter());
HttpHeaders headers = new HttpHeaders();
List<MediaType> list = new ArrayList<MediaType>();
list.add(MediaType.APPLICATION_JSON);
headers.setAccept(list);
headers.setContentType(MediaType.APPLICATION_JSON);
headers.add("Content-Type", "application/json");
requestEntity = new HttpEntity<Transaction>(t, headers);
ResponseEntity<String> response =
rest.exchange(url, HttpMethod.PUT, requestEntity, MyObject.class);
return response.getStatusCode().getValue();
}
Im getting an HttpClientErrorException: 400 Bad Request
Where is my mistake? What I want is for Spring to automaticly serialize the MyObject. MyObject class is implementing serializable.
What do I miss?
}
Maybe you're doing to much?
Did you try to put the object as json via postman or something similar? If so what is the response?
Nevertheless i created a minimal example for consuming a service via Springs RestTemplate.
This is all needed code for getting a custom object AND putting a custom object via RestTemplate
public void doTransfer(){
String url = "http://localhost:8090/greetings";
RestTemplate restTemplate = new RestTemplate();
ResponseEntity<Greeting> greeting = restTemplate.getForEntity(url, Greeting.class);
LOGGER.info(greeting.getBody().getValue());
Greeting myGreeting = new Greeting();
myGreeting.setValue("Hey ho!");
HttpEntity<Greeting> entity = new HttpEntity<Greeting>(myGreeting);
restTemplate.exchange(url, HttpMethod.PUT, entity, Greeting.class);
}
I've provided a sample project with a sender (maybe not a good name .. it is the project with the greetings endpoint) and a receiver (the project which consumes the greetings endpoint) on Github
Try to do this:
ResponseEntity<MyObject> responseSerialized =
rest.exchange(url, HttpMethod.PUT, requestEntity, MyObject.class);
I am trying to make method Spring MVC method in controller to return text instead of json.
My current method looks like this
#RequestMapping(value = "/upload", method = RequestMethod.POST, produces = "text/html")
public ModelAndView uploadFile(#RequestParam("file") MultipartFile file) {
LOGGER.debug("Attempt to upload file with template.");
try {
String fileContent = FileProcessUtils.processFileUploading(file);
return createSuccessResponse(fileContent);
} catch (UtilityException e) {
LOGGER.error("Failed to process file.", e.getWrappedException());
return createResponse(INTERNAL_ERROR_CODE, e.getMessage());
}
}
But the response header content-type: application/json.
I was trying to pass HttpServletResponse to controller and set content type but it still continued to return json.
What's the problem?
What's FileProcessUtils? Google doesn't bring up anything. Is it a class created by you or your organization? It would appear that the method is returning a response with a content-type of application/json. What were you expecting it to return and why? You would have to somehow parse the json to extract the data necessary for constructing a ModelAndView or find another method that returns what you want.
But without more information on FileProcessUtils, it isn't possible to provide more of an answer.
You can either do this:
#RequestMapping(value = "/foo", method = RequestMethod.GET)
public ResponseEntity foo() throws Exception {
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.TEXT_HTML);
return ResponseEntity.ok().headers(headers).body("response");
}
or do this:
#RequestMapping(value = "/foo", method = RequestMethod.GET, produces = MediaType.TEXT_HTML_VALUE)
Both works fine.
I tried to find how I can write in Spring to POST JSON from REST client. For example, I wrote:
#RequestMapping(value = "/{userId}/add", method = RequestMethod.POST, headers = {"content-type=application/json"})
#ResponseBody
public Map<String, String> saveUser(#RequestBody User user, BindingResult result) {
Map<String, String> jsonResponse = new HashMap<String, String>();
if (result.hasErrors()) {
jsonResponse.put("Message", "Can't add the user");
jsonResponse.put("Code", "401");
return jsonResponse;
}
userService.addUser(user);
jsonResponse.put("Message", "Success add User");
jsonResponse.put("Code", "200");
return jsonResponse;
}
End tested it from Firefox REST client. But I saw 404 error. What am I doing wrong? Thanx for help.
