For some reason I need to call a GET method API and pass json request body for it. I really couldn't find an example for it. I wonder if it is even supported using feign.
How can I do that using feign?
Yes, Feign supports it. You can do the same as with POST requests:
#FeignClient(name = "clientName", url = "http://localhost:8888")
public interface SampleFeignClient {
#GetMapping("/remote")
String test(#RequestBody SampleRequestBody sampleRequestBody);
}
But be aware: a lot of servers ignore body or even refuse that kind of "non-standard" requests completely (GET or HEAD with request bodies).
According to the documentation the correct way to do it would be to use the #SpringQueryMap annotation.
#FeignClient(name = "clientName", url = "http://localhost:8888")
public interface SampleFeignClient {
#GetMapping("/remote")
String test(#SpringQueryMap SampleRequestBody sampleRequestBody);
}
You can find more information here
Related
I have started using WebClient(org.springframework.web.reactive.function.client.WebClient) for calling rest services. I have 2 classes say Utility.java and ServiceImpl.java.
ServiceImpl.java is where I use WebClient. A post call I am making looks like -
ClientResponse response = webClient.post()
.uri(path)
.body(Mono.just(inputDTO),InputDTO.class)
.exchange()
.block();
(ClientResponse above is org.springframework.web.reactive.function.client.ClientResponse)
(I am using exchange instaed of retrive because I want headers as well as status code)
Now trying to convert this response into some DTO - ResponseDTO.
Mono<ResponseEntity<ResponseDTO>> mono = response.toEntity(ResponseDTO.class);
ResponseEntity<ResponseDTO> resEntity = mono.block();
ResponseDTO myObj = resEntity.getBody();
So myObj is an object of ResponseDTO class.
The issue is - when I perform the conversion of 'response into ResponseDTO.java' in my utility class, I get myObj = null. But if I do it in my ServiceImpl.java (just after calling post API), it returns the proper body (ResponseDTO object).
The same issue occurs even if I perform the conversion and post call operation in two different methods in the ServiceImpl.java.
Do I need to configure something here?
I figured out what was the issue.
After calling REST api, body in the response if flushed out after I read it from the response for the first time. I had a Sysout statement in service implementation class where I was reading the body content.
Recommendation: Read the body content only once and store it in a variable. Use it wherever required.
We had a spring web-app that used to handle all front and back end logic. As we need to scale we have split that into two microservices. How would I go about 'forwarding' a post request to another url (including its body and authentication headers). For example:
microservice1 has an endpoint /api/doSomething
microservice2 has an endpoint /privateUrl/doSomething
I want the user to hit the endpoint on microservice1 which will post to microservice2 and return the result.
I have tried with RestTemplate without much luck, i keep getting error "Could not write JSON: No serializer found for class..." from microservice1, i suspect this is because microservice1 doesnt know how to parse the body object microservice2 requires.
microservice1:
#PostMapping("/api/DoSomething")
fun postIT(request: HttpServletRequest, #PathVariable one: String, #PathVariable two: String){ ...}
microservice2:
#CrossOrigin
#PostMapping("/privateUrl/doSomething")
fun postIT(request: HttpServletRequest, #RequestParam one: String, #RequestParam(required = false, defaultValue = "true") two: String,#RequestBody it: IT) { ... }
I know i can parse the entire request in microservice1 and then send it to microservice2, however is there a way to just 'forward' the http request to a new url?
I am not sure what you mean , but if you want to communicate from one server to another you can always use rest template (or any other) and send http request from one service to another, you can see examples here
https://www.tutorialspoint.com/spring_boot/spring_boot_rest_template.htm
https://spring.io/guides/tutorials/bookmarks/
take a look it should work for you.
I have developed Small Spring boot Rest api app. I can able to get the data or create new record and search with paging and sorting.
Now i'm looking for provide input data in body to get the data instead of providing in URL with GET method. Is this method also default function ? Please advise.
public interface CodeTextRepository extends PagingAndSortingRepository<CodeText, Long> {
}
How to write POST method to just get the data ?
http://localhost:8080/api/code
method : POST
{
"code":1
}
If I understand you correctly, you want to create a controller that will get the a model as body parameter ({ "code": 1 }) in a POST method and then do something with it.
To do that, you can create a controller that looks like the following (I inserted pseudo-code as an example):
#RestController
#RequestMapping(value = "/api/code")
public class CodeTextController {
private CodeTextRepository codeTextRepository;
// constructor injection
public CodeTextController(CodeTextRepository codeTextRepository) {
this.codeTextRepository = codeTextRepository;
}
#PostMapping
public CodeText postCodeText(#RequestBody CodeTextRequest codeTextRequest) {
// some code to get from the DB
return codeText;
}
}
public class CodeTextRequest {
private int code;
// getters and setters
}
Simply add Accept header to the request, like
accept: application/json
Spring Data-Rest will return the body after a POST request if either the returnBodyOnCreate flag was explicitly set to true in the RepositoryRestConfiguration OR if the flag was NOT set AND the request has an Accept header.
You can set the flag directly during configuration, or you can set it via the application.properties:
spring.data.rest.returnBodyOnCreate = true
you can also set it separately for update:
spring.data.rest.returnBodyOnUpdate = true
---- edit
Maybe I misunderstood your question. If you simply want to GET an existing data using POST method, then DO NOT DO IT AT ALL! That's not a REST API any more. There must be some reason you want to do it, but you should try do resolve that original problem instead in another way!
