Web Development With Python and Flask

8/10/2019 Web Development With Python and Flask

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Web Development with Python

with flask, tornado and nginx

Table of contents

This book is for

Table of contents

PREFACE

Chapter 1 - Preparation

Chapter 2 - Getting your hands dirty ith !"ello #orld$%

Chapter & - 'etting up your de(elop)ent en(iron)ent

Chapter * - +aking the app look good,

Chapter - .atabases - )ade si)ple

#hat e/ll build ne0t

Chapter - +aking the app tick,

Chapter 3 - For)s

Chapter 4 - 5ser login - ith )anage)ent

Chapter 6 - An Ad)in Panel to sa(e us allChapter 17 - Prepare for the production en(iron)ent

Features

Chapter 11 - Going online

Chapter 1 - A list of addons that )ight interest you

Flask-8abel - translate your ebsite easy

Flask-Cache - Adds cache support to your Flask application,

Flask-9ogin - Flask-9ogin pro(ides user session )anage)ent for Flask, :t

handles the co))on tasks of logging in; logging out; and re)e)bering your

users< sessions o(er e0tended periods of ti)e,

Flask-+ongoAlche)y - Add Flask support for +ongo.8 using +ongoAlche)y

Flask-=Auth - guess hat it does >

Flask-=pen:.

Flask-Testing - The Flask-Testing e0tension pro(ides unit testing utilities for

Flask,

Flask-5ploads - Flask-5ploads allos your application to fle0ibly and efficiently

handle file uploading and ser(ing the uploaded files,


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This book is dedicated to Violeta

This book is for

8eginners or ad(anced in python and total beginners in eb progra))ing ith python,

?ou should ha(e a basic python knoledge,

@uick test

1, ?ou kno ho to con(ert a string to a nu)ber and (ice-(ersa

2, Can you rite a si)ple for loop in python

&, Can you create a si)ple class


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:f the anser to all abo(e is !?E'% then go ahead, :f you don/t kno; then you really

should start ith so)e basic python, There are lots of nice and free resources on net,

:t helps if you kno a little ht)l too; like !#hat does Bh1 do % for e0a)ple,

Disclaimer:

This book is ritten by an amateur; and it/s goal is to pro(ide you Dust ith a

starting point into Python - Flask eb progra))ing and gi(ing you my own versionon

ho to do things,

An amateurFrench amateurlo(er of; fro) =ld French and ulti)ately fro) 9atin

a)atore) no), a)ator; lo(er> is generally considered a person attached to a particular

pursuit; study; or science in a non-professional or unpaid )anner, A)ateurs often ha(e

little or no for)al training in their pursuits; and )any are autodidacts self-taught>,

ikipedia>

Alternati(es better than this book,

1, The flask docu)entation itself is pretty good

2, httpe0ploreflask,co)

&, Flask #eb .e(elop)ent .e(eloping #eb Applications ith Python by +iguel

Grinberg

*, +iguel Grindberg/s blog - free

, :nstant Flask #eb .e(elop)ent by Ron .uPlain, There are e(en youtube )o(ies on flask,

: re)ind you thatYou can do things differently and more optimized!"ere : rite )y

on idea on ho things should be, :f you/re good in front-end :/) sure you ould find

better alternati(es, :f you/re good in eb-security :/) sure you/ll find better alternati(es

for e0a)ple,
http://exploreflask.com/http://exploreflask.com/


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PREFACE

Flask is )ini)al and si)ple, ?ou don/t get =R+/s; Ad)in Panels and other stuff that

.Dango has out of the bo0, ?ou can install a (ery cool ad)in panel ith Dust 1 line of

code !pip install flask-ad)in% and integrate it ith &-* lines in your app,

:t is easy to learn; poerful and co)bined ith Tornado it produces aeso)eperfor)ance e(en on a s)all HP' of 1GhI,

rite in http,google,co)trends!Flask Python%
http://www.google.com/trends/http://www.google.com/trends/http://www.google.com/trends/


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#hat you see is the trending of Flask Progra))ing, Pretty cool isn/t it

Quick preview on what well build in thisbook

A si)ple user-tracking database )anage)ent syste) ith pagination; ad)in panel;

login; security,

As e0tra e/ll discuss in the last chapter; best practices for production en(iron)ent and

opti)iIing it for a high traffic app,


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Chapter 1 - Preparation

?ou can skip this chapter if you already ha(e a linu0 en(iron)ent set up and you don/t

hat to setup a ne one,

Suggestion:

For J per )onth; : strongly suggest that you get a HP' at digitalocean,co), :n fact : ill

gi(e you a gift of J17 if you sign up no using this link you/ll recei(e the )oney in your

account after you sign in and get a ne droplet> httpgoo,glAr9(y0this is a referal link

to )e fro) .igital=cean; this ay you can say thank you for this book and get J17>

- you get a static ip; you can add (ery easy a do)ain na)e and it/s (ery fast, Ko

August 271*> you can choose locations fro) Ke ?ork; 'an Francisco; A)sterda);

'ingapore; 9ondon,

let/s get started

1. Install Uuntu latest version

. "ogin into ssh

This book assu)es that you are fa)iliar ith ter)inal co))ands and running re)ote

co))ands ith putty, :f you need help read this article

https,digitalocean,co)co))unitytutorialsho-to-log-into-your-droplet-ith-

putty-for-indos-users

Tip if you use #indos; install Putty then install httpscode,google,co)psuperputtyand you ha(e a nice putty )anag)ent ith )ultiple indos,

Co))ands to run

df -h

ifcong a

ping c 4 google.com

L if you get unknon host L - sudo nano etcresol(,conf na)eser(er 162,14,1,1 line

don> na)eser(er 4,4,4,4

sudo apt-get update && sudo apt-get upgrade

MsshN

sudo apt-get install -y openssh-server

sudo nano /etc/ssh/sshd_cong

sudo restart ssh
http://goo.gl/ArLvyxhttps://www.digitalocean.com/community/tutorials/how-to-log-into-your-droplet-with-putty-for-windows-usershttps://www.digitalocean.com/community/tutorials/how-to-log-into-your-droplet-with-putty-for-windows-usershttps://code.google.com/p/superputty/https://code.google.com/p/superputty/http://goo.gl/ArLvyxhttps://www.digitalocean.com/community/tutorials/how-to-log-into-your-droplet-with-putty-for-windows-usershttps://www.digitalocean.com/community/tutorials/how-to-log-into-your-droplet-with-putty-for-windows-usershttps://code.google.com/p/superputty/


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sudo apt-get install -y htop zip rar unrar

sudo apt-get install -y mysql-client mysql-server

sudo apt-get install -y nginx

Meb)inNsudo nano /etc/apt/sources.list

- de! http"//do#nload.#e!min.com/do#nload/repository sarge contri!

