Creating GeoRSS with Ruby and REXML (2011-03-28)
GeoRSS on Google Maps:
-> Samurai zlash! - Google Maps
created GeoRSS file: 20110328_georss_sample.xml
source code:
#!/usr/bin/env ruby
$KCODE='u'
require 'time'
require "rexml/document"
def create_georss(channel, items)
doc = REXML::Document.new()
doc.add(REXML::XMLDecl.new(version="1.0", encoding="UTF-8"))
# <rss>
rss = REXML::Element.new("rss")
rss.add_attributes({
"version" => "2.0",
"xmlns:georss" => "http://www.georss.org/georss",
"xmlns:gml" => "http://www.opengis.net/gml",
"xmlns:geo" => "http://www.w3.org/2003/01/geo/wgs84_pos#",
})
doc.add_element(rss)
# <channel>
c = REXML::Element.new("channel", rss)
channel.each{|k,v|
if k == '_imageurl'
# logo image
image = REXML::Element.new('image', c)
REXML::Element.new('title', image).add_text(channel['title']) if channel['title']
REXML::Element.new('link', image).add_text(channel['link']) if channel['link']
REXML::Element.new('url', image).add_text(channel['_imageurl'])
else
# RFC2822 format
v = v.rfc2822() if v.kind_of?(Time)
REXML::Element.new(k, c).add_text(v)
end
}
# <item>
items.each{|item|
i = REXML::Element.new('item', c)
item.each{|k,a|
# ex. array of <category>
a = [a] if a.kind_of?(Array) == false
a.each{|v|
if k == '_geo'
# _geo is #{latitude},#{longitude}
latlon = v.split(',')
# 3 patterns : georss.org, GML, w3c
# GeoRSS-Simple
# xmlns:georss="http://www.georss.org/georss"
REXML::Element.new('georss:point', i).add_text(latlon[0] + ' ' + latlon[1])
# GeoRSS-GML
# xmlns:gml="http://www.opengis.net/gml"
where = REXML::Element.new('georss:where', i)
point = REXML::Element.new('gml:Point', where)
REXML::Element.new('gml:pos', point).add_text(latlon[0] + ' ' + latlon[1])
# WGS84 Geo Positioning
# xmlns:geo="http://www.w3.org/2003/01/geo/wgs84_pos#"
REXML::Element.new('geo:lat', i).add_text(latlon[0])
REXML::Element.new('geo:long', i).add_text(latlon[1])
else
# RFC2822 format
v = v.rfc2822() if v.kind_of?(Time)
REXML::Element.new(k, i).add_text(v)
end
}
}
}
str = ""
#formatter = REXML::Formatters::Default.new
formatter = REXML::Formatters::Pretty.new(2, true)
formatter.write(doc.root, str)
#doc.write(str, -1, true, true)
#doc.write(str, 2)
return str
end
# sample data
channel ={
'title' => 'Samurai zlash!',
'link' => 'http://www.nilab.info/zlash/',
'description' => 'Samurai Okojo.',
'copyright' => 'Copyright(c) 2000-2011 NI-Lab. All Right Reserved.',
'lastBuildDate' => Time.now,
'_imageurl' => 'http://www.nilab.info/zlash/samurai_okojo.jpg', # logo image url
}
items = [
{
'title' => 'I am hungry.',
'link' => 'http://www.nilab.info/zlash/hungry.html',
'description' => '<html><body>I am hungry.</body></html>',
'pubDate' => 'Tue, 14 Dec 2010 00:07:23 +0900',
'guid' => 'http://www.nilab.info/zlash/hungry.html',
'category' => 'food',
},
{
'title' => 'Do GeoRSS Dream of Electric Sheep?',
'link' => 'http://www.nilab.info/zlash/newyork.html',
'description' => '<html><body>I am sleepy... in New york.</body></html>',
