Python Code Camp for Professionals 1/4

Ingredients
• Python
• Web server framework
• Database
• Love

Bottle + GEvent
• Async is cool
• More efficientuse of CPU
• Best for I/O-boundapplications

Install Bottle + Gevent
pip install gevent
pip install bottle
easy_install gevent
easy_install bottle

Hello World
from gevent import monkey; monkey.patch_all()
from bottle import run, route
@route('/hello')
def fxn():
return "Hello World!"
run(server='gevent', host="localhost", port=8001, debug=True)

Step
Import gevent and bottle
Magicallyreplace synchronouslibrarieswith async
counterparts
from gevent import monkey;
monkey.patch_all()
from bottle import run, route

Step
Assign theurl /hello to thefunctionbelow
@route('/hello')
Define a pythonfunction
def fxn():
Return “HelloWorld!” to the browser
return "Hello World!"
Activate the gevent server, listen on port 8001
run(server='gevent', host="localhost", port=8001,
debug=True)

Accepting Inputs
Via theurl
http://www.gloopgroup.com/profile/paolo
Via query string
https://www.google.com.ph/?ion=1&q=gloopgroup
Via POSTbody
File upload to a website

Inputs in Bottle
Via theurl
@route('/input1/<name>')
def greet(name):
return "Hello "+name
Visit:localhost:8001/input1/paolo

Inputs in Bottle
Via query string
@route('/sum')
def sum():
total = 0
start = request.query.get("start")
end = request.query.get("end")
for i in range(start,end):
total += i
return "Sum of "+str(start) + " to " + str(end) + " = " +
str(total)
Visit: localhost:8001/sum?start=1&end=10

Inputs in Bottle
Via POST body
@route('/login', method="POST")
def login():
username = request.forms.get("username")
password = request.forms.get("password")
acceptedpasswords = ["gloopgroup", "devconph" ,
"adventuretime"]
if password in acceptedpasswords:
return "Welcome "+ username
else:
return "Unauthorized"
Visit: localhost:8001/login using login page

Activity 1
Create a calculatorapi:
http://localhost:8001/operation/operand1/operand2
will return the value of
operand1 <operation> operand2
Example:
/subtraction/10/2 will output 8

Common Return TYPES
PlainText
Similar to whatwe were doing earlier

Common Return TYPES
Binary
Whenreturning fileslike images, video, audio, pdfs…

Common Return TYPES
JSON
The common return type for APIs
Example:FB API
/{userid}/friends
{
"data": [
{
"name": "Terence Pua",
"id": "608407"
},
{
"name": "Gene Paul Quevedo",
"id": "10153785024974240"
},
{
"name": "Jc Velasquez",
"id": "722462218"
},
{
"name": "Jomel C. Imperio",
"id": "779287017"
}
],
"summary": {
"total_count": 770
}
}

Common Return TYPES
HTML
Returnweb pages with dynamic/static content
<!DOCTYPE html>
<html itemscope itemtype="http://schema.org/QAPage">
<head>
<title>regex - Validate email address in JavaScript? - Stack Overflow</title>
<link rel="shortcut icon" href="//cdn.sstatic.net/Sites/stackoverflow/img/favicon.ico?v=4f32ecc8f43d">
<link rel="apple-touch-icon image_src" href="//cdn.sstatic.net/Sites/stackoverflow/img/apple-touch-icon.png?v=c78bd457575a">
<link rel="search" type="application/opensearchdescription+xml" title="Stack Overflow" href="/opensearch.xml">
<meta name="twitter:card" content="summary">
<meta name="twitter:domain" content="stackoverflow.com"/>
<meta property="og:type" content="website" />
<meta property="og:image" itemprop="image primaryImageOfPage" content="http://cdn.sstatic.net/Sites/stackoverflow/img/apple-
touch-icon@2.png?v=73d79a89bded&a" />
<meta name="twitter:title" property="og:title" itemprop="title name" content="Validate email address in JavaScript?" />
<meta name="twitter:description" property="og:description" itemprop="description" content="How can an email address be validated
in JavaScript?" />
<meta property="og:url" content="http://stackoverflow.com/questions/46155/validate-email-address-in-javascript"/>
<link rel="canonical" href="http://stackoverflow.com/questions/46155/validate-email-address-in-javascript" />

Returning JSON Object
JSON
Simplyreturn a dictionary or list
@route("/json")
def jason():
return {"lastname":"bourne", "alias":"David Webb"}

Returning Static HTML
HTML
Use static_file from bottle
@route("/loginpage")
def loginpage():
return static_file("login.html", root=".")