#get -q http"//###.#e!min.com/$cameron-%ey.asc-- ' sudo apt-%ey add -

sudo apt-get update

sudo apt-get install #e!min

MfailtobanNsudo apt-get install -y fail(!an

sudo nano /etc/fail(!an/$ail.conf

check that you ha(e this configuration

MsshN

enabled O true

port O ssh

filter O sshd

logpath O (arlogauth,log

)a0retry O &

sudo /etc/init.d/fail(!an restart

sudo fail(!an-client status

sudo apt-get install -y !uild-essential python python-dev python-pip python-

mysqld! li!mysqlclient-dev supervisor li!memcached-dev memcached

python-memcache

pip install )as% )as%-login )as%-mail sqlalchemy )as%-sqlalchemy )as%-#tf

)as%-migrate tornado )as%-cache simpleencode

pip install pdfminer )as%-admin )as%-security
http://download.webmin.com/download/repositoryhttp://www.webmin.com/jcameron-key.aschttp://download.webmin.com/download/repositoryhttp://www.webmin.com/jcameron-key.asc


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#gin$ pronounced engine-0> is an open source re(erse pro0y ser(er for "TTP;

"TTP'; '+TP; P=P&; and :+AP protocols; as ell as a load balancer; "TTP cache;

and a eb ser(er origin ser(er>, The ngin0 proDect started ith a strong focus on high

concurrency; high perfor)ance and lo )e)ory usage,

%emin is a eb-based syste) configuration tool for 5ni0-like syste)s; although recent

(ersions can also be installed and run on #indos, #ith it; it is possible to configure

operating syste) internals; such as users; disk uotas; ser(ices or configuration files; asell as )odify and control open source apps; such as the Apache "TTP 'er(er; P"P or

+y'@9,


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&ailan is softare to protect co)puter ser(ers fro) single-source brute-force attacks,

Fail2ban is an intrusion pre(ention fra)eork ritten in the Python progra))ing

language, :t is able to run on P=':Q syste)s that ha(e an interface to a packet-control

syste) or fireall installed locally for e0a)ple; iptables or TCP #rapper>,

pip is a package )anage)ent syste) used to install and )anage softare packages

ritten in Python,

'ornadois a scalable; non-blockingeb ser(er and eb application fra)eork ritten

in Python,

Tornado is noted for its high perfor)ance, :t tries to sol(e the C17k proble) affecting

other ser(ers, The folloing table shos a bench)ark test of Tornado against other

Python-based ser(ers

'er(er 'etup Reuests per second

Tornado ngin0;four frontends 421&
http://en.wikipedia.org/wiki/Asynchronous_IOhttp://en.wikipedia.org/wiki/Asynchronous_IOhttp://en.wikipedia.org/wiki/Nginxhttp://en.wikipedia.org/wiki/Nginxhttp://en.wikipedia.org/wiki/Asynchronous_IOhttp://en.wikipedia.org/wiki/Nginx


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Tornado =ne single-threaded frontend &&&

.Dango Apache)odsgi 222&

eb,py Apache)odsgi 27

CherryPy 'tandalone 34

Chapter 2 - Gettin !our hands dirt! with "#ello $orld%&

()* 'I( *& '+, D-Y: the fastest ay to learn this book is to type e(erything )anually

fro) it, Copy-paste is not producti(e for learning progra))ing unless you understand

177S the code, :f you )ake a typo; then the si)ple action of debugging it ill gi(e you a

reard in learning,

:f you already ha(e a ebser(er and you skipped the first Chapter; run and install the

folloing

sudo apt-get install -y !uild-essential python python-dev python-pip python-mysqld!li!mysqlclient-dev supervisor li!memcached-dev memcached python-memcache

pip install )as% )as%-login )as%-mail sqlalchemy )as%-sqlalchemy )as%-#tf )as%-

migrate tornado )as%-cache simpleencode

pip install pdfminer )as%-admin )as%-security

#ello $orld Application

Create a ne directory under ho)e

cd /home

m%dir hello#orld

create a ne file na)ed run,py
http://en.wikipedia.org/wiki/Django_(web_framework)http://en.wikipedia.org/wiki/Mod_wsgihttp://en.wikipedia.org/wiki/Mod_wsgihttp://en.wikipedia.org/wiki/CherryPyhttp://en.wikipedia.org/wiki/Django_(web_framework)http://en.wikipedia.org/wiki/Mod_wsgihttp://en.wikipedia.org/wiki/CherryPy


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nano run.py

run.py

from )as% import *las%app + *las%,__name__

app.route,/

def hello_#orld,"

return 0ello 1orld2

if __name__ ++ __main__"

app.run,

save it /')"0 then 2Y3 ,nter

now type:

python run.py

'hen from your rowser open

http:44your5server5ip:67774

:f you forgot your ser(er ip; rite

wget 89*8 http:44ipecho.net4plain echo

=r if you use digitalocean you can see it after you login on your account after your HP'

na)e,

?ou should see a hite page ith a 2+ello %orld!3, That/s all,

After you are done ad)iring your first flask application; hit CTR9C,

()* 'I( *& '+, D-Y: you can rite on top of run,py U$usrbinpython then ch)od 0run,py so you can Dust type ,run,py instead of !python run,py%,

:f you get error like -bash ,run,py usrbinpythonV+ bad interpreter Ko such file or

directory

apt-get install dos2uni0 then rite !dos2uni0 run,py%, Mand configure your :.E to use 9ine

separator 5ni0 and ='Q, code style-general in :ntelliWN

:f you already kne this; and : offended you ith this ti)e asting info; : apologiIe$
http://127.0.0.1:5000/http://ipecho.net/plainhttp://127.0.0.1:5000/http://ipecho.net/plain


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Chapter ' - (ettin up !our develop)ent environ)ent

The settings are Dust )y preferences, ?ou are free to use hate(er you ant of course,

5sing nano to edit scripts is not producti(e, "ere/s a screenshot on ho : do it, ?ou are

free to choose hate(er )ethod suits you hoe(er,

?ou see :ntelliW 'tudio and 'uperPutty,

The te0t is so s)all because : ha(e a 2701**7 resolution best )oney spend e(er ona good )onitor>; : ha(e .E99 5231&"+ no it/s about J77>

: the)ed :ntelliW ith a dark the)e; so )y eyes don/t hurt fro) so )uch hite, ?ou

prefer another color - httpideacolorthe)es,orgho)e they ha(e uite a fe the)es,

Python https,python,orgdonload

:ntelliW 'tudiohttp,Detbrains,co)ideadonload

Putty httpthe,earth,liXsgtatha)puttylatest04putty,e0e
http://ideacolorthemes.org/home/https://www.python.org/downloadhttp://www.jetbrains.com/idea/download/http://www.jetbrains.com/idea/download/http://the.earth.li/~sgtatham/putty/latest/x86/putty.exehttp://ideacolorthemes.org/home/https://www.python.org/downloadhttp://www.jetbrains.com/idea/download/http://the.earth.li/~sgtatham/putty/latest/x86/putty.exe


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'uperPutyhttpscode,google,co)psuperputty

'tart :ntelliW; configure hate(er it asks you; choose !Ke ProDect% - Python - don/t

check .Dango; Google App Engine etc> Dust click ne0t, ne0t, Python interpreter, Ka)e

your proDect,

S;ip this step if you plan to use your own computer for development.


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Ko let/s test if e(erything is going ok,

)emove the +ello%orld directory. You are not a eginner anymore :A

9et/s no structure the app a little,Create a ne directory na)ed flasktutorial,

m%dir )as%_tutorial

cd )as%_tutorial

m%dir app

m%dir app/static

m%dir app/templates

:n the )ain directory !flasktutorial% create a file na)ed run,py

:nside app create a55init55.pyand views.py

"ere/s the standard folder structure of a Flask App,

'o e(erything should look like this

)as%_tutorial/

app/

__init__.py

static/

templates/

vie#s.py

run.py

The app folder is containing the bread and butter, 'tatic folder is for css; Ds; Dpg etc, files,

The init,py is here e ill create our app obDect, The run,py is here the ser(er

ill be,


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Edit app455init55.py

from )as% import *las%

3 ene the 1567 application o!$ect

app + *las%,__name__

from app import vie#s

"ere e Dust create the app obDect and i)port the (ies in it, :n (ies e keep all thelogic on ho the app responds to url reuests,

Edit app4run.py

import tornado

from tornado import autoreload

from tornado.#sgi import 15678ontainer

from tornado.httpserver import 099:5erver

from tornado.ioloop import 7;oop

from tornado.log import ena!le_pretty_logging

from app import app

ena!le_pretty_logging,

http_server + 099:5erver,15678ontainer,app

http_server.listen,

ioloop + tornado.ioloop.7;oop,.instance,

autoreload.start,ioloop

ioloop.start,

This is a default configuration on 1 core for the tornado ser(er, #e/ll start like this

because you/ll Dust rite it once and you/ll use it until the end of the book,


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:f you ant to go into details ith tornado; at the end of the book :/ll gi(e you a better

config; but for no this is )ore than enough,

Pretty logging for a nice display on the ter)inal, Kotice that e start the app on port

1BBC$

MofftopicN

If 1BBC doesn=t tell you anything then here=s the wi;ipedia intro to it.

