forked from mholt/PapaParse
/
papaparse.js
executable file
·1944 lines (1643 loc) · 51.4 KB
/
papaparse.js
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
/* @license
Papa Parse
v5.4.1
https://github.com/mholt/PapaParse
License: MIT
*/
(function(root, factory)
{
/* globals define */
if (typeof define === 'function' && define.amd)
{
// AMD. Register as an anonymous module.
define([], factory);
}
else if (typeof module === 'object' && typeof exports !== 'undefined')
{
// Node. Does not work with strict CommonJS, but
// only CommonJS-like environments that support module.exports,
// like Node.
module.exports = factory();
}
else
{
// Browser globals (root is window)
root.Papa = factory();
}
// in strict mode we cannot access arguments.callee, so we need a named reference to
// stringify the factory method for the blob worker
// eslint-disable-next-line func-name
}(this, function moduleFactory()
{
'use strict';
var global = (function() {
// alternative method, similar to `Function('return this')()`
// but without using `eval` (which is disabled when
// using Content Security Policy).
if (typeof self !== 'undefined') { return self; }
if (typeof window !== 'undefined') { return window; }
if (typeof global !== 'undefined') { return global; }
// When running tests none of the above have been defined
return {};
})();
function getWorkerBlob() {
var URL = global.URL || global.webkitURL || null;
var code = moduleFactory.toString();
return Papa.BLOB_URL || (Papa.BLOB_URL = URL.createObjectURL(new Blob(["var global = (function() { if (typeof self !== 'undefined') { return self; } if (typeof window !== 'undefined') { return window; } if (typeof global !== 'undefined') { return global; } return {}; })(); global.IS_PAPA_WORKER=true; ", '(', code, ')();'], {type: 'text/javascript'})));
}
var IS_WORKER = !global.document && !!global.postMessage,
IS_PAPA_WORKER = global.IS_PAPA_WORKER || false;
var workers = {}, workerIdCounter = 0;
var Papa = {};
Papa.parse = CsvToJson;
Papa.unparse = JsonToCsv;
Papa.RECORD_SEP = String.fromCharCode(30);
Papa.UNIT_SEP = String.fromCharCode(31);
Papa.BYTE_ORDER_MARK = '\ufeff';
Papa.BAD_DELIMITERS = ['\r', '\n', '"', Papa.BYTE_ORDER_MARK];
Papa.WORKERS_SUPPORTED = !IS_WORKER && !!global.Worker;
Papa.NODE_STREAM_INPUT = 1;
// Configurable chunk sizes for local and remote files, respectively
Papa.LocalChunkSize = 1024 * 1024 * 10; // 10 MB
Papa.RemoteChunkSize = 1024 * 1024 * 5; // 5 MB
Papa.DefaultDelimiter = ','; // Used if not specified and detection fails
// Exposed for testing and development only
Papa.Parser = Parser;
Papa.ParserHandle = ParserHandle;
Papa.NetworkStreamer = NetworkStreamer;
Papa.FileStreamer = FileStreamer;
Papa.StringStreamer = StringStreamer;
Papa.ReadableStreamStreamer = ReadableStreamStreamer;
if (typeof PAPA_BROWSER_CONTEXT === 'undefined') {
Papa.DuplexStreamStreamer = DuplexStreamStreamer;
}
if (global.jQuery)
{
var $ = global.jQuery;
$.fn.parse = function(options)
{
var config = options.config || {};
var queue = [];
this.each(function(idx)
{
var supported = $(this).prop('tagName').toUpperCase() === 'INPUT'
&& $(this).attr('type').toLowerCase() === 'file'
&& global.FileReader;
if (!supported || !this.files || this.files.length === 0)
return true; // continue to next input element
for (var i = 0; i < this.files.length; i++)
{
queue.push({
file: this.files[i],
inputElem: this,
instanceConfig: $.extend({}, config)
});
}
});
parseNextFile(); // begin parsing
return this; // maintains chainability
function parseNextFile()
{
if (queue.length === 0)
{
if (isFunction(options.complete))
options.complete();
return;
}
var f = queue[0];
if (isFunction(options.before))
{
var returned = options.before(f.file, f.inputElem);
if (typeof returned === 'object')
{
if (returned.action === 'abort')
{
error('AbortError', f.file, f.inputElem, returned.reason);
return; // Aborts all queued files immediately
}
else if (returned.action === 'skip')
{
fileComplete(); // parse the next file in the queue, if any
return;
}
else if (typeof returned.config === 'object')
f.instanceConfig = $.extend(f.instanceConfig, returned.config);
}
else if (returned === 'skip')
{
fileComplete(); // parse the next file in the queue, if any
return;
}
}
// Wrap up the user's complete callback, if any, so that ours also gets executed
var userCompleteFunc = f.instanceConfig.complete;
f.instanceConfig.complete = function(results)
{
if (isFunction(userCompleteFunc))
userCompleteFunc(results, f.file, f.inputElem);
fileComplete();
};
Papa.parse(f.file, f.instanceConfig);
}
function error(name, file, elem, reason)
{
if (isFunction(options.error))
options.error({name: name}, file, elem, reason);
}
function fileComplete()
{
queue.splice(0, 1);
parseNextFile();
}
};
}
if (IS_PAPA_WORKER)
{
