All files / lib _http_outgoing.js

97.2% Statements 1043/1073
96.81% Branches 334/345
98% Functions 49/50
97.2% Lines 1043/1073

Press n or j to go to the next uncovered block, b, p or k for the previous block.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 107411x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 455x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 53x 53x 53x 11x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 18403x 11x 11x 11x 11x 11x 41x 41x 41x 8x 41x 41x 11x 11x 11x 11x 1x 1x 11x 11x 11x 11x 11783x 11783x 11x 11x 11x 11x 3x 3x 11x 11x 11x 11x 8x 8x 8x 11x 11x 11x 11x 1x 11x 11x 2x 1x 1x 1x 1x 1x 1x 1x 2x 2x 2x 1x 11x 11x 11x 11x 11x 354x 11x 11x 1x 1x 11x 11x 11x 11x 2x 2x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 11x 11x 1x 1x 1x 1x                   11x 11x 11x 11x 11x 4x 1x 1x 3x 3x 3x 3x 4x 2x 2x 2x 2x 2x 2x 2x 2x 3x 11x 11x 11x 2x 2x 2x     11x 11x 11x 1x 1x 1x     11x 11x 11x 8x 8x 6x 6x 8x 8x 4x 2x 4x 4x 4x 4x 8x 11x 11x 11x 11x 11x 11x 11x 21x 1x 1x 20x 20x 21x 11x 21x 9x   9x 9x 20x 20x 11x 11x 11x 11x 11x 74753x 74753x 74753x 74753x 16533x 16533x 5267x 16514x 11266x 11266x 11266x 11266x 11266x 11266x 11266x 11266x 11266x 16533x 16533x 74753x 11x 11x 11x 11x 74760x 74760x 74760x 1x 1x 1x 1x 74759x 74760x 1x 1x 1x 74759x 74760x 37133x 37133x 39x 39x 37133x 37133x 37133x 37626x 37626x 37626x 37626x 37626x 74760x 11x 11x 11x 16536x 16536x 16536x 16536x 16536x 16536x 16536x 16536x 16536x 16536x 16536x 16536x 16536x 16536x 5268x 4255x 5360x 5360x 5360x 4470x 15x 13x 106x 106x 106x 15x 2x 1x 1x 1x 2x 2x 2x 1x 1013x 998x 1629x 1629x 1629x 1629x 995x 5268x 16532x 16532x 16532x 16532x 16536x 13567x 13567x 16532x 16532x 16532x 16532x 16532x 16532x 16532x 16532x 16532x 16532x 16532x 16532x 16536x 16536x 2x 2x 2x 2x 2x 16532x 16532x 16536x 1x 1x 16535x 16383x 16383x 16383x 3x 16381x 12290x 12290x 11778x 11778x 11778x 16377x 4090x 4090x 4090x 16383x 16532x 16536x 15257x 5x 5x 15254x 2909x 13283x 12343x 12343x 10634x 12327x 1708x 1708x 1709x 1x 1x 1x 1x 1x 15257x 16532x 16532x 16532x 16532x 16532x 16536x 1x 1x 16531x 16531x 16531x 16531x 16531x 16531x 16536x 16536x 11x 7097x 7097x 7097x 7097x 53x 53x 49x 53x 46x 46x 46x 46x 46x 46x 7x 7x 7051x 7097x 11x 7147x 7147x 7147x 7144x 7144x 7147x 11x 7144x 7144x 7144x 7005x 7005x 7144x 149x 149x 149x 149x 119x 119x 149x 7144x 7x 7x 7x 7x 7x 7144x 1271x 1271x 1271x 7144x 7144x 7144x 9x 9x 7144x 2x 2x 7144x 7144x 11x 11x 8247x 9x 9x 11x 11x 11x 7549x 4x 4x 7548x 5x 5x 5x 11x 11x 3414x 3414x 3412x 3412x 2x 2x 2x 2x 5x 5x 2x 2x 3414x 11x 11x 5396x 2x 2x 5394x 5394x 5394x 5394x 5394x 5395x 5383x 5383x 5383x 11x 11x 11x 4x     4x 4x 4x 4x 4x 4x     4x 4x 4x 1x 1x 4x 4x 4x 4x 8x 8x 4x     4x 4x 11x 11x 11x 11x 8854x 8854x 8854x 8854x 8854x 6131x 6131x 8854x 11x 11x 11x 11x 11x 8x 11x 11x 11x 11x 11x 7x 7x 6x 6x 6x 6x 6x 7x 17x 17x 6x 6x 11x 11x 11x 11x 11x 4x 4x 4x 3x 3x 3x 3x 12x 12x 12x 12x 3x 4x 11x 11x 11x 11x 13x 13x 13x 11x 11x 11x 11x 20x 20x 20x 1x 1x 18x 18x 18x 18x 20x 1x 1x 20x 1x 1x 20x 1x 1x 20x 8x 8x 20x 18x 19x 10x 10x 11x 11x 11x 11x 1x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 19x 19x 11x 11x 11x 11x 15486x 20x 20x 20x 15486x 15486x 15486x 15486x 15480x 11x 11x 4x 4x 4x 4x 4x 4x 4x 4x 4x 11x 4x 4x 4x 3x 3x 4x 11x 27536x 27536x 27536x 27536x 27536x 27536x 1x 27536x 14004x 27527x 13525x 13529x 6x 6x 6x 27529x 27529x 27535x 4x 27532x 2x 2x 27529x 27535x 6x 2x 6x 4x 4x 6x 6x 27523x 27526x 17269x 10511x 10511x 17269x 17269x 27522x 27529x 1x 1x 1x 1x 1x 27521x 27536x 766x 766x 766x 27521x 27521x 27536x 10243x 10243x 10243x 10243x 27512x 17278x 17278x 27521x 27521x 27521x 27536x 11x 11x 766x 766x 766x 11x 11x 10x 10x 10x 10x 10x 10x 17x 17x 17x 8x 8x 17x 9x 9x 9x 17x 1x 1x 16x 16x 16x 16x 17x 4x 17x 2x 4x       4x 4x 17x 14x 2x 2x 14x 14x 1x 1x 1x 13x 13x 17x 11x 11x 15656x 15656x 15648x 15656x 11x 11x 16525x 4x 4x 4x 16525x 10006x 10006x 10006x 16525x 16525x 12052x 2x 2x 2x 2x 2x 12050x 12050x 1983x 1983x 12050x 12050x 16525x 32x 2x   2x 2x 2x 2x 32x 4473x 3014x 130x 130x 3014x 3014x 3014x 3014x 16489x 16489x 16525x 16489x 16489x 16489x 16525x 1678x 15010x 14807x 14809x 4x 4x 16489x 16525x 2298x 2298x 2298x 2298x 16489x 16489x 16489x 16489x 16489x 16489x 16489x 16525x 16525x 16525x 2297x 2297x 16489x 16489x 11x 11x 11x 11x 15685x 15685x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 11x 16140x 16140x 16140x 16135x 16135x 16135x 16135x 13388x 13388x 13639x       16135x 11x 11x 11x 16174x       16174x 16174x 16174x 16174x 13448x 13448x 13448x 13448x 13448x 13448x 13717x 41092x 41092x 41092x 13448x 13448x 13448x 13448x 13448x 13448x 13448x 11x 11x 11x 11x 9x 5x 5x 9x 9x 9x 11x 11x 11x 1x 1x 11x 11x 11x 2x 2x 11x 11x 11x 11x 11x 11x 11x 11x 11x  
// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.
 
