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88644eaa2d
This makes it so that `stream.push(chunk)` is the only way to signal the
end of reading, removing the confusing disparity between the
callback-style _read method, and the fact that most real-world streams
do not have a 1:1 corollation between the "please give me data" event,
and the actual arrival of a chunk of data.
It is still possible, of course, to implement a `CallbackReadable` on
top of this. Simply provide a method like this as the callback:
function readCallback(er, chunk) {
if (er)
stream.emit('error', er);
else
stream.push(chunk);
}
However, *only* fs streams actually would behave in this way, so it
makes not a lot of sense to make TCP, TLS, HTTP, and all the rest have
to bend into this uncomfortable paradigm.
85 lines
2.4 KiB
JavaScript
85 lines
2.4 KiB
JavaScript
// Copyright Joyent, Inc. and other Node contributors.
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//
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// Permission is hereby granted, free of charge, to any person obtaining a
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// copy of this software and associated documentation files (the
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// "Software"), to deal in the Software without restriction, including
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// without limitation the rights to use, copy, modify, merge, publish,
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// distribute, sublicense, and/or sell copies of the Software, and to permit
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// persons to whom the Software is furnished to do so, subject to the
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// following conditions:
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//
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// The above copyright notice and this permission notice shall be included
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// in all copies or substantial portions of the Software.
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//
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
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// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
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// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
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// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
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// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
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// USE OR OTHER DEALINGS IN THE SOFTWARE.
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var common = require('../common');
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var assert = require('assert');
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var stream = require('stream');
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var str = 'asdfasdfasdfasdfasdf';
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var r = new stream.Readable({
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highWaterMark: 5,
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encoding: 'utf8'
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});
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var reads = 0;
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var eofed = false;
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var ended = false;
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r._read = function(n) {
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if (reads === 0) {
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setTimeout(function() {
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r.push(str);
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});
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reads++;
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} else if (reads === 1) {
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var ret = r.push(str);
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assert.equal(ret, false);
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reads++;
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} else {
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assert(!eofed);
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eofed = true;
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r.push(null);
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}
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};
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r.on('end', function() {
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ended = true;
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});
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// push some data in to start.
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// we've never gotten any read event at this point.
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var ret = r.push(str);
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// should be false. > hwm
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assert(!ret);
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var chunk = r.read();
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assert.equal(chunk, str);
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chunk = r.read();
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assert.equal(chunk, null);
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r.once('readable', function() {
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// this time, we'll get *all* the remaining data, because
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// it's been added synchronously, as the read WOULD take
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// us below the hwm, and so it triggered a _read() again,
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// which synchronously added more, which we then return.
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chunk = r.read();
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assert.equal(chunk, str + str);
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chunk = r.read();
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assert.equal(chunk, null);
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});
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process.on('exit', function() {
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assert(eofed);
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assert(ended);
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assert.equal(reads, 2);
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console.log('ok');
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});
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