"eetor 1BBC>; also knon as eleetor leetspea;; is an alternati(e alphabetfor the

English languagethat is used pri)arily on the :nternet, :t uses (arious co)binations of

A'C::characters to replace9atinateletters, For e0a)ple; leet spellings of the ord leet

include 1337and l33tY eleet)ay be spelled 31337or 3l33t,

The ter) leet is deri(ed fro) the ord elite, The leet alphabet is a specialiIed for) of

sy)bolicriting, 9eet )ay also be considered a substitution cipher;although )any

dialectsor linguistic (arietiese0ist in different online co))unities, The ter) leetis also

used as an adDecti(eto describe for)idable proess or acco)plish)ent; especially in

the fields of online ga)ingand in its original usage Z co)puter hacking,

MofftopicN

Edit app4views.py

from app import app

app.route,/

app.route,/index

def index,"
http://en.wikipedia.org/wiki/Alphabethttp://en.wikipedia.org/wiki/English_languagehttp://en.wikipedia.org/wiki/Internethttp://en.wikipedia.org/wiki/ASCIIhttp://en.wikipedia.org/wiki/Latin_alphabethttp://en.wikipedia.org/wiki/Latin_alphabethttp://en.wikipedia.org/wiki/Elitehttp://en.wikipedia.org/wiki/Symbolhttp://en.wikipedia.org/wiki/Substitution_cipherhttp://en.wikipedia.org/wiki/Substitution_cipherhttp://en.wikipedia.org/wiki/Dialectshttp://en.wikipedia.org/wiki/Dialectshttp://en.wikipedia.org/wiki/Variety_(linguistics)http://en.wikipedia.org/wiki/Adjectivehttp://en.wikipedia.org/wiki/Adjectivehttp://en.wikipedia.org/wiki/Online_gamehttp://en.wikipedia.org/wiki/Hacker_(hobbyist)http://en.wikipedia.org/wiki/Alphabethttp://en.wikipedia.org/wiki/English_languagehttp://en.wikipedia.org/wiki/Internethttp://en.wikipedia.org/wiki/ASCIIhttp://en.wikipedia.org/wiki/Latin_alphabethttp://en.wikipedia.org/wiki/Elitehttp://en.wikipedia.org/wiki/Symbolhttp://en.wikipedia.org/wiki/Substitution_cipherhttp://en.wikipedia.org/wiki/Dialectshttp://en.wikipedia.org/wiki/Variety_(linguistics)http://en.wikipedia.org/wiki/Adjectivehttp://en.wikipedia.org/wiki/Online_gamehttp://en.wikipedia.org/wiki/Hacker_(hobbyist)


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return ?0ello@ 1orld(2?

"ere e )ap the and the inde0 to our !inde0>% function; that Dust returns a si)ple te0t,

Ko go in the )ain folder and run !python run.py

% then ith our broser test the app at

httpyourser(erip1&&3

you should see a !"ello; #orld2$% on it,

Chapter * - +akin the app look ood,

Titter


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Alin% href+?//netdna.!ootstrapcdn.com/!ootstrap/

DD !ootstrap_version GG/css/!ootstrap.min.css? rel+?stylesheet? /

Alin% href+?//netdna.!ootstrapcdn.com/!oots#atch/

DD !oots#atch_version GG/DD !oots#atch_theme GG/!ootstrap.min.css?rel+?stylesheet?

Alin% href+?/static/css/main.css? rel+?stylesheet? /

Alin% rel+?shortcut icon? href+?/static/img/favicon.ico? /

DE !loc% style_!loc% EGD3 page-specic 855 3GDE end!loc% EG

Ascript src+?//cdn$s.cloud)are.com/a$ax/li!s/modernizr/

DD modernizer_version GG/modernizr.min.$s?A/scriptD3 Lodernizr must !e

here@ a!ove !ody tag. 3G

DE !loc% head_script EGD3 defer-incapa!le M5 !loc% 3GDE end!loc% EG

A/head

A!ody

{% include 'includesna!"html' %}D3 pull in nav!ar 3G

Adiv class+?container? id+?maincontent?

{% include 'includesfash#message"html' %}D3 page-level

feed!ac% notices 3G

Adiv id+?!ody_content?

{% block content %}{$ main content area $}{% endblock %}

A/div A/divA2-- /container --

Afooter

Adiv id+?footer? class+?container?

{% block ooter %}{% endblock %}

A/divA2-- /footer --

A/footer

Ascript src+?https"//a$ax.googleapis.com/a$ax/li!s/$query/DD $query_version

GG/$query.min.$s?A/script

Ascript src+?//netdna.!ootstrapcdn.com/!ootstrap/

DD !ootstrap_version GG/$s/!ootstrap.min.$s?A/script Ascript src+?/static/$s/main.$s?A/script

A/!ody

A/html


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(ro tip of the day:instead of the !oots#atch - NslateO theme@ replace it #ith the

one of your li%ing.

?ou notice so)e tags like

{% include 'includesna!"html' %}

As you probably suspect in the te)plates folder create another folder na)ed includes,

#e ill use it to structure our code in a nice ay; adding na(igation to our site )uch

)ore easy,

The variale EE)eans dyna)ic content, 'o)ething like9otal users" &php

total#users( &)in php

4app4templates4includes4nav.html

Anav class+?nav!ar nav!ar-default? role+?navigation?

Adiv class+?nav!ar-header?

A!utton type+?!utton? class+?nav!ar-toggle? data-toggle+?collapse?

data-target+?3!s-example-nav!ar-collapse-


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DE set icon + icon-info-sign EG

DE endif EG

DE for category@ message in messages EG

Adiv class+?alert alert-DD category GG?

Ai class+?DD icon GG?A/i&n!spQ

Aa class+?close? data-dismiss+?alert?RA/a DD message GG

A/div

DE endfor EG

DE endif EG

DE end#ith EG

:n the static folder create = folders" css* img* +s" 7n the folder css create a le

named main"cssand in the $s one main"+s"Bou can use the to add custom

things to your template.

After all this preparation; let/s finally create ourinde$.html

4app4templates4inde$.html

DE extends ?!ase.html? EG

DE !loc% content EG

Adiv style+?font-size"


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from )as% import render_template

import logging

app.route,/

app.route,/indexdef index,"

return render_template,?index.html?

