Community Data Science Workshops (Spring 2014)/Saturday May 3rd lecture: Difference between revisions
Content added Content deleted
imported>Mako |
imported>Mako |
||
Line 45: | Line 45: | ||
#* navigate to [http://en.wikipedia.org/w/api.php api page] and show the documentation, point out examples |
#* navigate to [http://en.wikipedia.org/w/api.php api page] and show the documentation, point out examples |
||
#* looking at the images within a page http://en.wikipedia.org/w/api.php?action=query&titles=Seattle&prop=images&imlimit=20&format=jsonfm |
#* looking at the images within a page http://en.wikipedia.org/w/api.php?action=query&titles=Seattle&prop=images&imlimit=20&format=jsonfm |
||
#* change the city with a custom URL |
|||
#* looking at within two pages http://en.wikipedia.org/w/api.php?action=query&titles=Seattle|Bellevue,_Washington&prop=images&imlimit=50&format=jsonfm |
|||
#* (if time) parse through the output |
|||
#* edit count http://en.wikipedia.org/w/api.php?action=query&list=users&ususers=Benjamin_Mako_Hill|Jtmorgan|Sj|Mindspillage&usprop=editcount&format=jsonfm |
|||
#* |
#* (if time) edit count http://en.wikipedia.org/w/api.php?action=query&list=users&ususers=Benjamin_Mako_Hill|Jtmorgan|Sj|Mindspillage&usprop=editcount&format=jsonfm |
||
#* (if time) give me the content of the main page http://en.wikipedia.org/w/api.php?format=json&action=query&titles=Main%20Page&prop=revisions&rvprop=content |
|||
# Other APIs |
# Other APIs |
||
#* every API is different, so read the documentation! |
#* every API is different, so read the documentation! |
Revision as of 16:56, 3 May 2014
Lecture Outline
- Introduction to APIs
- definition of API: just an interface for programs
- definition of web API
- way to ask for data (almost always a URL)
- way to get data back (almost always in a format called JSON)
- every API is different, and documented
- to use APIs to build a dataset we will need:
- all our tools from last session: variables, etc
- the ability to open urls on the web
- the ability to create custom URLS
- the ability to save to files
- the ability to understand (i.e., parse) JSON data that APIs usually give us
- Review material from last session
- variables
- lists
- dictionaries
- if statements
- for loops
- printing
- modules
- New programming concepts:
- urllib2 and urlopen
- interpolate variables into a string using % and %()s
- open files and write to them
- placekitten.com
- API that takes specially crafted URLs and gives appropriately sized picture of kittens
- example of placekitten in browser
- visit the API documentation
- kittens of different sizes
- kittens in greyscale or color
- show how to use place
- write a small program to grab arbitrary square from placekitten by asking for the size on standard in
- JSON file (JavaScript Object Notation)
- what is json: useful for more structure data
- import json; json.loads()
- like Python (except no single quotes)
- simple lists, dictionaries
- can reflect more complicated data structures
- Example file at http://mako.cc/cdsw.json
- download it and parse it
- Wikipedia API
- explain MediaWiki, exists on other wikis
- navigate to api page and show the documentation, point out examples
- looking at the images within a page http://en.wikipedia.org/w/api.php?action=query&titles=Seattle&prop=images&imlimit=20&format=jsonfm
- change the city with a custom URL
- (if time) parse through the output
- (if time) edit count http://en.wikipedia.org/w/api.php?action=query&list=users&ususers=Benjamin_Mako_Hill%7CJtmorgan%7CSj%7CMindspillage&usprop=editcount&format=jsonfm
- (if time) give me the content of the main page http://en.wikipedia.org/w/api.php?format=json&action=query&titles=Main%20Page&prop=revisions&rvprop=content
- Other APIs
- every API is different, so read the documentation!
- for popular APIs, there are python modules that help you make requests and parse json!
- rate limiting
- authenticaiton
- text encoding issues