Class: Elastic::Transport::Client

Inherits:
Object
  • Object
show all
Includes:
MetaHeader
Defined in:
lib/elastic/transport/client.rb

Overview

Handles communication with an Elastic cluster.

See README for usage and code examples.

Constant Summary collapse

DEFAULT_TRANSPORT_CLASS = 
Transport::HTTP::Faraday
DEFAULT_LOGGER = 
lambda do
  require 'logger'
  logger = Logger.new(STDERR)
  logger.progname = 'elastic'
  logger.formatter = proc { |severity, datetime, progname, msg| "#{datetime}: #{msg}\n" }
  logger
end
DEFAULT_TRACER = 
lambda do
  require 'logger'
  logger = Logger.new(STDERR)
  logger.progname = 'elastic.tracer'
  logger.formatter = proc { |severity, datetime, progname, msg| "#{msg}\n" }
  logger
end
DEFAULT_HOST =

The default host and port to use if not otherwise specified.

Since:

  • 7.0.0

'localhost:9200'.freeze
DEFAULT_PORT =

The default port to use if not otherwise specified.

Since:

  • 7.2.0

9200

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from MetaHeader

#called_from?, #client_meta_version, #elasticsearch?, #enterprise_search?, #meta_header_adapter, #meta_header_engine, #meta_header_service_version, #set_meta_header

Constructor Details

#initialize(arguments = {}) {|faraday| ... } ⇒ Client

Create a client connected to an Elastic cluster.

Specify the URL via arguments or set the ‘ELASTICSEARCH_URL` environment variable.

Parameters:

  • arguments (Hash) (defaults to: {}) —

    a customizable set of options

  • enable_meta_header (Hash) —

    a customizable set of options

  • ca_fingerprint (Hash) —

    a customizable set of options

Options Hash (arguments):

  • :hosts (String, Array) —

    Single host passed as a String or Hash, or multiple hosts passed as an Array; ‘host` or `url` keys are also valid

  • :log (Boolean) —

    Use the default logger (disabled by default)

  • :trace (Boolean) —

    Use the default tracer (disabled by default)

  • :logger (Object) —

    An instance of a Logger-compatible object

  • :tracer (Object) —

    An instance of a Logger-compatible object

  • :resurrect_after (Number) —

    After how many seconds a dead connection should be tried again

  • :reload_connections (Boolean, Number) —

    Reload connections after X requests (false by default)

  • :randomize_hosts (Boolean) —

    Shuffle connections on initialization and reload (false by default)

  • :sniffer_timeout (Integer) —

    Timeout for reloading connections in seconds (1 by default)

  • :retry_on_failure (Boolean, Number) —

    Retry X times when request fails before raising and exception (false by default)

  • :delay_on_retry (Number) —

    Delay in milliseconds between each retry (0 by default)

  • Array (Number) —

    :retry_on_status Retry when specific status codes are returned

  • :reload_on_failure (Boolean) —

    Reload connections after failure (false by default)

  • :request_timeout (Integer) —

    The request timeout to be passed to transport in options

  • :adapter (Symbol) —

    A specific adapter for Faraday (e.g. ‘:patron`)

  • :transport_options (Hash) —

    Options to be passed to the ‘Faraday::Connection` constructor

  • :transport_class (Constant) —

    A specific transport class to use, will be initialized by the client and passed hosts and all arguments

  • :transport (Object) —

    A specific transport instance

  • :serializer_class (Constant) —

    A specific serializer class to use, will be initialized by the transport and passed the transport instance

  • :selector (Constant) —

    An instance of selector strategy implemented with Transport::Connections::Selector::Base.

  • :send_get_body_as (String) —

    Specify the HTTP method to use for GET requests with a body. (Default: GET)

  • :compression (true, false) —

    Whether to compress requests. Gzip compression will be used. The default is false. Responses will automatically be inflated if they are compressed. If a custom transport object is used, it must handle the request compression and response inflation.

Yields:

  • (faraday) —

    Access and configure the ‘Faraday::Connection` instance directly with a block



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# File 'lib/elastic/transport/client.rb', line 123

def initialize(arguments = {}, &block)
  @arguments = arguments.transform_keys(&:to_sym)
  @arguments[:logger] ||= @arguments[:log]   ? DEFAULT_LOGGER.call() : nil
  @arguments[:tracer] ||= @arguments[:trace] ? DEFAULT_TRACER.call() : nil
  @arguments[:reload_connections] ||= false
  @arguments[:retry_on_failure]   ||= false
  @arguments[:delay_on_retry]     ||= 0
  @arguments[:reload_on_failure]  ||= false
  @arguments[:randomize_hosts]    ||= false
  @arguments[:transport_options]  ||= {}
  @arguments[:http]               ||= {}
  @arguments[:enable_meta_header] = arguments.fetch(:enable_meta_header, true)

  @hosts ||= __extract_hosts(@arguments[:hosts] ||
                             @arguments[:host] ||
                             @arguments[:url] ||
                             @arguments[:urls] ||
                             ENV['ELASTICSEARCH_URL'] ||
                             DEFAULT_HOST)

  @send_get_body_as = @arguments[:send_get_body_as] || 'GET'
  @ca_fingerprint = @arguments.delete(:ca_fingerprint)

  if @arguments[:request_timeout]
    @arguments[:transport_options][:request] = { timeout: @arguments[:request_timeout] }
  end

  if @arguments[:transport]
    @transport = @arguments[:transport]
  else
    @transport_class = @arguments[:transport_class] || DEFAULT_TRANSPORT_CLASS
    @transport = if @transport_class == Transport::HTTP::Faraday
                   @arguments[:adapter] ||= __auto_detect_adapter
                   set_meta_header # from include MetaHeader
                   @transport_class.new(hosts: @hosts, options: @arguments) do |faraday|
                     faraday.adapter(@arguments[:adapter])
                     block&.call faraday
                   end
                 else
                   set_meta_header # from include MetaHeader
                   @transport_class.new(hosts: @hosts, options: @arguments)
                 end
  end

  if defined?(::OpenTelemetry) && ENV[OpenTelemetry::ENV_VARIABLE_ENABLED] != 'false'
    @otel = OpenTelemetry.new(@arguments)
  end
end

Instance Attribute Details

#transport ⇒ Object

Returns the transport object.

See Also:



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# File 'lib/elastic/transport/client.rb', line 61

def transport
  @transport
end

Instance Method Details

#perform_request(method, path, params = {}, body = nil, headers = nil, opts = {}) ⇒ Object

Performs a request through delegation to #transport.



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# File 'lib/elastic/transport/client.rb', line 174

def perform_request(method, path, params = {}, body = nil, headers = nil, opts = {})
  method = @send_get_body_as if 'GET' == method && body
  validate_ca_fingerprints if @ca_fingerprint
  if @otel
    # If no endpoint is specified in the opts, use the HTTP method name
    span_name = opts[:endpoint] || method
    @otel.tracer.in_span(span_name) do |span|
      span['http.request.method'] = method
      span['db.system'] = 'elasticsearch'
      opts[:defined_params]&.each do |k, v|
        if v.respond_to?(:join)
          span["db.elasticsearch.path_parts.#{k}"] = v.join(',')
        else
          span["db.elasticsearch.path_parts.#{k}"] = v
        end
      end
      if body_as_json = @otel.process_body(body, opts[:endpoint])
        span['db.statement'] = body_as_json
      end
      span['db.operation'] = opts[:endpoint] if opts[:endpoint]
      transport.perform_request(method, path, params || {}, body, headers)
    end
  else
    transport.perform_request(method, path, params || {}, body, headers)
  end
end