Sunny Portal signature generation method

gistfile1.rb

require "openssl"
require "base64"
require "cgi"

class SunnyPortal

  def initialize
    @api_service = "plantlist"
    @key         = ENV["KEY"]
    @identifier  = ENV["IDENTIFIER"]
    @http_method = "GET"
    @timestamp   = DateTime.now.utc.strftime("%FT%T")
  end

  def signature
    sig_string               = @http_method.downcase + @api_service.downcase + @timestamp + @identifier.downcase
    hmac_hash                = OpenSSL::HMAC.digest("sha1", @key, sig_string)
    base64_encoded_signature = Base64.strict_encode64(hmac_hash)

    CGI::escape(base64_encoded_signature)
  end

end

http://www.sunnyportal.com API signature generation
C# implementation: https://gist.github.com/query-string/fe9f33e1abea73dd1b1d