'use strict';
 
const {
  Array,
  ArrayIsArray,
  ArrayPrototypeJoin,
  MathFloor,
  NumberPrototypeToString,
  ObjectCreate,
  ObjectDefineProperty,
  ObjectKeys,
  ObjectValues,
  ObjectPrototypeHasOwnProperty,
  ObjectSetPrototypeOf,
  RegExpPrototypeTest,
  SafeSet,
  StringPrototypeToLowerCase,
  Symbol,
} = primordials;
 
const { getDefaultHighWaterMark } = require('internal/streams/state');
const assert = require('internal/assert');
const EE = require('events');
const Stream = require('stream');
const internalUtil = require('internal/util');
const { kOutHeaders, utcDate, kNeedDrain } = require('internal/http');
const { Buffer } = require('buffer');
const {
  _checkIsHttpToken: checkIsHttpToken,
  _checkInvalidHeaderChar: checkInvalidHeaderChar,
  chunkExpression: RE_TE_CHUNKED,
} = require('_http_common');
const {
  defaultTriggerAsyncIdScope,
  symbols: { async_id_symbol }
} = require('internal/async_hooks');
const {
  codes: {
    ERR_HTTP_HEADERS_SENT,
    ERR_HTTP_INVALID_HEADER_VALUE,
    ERR_HTTP_TRAILER_INVALID,
    ERR_INVALID_HTTP_TOKEN,
    ERR_INVALID_ARG_TYPE,
    ERR_INVALID_ARG_VALUE,
    ERR_INVALID_CHAR,
    ERR_METHOD_NOT_IMPLEMENTED,
    ERR_STREAM_CANNOT_PIPE,
    ERR_STREAM_ALREADY_FINISHED,
    ERR_STREAM_WRITE_AFTER_END,
    ERR_STREAM_NULL_VALUES,
    ERR_STREAM_DESTROYED
  },
  hideStackFrames
} = require('internal/errors');
const { validateString } = require('internal/validators');
const { isUint8Array } = require('internal/util/types');
 
let debug = require('internal/util/debuglog').debuglog('http', (fn) => {
  debug = fn;
});
 
const HIGH_WATER_MARK = getDefaultHighWaterMark();
 
const kCorked = Symbol('corked');
const kUniqueHeaders = Symbol('kUniqueHeaders');
 
const nop = () => {};
 
const RE_CONN_CLOSE = /(?:^|\W)close(?:$|\W)/i;
 
