Ruben Verborgh RubenVerborgh

Accessing data through APIs

Update: my blog post The lie of the API details the issues with current APIs.

Background: I'm a researcher in semantic hypermedia, at the moment comparing different APIs for accessing metadata for human and machine consumption.

Story: I am browsing a cultural website and want to retrieve the metadata of the object I'm looking at in a machine-readable format. The steps below are the actual steps that I've undertaken on different sites.

Example: Cooper-Hewitt museum

I'm looking at the object http://collection.cooperhewitt.org/objects/35460799/.

	#!/usr/bin/env mocha --compilers coffee:coffee-script --reporter spec
	(require "mocha-as-promised")()
	chai = require "chai"
	Q = require "q"
	chai.should()
	chai.use require "chai-as-promised"
	chai.use require "chai-things"

	array = [{ a: 1 }, { b: 2 }]
	arrayPromise = Q.resolve(array)

	#!/usr/bin/env mocha --reporter spec --timeout 5000
	var chai = require("chai");
	var Q = require("q");
	chai.should();
	chai.use(require("chai-as-promised"));

	describe("The string", function() {
	it("should eventually be string", function() {
	'x'.should.be.a('string');
	});

	(function (chaiModule) {
	"use strict";
	// NodeJS
	if (typeof require === "function" && typeof exports === "object" && typeof module === "object")
	module.exports = chaiModule;
	// AMD
	else if (typeof define === "function" && define.amd)
	define(function () { return chaiModule; });
	// Other
	else

	\documentclass{sig-alternate-2013}

	% Fix for copyright block height
	\makeatletter
	\def\@copyrightlength{2.5} % Increase this value to leave more space above copyright notice
	\def\ftype@copyrightbox{8}
	\def\@copyrightspace{
	\@float{copyrightbox}[b]
	\begin{center}
	\setlength{\unitlength}{1pc}

	var request = require('request'),
	zlib = require('zlib');

	var headers = { 'Accept-Encoding': 'gzip' };

	var response = request({ url:'http://perdu.com/', headers: headers });
	response.on('response', function (response) {
	// decode the stream if necessary
	if (response.headers['content-encoding'] === 'gzip')
	response = response.pipe(zlib.createGunzip());

	\usepackage{xspace}
	\newcommand\Acronym[1]{%
	\expandafter\def\csname#1\endcsname{{\scshape #1}\xspace}%
	\expandafter\def\csname#1s\endcsname{{\scshape #1}s\xspace}%
	}
	\Acronym{api}
	\Acronym{rest}
	\Acronym{sparql}

	\sparql is not a \rest \api.

	# Without content negotiation, we get back an invalid content type
	$ curl -LI http://rdf.ebi.ac.uk/dataset/atlas/13.07
	HTTP/1.1 303 See Other
	Server: Apache/2.2.15 (Red Hat)
	Content-Type: text/html; charset=iso-8859-1
	Date: Wed, 04 Feb 2015 11:36:31 GMT
	Location: https://www.ebi.ac.uk/rdf/services/atlas/servlet/explore?uri=http://rdf.ebi.ac.uk/dataset/atlas/13.07
	Transfer-Encoding: chunked
	Connection: Keep-Alive

	PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
	PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
	PREFIX owl: <http://www.w3.org/2002/07/owl#>
	PREFIX skos: <http://www.w3.org/2004/02/skos/core#>
	PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
	PREFIX dc: <http://purl.org/dc/terms/>
	PREFIX dcterms: <http://purl.org/dc/terms/>
	PREFIX dc11: <http://purl.org/dc/elements/1.1/>
	PREFIX foaf: <http://xmlns.com/foaf/0.1/>
	PREFIX geo: <http://www.w3.org/2003/01/geo/wgs84_pos#>


	A. Resolving without leading ./ or ../
	BASE http://example.org/xxx/yyy/zzz, resolving aaa/bbb/ccc
	EYE http://example.org/xxx/yyy/aaa/bbb/ccc
	cwm http://example.org/xxx/yyy/aaa/bbb/ccc
	N3.js http://example.org/xxx/yyy/aaa/bbb/ccc
	Serd http://example.org/xxx/yyy/aaa/bbb/ccc

	B. Resolving with non-leading ./ or ../
	BASE http://example.org/xxx/yyy/zzz, resolving aaa/./bbb/ccc