python - flask-login not sure how to make it work using sqlite3 -

so far made user object , login function, don't understand user_loader part @ all. confused, here code, please point me in right direction.

@app.route('/login', methods=['get','post']) def login():     form = login()     if form.validate():         user=request.form['name']         passw=request.form['password']          c = g.db.execute("select username users username = (?)", [user])         userexists = c.fetchone()         if userexists:             c = g.db.execute("select password users password = (?)", [passw])             passwcorrect = c.fetchone()             if passwcorrect:                 #session['logged_in']=true                 #login_user(user)                 flash("logged in")                 return redirect(url_for('home'))             else:                 return 'incorrecg pw'         else:             return 'fail'     return render_template('login.html', form=form)  @app.route('/logout') def logout():     logout_user()     return redirect(url_for('home')) 

my user

class user():      def __init__(self,name,email,password, active = true):         self.name = name         self.email = email         self.password = password         self.active = active      def is_authenticated():         return true         #return true if user authenticated, provided credentials      def is_active():         return true         #return true if user activte , authenticated      def is_annonymous():         return false         #return true if annon, actual user return false      def get_id():         return unicode(self.id)         #return unicode id user, , used load user user_loader callback      def __repr__(self):         return '<user %r>' % (self.email)      def add(self):         c = g.db.execute('insert users(username,email,password)values(?,?,?)',[self.name,self.email,self.password])         g.db.commit() 

my database

import sqlite3 import sys import datetime  conn = sqlite3.connect('data.db')#create db  conn:     cur = conn.cursor()     cur.execute('pragma foreign_keys = on')     cur.execute("drop table if exists posts")     cur.execute("drop table if exists users")     cur.execute("create table users(id integer primary key, username text, password text, email text)")     cur.execute("create table posts(id integer primary key, body text, user_id int, foreign key(user_id) references users(id))") 

i set loginmanager in init. not sure next, know have how set

@login_manager.user_loader def load_user(id):     return user.query.get(id) 

how adjust portion code work database?

edit: please let me know if looks correct or can improved :)

 @login_manager.user_loader     def load_user(id):         c = g.db.execute("select id users username = (?)", [id])         userid = c.fetchone()         return userid      @app.route('/login', methods=['get','post'])     def login():         form = login()         if form.validate():             g.user=request.form['name']             g.passw=request.form['password']              c = g.db.execute("select username users username = (?)", [g.user])             userexists = c.fetchone()             if userexists:                 c = g.db.execute("select password users password = (?)", [g.passw])                 passwcorrect = c.fetchone()                 if passwcorrect:                   user = user(g.user, 'email', g.passw)                 login_user(user)                 flash("logged in")                               return redirect(url_for('home'))             else:                 return 'incorrecg pw'         else:             return 'fail'     return render_template('login.html', form=form)  @app.route('/logout') def logout():     logout_user()     return redirect(url_for('home')) import sqlite3 flask import g  class user():      def __init__(self,name,email,password, active = true):         self.name = name         self.email = email         self.password = password         self.active = active      def is_authenticated(self):         return true         #return true if user authenticated, provided credentials      def is_active(self):     return true     #return true if user activte , authenticated  def is_annonymous(self):     return false     #return true if annon, actual user return false  def get_id(self):     c = g.db.execute('select id users username = (?)', [g.user])     id = c.fetchone()     return unicode(id)     #return unicode id user, , used load user user_loader callback  def __repr__(self):     return '<user %r>' % (self.email)  def add(self):     c = g.db.execute('insert users(username,email,password)values(?,?,?)',[self.name,self.email,self.password])     g.db.commit() 

user_loader callback function way tell flask-login on "how" user id database ? since using sqllite3, need implement user_loader function query sqllite database , fetch/return userid/username have stored. like:

@login_manager.user_loader def load_user(id):     c = g.db.execute("select username users username = (?)", [id])     userrow = c.fetchone()     userid = userrow[0] # or whatever index position     return userid 

when call login_user(user), calls load_user function figure out user id.

this how process flow works:

1. you verify user has entered correct username , password checking against database.

2. if username/password matches, need retrieve user "object" user id. user object userobj = user(userid,email..etc.). instantiate it.

3. login user calling login_user(userobj).

4. redirect wherever, flash etc.