Develop Reference

Calling a RESTful service on an external domain via JQuery

I'm trying to calling a Java RESTful service by an html page, but I always get errors like the below:
No 'Access-Control-Allow-Origin' header is present on the requested resource", 405 (Method Not Allowed)
My simplest Java code is:
#SuppressWarnings({ "unchecked", "rawtypes" })
#RequestMapping(value = "/prenotazioni/{id}", method = RequestMethod.POST)
public ResponseEntity<Prenotazione> updatePrenotazione(HttpServletResponse response, #PathVariable int id, #RequestBody Prenotazione obj) {
response.addHeader("Access-Control-Allow-Origin", "*");
response.addHeader("Access-Control-Allow-Methods", "GET,PUT,POST,DELETE");
response.addHeader("Access-Control-Allow-Headers", "Content-Type");
try {
prenotazioneService.updatePrenotazione(id, obj);
} catch (Exception e) {
return new ResponseEntity(e.getMessage(), HttpStatus.BAD_REQUEST);
}
return new ResponseEntity<Prenotazione>(obj,HttpStatus.OK);
}
And the html code is:
$('#btnSalva').on('click', function(e){
//Creo la stringa JSON nel formato atteso dal servizio RESTful
var obj = '{"aula":{"id":' + $("#id_aula").val() + '},"id_utente":1,"data_inizio":"' + $("#datetimepicker1").data().DateTimePicker.date() + '","data_fine":"' + $("#datetimepicker2").data().DateTimePicker.date() + '"}';
var id = $("#id_evento").val();
var url = "http://localhost:8080/gestione_aule/prenotazioni/" + id;
//With $.post I've got error: No 'Access-Control-Allow-Origin
$.post( "http://localhost:8080/gestione_aule/prenotazioni/" + id, obj );
//With $.ajax I've got error: 405 (Method Not Allowed)
/*$.ajax({
url: "http://localhost:8080/gestione_aule/prenotazioni/" + id,
type: "POST",
crossDomain: true,
data: obj,
dataType: "jsonp",
success:function(result){
alert(JSON.stringify(result));
},
error:function(xhr,status,error){
alert(status);
}
});*/
/*$.postJSON = function(url, data, callback) {
return jQuery.ajax({
headers: {
'Accept': 'application/json',
'Content-Type': 'application/json'
},
'type': 'get',
'url': url,
'data': JSON.stringify(data),
'dataType': 'jsonp',
'complete': function(e){
alert("c " + e);
},
'success': function(e){
alert("s " + e);
},
'error': function(e){
alert("e " + e);
}
});
};
$.postJSON(url, obj, function(e){alert(e);});*/
});
I've tried:
with and without specify response header in java servlet
mapping PUT and POST method
using $.post $.ajax
setting dataType json and jsonp
and many other combinations :)
But anyone worked for me... any suggest please?
Note: as I wrote in the code with $.post I've got error: No 'Access-Control-Allow-Origin, with ajax I've got error: 405 (Method Not Allowed)
Thans

The problem here that CORS (cross domain support) has 2 types of request:
Simple - such as HEAD, GET and POST. POST with content-type: application/x-www-form-urlencoded, multipart/form-data or text/plain
The rest requests are called Preflight requests
Your CORS request is a Preflight one. In Preflight requests the browser fires 2 requests:
OPTIONS - asking the server to verify that the origin, method and additional headers are trusted
The actual request - in your case POST
To fix the issue your case, add a new mapping that will handle the OPTIONS request:
#RequestMapping(value = "/prenotazioni/{id}", method = RequestMethod.OPTIONS)
public void updatePrenotazione(HttpServletResponse response, #PathVariable int id) {
response.addHeader("Access-Control-Allow-Origin", "*");
response.addHeader("Access-Control-Allow-Methods", "GET,PUT,POST,DELETE");
response.addHeader("Access-Control-Allow-Headers", "accept, content-Type");
}

