Class: Fluent::Plugin::HttpInput::Handler

Inherits:
Object
  • Object
show all
Defined in:
lib/fluent/plugin/in_http.rb

Constant Summary collapse

RES_200_STATUS = 
"200 OK".freeze
RES_403_STATUS = 
"403 Forbidden".freeze

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(io, km, callback, body_size_limit, format_name, log, cors_allow_origins, cors_allow_credentials, add_query_params) ⇒ Handler

Returns a new instance of Handler.



346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
 
# File 'lib/fluent/plugin/in_http.rb', line 346

def initialize(io, km, callback, body_size_limit, format_name, log,
               cors_allow_origins, cors_allow_credentials, add_query_params)
  @io = io
  @km = km
  @callback = callback
  @body_size_limit = body_size_limit
  @next_close = false
  @format_name = format_name
  @log = log
  @cors_allow_origins = cors_allow_origins
  @cors_allow_credentials = cors_allow_credentials
  @idle = 0
  @add_query_params = add_query_params
  @km.add(self)

  @remote_port, @remote_addr = io.remote_port, io.remote_addr
  @parser = Http::Parser.new(self)
end

Instance Attribute Details

#content_type ⇒ Object (readonly)

Returns the value of attribute content_type.



344
345
346
 
# File 'lib/fluent/plugin/in_http.rb', line 344

def content_type
  @content_type
end

Instance Method Details

#close ⇒ Object 



590
591
592
 
# File 'lib/fluent/plugin/in_http.rb', line 590

def close
  @io.close
end

#closing? ⇒ Boolean

Returns:

  • (Boolean) 


603
604
605
 
# File 'lib/fluent/plugin/in_http.rb', line 603

def closing?
  @next_close
end

#handle_get_request ⇒ Object

Azure App Service sends GET requests for health checking purpose. Respond with ‘200 OK` to accommodate it.



455
456
457
 
# File 'lib/fluent/plugin/in_http.rb', line 455

def handle_get_request
  return send_response_and_close(RES_200_STATUS, {}, "")
end

#handle_options_request ⇒ Object

Web browsers can send an OPTIONS request before performing POST to check if cross-origin requests are supported.



461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
 
# File 'lib/fluent/plugin/in_http.rb', line 461

def handle_options_request
  # Is CORS enabled in the first place?
  if @cors_allow_origins.nil?
    return send_response_and_close(RES_403_STATUS, {}, "")
  end

  # in_http does not support HTTP methods except POST
  if @access_control_request_method != 'POST'
    return send_response_and_close(RES_403_STATUS, {}, "")
  end

  header = {
    "Access-Control-Allow-Methods" => "POST",
    "Access-Control-Allow-Headers" => @access_control_request_headers || "",
  }

  # Check the origin and send back a CORS response
  if @cors_allow_origins.include?('*')
    header["Access-Control-Allow-Origin"] = "*"
    send_response_and_close(RES_200_STATUS, header, "")
  elsif include_cors_allow_origin
    header["Access-Control-Allow-Origin"] = @origin
    if @cors_allow_credentials
      header["Access-Control-Allow-Credentials"] = true
    end
    send_response_and_close(RES_200_STATUS, header, "")
  else
    send_response_and_close(RES_403_STATUS, {}, "")
  end
end

#include_cors_allow_origin ⇒ Object 



630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
 
# File 'lib/fluent/plugin/in_http.rb', line 630

def include_cors_allow_origin
  if @origin.nil?
    return false
  end

  if @cors_allow_origins.include?(@origin)
    return true
  end
  filtered_cors_allow_origins = @cors_allow_origins.select {|origin| origin != ""}
  r = filtered_cors_allow_origins.find do |origin|
    (start_str, end_str) = origin.split("*", 2)
    @origin.start_with?(start_str) && @origin.end_with?(end_str)
  end

