JSON

Beispiel: The Geotagger’s world atlas, Flickr: geodata, Mapbox: map
Explanation: citylab.
von Andreas Pirchner

		
import peasy.*;
PeasyCam cam; 

JSONObject fJSON;
JSONArray fItems;
JSONObject singleItem;
JSONObject link;
ArrayList urls = new ArrayList();
ArrayList pics = new ArrayList();
float radius = 600;


void setup(){
  size(690, 400, P3D);
  cam = new PeasyCam(this, 0);
  fJSON = loadJSONObject("https://api.flickr.com/services/feeds/photos_public.gne?tags=nasa+launch&format;=json&nojsoncallback;=1");
  fItems = fJSON.getJSONArray("items");
  
  for (int i = 0; i < fItems.size(); i++){
    singleItem = fItems.getJSONObject(i);
    link = singleItem.getJSONObject("media");
    String s = link.getString("m");
    urls.add(new String(s));
    PImage p = loadImage(s);
    pics.add(p);
  }
}

void draw(){
  background(10,10,30);
  drawPics();
}

void drawPics(){
  float angle = 0;
  for (int i = 0; i < fItems.size(); i++){
     float stepSize = TWO_PI / fItems.size();      // set stepsize for rotation
     angle = i*stepSize;
     float px = 0 + (radius * cos(angle));
     float py = 0 ;
     float pz = 0 + (radius * sin(angle));
     PImage p = pics.get(i);
    
     pushMatrix();
     translate(px, py, pz);
     rotateY(-angle+PI/2);
     tint(150,150,255,255);
     image(p, 0, 0);
     popMatrix();
  }
}

Komplexere Datenanfragen bei Flickr sind möglich, erfordern jedoch einen Authentifizierungsschlüssel (API-Schlüssel). Diesen Schlüssel erhält man normalerweise vom Datenanbieter, manchmal leichter, manchmal schwieriger.

What are API-Keys?

"An application programming interface key (API key) is a code passed in by computer programs calling an application programming interface (API) to identify the calling program, its developer, or its user to the Web site. API keys are used to track and control how the API is being used, for example to prevent malicious use or abuse of the API (as defined perhaps by terms of service). The API key often acts as both a unique identifier and a secret token for authentication, and will generally have a set of access rights on the API associated with it." (wikipedia.org)

Example 2: Search the NY Times (using an API-Key)

First we have to get an API-Key for authentification.
Then we need to study the available parameters for our search: here

Code-Example: Conneting to the NY Times

JSONObject timesJSON;

String timesURL = "https://api.nytimes.com/svc/search/v2/articlesearch.json";
String apiKey = "5824ca6412e04214a75bedf771b25dd0";

void setup(){
size(690, 400);
background(255);
timesJSON = loadJSONObject(timesURL + "?q=Algorithm?page=0&api-key;=" + apiKey);

println(timesJSON);

}

void draw(){

}

Exercise (30 Minutes):
Get your own API-Key for the NY Times API.
Take to code from above and search for a term (you can chose it yourself).
Visualize the amount of hits and publishing date (e.g. per year) for your term from the JSON response. Remember the difference between JSONObject and JSONArray.