// isCookieField performs a case-insensitive comparison of a provided string
// against the word "cookie." As of V8 6.6 this is faster than handrolling or
// using a case-insensitive RegExp.
function isCookieField(s) {
  return s.length === 6 && StringPrototypeToLowerCase(s) === 'cookie';
}
 
function OutgoingMessage() {
  Stream.call(this);
 
  // Queue that holds all currently pending data, until the response will be
  // assigned to the socket (until it will its turn in the HTTP pipeline).
  this.outputData = [];
 
  // `outputSize` is an approximate measure of how much data is queued on this
  // response. `_onPendingData` will be invoked to update similar global
  // per-connection counter. That counter will be used to pause/unpause the
  // TCP socket and HTTP Parser and thus handle the backpressure.
  this.outputSize = 0;
 
  this.writable = true;
  this.destroyed = false;
 
  this._last = false;
  this.chunkedEncoding = false;
  this.shouldKeepAlive = true;
  this.maxRequestsOnConnectionReached = false;
  this._defaultKeepAlive = true;
  this.useChunkedEncodingByDefault = true;
  this.sendDate = false;
  this._removedConnection = false;
  this._removedContLen = false;
  this._removedTE = false;
 
  this._contentLength = null;
  this._hasBody = true;
  this._trailer = '';
  this[kNeedDrain] = false;
 
  this.finished = false;
  this._headerSent = false;
  this[kCorked] = 0;
  this._closed = false;
 
  this.socket = null;
  this._header = null;
  this[kOutHeaders] = null;
 
  this._keepAliveTimeout = 0;
 
  this._onPendingData = nop;
}
ObjectSetPrototypeOf(OutgoingMessage.prototype, Stream.prototype);
ObjectSetPrototypeOf(OutgoingMessage, Stream);
 
ObjectDefineProperty(OutgoingMessage.prototype, 'writableFinished', {
  get() {
    return (
      this.finished &&
      this.outputSize === 0 &&
      (!this.socket || this.socket.writableLength === 0)
    );
  }
});
 
ObjectDefineProperty(OutgoingMessage.prototype, 'writableObjectMode', {
  get() {
    return false;
  }
});
 
ObjectDefineProperty(OutgoingMessage.prototype, 'writableLength', {
  get() {
    return this.outputSize + (this.socket ? this.socket.writableLength : 0);
  }
});
 
ObjectDefineProperty(OutgoingMessage.prototype, 'writableHighWaterMark', {
  get() {
    return this.socket ? this.socket.writableHighWaterMark : HIGH_WATER_MARK;
  }
});
 
ObjectDefineProperty(OutgoingMessage.prototype, 'writableCorked', {
  get() {
    const corked = this.socket ? this.socket.writableCorked : 0;
    return corked + this[kCorked];
  }
});
 
ObjectDefineProperty(OutgoingMessage.prototype, '_headers', {
  get: internalUtil.deprecate(function() {
    return this.getHeaders();
  }, 'OutgoingMessage.prototype._headers is deprecated', 'DEP0066'),
  set: internalUtil.deprecate(function(val) {
    if (val == null) {
      this[kOutHeaders] = null;
    } else if (typeof val === 'object') {
      const headers = this[kOutHeaders] = ObjectCreate(null);
      const keys = ObjectKeys(val);
      // Retain for(;;) loop for performance reasons
      // Refs: https://github.com/nodejs/node/pull/30958
      for (let i = 0; i < keys.length; ++i) {
        const name = keys[i];
        headers[StringPrototypeToLowerCase(name)] = [name, val[name]];
      }
    }
  }, 'OutgoingMessage.prototype._headers is deprecated', 'DEP0066')
});
 
ObjectDefineProperty(OutgoingMessage.prototype, 'connection', {
  get: function() {
    return this.socket;
  },
  set: function(val) {
    this.socket = val;
  }
});
 
ObjectDefineProperty(OutgoingMessage.prototype, '_headerNames', {
  get: internalUtil.deprecate(function() {
    const headers = this[kOutHeaders];
    if (headers !== null) {
      const out = ObjectCreate(null);
      const keys = ObjectKeys(headers);
      // Retain for(;;) loop for performance reasons
      // Refs: https://github.com/nodejs/node/pull/30958
      for (let i = 0; i < keys.length; ++i) {
        const key = keys[i];
        const val = headers[key][0];
        out[key] = val;
      }
      return out;
    }
    return null;
  }, 'OutgoingMessage.prototype._headerNames is deprecated', 'DEP0066'),
  set: internalUtil.deprecate(function(val) {
    if (typeof val === 'object' && val !== null) {
      const headers = this[kOutHeaders];
      if (!headers)
        return;
      const keys = ObjectKeys(val);
      // Retain for(;;) loop for performance reasons
      // Refs: https://github.com/nodejs/node/pull/30958
      for (let i = 0; i < keys.length; ++i) {
        const header = headers[keys[i]];
        if (header)
          header[0] = val[keys[i]];
      }
    }
  }, 'OutgoingMessage.prototype._headerNames is deprecated', 'DEP0066')
});
 