Undefined Javascript Error When AJAX Call Fails

I have a Spring MVC controller being called by AJAX and returns JSON. If the call succeeds without error, I am returning a string message with the key "message". Likewise, if an exception is caught, I return a string error also with the key "message". I also return a HTTP error response.
In my Javascript, I output this "message" in an alert. The alert displays the message in the event of a successful call. If the call is unsuccessful, I get a Javascript error that "data is undefined".
Why is "data" accessible when successful but not when the call fails, and what correction do I need to make this work?
I am a newbie to AJAX calls with Spring so any general feedback/critique of my solution below is welcome and appreciated.
N.B. The alerts in the Javascript and the messages themselves are dummy implementations until I correctly provide user feedback by modifying the DOM.
The Controller
#RequestMapping(value = "/getMovieData", method = RequestMethod.POST, produces = "application/json")
#ResponseBody
public Map<String, Object> getMovieData(#RequestBody Map<String, Object> json, HttpServletResponse response) {
String movieId = json.get("id").toString();
Map<String, Object> rval = new HashMap<String, Object>();
try {
Movie movie = movieService.getMovieData(movieId);
rval.put("message", "You have succeeded");
rval.put("movie", movie);
} catch (Exception e) {
response.setStatus(HttpServletResponse.SC_BAD_REQUEST);
rval.put("message", "You have an error - " + e.getMessage());
}
return rval;
}
The Javascipt
function getMovieData(data) {
var request = $.ajax({
type : 'POST',
url : '<c:url value="/getMovieData" />',
dataType : "json",
contentType : "application/json; charset=utf-8",
data : data,
});
request.done(function(data) {
alert("Success: " + data.message);
populateMovieFields(data.movie);
});
request.fail(function(xhr, status, error, data) {
alert("status: " + status);
alert("error: " + error);
alert("Fail: " + data.message);
});
}

The JSON response is available inside the jqXHR object passed as the first parameter.
request.fail(function(jqXHR, textStatus, errorThrown) {
alert("Fail: " + jqXHR.responseJSON.message);
});

Pass an ID to frontend from the server

I am building a web app and I need to pass the user's id to my front-end(angular) so I can do some ajax calls.
My question is, how can I give(store) the user's id to my front end? For example, a user can create a group by specifying a group name, but I need to be able to pass the users Id aswell in my ajax request(My backend endpoint needs both an Id and a name).
Angular:
$scope.createGroup = function() {
$http.post(BASE_URL + "/group", $scope.groupRequest).
success(function (data, status, headers, config) {
console.log("Success");
}).error(function(data, status, headers, config) {
$log.info("Error: status =" + status + ", body =" + JSON.stringify(data));
});
}
Front-end controller
#RequestMapping(value = "/group", method = RequestMethod.POST)
public ResponseEntity createGroup(#RequestBody Map body) {
try {
return restTemplate.postForEntity(URI.create(BASE_URL + "/group"), body, Map.class);
} catch (HttpClientErrorException e) {
LOG.warn("Error when trying to fetch groups", e);
return ResponseEntity.badRequest().body(e.getResponseBodyAsString());
}
}
Java Back end controller
#RequestMapping(value = "/group", method = RequestMethod.POST)
public ResponseEntity createGroup(#RequestBody #Valid GroupRequest groupRequest, BindingResult validation) {
if (validation.hasErrors()) {
throw new ValidationException(validation.getFieldErrors());
}
Long groupId = groupService.createGroup(groupRequest);
URI groupLocationURI = URI.create("/group/" + groupId);
return ResponseEntity.created(groupLocationURI).build();
}
Thanks

