Scalable applications with HTTP

Size: px

Start display at page:

Download "Scalable applications with HTTP"

Lorena Wheeler
6 years ago
Views:

1 Scalable applications with HTTP Patrice Neff, co-founder Memonic twitter.com/pneff memonic

2 Memonic Founded in 2009 Your personal digital notebook Easy web research Try it out for free:

3 About me Web developer Co-Founder Memonic Previously frontend developer at local.ch Details & Blog:

4 I ll talk about... Service-oriented architectures Motivation HTTP, the protocol Real-world architecture Code examples

5 Glossary Performance Scalability Prosper meters / hour pinkmoose 300 meters / hour

6 Service-oriented architectures Internet Internet Frontend DB Web Server Service 1 Service 2 Service 3

7 Key points Dependencies local to service Database Queue Synchronization Try the simplest service that works Services are the new classes? Internet Frontend Service 1 Service 2 Service 3

8 Motivation Modularity Team separation Clear boundaries Easier migrations / replacements Versioning Re-use of services Best tool for the job Programming language Dependencies (Database, Queue,...) Scalability Competence centre

9 Disadvantages Setup cost Complex full-picture view Performance Data joins Eddi 07

10 Disadvantages Setup cost Per company, not per project New tools help (e.g. WsgiService) Complex full-picture view Worse than usual? Performance More engineering work Caching But: consistent performance Data joins You shouldn t be doing this anyway Eddi 07

11 HTTP RFC 2616 defines HTTP 1.1 Text protocol Solved problems: Caching Compression Error handling Authentication Content negotiation Documentation

12 Bonus Also available: Load balancing Proxying Encryption

13 HTTP Example GET /intl/en/about.html HTTP/1.1 Host: HTTP/ OK Date: Wed, 24 Mar :51:06 GMT Expires: -1 Cache-Control: private, max-age=0 Content-Type: text/html; charset=iso Server: gws X-XSS-Protection: 0 <!doctype html>...

14 404 Slide Not Found NASA/CXC/SAO

15 Error handling 100 Continue 101 Switching Protocols 200 OK 201 Created 202 Accepted 203 Non-Authoritative Information 204 No Content 205 Reset Content 206 Partial Content 300 Multiple Choices 301 Moved Permanently 302 Found 303 See Other 304 Not Modified 305 Use Proxy 307 Temporary Redirect 400 Bad Request 401 Unauthorized 402 Payment Required 403 Forbidden 404 Not Found 405 Method Not Allowed 406 Not Acceptable 407 Proxy Authentication Required 408 Request Time-out 409 Conflict 410 Gone 411 Length Required 412 Precondition Failed 413 Request Entity Too Large 414 Request-URI Too Large 415 Unsupported Media Type 416 Requested range not satisfiable 417 Expectation Failed 500 Internal Server Error 501 Not Implemented 502 Bad Gateway 503 Service Unavailable 504 Gateway Time-out 505 HTTP Version not supported

16 Caching Cache-Control response header: Allow or prohibit caching Specify cache validity ETag response header: Client can validate it s cache content Avoids re-transmission of content

17 Caching Example GET /1/ HTTP/1.1 Host: geoip Accept: application/json HTTP/ OK Cache-Control: max-age= Expires: Fri, 25 Mar :28:44 GMT ETag: "content_stamp" Content-Type: application/json; charset=utf-8 Content-MD5: a59a841c05fdddef931399ef2275f6d3 {"country_code": "CH"}

18 Caching Validation Example GET /1/ HTTP/1.1 Host: geoip Accept: application/json If-None-Match: "content_stamp" HTTP/ Not Modified

19 Compression Accept-Encoding request header Content-Encoding response header

20 Compression Example GET /1/userid/huge_item HTTP/1.1 Host: storage Accept-Encoding: gzip HTTP/ OK Content-Type: text/xml Content-Length: 3860 Content-Encoding: gzip

21 Memonic Architecture Internet geoip staticpage Frontend browser index user label storage pipeline mime screenshot html_cleanup

22 Server example import logging import datetime import pygeoip from wsgiservice import * log = logging.getlogger( doc='the IP address to look up.', re='[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}') class IpResource(Resource): """Represents the GeoIP information of a single IP def GET(self, ip): """Return the country code for the given IP address.""" geoip = pygeoip.geoip() country_code = geoip.country_code_by_addr(ip) if not country_code: raise_404(self) log.debug("mapped IP %s to country code %s", ip, country_code) return {'country_code': country_code} app = get_app(globals())

23 Client example import json import httplib2 client = httplib2.http() response, content = client.request( ' 'GET', headers= {'Accept': 'application/json'}) assert int(response.status) < 400 info = json.loads(content) print "Country:", info['country_code']

24 Links or:

25 Thank you! Patrice Neff, co-founder Memonic twitter.com/pneff memonic

COMPUTER NETWORKS AND COMMUNICATION PROTOCOLS. Web Access: HTTP Mehmet KORKMAZ

COMPUTER NETWORKS AND COMMUNICATION PROTOCOLS Web Access: HTTP 16501018 Mehmet KORKMAZ World Wide Web What is WWW? WWW = World Wide Web = Web!= Internet Internet is a global system of interconnected computer