flickr.photos.astro.xml

<?xml version = "1.0"?>
<table xmlns = "http://query.yahooapis.com/v1/schema/table.xsd" >
  <meta >
    <author > Jim O 'Donnell</author>
    <documentationURL>http://eatyourgreens.org.uk/archives/2009/05/searching-the-sky-with-yql-execute.html</documentationURL>
    <sampleQuery description="Get up to 50 photos of M 42 (the Orion Nebula), starting at number 10.">select * from flickr.photos.astro(10,50) where astro_name='M 42'</sampleQuery>
  </meta>
  <bindings>
    <select produces="XML" itemPath="photos.photo">
      <urls>

        <url></url>
      </urls>
    <paging model="offset">
    <start id="start" default="0"/>
    <pagesize id="count" max="250"/>
    <total default="20"/>
    </paging>
      <inputs>
        <key id="text" type="xs:string" paramType="variable" />
        <key id="astro_name" type="xs:string" paramType="variable" />
        <key id="group_id" type="xs:string" paramType="variable" />
		<key id="api_key" type="xs:string" paramType="variable" />
      </inputs>
    <execute><![CDATA[
    var name_query = '';
	var api_query = '';
    if (text && text != '') name_query += " and text = '"+text.replace("'","\'")+"'";
	if (api_key && api_key != '') api_query = " and api_key = '"+api_key+"'";
    if (group_id && group_id != '') name_query += " and group_id = '"+group_id.replace("'","\'")+"'";
    var machine_tags = 'astro:RA=';
    if (astro_name && astro_name != '') machine_tags = 'astro:name="'+astro_name.replace("'","\'")+'"';

    var querystring = "select farm, server, id, secret, title, owner.username, urls.url.content, tags.tag.raw from flickr.photos.info where (tags.tag.raw like 'astro:%')"+api_query+" and photo_id in (select id from flickr.photos.search("+start+","+count+") where machine_tags='"+machine_tags+"'"+name_query+api_query+")";
    var data = y.query(querystring);
    var photos = parseAstrotags(data);

    default xml namespace = '';
    var respdata = <photos/>;
    for each (var photo in photos) {

      var node = <photo>
            <id>{photo.id}</id>
            <title>{photo.title}</title>
            <url>{photo.url}</url>
            <imgroot>{photo.imgroot}</imgroot>
            <username>{photo.username}</username>
            <ra>{photo.RA}</ra>
            <dec>{photo.Dec}</dec>
            <orientation>{photo.orientation}</orientation>
          </photo>;
      if(photo.fov) {
        node.photo += <fov>
                <x>{photo.fov.x}</x>
                <y>{photo.fov.y}</y>
              </fov>;

      }
      for(i=0; i<photo.name.length; i++) {
        node.photo += <name>{photo.name[i]}</name>;
      }
      respdata.photos += node;
    }
    
    // try extending cache time as these
    // results don't change very often.
    response.maxAge = 1800;
    response.object = respdata;
    
    function parseAstrotags(data) {

      var tag; 
      var tmp;
      var photo;
      var id;
      var o = {};
      o.id = '';
      var photos = [];

      /* Walk through the returned data and build an array of
      photos. */
      for each (var photo in data.results.photo) {
        id = photo.@['id'].toString();

        if (o.id != id) {
          o = {};
          photos.push(o);
          o['name'] = [];
          o['id'] = id;
          o['title']=photo.title.toString();
          o['url'] = photo.urls.url.toString();
          o['username'] = photo.owner.@['username'].toString();
          o['imgroot'] = 'http://farm'+photo.@['farm'].toString()+'.static.flickr.com/'+photo.@['server'].toString()+'/'+id+'_'+photo.@['secret'].toString();          
        }
        tag = photo.tags.tag.@['raw'].toString();
        //split machine tag name and value
        tmp = tag.split('=');
        //discard namespace from tag name by splitting tmp[0] on :
        // store data as o[id][predicate] = value eg. o[id].RA = 85.123456
        var tagname = tmp[0].split(':')[1];
        if (tagname == 'name') {
          o['name'].push(tmp[1]);
        } else {
          o[tagname] = tmp[1];
        }
        //fieldsize is a string in degrees, arcminutes or arcseconds.
        //We will standardise on a value in degrees.
        if (tmp[0] == 'astro:fieldsize') {
          //convert fieldsize string into a numeric value in degrees, using the width of the photo.
          tmp = o.fieldsize.split(' ');
          o.fov = {};
          o.fov.x = parseFloat(tmp[0]);
          o.fov.y = parseFloat(tmp[2]);
          if (tmp[3] == 'arcminutes') {
            o.fov.x = o.fov.x/60;
            o.fov.y = o.fov.y/60;
          }
          if (tmp[3] == 'arcseconds') {
            o.fov.x = o.fov.x/3600;
            o.fov.y = o.fov.y/3600;
          }
        }
      }

      return photos;
    }   
   ]]></execute>
    </select>
  </bindings>
</table>