 
OutgoingMessage.prototype._renderHeaders = function _renderHeaders() {
  if (this._header) {
    throw new ERR_HTTP_HEADERS_SENT('render');
  }
 
  const headersMap = this[kOutHeaders];
  const headers = {};
 
  if (headersMap !== null) {
    const keys = ObjectKeys(headersMap);
    // Retain for(;;) loop for performance reasons
    // Refs: https://github.com/nodejs/node/pull/30958
    for (let i = 0, l = keys.length; i < l; i++) {
      const key = keys[i];
      headers[headersMap[key][0]] = headersMap[key][1];
    }
  }
  return headers;
};
 
OutgoingMessage.prototype.cork = function() {
  if (this.socket) {
    this.socket.cork();
  } else {
    this[kCorked]++;
  }
};
 
OutgoingMessage.prototype.uncork = function() {
  if (this.socket) {
    this.socket.uncork();
  } else if (this[kCorked]) {
    this[kCorked]--;
  }
};
 
OutgoingMessage.prototype.setTimeout = function setTimeout(msecs, callback) {
 
  if (callback) {
    this.on('timeout', callback);
  }
 
  if (!this.socket) {
    this.once('socket', function socketSetTimeoutOnConnect(socket) {
      socket.setTimeout(msecs);
    });
  } else {
    this.socket.setTimeout(msecs);
  }
  return this;
};
 
 
// It's possible that the socket will be destroyed, and removed from
// any messages, before ever calling this.  In that case, just skip
// it, since something else is destroying this connection anyway.
OutgoingMessage.prototype.destroy = function destroy(error) {
  if (this.destroyed) {
    return this;
  }
  this.destroyed = true;
 
  if (this.socket) {
    this.socket.destroy(error);
  } else {
    this.once('socket', function socketDestroyOnConnect(socket) {
      socket.destroy(error);
    });
  }
 
  return this;
};
 
 
// This abstract either writing directly to the socket or buffering it.
OutgoingMessage.prototype._send = function _send(data, encoding, callback) {
  // This is a shameful hack to get the headers and first body chunk onto
  // the same packet. Future versions of Node are going to take care of
  // this at a lower level and in a more general way.
  if (!this._headerSent) {
    if (typeof data === 'string' &&
        (encoding === 'utf8' || encoding === 'latin1' || !encoding)) {
      data = this._header + data;
    } else {
      const header = this._header;
      this.outputData.unshift({
        data: header,
        encoding: 'latin1',
        callback: null
      });
      this.outputSize += header.length;
      this._onPendingData(header.length);
    }
    this._headerSent = true;
  }
  return this._writeRaw(data, encoding, callback);
};
 
 
OutgoingMessage.prototype._writeRaw = _writeRaw;
function _writeRaw(data, encoding, callback) {
  const conn = this.socket;
  if (conn && conn.destroyed) {
    // The socket was destroyed. If we're still trying to write to it,
    // then we haven't gotten the 'close' event yet.
    return false;
  }
 
  if (typeof encoding === 'function') {
    callback = encoding;
    encoding = null;
  }
 
  if (conn && conn._httpMessage === this && conn.writable) {
    // There might be pending data in the this.output buffer.
    if (this.outputData.length) {
      this._flushOutput(conn);
    }
    // Directly write to socket.
    return conn.write(data, encoding, callback);
  }
  // Buffer, as long as we're not destroyed.
  this.outputData.push({ data, encoding, callback });
  this.outputSize += data.length;
  this._onPendingData(data.length);
  return this.outputSize < HIGH_WATER_MARK;
}
 
 
OutgoingMessage.prototype._storeHeader = _storeHeader;
function _storeHeader(firstLine, headers) {
  // firstLine in the case of request is: 'GET /index.html HTTP/1.1\r\n'
  // in the case of response it is: 'HTTP/1.1 200 OK\r\n'
  const state = {
    connection: false,
    contLen: false,
    te: false,
    date: false,
    expect: false,
    trailer: false,
    header: firstLine
  };
 
  if (headers) {
    if (headers === this[kOutHeaders]) {
      for (const key in headers) {
        const entry = headers[key];
        processHeader(this, state, entry[0], entry[1], false);
      }
    } else if (ArrayIsArray(headers)) {
      if (headers.length && ArrayIsArray(headers[0])) {
        for (let i = 0; i < headers.length; i++) {
          const entry = headers[i];
          processHeader(this, state, entry[0], entry[1], true);
        }
      } else {
        if (headers.length % 2 !== 0) {
          throw new ERR_INVALID_ARG_VALUE('headers', headers);
        }
 
        for (let n = 0; n < headers.length; n += 2) {
          processHeader(this, state, headers[n + 0], headers[n + 1], true);
        }
      }
    } else {
      for (const key in headers) {
        if (ObjectPrototypeHasOwnProperty(headers, key)) {
          processHeader(this, state, key, headers[key], true);
        }
      }
    }
  }
 
  let { header } = state;
 
