A simple script to send event to event hub with SAS authentication

SendEventToEventHub.rb

require "optparse"
require "CGI"
require 'openssl'
require "base64"
require "Faraday"
require 'Digest'

def generateToken(url,keyname,keyvalue)
    encoded = CGI::escape(url)
    ttl = (Time.now + 60*5).to_i 
    signature = "#{encoded}\n#{ttl}"
    key = keyvalue
    #dig  = OpenSSL::HMAC.digest('sha256', key, signature)
    dig = Digest::HMAC.digest(signature, key, Digest::SHA256)
    hash = CGI.escape(Base64.strict_encode64(dig))
    # puts hash
    return "SharedAccessSignature sig=#{hash}&se=#{ttl}&skn=#{keyname}&sr=#{encoded}" 
end

def build_connection(url,token)
    conn = Faraday.new(:url => url) do |faraday|
        faraday.request  :url_encoded             # form-encode POST params
        faraday.response :logger                  # log requests to STDOUT
        faraday.adapter  Faraday.default_adapter  # make requests with Net::HTTP
    end
    conn.headers['Content-Type'] = 'application/json'
    conn.headers['Authorization'] = token
    return conn
end


if __FILE__ == $0
    ARGV << '-h' if ARGV.empty?
    options = {}
    OptionParser.new do |opts|
        opts.banner = "Usage: generateSasToken.rb [options]"
        opts.on('-u URL', '--url URL', 'url for access') { |v| options[:url] = v }
        opts.on('--keyname NAME','set key name') { |v| options[:keyname] = v }
        opts.on('--key KEY','set key value') { |v| options[:keyvalue] = v }
        opts.on_tail("-h", "--help", "Show this message") do
            puts opts
            exit
        end
    end.parse!
    token = generateToken(options[:url],options[:keyname],options[:keyvalue])
    conn = build_connection(options[:url],token)
    response =  conn.post do |req|
                    req.body = '{"temprature":50}'
                    req.headers['content-length'] = req.body.length.to_s
                end
    puts response
end