Spring MVC controller - getPathInfo() is null - spring-mvc

I have worked servlet that need to convert to Spring MVC controller to have access spring beans etc. Why in normal servlet request.getPathInfo() return not null, but in Spring Controller i get null value ? I know i can use #PathVariable, but wonder why the results of this method is the difference?
#RequestMapping(value = {"/test", "/test/*"})
public void test(HttpServletRequest req, HttpServletResponse res) {
log.info(req.getPathInfo() == null); // true!
if (req.getMethod().equalsIgnoreCase("get")) {
// analogue to doGet...
} else {
// analogue to doPost...
}
}

I think the solution is in the javadoc of getPathInfo()
The extra path information follows the servlet path but precedes the
query string and will start with a "/" character.
In case of Spring the servlet path is the full path hence if you call getServletPath() it will always return the full URI and getPathInfo() will return nothing.

Related

Spring Boot - MockMVC forwardedUrl using Thymeleaf

I have a basic SpringBoot app. using Spring Initializer, embedded Tomcat, Thymeleaf template engine, and package as an executable JAR file.
I have this controller:
#Controller
#RequestMapping("/deviceevent")
public class DeviceEventController {
#RequestMapping(value={ "/list"}, method = { RequestMethod.GET})
public String deviceeventList() {
return "tdk/deviceEvent/DeviceEventList";
}
}
and this other test class. Tests using Spring's MockMVC framework. This drives an MVC application in a test, as if it was running in a container,
#RunWith(SpringJUnit4ClassRunner.class)
#WebAppConfiguration
#WebMvcTest
public class MockMvcTests {
// Pull in the application context created by #ContextConfiguration
#Autowired
private WebApplicationContext wac;
private MockMvc mockMvc;
#Before
public void setup() {
// Setup MockMVC to use our Spring Configuration
this.mockMvc = MockMvcBuilders.webAppContextSetup(this.wac).build();
}
#Test
public void getDeviceEventsTest() throws Exception {
this.mockMvc
.perform(get("/deviceevent/list") //
.accept(MediaType.parseMediaType("text/html;charset=UTF-8")))
.andExpect(status().isOk()) //
.andExpect(model().size(1)) //
.andExpect(forwardedUrl("tdk/deviceEvent/DeviceEventList"));
}
But I got this error in the forwarded URL. I always used this method in JSP, never in Thymeleaf, but I guess that It is the same:
java.lang.AssertionError: Forwarded URL expected:</tdk/deviceEvent/DeviceEventList> but was:<null>
Assuming a standard Thymeleaf/Spring setup, it looks like there is a misunderstanding with what the controller is doing - when the controller returns that string "tdk/deviceEvent/DeviceEventList" it is not forwarding the HTTP request somewhere, but returning a view name.
With a normal Spring-thymeleaf setup, that string corresponds to the name of a thymeleaf view that will be rendered on hitting that endpoint (I assume the controller is just serving a normal webpage - so that path probably corresponds to some file path most likely in src/main/resources - but again, this depends a lot on your spring config) - at this point the HTTP request has not been returned to the user, and Spring is still processing it - and will attempt to render the HTML view before returning to the user.
The forwarded URL is used if Spring is not rendering anything but instead returning a HTTP response to the user to forward them to another URL (which will start a different Spring request-response process) using a 301/302 mechanism.
Note the difference in the following methods:
#RequestMapping( value="/document", method=RequestMethod.GET )
public String newDocumentSettings( Model model ){
model.addAllAttributes( contentManagementService.documentToJson() );
return "pages/document-settings";
}
#RequestMapping( value="/document", method=RequestMethod.POST )
public String createNewDocument( #RequestParam String title, #RequestParam String overview, #RequestParam String tags ){
Document doc = documentService.createDocument( title, overview, tags );
return "redirect:/document/${doc.url}/1?getting-started";
}
The first renders the template at the given filepath, the second returns a redirect command to the browser to make another HTTP request to the given URL.
In any case, the forwardedUrl in your test case is because hte HTTP Response doesn't have a URL to forward to (because its returning the HTML). If you do want forwarding behaviour (e.g. you actually want to complete the response and the browser to make a second HTTP request) then you would likely need to update the controller as per example, however, if you are happy with the rendered html page, then the test is invalid (look at the Thymeleaf testing framework to see how to test templating).
Caveat: This is based on the assumption of default Spring-Boot config - if you have other config whereby that string does result in a forwarded HTTP request then this doesnt apply!
Taking a guess here, but the URL tdk/deviceEvent/DeviceEventList is probably not defined. Try replacing it with the URL associated with your context (edit as necessary):
#Test
public void getDeviceEventsTest() throws Exception {
this.mockMvc
.perform(get("/deviceevent/list")
.accept(MediaType.parseMediaType("text/html;charset=UTF-8")))
.andExpect(status().isOk())
.andExpect(model().size(1))
.andExpect(forwardedUrl("/WEB-INF/tdk/deviceEvent/DeviceEventList.html"));
}
Aside, instead of:
#RequestMapping(value={ "/list"}, method = { RequestMethod.GET})
you can use the shorthand:
#GetMapping("/list")