I have a controller class with two endpoints
#RestController
#RequestMapping
public class TestController {
#RequestMapping(
value= "/test",
method = RequestMethod.GET)
#ResponseBody
public String getTest() {
return "test without params";
}
#RequestMapping(
value= "/test",
params = {"param"},
method = RequestMethod.GET)
#ResponseBody
public String getTest(#PathParam("param") int param) {
return "test with param";
}
}
One has a parameter, one doesn't, and the both work.
If I use curl or a web browser to hit the endpoints
http://localhost:8081/test
returns
test without params
and
http://localhost:8081/test?param=1
returns
test with param
but the swagger ui only shows the one without a parameter.
If I change the value in the request mapping for the request with a parameter to
#RequestMapping(
value= "/testbyparam",
params = {"param"},
method = RequestMethod.GET)
Swagger UI displays both endpoints correctly, but I'd rather not define my endpoints based on what swagger will or won't display.
Is there any way for me to get swagger ui to properly display endpoints with matching values, but different parameters?
Edit for Clarification:
The endpoints work perfectly fine; /test and /test?param=1 both work perfectly, the issue is that swagger-ui won't display them.
I would like for swagger ui to display the endpoints I have defined, but if it can't, then I'll just have to live with swagger-ui missing some of my endpoints.
Edit with reference:
The people answering here: Proper REST formatted URL with date ranges
explicitly say not to seperate the query string with a slash
They also said "There shouldn't be a slash before the query string."
The issue is in your Request Mapping, The second method declaration is overriding the first method. As Resource Mapping value is same.
Try changing the second method to below. As you want to give input in QueryParam rather than path variable, you should use #RequestParam not #PathParam.
Note that you have to give /test/, In order to tell Spring that your mapping is not ambiguous. Hope it helps.
#RequestMapping(
value= "/test/",
method = RequestMethod.GET)
#ResponseBody
public String getTest (#RequestParam("param") int param) {
return "test with param"+param;
}
Upon reading clarifications, the issue here is that swagger-ui is doing the correct thing.
You have two controller endpoints, but they are for the same RESOURCE /test that takes a set of optional query parameters.
Effectively, all mapped controller endpoints that have the same method (GET) and request mapping (/test) represent a single logical resource. GET operation on the test resource, and a set of optional parameters which may affect the results of invoking that operation.
The fact that you've implemented this as two separate controller endpoints is an implementation detail and does not change the fact that there is a single /test resource that can be operated upon.
What would be the benefit to consumers of your API by listing this as two separate endpoints in swagger UI vs a single endpoint with optional parameters? Perhaps it could constrain the set of allowed valid query parameters (if you set ?foo you MUST set &bar) but this can also be done in descriptive text, and is a much more standard approach. Personally, I am unfamiliar with any publicly documented api that distinguishes multiple operations for the same resource differentiated by query params.
As per Open API Specification 3
OpenAPI defines a unique operation as a combination of a path and an
HTTP method. This means that two GET or two POST methods for the same
path are not allowed – even if they have different parameters
(parameters have no effect on uniqueness).
Reference - https://swagger.io/docs/specification/paths-and-operations/
This was also raised as an issue but it was closed because OAS3 doesn't allow that -
https://github.com/springdoc/springdoc-openapi/issues/859
Try including the param in the path as below.
#GetMapping("/test/{param}")
public String getTest(#PathVariable final int param) {
return "test with param";
}
I'm unclear exactly what you're attempting to do, but I'll give two solutions:
If you want to have PATH parameters e.g. GET /test & GET /test/123 you can do:
#GetMapping("/test")
public String getTest() {
return "test without params";
}
#GetMapping("test/{param}")
public String getTest(#PathVariable("param") int param) {
return "test with param";
}
If you want query parameters (GET /test and GET /test?param=123) then you need a single endpoint that takes an optional parameter:
#GetMapping("test")
public String getTest(#RequestParam("param") Integer param) {
if(param == null) {
return "test without params";
} else {
return "test with param";
}
}
Here is the controller:
Here is the postman:
Via form-data, I can get caseId in my controller.
But raw with header, I can't.
I don't know why... Is there anything wrong with my controller ?
Please help, thanks.
edit 1:
Yeah. Add something more
We know, springMVC will bind data for us, but when we use POST request and put data in body via raw and Content-Type:application/json, spring will still bind data? request.getInputStream() will only call once.
edit 2:
I found a way to get the raw.
get the json string.
edit in 11/29/2017
I found that:
Post with raw, I need to use #RequestBody to recive the value.
Here are the example of how to retrieve data using POSTMAN and bind with SpringMVC
#RequestMapping(value = "/user/", method = RequestMethod.GET)
public ResponseEntity<List<User>> listAllUsers() {
List<User> users = userService.findAllUsers();
if (users.isEmpty()) {
return new ResponseEntity(HttpStatus.NO_CONTENT);
// You many decide to return HttpStatus.NOT_FOUND
}
return new ResponseEntity<List<User>>(users, HttpStatus.OK);
}
You may refer to this article : Spring Boot Rest API Example
Can u bind request param as below and check :
public Object getTcaseByCaseId(#RequestParam("caseId") String caseId) {