Session and Cookie
Phan biet session va cookie.
Thuong moi nguoi de nham lan giua 2 khai niem nay. Trong rails tutorial co noi
ve viec luu tru session: session[:user_id] = @user.id
O day ta hieu la id cua @user se duoc luu vao trong session duoi dang 1 hash co key la user_id con key la @user.id. Nhung co 1 van de o day, khi co nhieu nguoi dung cung truy cap 1 luc, thi id
cua nguoi dung nao se duoc luu? Lieu cac key, value do co bi ghi de khog?
- Cookie la mot chuoi cac ki tu da duoc ma hoa, luu lai o trong browser cua nguoi dung.
- Session la 1 trunk cac thong tin, duoc luu tru o tren sever.
Trong lan dau sau khi dang nhap, server se gui cookie ve cho client. Sau do, moi
khi client gui 1 request len server, cookie cung se duoc gui len theo.
Server se dua vao cookie vua duoc gui len de tim dung session cho cookie
do. Tu do, xac dinh duoc user hien tai voi user_id duoc luu trong session.