  // Date header
  if (this.sendDate && !state.date) {
    header += 'Date: ' + utcDate() + '\r\n';
  }
 
  // Force the connection to close when the response is a 204 No Content or
  // a 304 Not Modified and the user has set a "Transfer-Encoding: chunked"
  // header.
  //
  // RFC 2616 mandates that 204 and 304 responses MUST NOT have a body but
  // node.js used to send out a zero chunk anyway to accommodate clients
  // that don't have special handling for those responses.
  //
  // It was pointed out that this might confuse reverse proxies to the point
  // of creating security liabilities, so suppress the zero chunk and force
  // the connection to close.
  if (this.chunkedEncoding && (this.statusCode === 204 ||
                               this.statusCode === 304)) {
    debug(this.statusCode + ' response should not use chunked encoding,' +
          ' closing connection.');
    this.chunkedEncoding = false;
    this.shouldKeepAlive = false;
  }
 
  // keep-alive logic
  if (this._removedConnection) {
    this._last = true;
    this.shouldKeepAlive = false;
  } else if (!state.connection) {
    const shouldSendKeepAlive = this.shouldKeepAlive &&
        (state.contLen || this.useChunkedEncodingByDefault || this.agent);
    if (shouldSendKeepAlive && this.maxRequestsOnConnectionReached) {
      header += 'Connection: close\r\n';
    } else if (shouldSendKeepAlive) {
      header += 'Connection: keep-alive\r\n';
      if (this._keepAliveTimeout && this._defaultKeepAlive) {
        const timeoutSeconds = MathFloor(this._keepAliveTimeout / 1000);
        header += `Keep-Alive: timeout=${timeoutSeconds}\r\n`;
      }
    } else {
      this._last = true;
      header += 'Connection: close\r\n';
    }
  }
 
  if (!state.contLen && !state.te) {
    if (!this._hasBody) {
      // Make sure we don't end the 0\r\n\r\n at the end of the message.
      this.chunkedEncoding = false;
    } else if (!this.useChunkedEncodingByDefault) {
      this._last = true;
    } else if (!state.trailer &&
               !this._removedContLen &&
               typeof this._contentLength === 'number') {
      header += 'Content-Length: ' + this._contentLength + '\r\n';
    } else if (!this._removedTE) {
      header += 'Transfer-Encoding: chunked\r\n';
      this.chunkedEncoding = true;
    } else {
      // We should only be able to get here if both Content-Length and
      // Transfer-Encoding are removed by the user.
      // See: test/parallel/test-http-remove-header-stays-removed.js
      debug('Both Content-Length and Transfer-Encoding are removed');
    }
  }
 
  // Test non-chunked message does not have trailer header set,
  // message will be terminated by the first empty line after the
  // header fields, regardless of the header fields present in the
  // message, and thus cannot contain a message body or 'trailers'.
  if (this.chunkedEncoding !== true && state.trailer) {
    throw new ERR_HTTP_TRAILER_INVALID();
  }
 
  this._header = header + '\r\n';
  this._headerSent = false;
 
  // Wait until the first body chunk, or close(), is sent to flush,
  // UNLESS we're sending Expect: 100-continue.
  if (state.expect) this._send('');
}
 
function processHeader(self, state, key, value, validate) {
  if (validate)
    validateHeaderName(key);
  if (ArrayIsArray(value)) {
    if (
      (value.length < 2 || !isCookieField(key)) &&
      (!self[kUniqueHeaders] || !self[kUniqueHeaders].has(StringPrototypeToLowerCase(key)))
    ) {
      // Retain for(;;) loop for performance reasons
      // Refs: https://github.com/nodejs/node/pull/30958
      for (let i = 0; i < value.length; i++)
        storeHeader(self, state, key, value[i], validate);
      return;
    }
    value = ArrayPrototypeJoin(value, '; ');
  }
  storeHeader(self, state, key, value, validate);
}
 
function storeHeader(self, state, key, value, validate) {
  if (validate)
    validateHeaderValue(key, value);
  state.header += key + ': ' + value + '\r\n';
  matchHeader(self, state, key, value);
}
 
function matchHeader(self, state, field, value) {
  if (field.length < 4 || field.length > 17)
    return;
  field = StringPrototypeToLowerCase(field);
  switch (field) {
    case 'connection':
      state.connection = true;
      self._removedConnection = false;
      if (RegExpPrototypeTest(RE_CONN_CLOSE, value))
        self._last = true;
      else
        self.shouldKeepAlive = true;
      break;
    case 'transfer-encoding':
      state.te = true;
      self._removedTE = false;
      if (RegExpPrototypeTest(RE_TE_CHUNKED, value))
        self.chunkedEncoding = true;
      break;
    case 'content-length':
      state.contLen = true;
      self._removedContLen = false;
      break;
    case 'date':
    case 'expect':
    case 'trailer':
      state[field] = true;
      break;
    case 'keep-alive':
      self._defaultKeepAlive = false;
      break;
  }
}
 
