All files / lib/internal/streams end-of-stream.js

99.57% Statements 232/233
95.87% Branches 116/121
93.75% Functions 15/16
99.57% Lines 232/233

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 23420x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 20x 242x 242x 242x 20x 242x 242x 242x 242x 242x 242x 7x 242x 242x 20x 257x 257x 257x 257x 257x 20x 221x 221x 221x 221x 221x 20x 50x 50x 50x 50x 50x 50x 20x 20x 20x 66x 66x 66x 66x 66x 66x 20x 245x 245x 91x 91x 245x 4x 154x 150x 150x 244x 244x 244x 244x 244x 245x 245x 245x 245x 245x 245x 245x 245x 245x 245x 8x 245x 245x 245x 245x 245x 245x 235x 235x 235x 235x 235x 121x 245x 245x 245x 245x 245x 62x 62x 62x 62x 62x 62x 62x 62x 245x 245x 245x 245x 245x 49x 49x 49x 49x 49x 49x 49x 49x 245x 245x 245x 88x 245x 245x 245x 180x 66x 66x 65x 66x 180x 50x 50x 50x 50x 65x 245x 245x 245x   245x 245x 245x 8x 8x 8x 8x 8x 8x 245x 11x 11x 11x 242x 242x 245x 5x 5x 242x 242x 242x 242x 242x 242x 242x 245x 240x 240x 240x 240x 240x 209x 209x 82x 209x 245x 245x 245x 37x 37x 37x 37x 37x 37x 37x 37x 37x 37x 242x 242x 24x 24x 24x 24x 24x 24x 24x 24x 24x 24x 24x 24x 242x 242x 245x 6x 5x 5x 5x 5x 6x 6x 2x 6x 4x 4x 4x 4x 4x 4x 4x 6x 242x 242x 245x 20x 20x  
// Ported from https://github.com/mafintosh/end-of-stream with
// permission from the author, Mathias Buus (@mafintosh).
 
'use strict';
 
const {
  AbortError,
  codes,
} = require('internal/errors');
const {
  ERR_STREAM_PREMATURE_CLOSE
} = codes;
const { once } = require('internal/util');
const {
  validateAbortSignal,
  validateFunction,
  validateObject,
} = require('internal/validators');
 
function isRequest(stream) {
  return stream.setHeader && typeof stream.abort === 'function';
}
 
function isServerResponse(stream) {
  return (
    typeof stream._sent100 === 'boolean' &&
    typeof stream._removedConnection === 'boolean' &&
    typeof stream._removedContLen === 'boolean' &&
    typeof stream._removedTE === 'boolean' &&
    typeof stream._closed === 'boolean'
  );
}
 
function isReadable(stream) {
  return typeof stream.readable === 'boolean' ||
    typeof stream.readableEnded === 'boolean' ||
    !!stream._readableState;
}
 
function isWritable(stream) {
  return typeof stream.writable === 'boolean' ||
    typeof stream.writableEnded === 'boolean' ||
    !!stream._writableState;
}
 
function isWritableFinished(stream) {
  if (stream.writableFinished) return true;
  const wState = stream._writableState;
  if (!wState || wState.errored) return false;
  return wState.finished || (wState.ended && wState.length === 0);
}
 
const nop = () => {};
 
function isReadableEnded(stream) {
  if (stream.readableEnded) return true;
  const rState = stream._readableState;
  if (!rState || rState.errored) return false;
  return rState.endEmitted || (rState.ended && rState.length === 0);
}
 
function eos(stream, options, callback) {
  if (arguments.length === 2) {
    callback = options;
    options = {};
  } else if (options == null) {
    options = {};
  } else {
    validateObject(options, 'options');
  }
  validateFunction(callback, 'callback');
  validateAbortSignal(options.signal, 'options.signal');
 
  callback = once(callback);
 
  const readable = options.readable ||
    (options.readable !== false && isReadable(stream));
  const writable = options.writable ||
    (options.writable !== false && isWritable(stream));
 
  const wState = stream._writableState;
  const rState = stream._readableState;
  const state = wState || rState;
 
  const onlegacyfinish = () => {
    if (!stream.writable) onfinish();
  };
 