Forward request to spring controller

From a servlet , I am forwarding the request to a spring controller like below
RequestDispatcher rd = request.getRequestDispatcher("/myController/test?reqParam=value");
rd.forward(request, response);
In order to pass a parameter to the spring controller , I am passing it as request parameter in the forward URL.
Is there a better way of doing this ?
Instead of passing in request parameter , can I pass as a method parameter to the spring controller during forward ?
This will be called when /myController/test?reqParam=value is requested:
#RequestMapping("/myController/test")
public String myMethod(#RequestParam("reqParam") String reqParamValue) {
return "forward:/someOtherUrl?reqParam="+reqParamValue; //forward request to another controller with the param and value
}
Or you can alternatively do:
#RequestMapping("/myController/test")
public String myMethod(#RequestParam("reqParam") String reqParamValue,
HttpServletRequest request) {
request.setAttribute("reqParam", reqParamValue);
return "forward:/someOtherUrl";
}
you can use path variable such as follow without need to use query string parameter:
#RequestMapping(value="/mapping/parameter/{reqParam}", method=RequestMethod.GET)
public #ResponseBody String byParameter(#PathVariable String reqParam) {
//Perform logic with reqParam
}

Spring MVC optionally returning no view in a single mapping

I have a case where i need to :
Return a 304 not modified status if the blog hasnt been modified
Or return the blog view if it's been modified since If-Modified-Since request header
The problem is when i want to return 304 status, how do i tell spring mvc not to assume another view from the null return, and start sending the response with the status immediately ?
#RequestMapping(value={"/blogs/{blogId}"}, method=RequestMethod.GET)
public String hello(final HttpServletRequest req, final HttpServletResponse resp, final Model model,
#PathVariable("blogId") final String blogId) {
if (isModified(req, blogId)) {
resp.setStatus(HttpServletResponse.SC_NOT_MODIFIED);
return null; // this doesnt stop spring mvc to assume a view name
}
populate(model, grabBlog(blogId));
return "blog";
}
From the HTTP perspective returning a view doesn't make sense at all. The Spring documentation covers that use case:
#RequestMapping
public String myHandleMethod(WebRequest webRequest, Model model) {
long lastModified = // 1. application-specific calculation
if (request.checkNotModified(lastModified)) {
// 2. shortcut exit - no further processing necessary
return null;
}
// 3. or otherwise further request processing, actually preparing content
model.addAttribute(...);
return "myViewName";
}
There are two key elements to note: calling request.checkNotModified(lastModified) and returning null. The former sets the response status to 304 before it returns true. The latter, in combination with the former, causes Spring MVC to do no further processing of the request.
You can create an exception with the appropriate annotation and then throw it. Spring will then generate a page for that error code.
From: http://spring.io/blog/2013/11/01/exception-handling-in-spring-mvc
#ResponseStatus(value=HttpStatus.NOT_FOUND, reason="No such Order") // 404
public class OrderNotFoundException extends RuntimeException {
// ...
}