Multipart request giving issues when received in rest service

I am trying to upload a file using multipart request through angularjs and receive the content on my Rest service. I am putting up this question here after trying several helps for last 4 days and tiring myself to utmost level. I would appreciate if you can fine tune my approach or suggest another approach (I am open to any suggestions which may work as I am out of ideas now).
Just a pointer, I have tried writing a servlet to read the multipart request sent through angularjs and I got the parts correctly. But I am still putting the angular code here for your reference as I am not better on both angular and rest.
Following is the html extract for file upload:
<div>
<input type="file" data-file-upload multiple/>
<ul>
<li data-ng-repeat="file in files">{{file.name}}</li>
</ul>
</div>
Followingis the angularjs directive code extract:
.directive('fileUpload', function () {
return {
scope: true, //create a new scope
link: function (scope, el, attrs) {
el.bind('change', function (event) {
var files = event.target.files;
//iterate files since 'multiple' may be specified on the element
for (var i = 0;i<files.length;i++) {
//emit event upward
scope.$emit("fileSelected", { file: files[i] });
}
});
}
};
})
Following is the angularjs controller code extract
//a simple model to bind to and send to the server
$scope.model = {
name: "test",
comments: "TC"
};
//an array of files selected
$scope.files = [];
//listen for the file selected event
$scope.$on("fileSelected", function (event, args) {
$scope.$apply(function () {
//add the file object to the scope's files collection
$scope.files.push(args.file);
});
});
//the save method
$scope.save = function() {
$http({
method: 'POST',
url: "/services/testApp/settings/api/vsp/save",
headers: { 'Content-Type': undefined },
transformRequest: function (data) {
var formData = new FormData();
formData.append("model", angular.toJson(data.model));
for (var i = 0; i < data.files.length; i++) {
formData.append("file" , data.files[i]);
}
return formData;
},
data: { model: $scope.model, files: $scope.files }
}).
success(function (data, status, headers, config) {
alert("success!");
}).
error(function (data, status, headers, config) {
alert("failed!");
});
};
And here is my rest service code:
#Path("/vsp")
public class SampleService{
#Path("/save")
#POST
#Consumes(MediaType.MULTIPART_FORM_DATA)
public void saveProfile(#FormParam("model") String theXml,
#FormParam("file") List<File> files) throws ServletException, IOException {
final String response = "theXML: " + theXml + " and " + files.size() + " file(s) received";
System.out.println(response);
}
}
And here is the response:
theXML: {"name":"test","comments":"TC"} and 1 file(s) received
The problem is that the content of the file is coming in path and I am not able to get the input stream to read the file. I even tried using
new ByteArrayInputStream(files.get(0).getPath().getBytes())
If the content is text (like txt or csv) it works, but if the content is any other file like xls etc, the retrieved content is corrupt and unusable. Also tried using Jeresy api, but with same result. Am I missing anything obvious? Any help is appreciated.

I came across a few links, but none worked for me. So finally, I had to write a servlet to read the multipart request and added the files and the request parameters as request attributes. Once the request attributes are set, I forwarded the request to my Rest service.
Just for the record, if the multipart request is read once to extract the parts, the request will not have the parts in the forwarded servlet. So I had to set them as request attributes before forwarding.
Here is the servlet code:
public class UploadServlet extends HttpServlet {
#Override
protected void doPost(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
// process only if its multipart content
RequestContext reqContext = new ServletRequestContext(request);
if (ServletFileUpload.isMultipartContent(reqContext)) {
try {
List<FileItem> multiparts = new ServletFileUpload(
new DiskFileItemFactory()).parseRequest(request);
ArrayList<FileItem> fileList = new ArrayList<FileItem>();
request.setAttribute("files", fileList);
for (FileItem item : multiparts) {
if (!item.isFormField()) {
fileList.add(item);
} else {
request.setAttribute(item.getFieldName(),
item.getString());
}
}
request.setAttribute("message", "success");
} catch (Exception ex) {
request.setAttribute("message", "fail"
+ ex);
}
} else {
request.setAttribute("message",
"notMultipart");
}
System.out.println(request.getRequestURI().substring(request.getRequestURI().indexOf("upload")+6));
String forwardUri = "/api" + request.getRequestURI().substring(request.getRequestURI().indexOf("upload")+6);
request.getRequestDispatcher(forwardUri)
.forward(request, response);
}
}
Any request starting with /upload/<rest api path> will be received by the servlet and once the attributes are set, they will be forwarded to /api/<rest api path>.
In the rest api, I used the following code to retrieve the parameters.
#Path("/vsp")
public class SampleService{
#Path("/save")
#POST
#Consumes(MediaType.MULTIPART_FORM_DATA)
public void saveProfile(#Context HttpServletRequest request,
#Context HttpServletResponse response) throws Exception {
// getting the uploaded files
ArrayList<FileItem> items = (ArrayList<FileItem>)request.getAttribute("files");
FileItem item = items.get(0);
String name = new File(item.getName()).getName();
item.write( new File("C:" + File.separator + name));
// getting the data
String modelString = (String)request.getAttribute("model");
// Getting JSON from model string
JSONObject obj = JSONObject.parse(modelString);
String responseString = "model.name: " + obj.get("name") + " and " + items.size() + " file(s) received";
System.out.println(responseString);
}
}

