# A utility for signing an url using OAuth in a way that's convenient for debugging
# Note: the standard Ruby OAuth lib is here http://github.com/mojodna/oauth
# License: http://gist.github.com/375593
# Usage: see example.rb below
require 'uri'
require 'cgi'
require 'openssl'
require 'base64'
class OauthUtil
attr_accessor :consumer_key, :consumer_secret, :token, :token_secret, :req_method,
:sig_method, :oauth_version, :callback_url, :params, :req_url, :base_str
def initialize
@consumer_key = ''
@consumer_secret = ''
@token = ''
@token_secret = ''
@req_method = 'GET'
@sig_method = 'HMAC-SHA1'
@oauth_version = '1.0'
@callback_url = ''
@time
end
# openssl::random_bytes returns non-word chars, which need to be removed. using alt method to get length
# ref http://snippets.dzone.com/posts/show/491
def nonce
Array.new( 5 ) { rand(256) }.pack('C*').unpack('H*').first
end
def percent_encode( string )
# ref http://snippets.dzone.com/posts/show/1260
return URI.escape( string, Regexp.new("[^#{URI::PATTERN::UNRESERVED}]") ).gsub('*', '%2A')
end
# @ref http://oauth.net/core/1.0/#rfc.section.9.2
def signature
key = percent_encode( @consumer_secret ) + '&' + percent_encode( @token_secret )
# ref: http://blog.nathanielbibler.com/post/63031273/openssl-hmac-vs-ruby-hmac-benchmarks
digest = OpenSSL::Digest.new( 'sha1' )
hmac = OpenSSL::HMAC.digest( digest, key, @base_str )
# ref http://groups.google.com/group/oauth-ruby/browse_thread/thread/9110ed8c8f3cae81
Base64.encode64( hmac ).chomp.gsub( /\n/, '' )
end
# sort (very important as it affects the signature), concat, and percent encode
# @ref http://oauth.net/core/1.0/#rfc.section.9.1.1
# @ref http://oauth.net/core/1.0/#9.2.1
# @ref http://oauth.net/core/1.0/#rfc.section.A.5.1
def query_string
pairs = []
@params.sort.each { | key, val |
pairs.push( "#{ percent_encode( key ) }=#{ percent_encode( val.to_s ) }" )
}
pairs.join '&'
end
def header
'OAuth oauth_version="1.0",oauth_nonce="'+@nonce_now+'",oauth_timestamp="'+@time+'",oauth_consumer_key="'+@consumer_key+'",oauth_signature_method="'+@sig_method+'",oauth_signature="'+percent_encode(signature)+'"'
end
# organize params & create signature
def sign( parsed_url, query_param )
@time=Time.now.to_i.to_s
@nonce_now=nonce
@params = {
'format' => 'json',
'oauth_consumer_key' => @consumer_key,
'oauth_nonce' => @nonce_now,
'oauth_signature_method' => @sig_method,
'oauth_timestamp' => @time,
'oauth_version' => @oauth_version,
'q'=> query_param
}
# if url has query, merge key/values into params obj overwriting defaults
#if parsed_url.query
# @params.merge! CGI.parse( parsed_url.query )
#end
# @ref http://oauth.net/core/1.0/#rfc.section.9.1.2
@req_url = parsed_url.scheme + '://' + parsed_url.host + parsed_url.path
# create base str. make it an object attr for ez debugging
# ref http://oauth.net/core/1.0/#anchor14
@base_str = [
@req_method,
percent_encode(req_url),
# normalization is just x-www-form-urlencoded
percent_encode(query_string)
].join( '&' )
# add signature
return self
end
end