Read this stuff:

1. Read this stuff: http://www.smashingmagazine.com/2011/03/02/the-font-face-rule-revisited-and-useful-tricks/ http://diveintohtml5.org/geolocation.html http://css3.bradshawenterprises.com/#how2transforms http://jumbotron.media.mit.edu/

2. Services in PHP

3. Web Services • Web based applications • HTTP is the interface • Data is transmitted in XML or JSON • Generally intended for machine to machine communication • Required for mashups (generally)

4. HTTP • GET • Requests data from a server • POST • Sends data to a server • PUT • Pushes a file onto a server • DELETE • Asks server to delete a resource • HEAD • Gets http header back from server, not whole resource

5. HTTP Responses • 2xx = things are good • 200: OK, 201: created, 204: returning no content • 3xx = redirect • Head(‘location … causes 300 class HTTP response from your server

6. HTTP Responses • 4xx = client error • 401: unauthorized, 403: forbidden, 404: not found, 411: length required • 5xx = server error • 500: error, 501: not implemented, 503: Service Unavailable

7. Web Services… Service A HTTP XML HTTP Service B Client Host web server HTML Service C Database

8. AJAX Web Services… Service A HTTP JSON/XML/TEXT Client Side JS engine Service B DOM Client Host web server Service C HTML Database

9. An example • Load up this URL in your browser (add an address) • You could load this with simplexml_load_file() http://maps.google.com/maps/geo?q=<<your address here>>&output=xml&sensor=false

10. Web Service Flavors • SOAP • XML wrapper for HTTP data transfer • Can define any method (beyond Get, Post &c) • Lots of overhead • REST • Lighter than SOAP • Only supports HTTP methods • DAV • Focused on web as file system (HTTP as OS)

11. REST • Client gets a URL like example.com/products • Server sends back XML <products> <product id=‘1234’>A Chair</product> <product id=‘4958’>A Table</product> </products>

12. REST • Client gets a URL like example.com/products/1234 • Server sends back XML …. <product id=‘1234’> <cost units=‘us dollars’>45.00</cost> <color>green</color> </product>

13. REST • Imagine the whole data structure is in XML • (but really, we are just getting data out of any database) • Subfolders in the URL move in the complete pretend XML model like XPATH • Snippets of XML are returned • Examples: http://www.flickr.com/photos/blahblahblah/4355665120/ http://www.flickr.com/photos/96592303@N00/4387898659/sizes/l/

14. DAV • Extends HTTP to do file system operations • Lock • Unlock • Move • Copy • Mkcol – make collection • These operations take place on top of HTTP

15. DAV PUT example Using php CURL http://php.net/manual/en/book.curl.php

16. DAV PUT example Using php CURL http://php.net/manual/en/book.curl.php

17. GET / POST Examples • Generate your own HTTP requests from PHP to other servers/services: • Easy to use Basic HTTP auth between services http://php.net/manual/en/function.fsockopen.php

18. Listen for GET or POST • Apache/PHP Already does that! • Requests don’t have to come from web browsers • Get data via $_GET[‘varname’] and $_POST[‘varname’] • Output XML or JSON (or anything…but structure makes it easiest for the people using your web service)

19. Paypal posts to you • https://www.paypal.com/us/cgi-bin/webscr?cmd=p/pdn/ipn-codesamples-pop-outside • You post a request to paypal, it processes input, clears the transaction, and then posts a reply back to you.

20. JSON Java Script Object Notation

21. JSON is • A lightweight data interchange format • A replacement for XML • Human readable • Supports both hierarchical and unordered data • Supported by most programming languages • Supported by many modern web services • Flickr, Blogger, &c

22. Declaring a JSON object var mydata = {}; var mydata = new object{}

23. Name Value Pairs (unorderd) var js = {“runs” : “client”, “released” : 1995”, “type” : “scripting”};

24. Adding Depth varlang = { js : {“runs” : “client”, “released” : 1995”, “type” : “scripting”}, php: {“runs” : “server”, “released” : 1994”, “type” : “scripting”} };

25. Arrays (ordered data) var employers = { colleges : [“Sage”, “HVCC”, “RPI”] };

26. Nesting • Can nest • arrays in arrays • arrays in the value part of name/value pairs • blocks of name/value pairs inside the value part of name/value pairs • blocks of name/value pairs inside arrays

27. Access JSON Data • As an object var blah = lang.js.released; // blah = 1995 var blah = employers.colleges[1]; // blah = hvcc

28. Access JSON Data • As an associative array var blah = lang[“js”][“released”]; // blah = 1995 var blah = employers[“colleges”][1]; // blah = hvcc

29. Getting JSON Data • XmlHttpRequest GET • For JSON resources on your service • Call it from a script tag (within the src) • Used to get data from 3rd party services • Rewrite/reload script tag to get new data • Call backs……

30. Callback Functions • Returns a json object as the first argument of a function call • You write a function on your page to process json data • You request a json object and specify a callback function name • Service returns: callback_name(json_object) • Once script loads, function automatically runs

31. Callback Functions src = http://json.site.dom?callback=go Response would be: go({“blah” : [“blah”, blahblah, “blahblahblah”]});