Ko go in the )ain folder and run !python run.py%

8ecause learning so)ething should be fun; let/s uickly test our !ebser(er% to see ho

it perfor)s, :deally you should use another ser(er or )achine for this,

Copy paste so)e rando) loren ipsu) in the inde0,ht)l so you load the page so)e

)ore, [eep in )ind that this is a si)ple static page; no database ueries; no other funny

stuff is inside,

sudo apt-get install apache,-utilsno for the bench)ark rite

a 8n 1777 8c 177 http:44server5ip:1BBC4

9ook at 'ime per re9uest(alue, : get 12,* M)sN )ean> on an i& laptop ith *G8

ra), Try playing ith increasing the -c to 27 for e0a)ple,

(ro tip of the day: This testing is a little useless if you are running the test fro)

localhost and you are not interacting ith any database, ?ou should run it fro) a

different )achine to get )ore accurate results, Also the tornado is set up to use Dust 1

core of your )achine, 8ut this is for the last chapter,

9ater on; e/ll use ngin0 to )ake it e(en faster,
http://server_ip:1337/http://server_ip:1337/


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Chapter - .atabases - )ade si)ple

What well build next:

'@9Alche)y is the Python '@9 toolkit and =bDect Relational +apper that gi(es

application de(elopers the full poer and fle0ibility of '@9,

An =R+ is good for abstracting the datastore slite; )ysl; oracle; etc etc> in order to

pro(ide an interface that can be used in your code,

:f you didn/t installed it fro) the first chapter go ahead and rite

pip install flask-sqlalchemy

8ecause e/ll use lots of configuration constants in our app, 9et/s organiIe the) in a

config file,


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:n the )ain folder flas;5tutorial here the run.pyis> create a ne file called

config.py

4config.py

import os

!asedir + os.path.a!spath,os.path.dirname,__le__

class 8ong,o!$ect"

CTJ6 + *alse

9C597P6 + *alse

5U;K;80CLB_K9KTK5C_JV7 +

K::_PKLC + *las% 9est

5C8VC9_WCB + thisisaveryhardsecret2


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class 9esting8ong,8ong"

5U;K;80CLB_K9KTK5C_JV7 + sqlite"/// X os.path.$oin,!asedir@

d!.sqlite

5U;K;80CLB_L76VK9C_VC: + os.path.$oin,!asedir@ d!_repository 9C597P6 + 9rue

Ko e should let kno that the app ill use this configuration

4app455init55.py

from )as% import *las%

from )as%.ext.sqlalchemy import 5U;Klchemy

import logging

app + *las%,__name__

app.cong.from_o!$ect,cong".e!elopment/ong

d! + 5U;Klchemy,app

logger + logging.get;ogger,__name__

logger.set;evel,logging.7P*

fro) app i)port (ies; )odels

Ko a )odel for the database is reuired; hich are a collection of classes that e/ll use

to interact ith the db,

A dataase modelis a type of data )odel that deter)ines the logical structure of a

database and funda)entally deter)ines in hich )anner data can be stored; organiIed;


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and )anipulated, The )ost popular e0a)ple of a database )odel is the relational

)odel; hich uses a table-based for)at, MikipediaN

create a model.pyin app

4app4model.py

import datetime

from app import d!

class 9rac%ing,d!.Lodel"

__ta!lename__ + ?trac%ing?

id + d!.8olumn,d!.7nteger@ primary_%ey+9rue

user_ip + d!.8olumn,d!.5tring,4Y

user_agent + d!.8olumn,d!.5tring,


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from )as%.ext.admin.contri!.sqla import Lodel[ie#

from app import Z

import logging

F ,$ecutes efore the first re9uest is processed.

Gapp.efore5first5re9uestdef efore5first5re9uest@A:

logging.info@H88888888888888888888 initializing everything 888888888888888888888HA

d.create5all@A

app.route,/

app.route,/index

def index,"

new#tracking 0 Tracking12

new#tracking"add#data1request"remote#addr*request"headers"g

et1'3ser-4gent'22

list#records 0 new#tracking"list#all#users12

or record in list#records5

logging"ino1record"user#ip 6 7 7 6 record"user#agent2

return render_template,?index.html?

/he Gapp.efore5first5re9uest'his creates the dataase when you first access your wesite.

?ou can test the database ith a uick (ie nano db,slite \,you should see your table

there,

5sing re9uest e get the (isitor ip and the user-agent and e store it each ti)e e

refresh the page,

=pen your broserhttpser(erip1&&3

And !python run,py%

?ou should see in the ter)inal so)ething like this

M: 1*7423 112226 (ies14N 162,14,7,12& +oIilla,7 #indos KT ,&Y #=#*>

Apple#eb[it&3,& ["T+9; like Gecko> Chro)e&,7,164,1*& 'afari&3,&
http://server_ip:1337/http://server_ip:1337/http://server_ip:1337/


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and each ti)e you refresh it; )ore records are added,

Chapter 0 - +akin the app tick,

Ko need to rite no; Dust read,

'o the url routing is done like this

app.route,/#elcome

def #elcome,"

return render_template,#elcome.html 3 render a template

This )eans that if you rite you5wesite.com4welcome you ill get the

2welcome.html3fro) the te)plates directory,

?ou can also use the routing to display static content like this

app.route,?/favicon.ico?

def favicon,"

return app.send_static_le,?img/favicon.ico?

or other static contentsee httpstacko(erflo,co)a1*7*7&617&1263

from )as% import *las%@ request@ send_from_directory

app.route,/ro!ots.txt

app.route,/sitemap.xml

def static_from_root,"

return send_from_directory,app.static_folder@ request.path\


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app.route,/post/int5post#id)

def sho#_post,post#id"

3 sho# the post #ith the given id@ the id is an integer

return :ost Ed E post#id

?ou can co)bine the)

8app"route1'hello'2

8app"route1'helloname)'2

def hello,name+Pone"

return render_template,hello.html@ passed#name0name

Kotice the (ariable na)e ith the default Kone, ?ou can use it in your te)plates using ]]

\ ^^

like BpGreeting passed#name EE$Bp

and you can specify http )ethods

_app,route

if re9uest.method K(*S'K:

do5the5login@A

else:

show5the5login5form@A

Ko let/s )odify the inde0,ht)l te)plate to sho nicely the records in our database and

add a ne url to display a record by id,

4app4views.py

from )as% import render_template@ request

from app import Z

from models import Z

app.route,/

app.route,/index

def index,"

ne#_trac%ing + 9rac%ing,

ne#_trac%ing.add_data,request.remote_addr@ request.headers.get,Jser-


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Kgent

list#records 0 new#tracking"list#all#users12

return render_template,?index.html?@ list#records0list#records

()* 'I( *& '+, D-Y:?ou can use /')"0-"'0"to re-for)at your code in :ntelliW, Try

it,

The return Tracking,uery,all> returns a list ith all records, #e passed the list of all

records to our inde0 te)plate,

Quick intro into ina2 3the te)plates that4lask is usin5

read more herehttp:44NinNa.pocoo.org4docs4dev4templates4

for the if we have:

]S if True S^

it/s true

]S endif S^

a for statement is done li;e this

]S for ite) in listofite)s S^

do so)ething ith ]] ite) ^^]S endfor S^

and for if4else:

]S if kenny,sick S^

[enny is sick,

]S elif kenny,dead S^

?ou killed [enny$ ?ou bastard$$$

]S else S^

[enny looks okay --- so far]S endif S^

you can also use else with for li;e this:

Bul

]S for user in users S^

Bli]] user,userna)e ^^Bli
http://jinja.pocoo.org/docs/dev/templates/http://jinja.pocoo.org/docs/dev/templates/http://jinja.pocoo.org/docs/dev/templates/