  !r.nil?
end

#on_body(chunk) ⇒ Object 



440
441
442
443
444
445
446
447
448
 
# File 'lib/fluent/plugin/in_http.rb', line 440

def on_body(chunk)
  if @body.bytesize + chunk.bytesize > @body_size_limit
    unless closing?
      send_response_and_close("413 Request Entity Too Large", {}, "Too large")
    end
    return
  end
  @body << chunk
end

#on_close ⇒ Object 



369
370
371
 
# File 'lib/fluent/plugin/in_http.rb', line 369

def on_close
  @km.delete(self)
end

#on_headers_complete(headers) ⇒ Object 



386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
 
# File 'lib/fluent/plugin/in_http.rb', line 386

def on_headers_complete(headers)
  expect = nil
  size = nil

  if @parser.http_version == [1, 1]
    @keep_alive = true
  else
    @keep_alive = false
  end
  @env = {}
  @content_type = ""
  @content_encoding = ""
  headers.each_pair {|k,v|
    @env["HTTP_#{k.tr('-','_').upcase}"] = v
    case k
    when /\AExpect\z/i
      expect = v
    when /\AContent-Length\Z/i
      size = v.to_i
    when /\AContent-Type\Z/i
      @content_type = v
    when /\AContent-Encoding\Z/i
      @content_encoding = v
    when /\AConnection\Z/i
      if /close/i.match?(v)
        @keep_alive = false
      elsif /Keep-alive/i.match?(v)
        @keep_alive = true
      end
    when /\AOrigin\Z/i
      @origin  = v
    when /\AX-Forwarded-For\Z/i
      # For multiple X-Forwarded-For headers. Use first header value.
      v = v.first if v.is_a?(Array)
      @remote_addr = v.split(",").first
    when /\AAccess-Control-Request-Method\Z/i
      @access_control_request_method = v
    when /\AAccess-Control-Request-Headers\Z/i
      @access_control_request_headers = v
    end
  }
  if expect
    if expect == '100-continue'.freeze
      if !size || size < @body_size_limit
        send_response_nobody("100 Continue", {})
      else
        send_response_and_close("413 Request Entity Too Large", {}, "Too large")
      end
    else
      send_response_and_close("417 Expectation Failed", {}, "")
    end
  end
end

#on_message_begin ⇒ Object 



382
383
384
 
# File 'lib/fluent/plugin/in_http.rb', line 382

def on_message_begin
  @body = ''
end

#on_message_complete ⇒ Object 



492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
 
# File 'lib/fluent/plugin/in_http.rb', line 492

def on_message_complete
  return if closing?

  if @parser.http_method == 'GET'.freeze
    return handle_get_request()
  end

  if @parser.http_method == 'OPTIONS'.freeze
    return handle_options_request()
  end

  # CORS check
  # ==========
  # For every incoming request, we check if we have some CORS
  # restrictions and allow listed origins through @cors_allow_origins.
  # If origin is empty, it's likely a server-to-server request and considered safe.
  unless @cors_allow_origins.nil?
    unless @cors_allow_origins.include?('*') || include_cors_allow_origin || @origin.nil?
      send_response_and_close(RES_403_STATUS, {'Connection' => 'close'}, "")
      return
    end
  end

  # Content Encoding
  # =================
  # Decode payload according to the "Content-Encoding" header.
  # For now, we only support 'gzip' and 'deflate'.
  begin
    if @content_encoding == 'gzip'.freeze
      @body = Zlib::GzipReader.new(StringIO.new(@body)).read
    elsif @content_encoding == 'deflate'.freeze
      @body = Zlib::Inflate.inflate(@body)
    end
  rescue
    @log.warn 'fails to decode payload', error: $!.to_s
    send_response_and_close(RES_400_STATUS, {}, "")
    return
  end

