Post on 16-Apr-2017
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Flask Tutorial - Step by Step
CLIENT - SERVER
SERVERCLIENT
Our Flask webapp
SERVERCLIENT
Our Flask webapp
Client Request
SERVERCLIENT
Our Flask webapp
Client Request
Server Response
CLIENT SERVER
Our Flask webapp
Client Request
Server Response
Flask Tutorial - Step by Step
HTTP
Flask Tutorial - Step by Step
🙌 HTTP 🙌
HTTP
HTTP is a stateless, text-based protocol
SERVERCLIENT
Our Flask webapp🤔
GET /intro-to-python HTTP/1.1Host: rmotr.comAccept: text/html
Example: Browsing http://rmotr.com
Client Request
SERVERCLIENT
Our Flask webapp
Client RequestGET /intro-to-python
HTTP/1.1
Client RequestGET /intro-to-python
HTTP/1.1
PATH
Client RequestGET /intro-to-python
HTTP/1.1
HTTP VERSION
Client RequestGET /intro-to-python
HTTP/1.1
HTTP METHOD
HTTP MethodsGET /intro-to-python
HTTP/1.1POST: Create resourcePUT: Update resourcePATCH: Update resourceDELETE: Delete resourceHEAD: ExtrasOPTIONS: Extras
Client Request
GET /tweet/3123 HTTP/1.1POST /tweet HTTP/1.1DELETE /tweet/3123 HTTP/1.1
Client Request
SERVERCLIENT
Our Flask webapp
Server Response
HTTP/1.1 200 OK
<html> <h1>Introduction to Python Programming</h1></html>
Server Response
HTTP/1.1 200 OK
<html> <h1>Introduction to Python Programming</h1></html>
Server Response
HTTP VERSION
HTTP/1.1 200 OK
<html> <h1>Introduction to Python Programming</h1></html>
Server Response
BODY
HTTP/1.1 200 OK
<html> <h1>Introduction to Python Programming</h1></html>
Server ResponseSTATUS CODE
STATUS CODES2XX: SUCCESS3XX: REDIRECTION4XX: CLIENT ERROR5XX: SERVER ERROR
EXAMPLE
bit.ly/rmotr-flask-tutorial
CLIENT
rmotr.com
GET /rmotr-flask-tutorial HTTP/1.1Host: bit.ly
CLIENT
rmotr.com
GET /rmotr-flask-tutorial HTTP/1.1Host: bit.ly
HTTP/1.1 301 Moved PermanentlyLocation: rmotr.com
CLIENT
rmotr.com
GET /rmotr-flask-tutorial HTTP/1.1Host: bit.ly
HTTP/1.1 301 Moved PermanentlyLocation: rmotr.com
HTTP/1.1 400 Bad Request
OTHER EXAMPLES
POST /tweet HTTP/1.1
HTTP/1.1 404 Not Found
OTHER EXAMPLES
GET /XYZ HTTP/1.1
https://en.wikipedia.org/wiki/List_of_HTTP_status_codes
MORE STATUS CODES
Flask Tutorial - Step by Step
HTTP HEADERS
Headers will allow Clients and Servers to include additional information
HTTP HEADERS
HTTP HEADERS
Can be included in Requests and Responses
GET /intro-to-python HTTP/1.1Host: rmotr.comUser-Agent: Mozilla/5.0Accept: text/htmlAccept-Encoding: gzip
Request with Headers
HTTP/1.1 200 OKServer: ApacheContent-Type: text/htmlContent-Length: 16824
Response with Headers
<html> <h1>rmotr.com</h1></html>