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]S else S^

BliBe)no users foundBe)Bli

]S endfor S^

Bul

Mgreat e0a)ples taken fro) DinDa2 docu)entationN

so e )odify our inde0,ht)l

4app4templates4inde$.html

]S e0tends base,ht)l S^

]S block content S^

Bdi( styleOfont-siIe 1,e)Yte0t-align center

Bh&Test FlaskBh&

Bhr

O for record in list5records OE

record.user5ip EE

Pr 4Q

record.user5agent EE

O endfor OE

Bdi(

]S endblock content S^

Test it in your broser, #orks$ but ait; it looks ugly, 9et/s rap it up in a bootstrap nice

table,

DE extends ?!ase.html? EG

DE !loc% content EG

Adiv style+?font-size"


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tr)

td) {{ record"user#ip }}td)

td){{ record"user#agent }}td)

tr)

{% endor %}

table) A/div

DE end!loc% content EG

and edit the

4app4static4css4main.css

td D

font-size" F.HemQ

text-align" leftQ

G

Test it, 9ooks )uch better no isn/t it

Goin even 4urther

(rolem if you refresh the page couple of ti)es you get bigger and bigger listing, 9et/s

add pagination to it, #ith '@9Alche)y pagination is piece of cake, "ere/s the recipesince :/) supposing you don/t ha(e ti)e to read the official docu)entation,

:n config,py in the )ain ConfigobDect> add "IS'I#LS5(,)5(-L, 6

class ConfigobDect>

.E85G O False

TE'T:KG O False

'@9A9C"E+?.ATA8A'E5R: O


32/62

4app4views.py

fro) flask i)port renderte)plate; reuest

fro) app i)port L

fro) )odels i)port L

_app,route


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Btable

Pul classHpaginationHQ

O8 for page in list5records.iter5pages@A OE

O if page OE

O if page ! list5records.page OE PliQ Pa hrefH url5for@Kinde$K page pageA EEHQ page EEP4aQ P4liQ

O else OE

Pli classHactiveHQ Pa hrefHFHQPstrongQ page EEP4strongQP4aQ

P4liQ

O endif OE

O else OE

PliQ Pspan classellipsisQRP4spanQ P4liQ

O endif OE

O8 endfor OE

P4ulQ

Bdi(

]S endblock content S^

Test it; and see the greatness of your ork$

M:f so)ething is rong; copy-paste the file fro) the githubN

*ptional Improvements:

add a time formatting:

Btd ]] record,atti)e.strftime@KOY8Om8Od O+:O>:OSKA ^^Btd

order the records y created time:

4app4models.py

\...]

rom sqlalchemy import asc* desc

\...]

def list_all_users,self@page@ ;7597P65_:CV_:K6C"

return

9rac%ing.query"order#by1desc1Tracking"at#time22"paginate,page@

;7597P65_:CV_:K6C@ *alse


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-dd some test data

'ince you/(e been connecting Dust fro) your co)puter; add a ne different record to the

database by accessing it fro) a eb pro0y,

httpssi)ple-pro0y,co)Mnote if you de(elop fro) a local netork you can open the port fro) your routerN

Mnote2 if you don/t like this Dust add so)e du))y test dataN

du))y test dataY

so)ehere in inde0

ne#_user + 9rac%ing,user_ip+O


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and duplicate theinde$.html to trac;5ip.html

Moptional you can )odify it/s title fro) Test Flask to Track :P or so)ethingN

')all instant ho)eork, :f you add )ore test data; you see that the pagination doesn/t

ork, Fi0 it,

M------------ spoiler alert ------------N

M------------ spoiler alert ------------N

M------------ spoiler alert ------------N

M------------ spoiler alert ------------N

M------------ spoiler alert ------------N

M------------ spoiler alert ------------N

M------------ spoiler alert ------------N

M------------ spoiler alert ------------N

M------------ spoiler alert ------------N

M------------ spoiler alert ------------N

M------------ spoiler alert ------------N

M------------ spoiler alert ------------N

M------------ spoiler alert ------------N

M------------ spoiler alert ------------N

M------------ spoiler alert ------------N

M------------ spoiler alert ------------N

M------------ spoiler alert ------------N

change the ]]urlfor`inde0/>^^ in the pagination at the botto) to urlfor!trackuserip%>N

Test it http:44server5ip:1BBC4trac;41.11.1.6T

-lternative ith Flask-Restless create an AP: for addingdeletingupdating a record,

Flask-Restless pro(ides si)ple generation of Re'Tful AP:s for database )odels definedusing '@9Alche)y or Flask-'@9Alche)y>, The generated AP:s send and recei(e

)essages in W'=K for)at,
http://server_ip:1337/track/91.121.21.58http://server_ip:1337/track/91.121.21.58


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Chapter 6 - For)s

9et/s create so)e for)s to add ne records to our database,

create a ne file4app4forms.py

4app4forms.py

from app import Z

from #tforms.validators import Vequired@ ;ength

from #tforms import *orm@ 9ext*ield

class 9rac%ing7nfo*orm,*orm"

user_ip + 9ext*ield,user_ip@ validators+\Vequired,@ ;ength,max+4Y@

message+max 4Y characters]

user_agent + 9ext*ield,user_agent@ validators+\;ength,max+4Y@ message+max

4Y characters]

#e are using #TF For)s, ?ou can play ith the) like adding different fields; (alidators, 8ut/s

let/s keep it basic for no,

change the i)ports of app(ies,py to

4app4views.py

i)port logging

fro) flask i)port renderte)plate; reuest; flash

fro) )odels i)port L

from forms import

#e/re i)porting logging to do so)e debuging in the app; the for)s and !flash% to display so)e

feedback to the user,


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and add this to (ies,py

4app4views.py

\...]

app.route,/add_record@ methods+\6C9@ :59]

def add_record,"

form + 9rac%ing7nfo*orm,request.form

if request.method ++ :59"

if form.validate,"

ne#_trac%ing + 9rac%ing,

user_ip + form.user_ip.data

user_agent + form.user_agent.data logging.info,?adding ? X user_ip X ? ? X user_agent

ne#_trac%ing.add_data,user_ip@ user_agent

)ash,?added successfully?@ category+?success?

return render_template,?add_record.html?@ form+form

5pdate the na(igation bar


Bna( classOna(bar na(bar-default roleOna(igation

Bdi( classOna(bar-header

Bbutton typeObutton classOna(bar-toggle data-toggleOcollapse data-targetOUbs-

e0a)ple-na(bar-collapse-1

Bspan classOsr-onlyToggle na(igationBspan

Bspan classOicon-barBspan


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Bbutton

Ba classOna(bar-brand hrefOTest FlaskBa

Bul classOna( na(bar-na( na(bar-right

PliQPa hrefH4add5recordHQ-dd recordP4aQP4liQ

Bul

Bdi(

Bna(

Test it by adding fe records to the db,You should also see in the terminal the deug

message.

The )ost i)portant part of this chapter are 2 ho)eorks that you really should do, They are

si)ple and should take 2-& )inutes for the first one and about 17 )inutes for the second,

#o)ework 1,

-dd a validator for ip address in the form.

+I#': You should search the documentation of %'&&orms

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N


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M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

fro) tfor)s,(alidators i)port Reuired; 9ength;I(-ddress

userip O Te0tField

#o)ework 2,

Re)e)ber the trac;5user5ip to display a record filtered by ip Add to the trac;5ip.html page a

for) ith one input te0t here you can enter the :P and a button sub)it, .isplay the filtered ip


40/62

page after,

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

M spoiler alert N

add

4app4forms.py

class Uueryne*orm,*orm"

user_ip + 9ext*ield,user_ip@ validators+\Vequired,@ 7:Kddress,message+?7nvalid

7: Kddress?]


