This gem extends the SWIG MapScript API of UMN MapServer with Ruby-like iterators and other API methods.
ruby_mapscript requires the MapScript API library to be installed. On Debian/Ubuntu systems:
sudo apt-get install libmapscript-ruby
A Mapserver binary (CGI) is not required for executing ruby_mapscript code.
To use the gem, add it to your Gemfile or install it manually:
gem install ruby_mapscript
To use ruby_mapscript, require the gem and include Mapscript in your class/module or globally:
require "rubygems" require "ruby_mapscript" include Mapscript
ruby_mapscript provides a Ruby-like iterator interface to MapScript collections:
map = MapObj.new('test.map') map.layers.each do |layer| puts layer.name end mapimage = map.draw mapimage.save('test.png')
With the generic SWIG API iterating would look like:
0.upto(map.numlayers-1) do |i| layer = map.getLayer(i) puts layer.name end
ruby_mapscript iterators include Enumerable which gives you the same methods as Ruby Arrays and Hashes:
wms_layers = map.layers.select { |layer| layer.connectiontype == MS_WMS }
To run a MapScript based WMS server as a Rack application create config.ru:
require "ruby_mapscript/mapserver" run RubyMapscript::Mapserver.new('test.map')
and call:
rackup config.ru
To include a WMS server in a Rails application, require "ruby_mapscript/mapserver" and add a line to your routes.rb:
match "/wms" => RubyMapscript::Mapserver.new('test.map')
If you get:
cannot load such file -- mapscript (LoadError)
when you run 'rake test' or try to use ruby_mapscript in a rails application, the following might solve the problem (on Debian/Ubuntu systems):
find where mapscript.so is hiding:
sudo updatedb locate mapscript.so
it could be something like:
/usr/lib/ruby/1.9.1/x86_64-linux/mapscript.so
add the path to your config/environment.rb, like this:
$: << '/usr/lib/ruby/1.9.1/x86_64-linux'
or add it to your Rakefile, like this:
Rake::TestTask.new do |t| t.libs << 'test' t.libs << '/usr/lib/ruby/1.9.1/x86_64-linux' # this line added end
Copyright (c) 2012 Pirmin Kalberer, Sourcepole AG