<a class="clicklink" href="/bookDetails" book-id="<%= ID =>"><%= title %></a>

<script type="text/javascript">
                      $(document).ready(function(){

                          $(".clicklink").click(function() {
var bookId = $(this).attr("book-id");
// check what you get
console.log("book id : " + bookId);

                            $.ajax({
                              type: 'post',
                              contentType: "application/json; charset=UTF-8",
                              data: JSON.stringify({ID:bookId}),
                              url: 'http://localhost:3000/bookDetails',
                              success: function(data){
                                console.log('success');
                              }
                            });

return false;
                          });
                      });
                  </script>