BliBa hrefOtrack@uery recordBaBli


41/62

4app4views.py

modify trac;5user5ip function to:

app.route,/trac%@ methods+\6C9@ :59]

app.route,/trac%/Auser_ip@ methods+\6C9@ :59]

app.route,/trac%/Auser_ip/Aint"page@ methods+\6C9@ :59]

def trac%_user_ip,user_ip+??@ page+


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di! class07row7)

di! class07well bs-component7)

orm class07orm-hori=ontal7 method07post7 action077)

eldset)

legend)>earch by 9:legend)

di! class07orm-group7)

label or07user#ip7 class07col-lg-? control-label7)3ser

9:label)

di! class07col-lg-@7)

{{orm"user#ip 1class07orm-control72}}

{% or error in orm"errors"user#ip %} br)

di! class07alert alert-danger7 style07display5

inline-block7)

{{error}}

di!)

{% endor %}

di!)

di!)

di! class07orm-group7)

di! class07col-lg-? col-lg-oAset-?7)


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button type07submit7 class07btn btn-

primary7)>earchbutton)

di!)

di!)

eldset)

orm)

di!)

Ata!le class+?ta!le ta!le-striped ta!le-!ordered ta!le-hover?

Athead

Atr

AthKt 9imeA/th

Ath7:A/th

AthJser KgentA/th

A/tr

A/thead

DE for record in list_records.items EG

Atr

Atd DD record.at_time.strftime,EB-Em-Ed E0"EL"E5 GGA/td

Atd DD record.user_ip GGA/td


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AtdDD record.user_agent GGA/td

A/tr

DE endfor EG

A/ta!le

Aul class+?pagination?

DE- for page in list_records.iter_pages, EG

DE if page EG

DE if page 2+ list_records.page EG

Ali Aa href+?DD url_for,'track#user#ip'@ user#ip 0 user#ip@ page +

page GG?DD page GGA/a A/li

DE else EG

Ali class+?active? Aa

href+?3?AstrongDD page GGA/strongA/a A/li

DE endif EG

DE else EG

Ali Aspan class+ellipsis^A/span A/li

DE endif EG

DE- endfor EG

A/ul

A/div

DE end!loc% content EG


45/62

Chapter 7 - 8ser loin - with )anae)ent

To rite yourself the user registration; e)ail confir)ation; forgot passord etc, ould

take so)e ti)e and you/d ha(e to be (ery good to rite it ithout bugs and opti)iIed,

#e are grateful for ha(ing &las;8Securityto sa(e our souls,

httpspythonhosted,orgFlask-'ecurityinde0,ht)l

9et/s get our hands dirty, #e ant a user register; confir)ation by e)ail; forgot

passord and a secretpage ith a ultra-secret infor)ation inside,

#e/ll use yahoo; that has a li)it of 177 e)ails per day, For our testing purposes it ill be

ok,

:f you ha(e another )ail ser(er; Dust change the config,

For large (olu)es you can check httpsendgrid,co)

9et/s clear our pre(ious database first,

rm 8rf d.s9lite

To use &las;8Security; first let/s configure it

add this (alues in the )ain Config

4config.py

5C8JV79B_VC6759CVKT;C + 9rue

5C8JV79B_VC8[CVKT;C + 9rue 5C8JV79B_9VK8WKT;C + 9rue

5C8JV79B_:K551V_0K50 + shaS


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LK7;_J5C_9;5 + *alse

LK7;_J5CVPKLC + emailyahoo.com

LK7;_:K551V + pass#ord

C*KJ;9_LK7;_5CPCV + emailyahoo.com

5C8JV79B_CLK7;_5CPCV + emailyahoo.com

e need to add the flask-)ail obDect

4app455init55.py

M,,,N

fro) flask)ail i)port +ail

M,,,N

)ail O +ailapp>

#e need to update our )odels,py too

4models.py

from )as%.ext.security import JserLixin@ VoleLixin@

5U;KlchemyJseratastore

roles_users + d!.9a!le,roles_users@

d!.8olumn,user_id@ d!.7nteger,@ d!.*oreignWey,user.id@

d!.8olumn,role_id@ d!.7nteger,@ d!.*oreignWey,role.id

class Jser,d!.Lodel@ JserLixin"

id + d!.8olumn,d!.7nteger@ primary_%ey+9rue

email + d!.8olumn,d!.5tring,(SS@ unique+9rue

pass#ord + d!.8olumn,d!.5tring,(SS

active + d!.8olumn,d!.Toolean,

conrmed_at + d!.8olumn,d!.ate9ime,

roles + d!.relationship,Vole@ secondary+roles_users@

!ac%ref+d!.!ac%ref,users@ lazy+dynamic

last_login_at + d!.8olumn,d!.ate9ime,

current_login_at + d!.8olumn,d!.ate9ime,

last_login_ip + d!.8olumn,d!.5tring,(SS

current_login_ip + d!.8olumn,d!.5tring,(SS

login_count + d!.8olumn,d!.7nteger

def __repr__,self"

return Amodels.Jser\email+Es] E self.email


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class Vole,d!.Lodel@ VoleLixin"

id + d!.8olumn,d!.7nteger,@ primary_%ey+9rue

name + d!.8olumn,d!.5tring,HF@ unique+9rue

description + d!.8olumn,d!.5tring,(SS

user_datastore + 5U;KlchemyJseratastore,d!@ Jser@ Vole

And the (ies,py

4views.py

\...]

from )as%.ext.security import 5ecurity@ login_required@ logout_user

\...]

security + 5ecurity,app@ user_datastore

app.route,/secret

login_required

def secret,"

return render_template,secret.html

no create a si)ple secret.htmlin te)plates and rite !secret page% in the content,

&las;8securityuses so)e te)plates, 8ecause They are si)ple; and self e0planatory; :

on/t copy paste the) here,

:/(e custo)iIed )y on te)plates ith bootstrap; also you/ll find e)ail te)plates,

"ere is the all chapter ith all the code, ?ou Dust ha(e to edit the config fileith your

mail credentials,

httpsgithub,co)Andrei.Flask8ooktree)asterflaskbookchapter4

Chapter 9 - An Ad)in Panel to save us all

&las;8-dmin

pip install &las;8-dmin
https://github.com/AndreiD/FlaskBook/tree/master/flask_book/chapter_8https://github.com/AndreiD/FlaskBook/tree/master/flask_book/chapter_8


48/62

httpsgithub,co))rDoesflask-ad)in

Flask-Ad)in is a batteries-included; si)ple-to-use Flaske0tension that lets you add

ad)in interfaces to Flask applications, :t is inspired by the dDango-ad)in package; but

i)ple)ented in such a ay that the de(eloper has total control of the look; feel and

functionality of the resulting application, official description>

#orking ith flask ad)in is (ery si)ple, "ere/s the ay to do it ith '@9Alche)y,


3 *las% and *las%-5U;Klchemy initialization here

admin + Kdmin,app

admin.add_vie#,Lodel[ie#,Jser@ d!.session

And this is all$ :t creates an ad)in panel for the 5ser; ith all the goodies that co)e ith

it,

"oe(er; e ant to custo)iIe it and to protect it with flas;8security.