First, if the URI of your request ended with "/user/2/add", it won't map to your method, which is mapped as "/{userId}/add". This will cause the HTTP 404 error you receive. Instead, your URI should end with "/2/add", if the "userId" is 2.
Second, annotating the User parameter with #RequestBody is not enough for the complex User type. You will need to convert your JSON request body into a User object. You can accomplish this with the MappingJacksonHttpMessageConverter. By declaring a bean of this type, you can use Jackson's annotations to control how the JSON is parsed into the User properties.
I am working with Spring MVC using JSON objects. while I am tring to send JSON Object from RESTClient, I am getting
HTTP Status 400 - The request sent by the client was syntactically incorrect ().
This is my controller
ObjectMapper mapper=new ObjectMapper();
#RequestMapping(value = "/addTask", method = RequestMethod.GET)
public ModelAndView addTask(#RequestParam("json") String json) throws JsonParseException, JsonMappingException, IOException
{
System.out.println("Json object from REST : "+json);
Task task=(Task) mapper.readValue(json, Task);
service.addService(task);
return new ModelAndView("Result");
}
My request URL : http://localhost:8080/Prime/addTask
My Json Object :
{"taskName":"nothing","taskId":1234,"taskDesc":"nothing doing"}
Also i tried specifying "Content-Type: application/json" in RESTClient but still am getting the same error
I ran into a similar situation using a JSON string in the request body recently, and using a very similar Spring setup as yours. In my case I wasn't specifying a String parameter and deserialising it myself though, I was letting Spring do that:
#RequestMapping(value = "/myService/{id}", method = RequestMethod.POST)
#ResponseBody
public void myService(#PathVariable(value = "id") Long id, #RequestBody MyJsonValueObject request) {
..
}
I was getting an HTTP error 400 "The request sent by the client was syntactically incorrect" response. Until I realised that there wasn't a default constructor on the #RequestBody MyJsonValueObject so there were problems deserialising it. That problem presented in this way though.
So if you are using POST and objects, and getting errors like this, make sure you have a default constructor! Add some JUnit to be sure you can deserialise that object.
Note: I'm not saying this is the only reason you get this error. The original case used just String (which does have a default constructor !) so it's a little different. But in both cases it appears the request URI appears to have been mapped to the right method, and something has gone wrong trying to extract parameters from the HTTP request.
Try this
Change
#RequestParam("json") String json
To
#RequestBody Task task
If you are not interested in POST method you can try this
change your Controller method from
#RequestMapping(value = "/addTask", method = RequestMethod.GET)
public ModelAndView addTask(#RequestParam("json") String json)
to
#RequestMapping(value = "/addTask/{taskName}/{taskId}/{taskDesc}", method = RequestMethod.GET)
public ModelAndView addTask(#RequestParam("taskName") String taskName,
#RequestParam("taskId") String taskId,#RequestParam("taskDesc") String taskDesc)
and change your URL to
http://localhost:8080/Prime/addTask/mytask/233/testDesc
My problem was due to the incorrect mapping of the #RequestBody object.
My Request Body looks like this
{data: ["1","2","3"]}
I had the following code in my controller
#RequestMapping(value = "/mentee", method = RequestMethod.POST)
public #ResponseBody boolean updateData(#RequestBody List<Integer> objDTO, HttpSession session) {
...
}
This give me HTTP 400 because Spring doesn't know how to bind my Json data to a List.
I changed the RequestBody object to the following
#RequestMapping(value = "/mentee", method = RequestMethod.POST)
public #ResponseBody boolean updateData(#RequestBody ObjectiveDto objDTO, HttpSession session) {
...
}
and defined ObjectiveDto as followed
#ToString
public class ObjectiveDto {
#Getter #Setter
private List<Integer> data;
}
This resolved the HTTP 400 error.