'pubDate' => Time.local(2011, 1, 1, 11, 11, 11),
'guid' => 'http://www.nilab.info/zlash/newyork.html',
'category' => ['newyork', 'georss'],
'_geo' => '40.728340,-74.010360'
},
{
'title' => 'Great Lakes',
'link' => 'http://www.nilab.info/zlash/lakes.html',
'description' => '<html><body>Lake Erie, Lake Huron, Lake Michigan, Lake Ontario, Lake Superior</body></html>',
'pubDate' => Time.local(2011, 2, 3, 23, 59, 59),
'guid' => 'http://www.nilab.info/zlash/lakes.html',
'category' => ['lakes', 'georss', 'water'],
'_geo' => '45.949069,-84.062850'
},
]
run:
$ uname -mrsv
Linux 2.6.26-2-amd64 #1 SMP Tue Jan 25 05:59:43 UTC 2011 x86_64
$ ruby -v
ruby 1.8.7 (2008-08-11 patchlevel 72) [x86_64-linux]
$ date
Mon Mar 28 23:59:15 JST 2011
$ ruby ./ruby_rexml_georss.rb > 20110328_georss_sample.xml
Time.new.zone=JST
$ cat ./20110328_georss_sample.xml
<rss xmlns:georss='http://www.georss.org/georss' xmlns:gml='http://www.opengis.net/gml' xmlns:geo='http://www.w3.org/2003/01/geo/wgs84_pos#' version='2.0'>
<channel>
<title>
Samurai zlash!
</title>
<copyright>
Copyright(c) 2000-2011 NI-Lab. All Right Reserved.
</copyright>
<description>
Samurai Okojo.
</description>
<link>
http://www.nilab.info/zlash/
</link>
<image>
<title>
Samurai zlash!
</title>
<link>
http://www.nilab.info/zlash/
</link>
<url>
http://www.nilab.info/zlash/samurai_okojo.jpg
</url>
</image>
<lastBuildDate>
Mon, 28 Mar 2011 23:59:44 +0900
</lastBuildDate>
<item>
<category>
food
</category>
<guid>
http://www.nilab.info/zlash/hungry.html
</guid>
<pubDate>
Tue, 14 Dec 2010 00:07:23 +0900
</pubDate>
<title>
I am hungry.
</title>
<description>
<html><body>I am hungry.</body></html>
</description>
<link>
http://www.nilab.info/zlash/hungry.html
</link>
</item>
<item>
<category>
newyork
</category>
<category>
georss
</category>
<guid>
http://www.nilab.info/zlash/newyork.html
</guid>
<pubDate>
Sat, 01 Jan 2011 11:11:11 +0900
</pubDate>
<title>
Do GeoRSS Dream of Electric Sheep?
</title>
<description>
<html><body>I am sleepy... in New
york.</body></html>
</description>
<link>
http://www.nilab.info/zlash/newyork.html
</link>
<georss:point>
40.728340 -74.010360
</georss:point>
<georss:where>
<gml:Point>
<gml:pos>
40.728340 -74.010360
</gml:pos>
</gml:Point>
</georss:where>
<geo:lat>
40.728340
</geo:lat>
<geo:long>
-74.010360
</geo:long>
</item>
<item>
<category>
lakes
</category>
<category>
georss
</category>
<category>
water
</category>
<guid>
http://www.nilab.info/zlash/lakes.html
</guid>
<pubDate>
Thu, 03 Feb 2011 23:59:59 +0900
</pubDate>
<title>
Great Lakes
</title>
<description>
<html><body>Lake Erie, Lake Huron, Lake Michigan, Lake
Ontario, Lake Superior</body></html>
</description>
<link>
http://www.nilab.info/zlash/lakes.html
</link>
<georss:point>
45.949069 -84.062850
</georss:point>
<georss:where>
<gml:Point>
<gml:pos>
45.949069 -84.062850
</gml:pos>
</gml:Point>
</georss:where>
<geo:lat>
45.949069
</geo:lat>
<geo:long>
-84.062850
</geo:long>
</item>
</channel>
</rss>
Posted by NI-Lab. (@nilab)