3 *las% and *las%-5U;Klchemy initialization here

class Ly[ie#,Lodel[ie#" 3 isa!le model creation

can_create + *alse

3 verride displayed elds

column_list + ,login@ email

def __init__,self@ session@ ZZ%#args"

3 Bou can pass name and other parameters if you #ant to

super,Ly[ie#@ self.__init__,Jser@ session@ ZZ%#args

admin + Kdmin,app

admin.add_vie#,Ly[ie#,d!.session

To the +yHie class e can add

def is_accessi!le,self"
https://github.com/mrjoes/flask-adminhttp://flask.pocoo.org/https://github.com/mrjoes/flask-adminhttp://flask.pocoo.org/


49/62

return current_user.has_role,admin

'o here/s the code for our app, There/s no need to copy it; Dust read it line by line and try

to understand it

3 -------------------------- KL7P :KV9 ------------------------------------

class Ly[ie#,Tase[ie#"

expose,/

def index,self"

return self.render,admin/index.html

class 9rac%ingKdmin[ie#,Lodel[ie#"

can_create + 9rue

de is#accessible1sel25

return current#user"has#role1'end-user'2


super,9rac%ingKdmin[ie#@ self.__init__,9rac%ing@ session@ ZZ%#args

class JserKdmin[ie#,Lodel[ie#"

column_exclude_list + ,pass#ord

de is#accessible1sel25

return current#user"has#role1'admin'2


super,JserKdmin[ie#@ self.__init__,Jser@ session@ ZZ%#args

class Vole[ie#,Lodel[ie#"

def is_accessi!le,self"

return current_user.has_role,admin


super,Vole[ie#@ self.__init__,Vole@ session@ ZZ%#args

admin + Kdmin,app@ name+?*las% 9est Kdmin?

admin.add_vie#,9rac%ingKdmin[ie#,d!.session

admin.add_vie#,JserKdmin[ie#,d!.session

admin.add_vie#,Vole[ie#,d!.session


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3 -------------------------- KL7P :KV9 CP ---------------------------------

Chapter 1: - Prepare 4or the production environ)ent

Ti)e has co)e to let the orld kno on hat e/(e been spending our resources,,,especially

ti)e,

8efore e (enture into spending JJJ into ad(ertising it > let/s )ake sure the production release is

good,

E(erything : kno; : share it ith you, :f any of you are )ore knoledgeable than )e and you

ant to share this ith the people that ill read this book; please e)ail )e your suggestions

using the httpandroidad(ance,co)contact for),

#hat e plan to do

Ti)e to lea(e slite and )o(e to )ysl,

:f by so)e )ysterious force our app breaks; e ant to restart auto)atically

9et/s ser(e the app fro) ngin0 ith a )odified tornado

;n order to tune the app 4or per4or)ance< lets 4irst )ake it do so)e hard work, Go into con4i

and )odi4! the LISTI!S"P#$"P%!# & '((

=ow 4or the testin lets use apache bench)ark, /he idea is to use it 4ro) a di44erent )achine

than the one !ou are hostin the app, ;4 !ou have 2 servers ust use another one< i4 !ou want to

have it on windows

Go to http>??www,apachehaus,co)?ci-bin?download,pl@and download -pache .V.17 $WV @you

have a $WV *S don=t you XA. Inside 4in you find a.e$e. )un it with (owerShell or cmd Nust li;e on linu$

'esting with:

.a.e$e 8n 177 8c 67http:44server5ip:1BBC4 @replace .a.e$e with a in linu$A

n an old i' laptop< *GB RA+< with a shitt! #..
http://androidadvance.com/http://www.apachehaus.com/cgi-bin/download.plxhttp://www.apachehaus.com/cgi-bin/download.plxhttp://server_ip:1337/http://server_ip:1337/http://androidadvance.com/http://www.apachehaus.com/cgi-bin/download.plxhttp://server_ip:1337/


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?run,p!

http_server + 099:5erver,15678ontainer,app

http_server.listen,

ioloop + tornado.ioloop.7;oop,.instance,

autoreload.start,ioloop

ioloop.start,

$ell call it sinle threaded< 1 core,

Testing on single core* sqlite database

Vequests per second" B"CD\3/sec] ,mean

9ime per request" H4S.4> \ms] ,mean

9ime per request"

Ti)e per reuest 3*,377 M)sN )ean; across all concurrent reuests>


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Alright; no e/re talking, #ith )ultithread and )ysl the perfor)ance skyrocketed,

Jsudo apt-get install ngin0

ngin0 * core tornado )ysl

Reuests per second 1B.V6MUsecN )ean>

Ti)e per reuest &31,4* M)sN )ean>Ti)e per reuest 3*,&&3 M)sN )ean; across all concurrent reuests>

+ow to configure ngin$ with flas;.

/lean and install ngin$ if you already played with it.

sudo apt-get purge nginx nginx-common nginx-full

then reinstall

sudo apt-get install nginx

Test if ngin0 is running, =pen the ip of your ser(er, ?ou should see a !hello orld fro)

ngin0% )essage,

Read this article https,digitalocean,co)co))unitytutorialsho-to-opti)iIe-

ngin0-configuration

MKote all config files are in httpsgithub,co)Andrei.Flask8ooklast chapterN

no let/s put flask in ngin0

4etc4ngin$4sites8enaled4default

server D

listen HF defaultQ

server_name domain.comQ

server_name ###.domain.comQ

access_log /var/log/nginx/domain.com.access.logQ

root /home/your_)as%_pro$ectQ

location /static/ D

expires maxQ

add_header ;ast-Lodied `sent_http_CxpiresQ

alias /home/your_)as%_pro$ect/app/static/Q
https://www.digitalocean.com/community/tutorials/how-to-optimize-nginx-configurationhttps://www.digitalocean.com/community/tutorials/how-to-optimize-nginx-configurationhttps://github.com/AndreiD/FlaskBookhttp://www.domain.com/https://www.digitalocean.com/community/tutorials/how-to-optimize-nginx-configurationhttps://www.digitalocean.com/community/tutorials/how-to-optimize-nginx-configurationhttps://github.com/AndreiD/FlaskBookhttp://www.domain.com/


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G

location / D

try_les `uri tornadoQ

G

location tornado D

proxy_set_header 0ost `hostQ

proxy_set_header I-Veal-7: `remote_addrQ

proxy_set_header I-*or#arded-*or `proxy_add_x_for#arded_forQ

proxy_pass http"//.F.F.


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language can use to )onitor it; and an Q+9-RPC interface for control, :t is also built ith

e0tension points that can be le(eraged by Python de(elopers,

Co)patible

'uper(isor orks on Dust about e(erything e0cept for #indos, :t is tested and

supported on 9inu0; +ac =' Q; 'olaris; and Free8'., :t is ritten entirely in Python; so

installation does not reuire a C co)piler,Pro(en

#hile 'uper(isor is (ery acti(ely de(eloped today; it is not ne softare, 'uper(isor has

been around for years and is already in use on )any ser(ers,

#ote that: Supervisor will not run at all under any version of %indows.

let/s no insert our progra) into super(isor, Ter)inate the app if you ha(e it running and

4etc4supervisor4supervisord.conf

Q supervisor cong le

\unix_http_server]

le+/var/run/supervisor.soc% Q ,the path to the soc%et le

chmod+F>FF Q soc%ef le mode ,default F>FF

\supervisord]

logle+/var/log/supervisor/supervisord.log Q ,main log leQdefault

`81/supervisord.log

logle_max!ytes+SFLTpidle+/var/run/supervisord.pid Q ,supervisord pidleQdefault supervisord.pid

childlogdir+/var/log/supervisor Q ,KJ9 child log dir@ default `9CL:

Q the !elo# section must remain in the cong le for V:8

Q ,supervisorctl/#e! interface to #or%@ additional interfaces may !e

Q added !y dening them in separate rpcinterface" sections

\rpcinterface"supervisor]

supervisor.rpcinterface_factory +

supervisor.rpcinterface"ma%e_main_rpcinterface

\supervisorctl]

serverurl+unix"///var/run/supervisor.soc% Q use a unix"// JV; for a unix soc%et

Q 9he \include] section can $ust contain the ?les? setting. 9his

Q setting can list multiple les ,separated !y #hitespace or

Q ne#lines. 7t can also contain #ildcards. 9he lenames are

Q interpreted as relative to this le. 7ncluded les ZcannotZ

Q include les themselves.