  @env['REMOTE_ADDR'] = @remote_addr if @remote_addr

  uri = URI.parse(@parser.request_url)
  params = parse_query(uri.query)

  if @format_name != 'default'
    params[EVENT_RECORD_PARAMETER] = @body
  elsif /^application\/x-www-form-urlencoded/.match?(@content_type)
    params.update parse_query(@body)
  elsif @content_type =~ /^multipart\/form-data; boundary=(.+)/
    boundary = WEBrick::HTTPUtils.dequote($1)
    params.update WEBrick::HTTPUtils.parse_form_data(@body, boundary)
  elsif /^application\/json/.match?(@content_type)
    params['json'] = @body
  elsif /^application\/csp-report/.match?(@content_type)
    params['json'] = @body
  elsif /^application\/msgpack/.match?(@content_type)
    params['msgpack'] = @body
  elsif /^application\/x-ndjson/.match?(@content_type)
    params['ndjson'] = @body
  end
  path_info = uri.path

  if (@add_query_params)

    query_params = parse_query(uri.query)

    query_params.each_pair {|k,v|
      params["QUERY_#{k.tr('-','_').upcase}"] = v
    }
  end

  params.merge!(@env)

  @env.clear

  code, header, body = @callback.call(path_info, params)
  body = body.to_s
  header = header.dup if header.frozen?

  unless @cors_allow_origins.nil?
    if @cors_allow_origins.include?('*')
      header['Access-Control-Allow-Origin'] = '*'
    elsif include_cors_allow_origin
      header['Access-Control-Allow-Origin'] = @origin
      if @cors_allow_credentials
        header["Access-Control-Allow-Credentials"] = true
      end
    end
  end

  if @keep_alive
    header['Connection'] = 'Keep-Alive'.freeze
    send_response(code, header, body)
  else
    send_response_and_close(code, header, body)
  end
end

#on_read(data) ⇒ Object 



373
374
375
376
377
378
379
380
 
# File 'lib/fluent/plugin/in_http.rb', line 373

def on_read(data)
  @idle = 0
  @parser << data
rescue
  @log.warn "unexpected error", error: $!.to_s
  @log.warn_backtrace
  @io.close
end

#on_write_complete ⇒ Object 



594
595
596
 
# File 'lib/fluent/plugin/in_http.rb', line 594

def on_write_complete
  @io.close if @next_close
end

#parse_query(query) ⇒ Object 



647
648
649
 
# File 'lib/fluent/plugin/in_http.rb', line 647

def parse_query(query)
  query.nil? ? {} : Hash[URI.decode_www_form(query, Encoding::ASCII_8BIT)]
end

#send_response(code, header, body) ⇒ Object 



607
608
609
610
611
612
613
614
615
616
617
618
619
 
# File 'lib/fluent/plugin/in_http.rb', line 607

def send_response(code, header, body)
  header['Content-Length'] ||= body.bytesize
  header['Content-Type'] ||= 'text/plain'.freeze

  data = %[HTTP/1.1 #{code}\r\n]
  header.each_pair {|k,v|
    data << "#{k}: #{v}\r\n"
  }
  data << "\r\n".freeze
  @io.write(data)

  @io.write(body)
end

#send_response_and_close(code, header, body) ⇒ Object 



598
599
600
601
 
# File 'lib/fluent/plugin/in_http.rb', line 598

def send_response_and_close(code, header, body)
  send_response(code, header, body)
  @next_close = true
end

#send_response_nobody(code, header) ⇒ Object 



621
622
623
624
625
626
627
628
 
# File 'lib/fluent/plugin/in_http.rb', line 621

def send_response_nobody(code, header)
  data = %[HTTP/1.1 #{code}\r\n]
  header.each_pair {|k,v|
    data << "#{k}: #{v}\r\n"
  }
  data << "\r\n".freeze
  @io.write(data)
end

#step_idle ⇒ Object 



365
366
367
 
# File 'lib/fluent/plugin/in_http.rb', line 365

def step_idle
  @idle += 1
end