const validateHeaderName = hideStackFrames((name) => {
  if (typeof name !== 'string' || !name || !checkIsHttpToken(name)) {
    throw new ERR_INVALID_HTTP_TOKEN('Header name', name);
  }
});
 
const validateHeaderValue = hideStackFrames((name, value) => {
  if (value === undefined) {
    throw new ERR_HTTP_INVALID_HEADER_VALUE(value, name);
  }
  if (checkInvalidHeaderChar(value)) {
    debug('Header "%s" contains invalid characters', name);
    throw new ERR_INVALID_CHAR('header content', name);
  }
});
 
function parseUniqueHeadersOption(headers) {
  if (!ArrayIsArray(headers)) {
    return null;
  }
 
  const unique = new SafeSet();
  const l = headers.length;
  for (let i = 0; i < l; i++) {
    unique.add(StringPrototypeToLowerCase(headers[i]));
  }
 
  return unique;
}
 
OutgoingMessage.prototype.setHeader = function setHeader(name, value) {
  if (this._header) {
    throw new ERR_HTTP_HEADERS_SENT('set');
  }
  validateHeaderName(name);
  validateHeaderValue(name, value);
 
  let headers = this[kOutHeaders];
  if (headers === null)
    this[kOutHeaders] = headers = ObjectCreate(null);
 
  headers[StringPrototypeToLowerCase(name)] = [name, value];
  return this;
};
 
OutgoingMessage.prototype.appendHeader = function appendHeader(name, value) {
  if (this._header) {
    throw new ERR_HTTP_HEADERS_SENT('append');
  }
  validateHeaderName(name);
  validateHeaderValue(name, value);
 
  const field = StringPrototypeToLowerCase(name);
  const headers = this[kOutHeaders];
  if (headers === null || !headers[field]) {
    return this.setHeader(name, value);
  }
 
  // Prepare the field for appending, if required
  if (!ArrayIsArray(headers[field][1])) {
    headers[field][1] = [headers[field][1]];
  }
 
  const existingValues = headers[field][1];
  if (ArrayIsArray(value)) {
    for (let i = 0, length = value.length; i < length; i++) {
      existingValues.push(value[i]);
    }
  } else {
    existingValues.push(value);
  }
 
  return this;
};
 
 
OutgoingMessage.prototype.getHeader = function getHeader(name) {
  validateString(name, 'name');
 
  const headers = this[kOutHeaders];
  if (headers === null)
    return;
 
  const entry = headers[StringPrototypeToLowerCase(name)];
  return entry && entry[1];
};
 
 
// Returns an array of the names of the current outgoing headers.
OutgoingMessage.prototype.getHeaderNames = function getHeaderNames() {
  return this[kOutHeaders] !== null ? ObjectKeys(this[kOutHeaders]) : [];
};
 
 
// Returns an array of the names of the current outgoing raw headers.
OutgoingMessage.prototype.getRawHeaderNames = function getRawHeaderNames() {
  const headersMap = this[kOutHeaders];
  if (headersMap === null) return [];
 
  const values = ObjectValues(headersMap);
  const headers = Array(values.length);
  // Retain for(;;) loop for performance reasons
  // Refs: https://github.com/nodejs/node/pull/30958
  for (let i = 0, l = values.length; i < l; i++) {
    headers[i] = values[i][0];
  }
 
  return headers;
};
 
 
// Returns a shallow copy of the current outgoing headers.
OutgoingMessage.prototype.getHeaders = function getHeaders() {
  const headers = this[kOutHeaders];
  const ret = ObjectCreate(null);
  if (headers) {
    const keys = ObjectKeys(headers);
    // Retain for(;;) loop for performance reasons
    // Refs: https://github.com/nodejs/node/pull/30958
    for (let i = 0; i < keys.length; ++i) {
      const key = keys[i];
      const val = headers[key][1];
      ret[key] = val;
    }
  }
  return ret;
};
 
 
OutgoingMessage.prototype.hasHeader = function hasHeader(name) {
  validateString(name, 'name');
  return this[kOutHeaders] !== null &&
    !!this[kOutHeaders][StringPrototypeToLowerCase(name)];
};
 
 
OutgoingMessage.prototype.removeHeader = function removeHeader(name) {
  validateString(name, 'name');
 
  if (this._header) {
    throw new ERR_HTTP_HEADERS_SENT('remove');
  }
 
  const key = StringPrototypeToLowerCase(name);
 
  switch (key) {
    case 'connection':
      this._removedConnection = true;
      break;
    case 'content-length':
      this._removedContLen = true;
      break;
    case 'transfer-encoding':
      this._removedTE = true;
      break;
    case 'date':
      this.sendDate = false;
      break;
  }
 
  if (this[kOutHeaders] !== null) {
    delete this[kOutHeaders][key];
  }
};
 