Angularjs - Spring MVC integration

I am trying to integrate AngularJS with Spring MVC; but I am not able to post parameters to spring controller as RequestBody. Can some one help me to achieve the same. Below is brief flow of my program.
After doing data entry TodoNewController gets executed. From here I am calling user-defined method "create" which I have defined in services.js. As per the flow after this it should call create method of TodoController.java along with input params; but it is not happening. Can some one let me know what is wrong with the code. Below is the code for same.
controller.js
function TodoNewController($scope, $location, Todo) {
$scope.submit = function () {
Todo.create($scope.todo, function (todo) {
$location.path('/');
});
};
$scope.gotoTodoListPage = function () {
$location.path("/")
};
}
services.js
angular.module('todoService', ['ngResource']).
factory('Todo', function ($resource) {
return $resource('rest/todo/:id', {}, {
'create': {method:'PUT'}
});
});
TodoController.java
#Controller
public class TodoController {
private static final AtomicLong todoIdGenerator = new AtomicLong(0);
private static final ConcurrentSkipListMap<Long, Todo> todoRepository = new ConcurrentSkipListMap<Long, Todo>();
#RequestMapping(value = "/todo", method = RequestMethod.PUT)
#ResponseStatus(HttpStatus.NO_CONTENT)
public void create(#RequestBody Todo todo) {
long id = todoIdGenerator.incrementAndGet();
todo.setId(id);
todoRepository.put(id, todo);
}
}
Spring expects application/x-www-form-urlencoded as the Content-Type of the request. You may try inject $http into your service and invoke $http.defaults.headers.put["Content-Type"] = "application/x-www-form-urlencoded"; at the beginning of it.
Modify the request mapping to match the actual mapping /rest/todo and change the databinding to use #ModelAttribute.
#RequestMapping(value = "/rest/todo", method = RequestMethod.PUT)
#ResponseStatus(HttpStatus.NO_CONTENT)
public void create(#ModelAttribute Todo todo) {
long id = todoIdGenerator.incrementAndGet();
todo.setId(id);
todoRepository.put(id, todo);
}
Isolate the problem first. Is it Spring or Angular that's causing the issue? I suggest you install a Rest client plugin either in Chrome or FireFox. Then create a PUT request and enter the correct endpoint URL. If you're able to receive the correct response, then it means your Angular request is constructed incorrectly.
Now, run your Angular-based client. Make a PUT request. Inspect the parameters and request sent (in Chrome, you can use Developer tools) and see if it matches the request you sent earlier. If it does, then it should work. If not, then you know the problem.
Also, your Angular resource:
$resource('rest/todo/:id')
has a different URL than what you have in your Spring controller
#RequestMapping(value = "/todo", method = RequestMethod.PUT)
So the first one is like 'rest/todo/1' and the latter is '/todo'. I don't think those would match.

ASP.NET MVC 2.0 JsonRequestBehavior Global Setting

ASP.NET MVC 2.0 will now, by default, throw an exception when an action attempts to return JSON in response to a GET request. I know this can be overridden on a method by method basis by using JsonRequestBehavior.AllowGet, but is it possible to set on a controller or higher basis (possibly the web.config)?
Update: Per Levi's comment, this is what I ended up using-
protected override JsonResult Json(object data, string contentType, System.Text.Encoding contentEncoding)
{
return Json(data, contentType, JsonRequestBehavior.AllowGet);
}
This, like other MVC-specific settings, is not settable via Web.config. But you have two options:
Override the Controller.Json(object, string, Encoding) overload to call Json(object, string, Encoding, JsonRequestBehavior), passing JsonRequestBehavior.AllowGet as the last argument. If you want this to apply to all controllers, then do this inside an abstract base controller class, then have all your controllers subclass that abstract class.
Make an extension method MyJson(this Controller, ...) which creates a JsonResult and sets the appropriate properties, then call it from your controller via this.MyJson(...).
There's another option. Use Action Filters.
Create a new ActionFilterAttribute, apply it to your controller or a specific action (depending on your needs). This should suffice:
public class JsonRequestBehaviorAttribute : ActionFilterAttribute
{
private JsonRequestBehavior Behavior { get; set; }
public JsonRequestBehaviorAttribute()
{
Behavior = JsonRequestBehavior.AllowGet;
}
public override void OnResultExecuting(ResultExecutingContext filterContext)
{
var result = filterContext.Result as JsonResult;
if (result != null)
{
result.JsonRequestBehavior = Behavior;
}
}
}
Then apply it like this:
[JsonRequestBehavior]
public class Upload2Controller : Controller
MVC 2 block Json for GET requests for security reasons. If you want to override that behavior, check out the overload for Json that accepts a JsonRequestBehavior parameter.
public ActionResult Index()
{
return Json(data, JsonRequestBehavior.AllowGet)
}
I also got this error when I first use MVC 2.0 using my old code in MVC 1.0. I use fiddler to identify the cause of the error. See the steps on how to troubleshoot it using Fidder -
http://www.rodcerrada.com/post/2011/07/11/jQuery-getJSON()-does-not-tirgger-the-callback-in-ASPNET-MVC-2.aspx
Is this is the security issue MVC2 was trying to address?
http://haacked.com/archive/2009/06/25/json-hijacking.aspx
If so, it seems like the vulnerability is only an issue if you are trying to do a json call to an outside website. If your MVC2 app is only making json calls to your own website (to fill jqgrids for example), shouldn't you be able to safely override the Json call in your base controller to always allow get?
Just change JSON code from :
$.getJson("methodname/" + ID, null, function (data, textStatus)
to:
$.post("methodname/" + ID, null, function (data, textStatus)

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