JQuery Ajax Requests behaving unexpectedly

I am using Jquerys Ajax method to talk to my web service. The code seems OK, but I just monitored HTTP traffic using HTTPFox firefox plugin and I noticed unexpected results. To begin with, I am setting the ContentType as application/json and my web service is also producing JSON data but HTTPFox indicates Content Type for my HTTP requests as application/vnd.sun.wadl+xml (NS_ERROR_DOM_BAD_URI).
The Request Method is GET as set in my Ajax request, but HTTPFox indicates my Request method as OPTIONS. And while the Request succeeds and data is returned, the onSuccess method of my Ajax request is not called. Instead, the onError method is called. HTTP Fox is able to capture the data from my web service as response. See the image for HTTP Fox.
Finally, all other request from other processes in my browser seem OK but my HTTP requests are flagged 'RED' by HTTP Fox. The request from other pages and processes seem OK.( GREEN or WHITE).
I have attached screenshot of HTTPFox highlighted on one of my Request. The flagged ones are also from my application.
Image:
I have also pasted the Ajax code I am using to make the HTTP Requests.
window.onload = function() {
var seq_no = getParameterByName("seq_no");
var mileage = getParameterByName("mileage");
document.getElementById("seq_no").value = seq_no;
document.getElementById("mileage").value = mileage;
var param = 'vehReg='+encodeURIComponent(document.getElementById('vehReg').value);
// alert(param);
loadVehicleInfo(param);
};
function loadVehicleInfo(params) {
$("#message").html('<p><font color="green">Loading...</font></p>');
$.ajax({
type: "GET",
url: "http://localhost:8080/stockcloud/rest/vehicles/info",
data: params,
contentType: "application/json; charset=utf-8",
dataType: "json",
success:
function(data,status) {
$("#message").empty();
$("#message").html('<p>'+getAsUriParameters(data)+'</p>');
},
error :
function(XMLHttpRequest, textStatus, errorThrown) {
$("#message").html("<p> <font color='red'>The following error occurred: " +textStatus+ ': '+errorThrown+ "</font>");
}
});
};
function getAsUriParameters (data) {
return Object.keys(data).map(function (k) {
if (_.isArray(data[k])) {
var keyE = encodeURIComponent(k + '[]');
return data[k].map(function (subData) {
return keyE + '=' + encodeURIComponent(subData);
}).join('&');
} else {
return encodeURIComponent(k) + '=' + encodeURIComponent(data[k]);
}
}).join('&');
};
function getParameterByName(name) {
name = name.replace(/[\[]/, "\\[").replace(/[\]]/, "\\]");
var regex = new RegExp("[\\?&]" + name + "=([^&#]*)"),
results = regex.exec(location.search);
return results == null ? "" : decodeURIComponent(results[1].replace(/\+/g, " "));
}
Server side Code for the request:
#Path("/vehicles")
public class VehiclesService {
#GET
#Path("info")
#Produces("application/json")
public Response getVehicleInfo(#DefaultValue("__DEFAULT__") #QueryParam("vehReg") String vehReg) {
// Send SOAP Message to SOAP Server
ServerResponse resp = new ServerResponse();
if("__DEFAULT__".equals(vehReg)) {
resp.setError("Vehicle registration must be supplied as a query parameter: ?vehReg=<THE REG NO>");
resp.setResult(false);
Response.status(Response.Status.BAD_REQUEST).entity(resp).build();
}
try {
// actual code to return the car info and return XML string with the info.
connection.disconnect();
String xml = URLDecoder.decode(s.toString(),"UTF-8");
xml = xml.replace("<", "<").replace(">", ">").replace("<?xml version='1.0' standalone='yes' ?>", "");
System.out.println(xml);
resp.setVehicle(new VehicleParse().parse(xml));
resp.setResult(true);
} catch(Exception e) {
resp.setResult(false);
resp.setError(e.getMessage());
e.printStackTrace();
Response.status(Response.Status.INTERNAL_SERVER_ERROR).entity(resp).build();
}
return Response.status(Response.Status.OK).entity(resp).build();
}
}
Is there something I am not doing right?
Thanks.