class AzureEventHubsHttpSender

# File lib/fluent/plugin/azureeventhubs/http.rb, line 3
def initialize(connection_string, hub_name, expiry=3600,proxy_addr='',proxy_port=3128,open_timeout=60,read_timeout=60)
  require 'openssl'
  require 'base64'
  require 'unirest'
  require 'json'
  require 'cgi'
  require 'time'
  @connection_string = connection_string
  @hub_name = hub_name
  @expiry_interval = expiry
  @proxy_addr = proxy_addr
  @proxy_port = proxy_port
  @open_timeout = open_timeout
  @read_timeout = read_timeout

  if @connection_string.count(';') != 2
    raise "Connection String format is not correct"
  end

  @connection_string.split(';').each do |part|
    if ( part.index('Endpoint') == 0 )
      @endpoint = 'https' + part[11..-1]
    elsif ( part.index('SharedAccessKeyName') == 0 )
      @sas_key_name = part[20..-1]
    elsif ( part.index('SharedAccessKey') == 0 )
      @sas_key_value = part[16..-1]
    end
  end
  @uri = URI.parse("#{@endpoint}#{@hub_name}/messages")
end

# File lib/fluent/plugin/azureeventhubs/http.rb, line 46
def send(payload)
  send_w_properties(payload, nil)
end

# File lib/fluent/plugin/azureeventhubs/http.rb, line 50
  def send_w_properties(payload, properties)
    token = generate_sas_token(@uri.to_s)
    headers = {
      'Content-Type' => 'application/atom+xml;type=entry;charset=utf-8',
      'Authorization' => token
    }
    if not properties.nil?
      headers = headers.merge(properties)
    end
    Unirest.post @uri.request_uri, 
                        headers:{ 'Content-Type' => 'application/atom+xml;type=entry;charset=utf-8',
                            'Authorization' => token
                        }, 
                        parameters:payload {|response|
    response.code 
}   
  end

# File lib/fluent/plugin/azureeventhubs/http.rb, line 34
def generate_sas_token(uri)
  target_uri = CGI.escape(uri.downcase).downcase
  expiry = Time.now.to_i + @expiry_interval
  to_sign = "#{target_uri}\n#{expiry}";
  signature = CGI.escape(Base64.encode64(OpenSSL::HMAC.digest(OpenSSL::Digest.new('sha256'), @sas_key_value, to_sign)).strip())

  token = "SharedAccessSignature sr=#{target_uri}&sig=#{signature}&se=#{expiry}&skn=#{@sas_key_name}"
  return token
end