Testing the POST Handler
Visit localhost:8081/loginpage
Type your nameand use any of theseas passwordg
gloopgroup, devconph, adventuretime
Click submit

The POST Request Cycle
<form action="/login" method="POST">
Method dictates what kind of request happens when submitted
Action tells the browser where to submit the request
<input type="text" name="username">
Adds a text input that will be associated to the username field
<input type="password" name="password">
Adds a password inputthat willbe associatedto the password field
<input type="submit">
Adds a button that submits the form whenclicked

Returning Dynamic HTML
HTML
Use a templatingengine:
• Library thatcan substitutevariables intoa templatequickly and cleanly
• Isolates thedesigner’s job of designing and thecoder’s job of coding

Install Tenjin
pip install tenjin
easy_install tenjin

Using Tenjin
monkey.patch_all()
from bottle import run, route, request
import tenjin
from tenjin.helpers import *
@route("/introduction/<name>/<age>/<work>")
def template1(name, age, work):
context = {"name":name, "age":age, "work":work}
return engine.render("introduction.html", context);
engine = tenjin.Engine(path=['.'])
run(server='gevent', host="localhost", port=8001, debug=True)

The template
<!doctype html>
<html lang="en">
<head>
<title>Login</title>
</head>
<body>
<h1>${name}</h1>
<h2>Age:${age}<h2>
<h2>Work:${work}<h2>
</body>
</html>

Step
monkey.patch_all()
from bottle import run, route, request
import tenjin
from tenjin.helpers import *
Import alllibraries, including tenjin and all helper methods
@route("/introduction/<name>/<age>/<work>")
Define a route for the url, and define variables in it
def template1(name, age, work):
Declare a request handler and receive the variables from the url

Step
context = {"name":name, "age":age, "work":work}
Define a context variable, which is a dictionary of values that will be substituted into the template
return engine.render("introduction.html", context);
Render the template called introduction.html using the context variable named context, and return it to
the browser
engine = tenjin.Engine(path=['.'])
Instructs the templating engine to look for the templates in the directories listed in path

Step (Inside the template)
<!doctype html>
<html lang="en">
<head>
<title>Login</title>
</head>
<body>
<h1>${name}</h1>
<h2>Age:${age}<h2>
<h2>Work:${work}<h2>
</body>
</html>
{
"name":"Paolo",
"age":"30",
"work":"Synergist"
}
+

Displaying Lists
@route("/spell/<word>")
def template1(word):
letters = list(word)
context = {"letters":letters, "word":word}
return engine.render("speller.html", context);

Step
@route("/spell/<word>")
Define a route that accepts a variable assigned to word
def speller(word):
Define a handler that accepts avariable named word
letters = list(word)
Convert the text string into a listobject. From a string “word”, it becomes a list [“w”, “o”, “r”, “d”]

Step
context = {"letters":letters}
Define a context variable, which contains the listof letters we just created
return engine.render("speller.html", context);
Render the template called speller.html using the context variable named context, and return it to the
browser

<?py for letter in letters: ?>
Loop on the elements of the list named letters
<h3>${letter}</h3><br>
Display the element letter along with the html
<?py #endfor ?>
Denote where the loop ends inthe template
<a href="/greet/${word}">greet ${word}</a>
Create a link that willcall the greet API we created earlier
{"letters":["s", "u", "s", "h", "i"]}

Highlighting Names
@route("/profiles/<name>")
def profile(name):
users = [
{"name":"Em", "image":"http://goo.gl/aDxeu1", "age":30,
"work":"Futurist"},
{"name":"Paolo", "image":"http://goo.gl/5k2oZr", "age":30,
"work":"Synergist"}
]
context = {"users":users, "name":name}
return engine.render("profiles.html", context)

Step
users = [
{"name":"Em", "image":"http://goo.gl/aDxeu1", "age":30, "work":"Futurist"},
{"name":"Paolo", "image":"http://goo.gl/5k2oZr", "age":30, "work":"Synergist"}
]
Define a list of dictionaries, with each dictionary objectcontaining information about a user. It contains information
name,url of the image, age, and work
context = {"users":users, "name":name}
Define a conext containing the name to behighlighted, and the list of users
return engine.render("profiles.html", context)
Render the template named profiles.html with the context

<?py for user in users: ?>
Loop on the elements of the list named users, each element in the listcan be referred to using the user
variable
<div style="height:100px;">
Create a div element in the html to contain one user element
<img src="${user['image']}" style="float:left;
height:100%;"/>
Place an image in the html coming from the url defined in user[‘image’]

<?py if name==user["name"]: ?>
Compare the current user’s name to the name entered in the url
<strong>Name: ${user['name']}</strong>
Thishappens when the above condition istrue, display the name asbold characters
<?py else: ?>
Add an else handler that executes if condition is not met

Name: ${user['name']}
This happens when primary condition is not met, display the user’s name without any decorations
<?py #endif ?>
Denote where the if statement ends

Make a Sushi Menu
Create a menu using allthe sushiitems in the sushilistvariable
Display the image and name of the sushi
When the menu item is clicked, it should display another page containingthe name, image, price, and
rating of the sushi(defined in the sushilistvariable)
The most creative presentation of the menu wins aprize

Activity 1
pip install gevent
pip install bottle

Cost per Mille =
• Cost per 1000 impressions
• Abuse of statistics
• i.e. Magic
• i.e. It sucks
• Not based on empirical measured data
ADVERTISING!
Eyeballs
cost

How many are watching
me right now?
How many are paying attention?
How many are interested?
How many are still reading this part?
How about now?
Now?

Python Code Camp for Professionals 1/4

ROUTER ON
PROMISCUOUS MODE
DEVICEs SENDING
PROBE REQUESTS

Pilot Installation
23000
Passers-by
39%
viewed
10%
Finished

Geofencing alternative
Detection
perimeter

turn off your phones
when going to the lagoon

Python Code Camp for Professionals 1/4

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