Class: Quonfig::SSEConfigClient

Inherits:
Object
  • Object
show all
Defined in:
lib/quonfig/sse_config_client.rb

Defined Under Namespace

Classes: Options

Constant Summary collapse

LOG = 
Quonfig::InternalLogger.new(self)

Instance Method Summary collapse

Constructor Details

#initialize(prefab_options, config_loader, options = nil, logger = nil) ⇒ SSEConfigClient

Returns a new instance of SSEConfigClient.



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# File 'lib/quonfig/sse_config_client.rb', line 28

def initialize(prefab_options, config_loader, options = nil, logger = nil)
  @prefab_options = prefab_options
  @options = options || Options.new
  @config_loader = config_loader
  @connected = false
  @logger = logger || LOG
end

Instance Method Details

#close ⇒ Object 



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# File 'lib/quonfig/sse_config_client.rb', line 36

def close
  @retry_thread&.kill
  @client&.close
end

#connect(&load_configs) ⇒ Object 



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# File 'lib/quonfig/sse_config_client.rb', line 68

def connect(&load_configs)
  url = "#{source}/api/v2/sse/config"
  cursor = current_cursor
  @logger.debug "SSE Streaming Connect to #{url} start_at #{cursor.inspect}"

  SSE::Client.new(url,
                  headers: headers,
                  read_timeout: @options.sse_read_timeout,
                  reconnect_time: @options.sse_default_reconnect_time,
                  last_event_id: cursor,
                  logger: Quonfig::InternalLogger.new(SSE::Client)) do |client|
    client.on_event do |event|
      if event.data.nil? || event.data.empty?
        @logger.error "SSE Streaming Error: Received empty data for url #{url}"
        client.close
        next
      end

      begin
        parsed = JSON.parse(event.data)
      rescue JSON::ParserError => e
        @logger.error "SSE Streaming Error: Failed to parse JSON for url #{url}: #{e.message}"
        client.close
        next
      end

      envelope = Quonfig::ConfigEnvelope.new(
        configs: parsed['configs'] || [],
        meta: parsed['meta'] || {}
      )
      load_configs.call(envelope, event, :sse)
    end

    client.on_error do |error|
      # SSL "unexpected eof" is expected when SSE sessions timeout normally
      if error.is_a?(OpenSSL::SSL::SSLError) && error.message.include?('unexpected eof')
        @logger.debug "SSE Streaming: Connection closed (expected timeout) for url #{url}"
      else
        @logger.error "SSE Streaming Error: #{error.inspect} for url #{url}"
      end

      if @options.errors_to_close_connection.any? { |klass| error.is_a?(klass) }
        @logger.debug "Closing SSE connection for url #{url}"
        client.close
      end
    end
  end
end

#current_cursor ⇒ Object

Compute a Last-Event-ID to resume the stream from. Three sources, in priority order:

1. config_loader.version  -- string ETag from last HTTP fetch (new path)
2. config_loader.highwater_mark -- legacy numeric cursor
3. nil -- no prior state; stream from HEAD



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# File 'lib/quonfig/sse_config_client.rb', line 140

def current_cursor
  if @config_loader.respond_to?(:version)
    v = @config_loader.version
    return v if v.is_a?(String) && !v.empty?
  end

  if @config_loader.respond_to?(:highwater_mark)
    hw = @config_loader.highwater_mark
    return hw.to_s if hw.is_a?(Numeric) && hw.positive?
    return hw if hw.is_a?(String) && !hw.empty?
  end

  nil
end

#headers ⇒ Object 



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# File 'lib/quonfig/sse_config_client.rb', line 117

def headers
  auth = "1:#{@prefab_options.sdk_key}"
  auth_string = Base64.strict_encode64(auth)
  {
    'Authorization' => "Basic #{auth_string}",
    'Accept' => 'text/event-stream',
    'X-Quonfig-SDK-Version' => "ruby-#{Quonfig::VERSION}"
  }
end

#source ⇒ Object 



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# File 'lib/quonfig/sse_config_client.rb', line 127

def source
  @source_index = @source_index.nil? ? 0 : @source_index + 1

  @source_index = 0 if @source_index >= @prefab_options.sse_api_urls.size

  @prefab_options.sse_api_urls[@source_index]
end

#start(&load_configs) ⇒ Object 



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# File 'lib/quonfig/sse_config_client.rb', line 41

def start(&load_configs)
  if @prefab_options.sse_api_urls.empty?
    @logger.debug 'No SSE api_urls configured'
    return
  end

  @client = connect(&load_configs)

  closed_count = 0

  @retry_thread = Thread.new do
    loop do
      sleep @options.sleep_delay_for_new_connection_check

      next unless @client.closed?

      closed_count += @options.sleep_delay_for_new_connection_check

      next unless closed_count > @options.seconds_between_new_connection

      closed_count = 0
      @logger.debug 'Reconnecting SSE client'
      @client = connect(&load_configs)
    end
  end
end