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\include]

les + /etc/supervisor/conf.d/Z.conf

Eprogram5mysuperappcommand0python homethe#path#to#your#pro+ectrun"py

stderr#logle 0 !arlogsuper!isormysuperapp-stderr"log

stdout#logle 0 !arlogsuper!isormysuperapp-stdout"log

autostart0true

autorestart0true

stdout#logle#maGbytes0HIJK

stderr#logle#maGbytes0HIJK

startsecs0B

startretries0,I

7f you #ant@ you can read more a!out supervisor cong at

http"//supervisord.org/conguration.html

You have so many users that your server can=t hold them X

find out here/s the bottleneck

check Flask-Cache for a nice ay to i)ple)ent caching in your app

split the logic into )ultiple ser(ers

ask for help on stacko(erflo,co)

see http,)a0cdn,co)

)oney are no proble) Get a *G8 27 CP5' *7G8 ''. .:'[ 6T8

TRAK'FER +=KT"9? J*7,77 fro) digitalocean,,,or 2; &\

Chapter 11 - Goin online

>y >ethod!

#hen it co)es to buying do)ain na)es : go ith na)echeaphttp,na)echeap,co)affO*73please use the link if you ant to say thanks for

this book>

1, 8uy a do)ain fro) na)echeap,

2, Get a HP' fro) digitalocean,co) httpgoo,glAr9(y0 )y referal link again and you

get J17 on your account after you )ake it>

&, Ko in your na)echeap do)ain )anager

+y Account+anage .o)ains+odify .o)ain
http://supervisord.org/configuration.htmlhttp://www.maxcdn.com/http://www.namecheap.com/?aff=64507http://goo.gl/ArLvyxhttp://goo.gl/ArLvyxhttps://manage.www.namecheap.com/myaccount/index.asphttps://manage.www.namecheap.com/myaccount/domain-list.asphttp://supervisord.org/configuration.htmlhttp://www.maxcdn.com/http://www.namecheap.com/?aff=64507http://goo.gl/ArLvyxhttps://manage.www.namecheap.com/myaccount/index.asphttps://manage.www.namecheap.com/myaccount/domain-list.asp


56/62

'pecify Custo) .K' 'er(ers ?our on .K' 'er(ers >

K'1,.:G:TA9=CEAK,C=+

K'2,.:G:TA9=CEAK,C=+

K'&,.:G:TA9=CEAK,C=+

*, Ko go to your digitalocean,co) dashboardcreate a ne droplet hile the )ini)u) droplet should be enough for start; get the

1GhI one if J per )onth is not too )uch for you>

Click the droplet,

Go to .K'

Fro) the top button click !Add .o)ain%

'elect the droplet fro) the left, The :P address should be added auto)atically

Enter the do)ain na)e E0 androidad(ance,co)>

Add an !A% record \ pointing to the droplet ip

_ \\\\\\\,, ipofthedroplet

Jthis might e already added for youM

Add a CKA+E

L,,,,,,,,,,,,,,,,,,,,,,,,,,,,, _

MoptionalN Add CKA+Es for a subdo)ainsubdo)ain,do)ain,co)\\\\\\\\\\,_

,$ample:


57/62

Ko login in your droplet; install super(isor; install ngin0; deploy your super flask app

etc,


58/62

Chapter 1 - A list o4 addons that )iht interest !ou

s;ipping the ones that we already used.

&las;8


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1, create a folder called utils, inside it create an e)pty file called init,py

this is called a package, and the init,py tells python that there are )odules to be

i)ported fro) this folder,

2, create colorstrea)handler,py

Google mooware 4 colorstreamhandler.py and copy-pate it fro) his gist.

Msidenote Gist is a si)ple ay to share snippets and pastes ith others, All gists are Git

repositories; so they are auto)atically (ersioned; forkable and usable fro) Git, ?ou can

create to kinds of gists public and pri(ate,

&, create generalutils,py

3 -Z- coding" utf-H -Z-

import logging

import logging.handlers

import colorstreamhandler

;6_*7;CPKLC + ../;8K97P/the_log.out

my_logger + logging.get;ogger,Ly;ogger

my_logger.set;evel,logging.CTJ6

le_handler + logging.handlers.Votating*ile0andler,;6_*7;CPKLC@

maxTytes+


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if category ++ ?error?"

my_logger.error,message

\edit the ;8K97P for ?the_log.out?]

3 -Z- coding" utf-H -Z-? is good if you #or% #ith russian@chineese characters.

?;6_*7;CPKLC + ../folder/the_log.out? si #here the_log.out #ill !e

Votating*ile0andler #ill %eep it small...so you dont end up #ith (FF6T log

les.

le_handler.set;evel,logging.CVVV - #e only log CVVV5 to the le

no# #e add another handler and set the logging level to P95C9 so #e see

everything in the console.

Po# #e call our log #ith"

/some_le.py

32/usr/!in/python

3-Z- coding" utf-H -Z-from utils import general_utils

general_utils.cool_log,?hello from error?@?error?

general_utils.cool_log,?hello from de!ug?@?de!ug?

you should see !oth messages displayed in color on your console. and $ust

the error message logged to le.

0ome#or%"

add time to the log in the le ,hint" use ?EB-Em-Ed E0"EL"E5? and level

name in the console display.


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le_handler.set*ormatter,logging.*ormatter,?E,asctimes 333 E

,messages?@ ?EB-Em-Ed E0"EL"E5?

stderr_log_handler.set*ormatter,logging.*ormatter,?E,levelnames 333 E

,messages?@ ?EB-Em-Ed E0"EL"E5?


62/62

Kfter you logged in to #e!min@ lets congure it to !e a!le to send us

notication mails.

1e!min 8onguration 5ending Cmail ,on the !ottom of the screen

8ongure ?5end email using?

Pote" 7 use sendgrid@ so 7 put [ia 5L9: to remote mail server

smtp.sendgrid.net port SH> and my username and pass#ord@ 5L9:

authentication method" ?;ogin?. Tut if you prefer another setting please

congure it.

ne of the most important things to do is !ac%up the data!ase. 0eres ho#"

pen Ly5U; ata!ase 5erver on servers ,or in unused modules

enter root and pass#ord

on the !ottom you have ?!ac%up data!ases? #ith all the nice options@

including 5cheduled !ac%up ena!led and sending mail in case the !ac%up

fails. 5#eet

:ro!lem. 7f you chose to ma%e !ac%up every day@ the #e!min over#rites the

les. 1e #ant to create a ne# folder everytime a !ac%up is done.

9o ena!le this return to the main mysql server module. 8lic% module cong

lin% ,upper part. 5et o strftime su!stitution of !ac%up destinationsb BC5

Po# in the !ac%up data!ase screen #rite the !ac%up folder #ith/home/!ac%ups/Ed-Em-EB/ ,example if you #ant daily !ac%ups. Po# each

time a !ac%up is done@ it #ill create a ne# folder.

Pote" in case your data!ase is a !ig one@ you might #ant to consider other

methods.

0ome#or%"

1e!min has lots of other cool things too. 8hec% ta! ?*ilesystem Tac%up? and

?5cheduled 8ron Mo!s?

Web Development With Python and Flask

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