Spring MVC Ajax Post 400 Error (Bad Request) - ajax

Question

So I'm using Spring MVC and I'm trying to do an ajax post to add a comment to a Post entity, like a typical social network. And I'm getting an error in the Chrome Developer's Tool's that says this Failed to load resource: the server responded with a status of 400 (Bad Request). I'm thinking that might mean something is going wrong in my controller, however the way this is set up, it's not letting me check it out in debug mode.
I'll show you guys all the pieces of code that work together so you guys can get a better understanding of my problem.
So here's my Ajax, and everything is running through, and sending a "there was an error" message, so It's at least running through the code and reaching the controller.
Also the CDATA stuff is for Thymeleaf.
<script th:inline="javascript">
/*<![CDATA[*/
var postById = /*[[${postById.id}]]*/'1';
var token = $("meta[name='_csrf']").attr("content");
var header = $("meta[name='_csrf_header']").attr("content");
$(document).ajaxSend(function(e, xhr, options) {
xhr.setRequestHeader(header, token);
});
$(document).ready(function(){
$("#submit").on("click", function(ev) {
ev.preventDefault();
$.ajax({
url : "newComment",
type : "post",
data : {
"postById" : postById,
"newComment" : $("#newComment").val()
},
success : function(data) {
console.log(data);
location.reload();
},
error : function() {
console.log("There was an error");
//location.reload();
}
});
});
});
/*]]>*/
</script>
Here's my Controller Get Method
#RequestMapping(value="viewCourse/post/{postId}", method=RequestMethod.GET)
public ModelAndView postViewGet (#RequestParam(value = "pageSize", required = false) Integer pageSize,
#RequestParam(value = "page", required = false) Integer page, #PathVariable Long postId) {
ModelAndView modelAndView = new ModelAndView("post");
{
// Evaluate page size. If requested parameter is null, return initial
// page size
int evalPageSize = pageSize == null ? INITIAL_PAGE_SIZE : pageSize;
// Evaluate page. If requested parameter is null or less than 0 (to
// prevent exception), return initial size. Otherwise, return value of
// param. decreased by 1.
int evalPage = (page == null || page < 1) ? INITIAL_PAGE : page - 1;
//StudySet studySet = studySetRepo.findOne(studySetId);
//List <Row> rows = studySet.getRows();
//Set<Row> rowSet = new TreeSet<Row>(rows);
Post postById = postRepo.findOne(postId);
Comment comment = new Comment();
Page<Comment> postComments = commentService.findByPostOrderByIdDesc((postById), new PageRequest(evalPage, evalPageSize));
Pager pager = new Pager(postComments.getTotalPages(), postComments.getNumber(), BUTTONS_TO_SHOW);
modelAndView.addObject("postId", postId);
modelAndView.addObject("postById", postById);
modelAndView.addObject("postComments", postComments);
modelAndView.addObject("comment", comment);
modelAndView.addObject("selectedPageSize", evalPageSize);
modelAndView.addObject("pageSizes", PAGE_SIZES);
modelAndView.addObject("pager", pager);
return modelAndView;
}
}
Here's my Controller Post Method
#RequestMapping(value="viewCourse/post/newComment", method=RequestMethod.POST)
public #ResponseBody Post newComment (#Valid #RequestParam Long postId, #RequestParam String newComment, ModelMap model, #AuthenticationPrincipal User user)
{
Post post = postRepo.findOne(postId);
Comment comment = new Comment();
comment.setComment(newComment);
comment.setPost(post);
comment.setDate(LocalDate.now());
comment.setTime(LocalTime.now());
comment.setDateTime(LocalDateTime.now());
comment.setUser(user);
user.getComments().add(comment);
post.getComments().add(comment);
commentRepo.save(comment);
Post savedPost = postRepo.save(post);
return savedPost;
}
Also I have some annotations in the entity objects, that could have something to do with it.
Here's my User Entity
#OneToMany(fetch = FetchType.EAGER, cascade = CascadeType.ALL, mappedBy = "user", orphanRemoval = true)
#JsonManagedReference
public Set<Comment> getComments() {
return comments;
}
public void setComments(Set<Comment> comments) {
this.comments = comments;
}
Here's my Comment entity
#ManyToOne
#JsonBackReference
public User getUser() {
return user;
}
public void setUser(User user) {
this.user = user;
}
Also here's a picture of my console in the Chrome Developer Tools, so you guys can see exactly what it's showing me.
If anyone can see where I'm going wrong and point me in the right direction, that would be great, thanks in advance.
Also if you guys need to see any other code, just let me know.

Answer 1

My problem was in the Ajax, I was looking for the postById.id, when I should have been using just the postId that I added to the model in the Get method in the controller.