Pass multiple parameters to rest API - Spring

Question

I am trying to figure out if it is possible to pass a JSON object to rest API, Or pass a multiple parameters to that API ? And how to read these parameters in Spring ? Lets assume that the url looks like the below examples :

Ex.1 http://localhost:8080/api/v1/mno/objectKey?id=1&name=saif

Is it valid to pass a JSON object like in the url below ?

Ex.2 http://localhost:8080/api/v1/mno/objectKey/{"id":1, "name":"Saif"}

Questions:

1) Is it possible to pass a JSON object to the url like in Ex.2?

2) How can we pass and parse the parameters in Ex.1?

I tried to write some methods to achieve my goal, but could not find the right solution?

I tried to pass JSON object as @RequestParam

http://localhost:8080/api/v1/mno/objectKey?id=1 There was an unexpected error (type=Unsupported Media Type, status=415). Content type 'null' not supported

http://localhost:8080/api/v1/mno/objectKey/id=1 There was an unexpected error (type=Not Found, status=404). No message available

http://localhost:8080/api/v1/mno/objectKey/%7B%22id%22:1%7D There was an unexpected error (type=Not Found, status=404). No message available

@RequestMapping(value="mno/{objectKey}",
                method = RequestMethod.GET, 
                consumes="application/json")
    public List<Book> getBook4(@RequestParam ObjectKey objectKey) {
        ...
    }

I tried to pass the JSON object as @PathVariable

@RequestMapping(value="ghi/{objectKey}",method = RequestMethod.GET)
    public List<Book> getBook2(@PathVariable ObjectKey objectKey) {
        ...         
    }

I created this object to hold the id parameter and other parameters like name , etc ....

class ObjectKey{
        long id;
        public long getId() {
            return id;
        }
        public void setId(long id) {
            this.id = id;
        }
    }

Answer 1

Multiple parameters can be given like below,

    @RequestMapping(value = "/mno/{objectKey}", method = RequestMethod.GET, produces = "application/json")
    public List<String> getBook(HttpServletRequest httpServletRequest, @PathVariable(name = "objectKey") String objectKey
      , @RequestParam(value = "id", defaultValue = "false")String id,@RequestParam(value = "name", defaultValue = "false") String name) throws Exception {
               //logic
}

Answer 2

Yes its possible to pass JSON object in URL

queryString = "{\"left\":\"" + params.get("left") + "}";
 httpRestTemplate.exchange(
                    Endpoint + "/A/B?query={queryString}",
                    HttpMethod.GET, entity, z.class, queryString);

Answer 3

(1) Is it possible to pass a JSON object to the url like in Ex.2?

No, because http://localhost:8080/api/v1/mno/objectKey/{"id":1, "name":"Saif"} is not a valid URL.

If you want to do it the RESTful way, use http://localhost:8080/api/v1/mno/objectKey/1/Saif, and defined your method like this:

@RequestMapping(path = "/mno/objectKey/{id}/{name}", method = RequestMethod.GET)
public Book getBook(@PathVariable int id, @PathVariable String name) {
    // code here
}

(2) How can we pass and parse the parameters in Ex.1?

Just add two request parameters, and give the correct path.

@RequestMapping(path = "/mno/objectKey", method = RequestMethod.GET)
public Book getBook(@RequestParam int id, @RequestParam String name) {
    // code here
}

UPDATE (from comment)

What if we have a complicated parameter structure ?

"A": [ {
    "B": 37181,
    "timestamp": 1160100436,
    "categories": [ {
        "categoryID": 2653,
        "timestamp": 1158555774
    }, {
        "categoryID": 4453,
        "timestamp": 1158555774
    } ]
} ]

Send that as a POST with the JSON data in the request body, not in the URL, and specify a content type of application/json.

@RequestMapping(path = "/mno/objectKey", method = RequestMethod.POST, consumes = "application/json")
public Book getBook(@RequestBody ObjectKey objectKey) {
    // code here
}

Answer 4

you can pass multiple params in url like

http://localhost:2000/custom?brand=dell&limit=20&price=20000&sort=asc

and in order to get this query fields , you can use map like

    @RequestMapping(method = RequestMethod.GET, value = "/custom")
    public String controllerMethod(@RequestParam Map<String, String> customQuery) {

        System.out.println("customQuery = brand " + customQuery.containsKey("brand"));
        System.out.println("customQuery = limit " + customQuery.containsKey("limit"));
        System.out.println("customQuery = price " + customQuery.containsKey("price"));
        System.out.println("customQuery = other " + customQuery.containsKey("other"));
        System.out.println("customQuery = sort " + customQuery.containsKey("sort"));

        return customQuery.toString();
    }