  // TODO (ronag): Improve soft detection to include core modules and
  // common ecosystem modules that do properly emit 'close' but fail
  // this generic check.
  let willEmitClose = isServerResponse(stream) || (
    state &&
    state.autoDestroy &&
    state.emitClose &&
    state.closed === false &&
    isReadable(stream) === readable &&
    isWritable(stream) === writable
  );
 
  let writableFinished = stream.writableFinished ||
    (wState && wState.finished);
  const onfinish = () => {
    writableFinished = true;
    // Stream should not be destroyed here. If it is that
    // means that user space is doing something differently and
    // we cannot trust willEmitClose.
    if (stream.destroyed) willEmitClose = false;
 
    if (willEmitClose && (!stream.readable || readable)) return;
    if (!readable || readableEnded) callback.call(stream);
  };
 
  let readableEnded = stream.readableEnded ||
    (rState && rState.endEmitted);
  const onend = () => {
    readableEnded = true;
    // Stream should not be destroyed here. If it is that
    // means that user space is doing something differently and
    // we cannot trust willEmitClose.
    if (stream.destroyed) willEmitClose = false;
 
    if (willEmitClose && (!stream.writable || writable)) return;
    if (!writable || writableFinished) callback.call(stream);
  };
 
  const onerror = (err) => {
    callback.call(stream, err);
  };
 
  const onclose = () => {
    if (readable && !readableEnded) {
      if (!isReadableEnded(stream))
        return callback.call(stream,
                             new ERR_STREAM_PREMATURE_CLOSE());
    }
    if (writable && !writableFinished) {
      if (!isWritableFinished(stream))
        return callback.call(stream,
                             new ERR_STREAM_PREMATURE_CLOSE());
    }
    callback.call(stream);
  };
 
  const onrequest = () => {
    stream.req.on('finish', onfinish);
  };
 
  if (isRequest(stream)) {
    stream.on('complete', onfinish);
    if (!willEmitClose) {
      stream.on('abort', onclose);
    }
    if (stream.req) onrequest();
    else stream.on('request', onrequest);
  } else if (writable && !wState) { // legacy streams
    stream.on('end', onlegacyfinish);
    stream.on('close', onlegacyfinish);
  }
 
  // Not all streams will emit 'close' after 'aborted'.
  if (!willEmitClose && typeof stream.aborted === 'boolean') {
    stream.on('aborted', onclose);
  }
 
  stream.on('end', onend);
  stream.on('finish', onfinish);
  if (options.error !== false) stream.on('error', onerror);
  stream.on('close', onclose);
 
  // _closed is for OutgoingMessage which is not a proper Writable.
  const closed = (!wState && !rState && stream._closed === true) || (
    (wState && wState.closed) ||
    (rState && rState.closed) ||
    (wState && wState.errorEmitted) ||
    (rState && rState.errorEmitted) ||
    (rState && stream.req && stream.aborted) ||
    (
      (!writable || (wState && wState.finished)) &&
      (!readable || (rState && rState.endEmitted))
    )
  );
 
  if (closed) {
    // TODO(ronag): Re-throw error if errorEmitted?
    // TODO(ronag): Throw premature close as if finished was called?
    // before being closed? i.e. if closed but not errored, ended or finished.
    // TODO(ronag): Throw some kind of error? Does it make sense
    // to call finished() on a "finished" stream?
    // TODO(ronag): willEmitClose?
    process.nextTick(() => {
      callback();
    });
  }
 
  const cleanup = () => {
    callback = nop;
    stream.removeListener('aborted', onclose);
    stream.removeListener('complete', onfinish);
    stream.removeListener('abort', onclose);
    stream.removeListener('request', onrequest);
    if (stream.req) stream.req.removeListener('finish', onfinish);
    stream.removeListener('end', onlegacyfinish);
    stream.removeListener('close', onlegacyfinish);
    stream.removeListener('finish', onfinish);
    stream.removeListener('end', onend);
    stream.removeListener('error', onerror);
    stream.removeListener('close', onclose);
  };
 
  if (options.signal && !closed) {
    const abort = () => {
      // Keep it because cleanup removes it.
      const endCallback = callback;
      cleanup();
      endCallback.call(stream, new AbortError());
    };
    if (options.signal.aborted) {
      process.nextTick(abort);
    } else {
      const originalCallback = callback;
      callback = once((...args) => {
        options.signal.removeEventListener('abort', abort);
        originalCallback.apply(stream, args);
      });
      options.signal.addEventListener('abort', abort);
    }
  }
 
  return cleanup;
}
 
module.exports = eos;