Add command line interface.

bin/geocode

+#!/usr/bin/env ruby
+
+require 'geocoder/cli'
+
+Geocoder::Cli.run ARGV

geocoder.gemspec

@@ -12,4 +12,5 @@ Gem::Specification.new do |s|
   s.description = "Provides object geocoding (by street or IP address), reverse geocoding (coordinates to street address), and distance queries for ActiveRecord and Mongoid. Designed for Rails but works with other Rack frameworks too."
   s.files       = `git ls-files`.split("\n") - %w[geocoder.gemspec Gemfile init.rb]
   s.require_paths = ["lib"]
+  s.executables = ["geocode"]
 end

lib/geocoder/cli.rb

+require 'geocoder'
+require 'optparse'
+
+module Geocoder
+  class Cli
+
+    def self.run(args, out = STDOUT)
+      url_only = false
+
+      OptionParser.new{ |opts|
+        opts.banner = "Usage:\n    geocode [options] location"
+        opts.separator "\nOptions: "
+
+        opts.on("-k <key>", "--key <key>",
+          "Key for geocoding API (optional for most)") do |key|
+          Geocoder::Configuration.api_key = key
+        end
+
+        opts.on("-l <language>", "--language <language>",
+          "Language of output (see API docs for valid choices)") do |language|
+          Geocoder::Configuration.language = language
+        end
+
+        lookups = Geocoder.valid_lookups - [:freegeoip]
+        opts.on("-s <service>", lookups, "--service <service>",
+          "Geocoding service: #{lookups.join(', ')}") do |service|
+          Geocoder::Configuration.lookup = service.to_sym
+        end
+
+        opts.on("-t <seconds>", lookups, "--timeout <seconds>",
+          "Maximum number of seconds to wait for API response") do |timeout|
+          Geocoder::Configuration.timeout = timeout.to_i
+        end
+
+        opts.on("-u", "--url", "Print URL for API instead of result") do
+          url_only = true
+        end
+
+        opts.on_tail("-v", "--version", "Print version number") do
+          puts "Geocoder #{Geocoder.version}"
+          exit
+        end
+
+        opts.on_tail("-h", "--help", "Print this help") do
+          puts opts
+          exit
+        end
+      }.parse!(args)
+
+      query = args.join(" ")
+
+      if query == ""
+        out << "Please specify a location to search for.\n"
+        exit 1
+      end
+
+      if url_only
+        out << Geocoder.send(:lookup).send(:query_url, query) + "\n"
+        exit 0
+      end
+
+      if (result = Geocoder.search(query).first)
+        out << result.coordinates.join(',') + "\n"
+        out << result.address + "\n"
+        exit 0
+      else
+        out << "Location '#{query}' not found.\n"
+        exit 2
+      end
+    end
+  end
+end