rule

comment text length must be less than 256.

user name length must be less than 256.

page

login.html

user must see login page at first.

• next
  • error
  • chatlist
• template
  • layout ... layout.html
  • content ... login.html

chatlist.html

user success to login, then can see chatlist.

• next
  • some chat
  • error (when chat name too long)
• template
  • layout ... layout.html
  • content ... chatlist.html

somechat.html

in some chat, user can comment.

• next
  • some chat
  • chatlist
  • error (when comment too long)
• template
  • layout ... layout.html
  • content ... somechat.html

error

when something cause error, handle shows error page.

• next
  • login
• template
  • layout ... layout.html
  • content ... error.html

database

use postgresql

table

• chitchatinfo

  • number_of_user
    • int
    • not null
  • number_of_chat
    • int
    • not null

• chatlist

  • create_user_id
    • int
    • not null
  • create_user_name
    • varchar[256]
    • not null
  • create_date
    • date
    • not null
    • ex) '2018-10-01'
  • chat_hash
    • varchar[256]
    • not null
    • primary key
  • chat_name
    • varchat[256]
    • not null
  • number_of_comment
    • int
    • not null

• comments

  • comment_id
    • int
    • not null
    • primary key
  • comment_text
    • varchar[256]
    • not null
  • create_user_id
    • int
    • not null
  • create_user_name
    • varchar[256]
    • not null
  • create_date
    • date
    • not null
  • chat_hash
    • varchar[256]
    • not null

• userinfo

  • user_id
    • int
    • not null
  • user_name
    • varchar[256]
    • not null
  • user_password
    • varchar[256]
    • not null
  • create_date
    • date
    • not null
  • session_state
    • bool
    • not null
  • session_id
    • varchar[256]

function

func sessionCheck() bool

sessionCheck check user session_state is valid, then return bool.

In Handler,

If is valid, Handler check session_id and transfer user to chatlist.

Else, Handler check session_id. If it exist as string, it means that in past session is interrupted.

fucn makeCookie(username string, password string, w http.ResponseWriter)

type http.Cookie struct {

Name: "_cookie",

Value: sessionID,

HttpOnly: true,

}

cookie and session

user have cookie of session_id as random string.

If cookie of session_id user have is same to session_id server have in postgres, user can login automaticaly.

If User don't has Cookie of session_id, there is something wrong, for expample User close browser without doing logout.