 
OutgoingMessage.prototype._implicitHeader = function _implicitHeader() {
  throw new ERR_METHOD_NOT_IMPLEMENTED('_implicitHeader()');
};
 
ObjectDefineProperty(OutgoingMessage.prototype, 'headersSent', {
  configurable: true,
  enumerable: true,
  get: function() { return !!this._header; }
});
 
ObjectDefineProperty(OutgoingMessage.prototype, 'writableEnded', {
  get: function() { return this.finished; }
});
 
ObjectDefineProperty(OutgoingMessage.prototype, 'writableNeedDrain', {
  get: function() {
    return !this.destroyed && !this.finished && this[kNeedDrain];
  }
});
 
const crlf_buf = Buffer.from('\r\n');
OutgoingMessage.prototype.write = function write(chunk, encoding, callback) {
  if (typeof encoding === 'function') {
    callback = encoding;
    encoding = null;
  }
 
  const ret = write_(this, chunk, encoding, callback, false);
  if (!ret)
    this[kNeedDrain] = true;
  return ret;
};
 
function onError(msg, err, callback) {
  const triggerAsyncId = msg.socket ? msg.socket[async_id_symbol] : undefined;
  defaultTriggerAsyncIdScope(triggerAsyncId,
                             process.nextTick,
                             emitErrorNt,
                             msg,
                             err,
                             callback);
}
 
function emitErrorNt(msg, err, callback) {
  callback(err);
  if (typeof msg.emit === 'function' && !msg._closed) {
    msg.emit('error', err);
  }
}
 
function write_(msg, chunk, encoding, callback, fromEnd) {
  if (typeof callback !== 'function')
    callback = nop;
 
  let len;
  if (chunk === null) {
    throw new ERR_STREAM_NULL_VALUES();
  } else if (typeof chunk === 'string') {
    len = Buffer.byteLength(chunk, encoding);
  } else if (isUint8Array(chunk)) {
    len = chunk.length;
  } else {
    throw new ERR_INVALID_ARG_TYPE(
      'chunk', ['string', 'Buffer', 'Uint8Array'], chunk);
  }
 
  let err;
  if (msg.finished) {
    err = new ERR_STREAM_WRITE_AFTER_END();
  } else if (msg.destroyed) {
    err = new ERR_STREAM_DESTROYED('write');
  }
 
  if (err) {
    if (!msg.destroyed) {
      onError(msg, err, callback);
    } else {
      process.nextTick(callback, err);
    }
    return false;
  }
 
  if (!msg._header) {
    if (fromEnd) {
      msg._contentLength = len;
    }
    msg._implicitHeader();
  }
 
  if (!msg._hasBody) {
    debug('This type of response MUST NOT have a body. ' +
          'Ignoring write() calls.');
    process.nextTick(callback);
    return true;
  }
 
  if (!fromEnd && msg.socket && !msg.socket.writableCorked) {
    msg.socket.cork();
    process.nextTick(connectionCorkNT, msg.socket);
  }
 
  let ret;
  if (msg.chunkedEncoding && chunk.length !== 0) {
    msg._send(NumberPrototypeToString(len, 16), 'latin1', null);
    msg._send(crlf_buf, null, null);
    msg._send(chunk, encoding, null);
    ret = msg._send(crlf_buf, null, callback);
  } else {
    ret = msg._send(chunk, encoding, callback);
  }
 
  debug('write ret = ' + ret);
  return ret;
}
 
 
function connectionCorkNT(conn) {
  conn.uncork();
}
 
OutgoingMessage.prototype.addTrailers = function addTrailers(headers) {
  this._trailer = '';
  const keys = ObjectKeys(headers);
  const isArray = ArrayIsArray(headers);
  // Retain for(;;) loop for performance reasons
  // Refs: https://github.com/nodejs/node/pull/30958
  for (let i = 0, l = keys.length; i < l; i++) {
    let field, value;
    const key = keys[i];
    if (isArray) {
      field = headers[key][0];
      value = headers[key][1];
    } else {
      field = key;
      value = headers[key];
    }
    if (typeof field !== 'string' || !field || !checkIsHttpToken(field)) {
      throw new ERR_INVALID_HTTP_TOKEN('Trailer name', field);
    }
 
    // Check if the field must be sent several times
    const isArrayValue = ArrayIsArray(value);
    if (
      isArrayValue && value.length > 1 &&
      (!this[kUniqueHeaders] || !this[kUniqueHeaders].has(StringPrototypeToLowerCase(field)))
    ) {
      for (let j = 0, l = value.length; j < l; j++) {
        if (checkInvalidHeaderChar(value[j])) {
          debug('Trailer "%s"[%d] contains invalid characters', field, j);
          throw new ERR_INVALID_CHAR('trailer content', field);
        }
        this._trailer += field + ': ' + value[j] + '\r\n';
      }
    } else {
      if (isArrayValue) {
        value = ArrayPrototypeJoin(value, '; ');
      }
 
      if (checkInvalidHeaderChar(value)) {
        debug('Trailer "%s" contains invalid characters', field);
        throw new ERR_INVALID_CHAR('trailer content', field);
      }
      this._trailer += field + ': ' + value + '\r\n';
    }
  }
};
 
function onFinish(outmsg) {
  if (outmsg && outmsg.socket && outmsg.socket._hadError) return;
  outmsg.emit('finish');
}
 
