angularjs and grails 2.5.0 save success, no errors but not saving to database - angularjs

Question

I've been looking for similar situations like mine has and I've seen that it is common to have this error but I can not find the right solution with my problem. I would really appreciate any help.
My problem right now is that when I execute this it return and HTTP 200 and also prints a line on my terminal which confirms me that it creates the JSON file. There are no errors but when I checked on my database, there's nothing in it.
What I've tried so far:
newBook.save(flush: true)
edit my datasource from create-drop to update (but my whole database disappears so I returned the data. I only need to save it during a demo so I understand that the data will be lost every time the application restarts)
Postman GET and POST
GET: 200 OK
POST: 200 OK
but when I GET again, nothing is showing
debugging using console and println (but there might be something that I missed since I'm just starting to learn both AngularJS and Grails)
I am hoping that these data can give a detailed information about my problem, I am open for any questions.
Here are my sample codes:
back-end codes: Grails 2.5.0
Domain class
class Book {
String name
int page
boolean new
static belongsTo = [student: student]
static constraints = {
}
}
Controller
import grails.converters.JSON
import org.springframework.security.access.annotation.Secured
#Secured('permitAll')
class BookController {
def index() {
render Book.list() as JSON
}
def save() {
def newBook = new Book(request.JSON)
newBook.save(flush: true)
println request.JSON
render(['success': true] as JSON)
}
def show() {
def Book = Book.get(params.id)
render Book as JSON
}
}
front-end codes: AngularJS
Controller
app.controller('Book', function($scope, store, $state, bookFactory){
$scope.book = {}
$scope.saveBook = function() {
$scope.book.assessment = $scope.getBook();
console.log($scope.book);
bookFactory.save($scope.book,function (result){
console.log(result)
}, function (error) {
console.log(error)
})
}
$scope.getBook = function() {
var result = "";
if ($scope.book.page > 10){
result = "many pages";
}else if ($scope.book.new && $scope.book.page > 20){
result = "new and many pages";
}else {
result = "old book";
}
return result;
};
})
Service
app.factory('bookFactory', ['$resource', function ($resource) {
return $resource('api/book',
{
'update': {method: 'PUT'}
})
}])
app.js
.state("book", {
url: "/book",
templateUrl: "assets/app/partials/book.html",
controller: 'Book',
data: {
requiresLogin: true
}
})
HTML
Book Name:
<input type="text" ng-model="book.name" name="bookName" required="" class="form-control" />
Number of Pages:
<input type="number" ng-model="book.page" name="numberPage" required="" class="form-control" placeholder="Number of Pages"/>
Bought within the last 30 days?
<div class="form-group">
<div class="radio">
<label>
<input type="radio" name="new" value=true ng-model="book.new" >
<font color=green>YES</font>
</label>
</div>
<div class="radio">
<label>
<input type="radio" name="new" value=false ng-model="book.new">
<font color=red>NO</font>
</label>
</div>
</div>
<a ui-sref="book" class="btn btn-primary" name="bookBtn" ng-click="saveBook()"> Next </a>