OutgoingMessage.prototype.end = function end(chunk, encoding, callback) {
  if (typeof chunk === 'function') {
    callback = chunk;
    chunk = null;
    encoding = null;
  } else if (typeof encoding === 'function') {
    callback = encoding;
    encoding = null;
  }
 
  if (chunk) {
    if (this.finished) {
      onError(this,
              new ERR_STREAM_WRITE_AFTER_END(),
              typeof callback !== 'function' ? nop : callback);
      return this;
    }
 
    if (this.socket) {
      this.socket.cork();
    }
 
    write_(this, chunk, encoding, null, true);
  } else if (this.finished) {
    if (typeof callback === 'function') {
      if (!this.writableFinished) {
        this.on('finish', callback);
      } else {
        callback(new ERR_STREAM_ALREADY_FINISHED('end'));
      }
    }
    return this;
  } else if (!this._header) {
    if (this.socket) {
      this.socket.cork();
    }
 
    this._contentLength = 0;
    this._implicitHeader();
  }
 
  if (typeof callback === 'function')
    this.once('finish', callback);
 
  const finish = onFinish.bind(undefined, this);
 
  if (this._hasBody && this.chunkedEncoding) {
    this._send('0\r\n' + this._trailer + '\r\n', 'latin1', finish);
  } else if (!this._headerSent || this.writableLength || chunk) {
    this._send('', 'latin1', finish);
  } else {
    process.nextTick(finish);
  }
 
  if (this.socket) {
    // Fully uncork connection on end().
    this.socket._writableState.corked = 1;
    this.socket.uncork();
  }
  this[kCorked] = 0;
 
  this.finished = true;
 
  // There is the first message on the outgoing queue, and we've sent
  // everything to the socket.
  debug('outgoing message end.');
  if (this.outputData.length === 0 &&
      this.socket &&
      this.socket._httpMessage === this) {
    this._finish();
  }
 
  return this;
};
 
 
OutgoingMessage.prototype._finish = function _finish() {
  assert(this.socket);
  this.emit('prefinish');
};
 
 
// This logic is probably a bit confusing. Let me explain a bit:
//
// In both HTTP servers and clients it is possible to queue up several
// outgoing messages. This is easiest to imagine in the case of a client.
// Take the following situation:
//
//    req1 = client.request('GET', '/');
//    req2 = client.request('POST', '/');
//
// When the user does
//
//   req2.write('hello world\n');
//
// it's possible that the first request has not been completely flushed to
// the socket yet. Thus the outgoing messages need to be prepared to queue
// up data internally before sending it on further to the socket's queue.
//
// This function, outgoingFlush(), is called by both the Server and Client
// to attempt to flush any pending messages out to the socket.
OutgoingMessage.prototype._flush = function _flush() {
  const socket = this.socket;
 
  if (socket && socket.writable) {
    // There might be remaining data in this.output; write it out
    const ret = this._flushOutput(socket);
 
    if (this.finished) {
      // This is a queue to the server or client to bring in the next this.
      this._finish();
    } else if (ret && this[kNeedDrain]) {
      this[kNeedDrain] = false;
      this.emit('drain');
    }
  }
};
 
OutgoingMessage.prototype._flushOutput = function _flushOutput(socket) {
  while (this[kCorked]) {
    this[kCorked]--;
    socket.cork();
  }
 
  const outputLength = this.outputData.length;
  if (outputLength <= 0)
    return undefined;
 
  const outputData = this.outputData;
  socket.cork();
  let ret;
  // Retain for(;;) loop for performance reasons
  // Refs: https://github.com/nodejs/node/pull/30958
  for (let i = 0; i < outputLength; i++) {
    const { data, encoding, callback } = outputData[i];
    ret = socket.write(data, encoding, callback);
  }
  socket.uncork();
 
  this.outputData = [];
  this._onPendingData(-this.outputSize);
  this.outputSize = 0;
 
  return ret;
};
 
 
OutgoingMessage.prototype.flushHeaders = function flushHeaders() {
  if (!this._header) {
    this._implicitHeader();
  }
 
  // Force-flush the headers.
  this._send('');
};
 
OutgoingMessage.prototype.pipe = function pipe() {
  // OutgoingMessage should be write-only. Piping from it is disabled.
  this.emit('error', new ERR_STREAM_CANNOT_PIPE());
};
 
OutgoingMessage.prototype[EE.captureRejectionSymbol] =
function(err, event) {
  this.destroy(err);
};
 
module.exports = {
  kUniqueHeaders,
  parseUniqueHeadersOption,
  validateHeaderName,
  validateHeaderValue,
  OutgoingMessage
};