global.onmessage = workerThreadReceivedMessage;
}
function CsvToJson(_input, _config)
{
_config = _config || {};
var dynamicTyping = _config.dynamicTyping || false;
if (isFunction(dynamicTyping)) {
_config.dynamicTypingFunction = dynamicTyping;
// Will be filled on first row call
dynamicTyping = {};
}
_config.dynamicTyping = dynamicTyping;
_config.transform = isFunction(_config.transform) ? _config.transform : false;
if (_config.worker && Papa.WORKERS_SUPPORTED)
{
var w = newWorker();
w.userStep = _config.step;
w.userChunk = _config.chunk;
w.userComplete = _config.complete;
w.userError = _config.error;
_config.step = isFunction(_config.step);
_config.chunk = isFunction(_config.chunk);
_config.complete = isFunction(_config.complete);
_config.error = isFunction(_config.error);
delete _config.worker; // prevent infinite loop
w.postMessage({
input: _input,
config: _config,
workerId: w.id
});
return;
}
var streamer = null;
if (_input === Papa.NODE_STREAM_INPUT && typeof PAPA_BROWSER_CONTEXT === 'undefined')
{
// create a node Duplex stream for use
// with .pipe
streamer = new DuplexStreamStreamer(_config);
return streamer.getStream();
}
else if (typeof _input === 'string')
{
_input = stripBom(_input);
if (_config.download)
streamer = new NetworkStreamer(_config);
else
streamer = new StringStreamer(_config);
}
else if (_input.readable === true && isFunction(_input.read) && isFunction(_input.on))
{
streamer = new ReadableStreamStreamer(_config);
}
else if ((global.File && _input instanceof File) || _input instanceof Object) // ...Safari. (see issue #106)
streamer = new FileStreamer(_config);
return streamer.stream(_input);
// Strip character from UTF-8 BOM encoded files that cause issue parsing the file
function stripBom(string) {
if (string.charCodeAt(0) === 0xfeff) {
return string.slice(1);
}
return string;
}
}
function JsonToCsv(_input, _config)
{
// Default configuration
/** whether to surround every datum with quotes */
var _quotes = false;
/** whether to write headers */
var _writeHeader = true;
/** delimiting character(s) */
var _delimiter = ',';
/** newline character(s) */
var _newline = '\r\n';
/** quote character */
var _quoteChar = '"';
/** escaped quote character, either "" or <config.escapeChar>" */
var _escapedQuote = _quoteChar + _quoteChar;
/** whether to skip empty lines */
var _skipEmptyLines = false;
/** the columns (keys) we expect when we unparse objects */
var _columns = null;
/** whether to prevent outputting cells that can be parsed as formulae by spreadsheet software (Excel and LibreOffice) */
var _escapeFormulae = false;
unpackConfig();
var quoteCharRegex = new RegExp(escapeRegExp(_quoteChar), 'g');
if (typeof _input === 'string')
_input = JSON.parse(_input);
if (Array.isArray(_input))
{
if (!_input.length || Array.isArray(_input[0]))
return serialize(null, _input, _skipEmptyLines);
else if (typeof _input[0] === 'object')
return serialize(_columns || Object.keys(_input[0]), _input, _skipEmptyLines);
}
else if (typeof _input === 'object')
{
if (typeof _input.data === 'string')
_input.data = JSON.parse(_input.data);
if (Array.isArray(_input.data))
{
if (!_input.fields)
_input.fields = _input.meta && _input.meta.fields || _columns;
if (!_input.fields)
_input.fields = Array.isArray(_input.data[0])
? _input.fields
: typeof _input.data[0] === 'object'
? Object.keys(_input.data[0])
: [];
if (!(Array.isArray(_input.data[0])) && typeof _input.data[0] !== 'object')
_input.data = [_input.data]; // handles input like [1,2,3] or ['asdf']
}
return serialize(_input.fields || [], _input.data || [], _skipEmptyLines);
}
// Default (any valid paths should return before this)
throw new Error('Unable to serialize unrecognized input');
function unpackConfig()
{
if (typeof _config !== 'object')
return;
if (typeof _config.delimiter === 'string'
&& !Papa.BAD_DELIMITERS.filter(function(value) { return _config.delimiter.indexOf(value) !== -1; }).length)
{
_delimiter = _config.delimiter;
}
if (typeof _config.quotes === 'boolean'
|| typeof _config.quotes === 'function'
|| Array.isArray(_config.quotes))
_quotes = _config.quotes;
if (typeof _config.skipEmptyLines === 'boolean'
|| typeof _config.skipEmptyLines === 'string')
_skipEmptyLines = _config.skipEmptyLines;
if (typeof _config.newline === 'string')
_newline = _config.newline;
if (typeof _config.quoteChar === 'string')
_quoteChar = _config.quoteChar;
if (typeof _config.header === 'boolean')
_writeHeader = _config.header;
if (Array.isArray(_config.columns)) {
if (_config.columns.length === 0) throw new Error('Option columns is empty');
_columns = _config.columns;
}
if (_config.escapeChar !== undefined) {
_escapedQuote = _config.escapeChar + _quoteChar;
}
if (typeof _config.escapeFormulae === 'boolean' || _config.escapeFormulae instanceof RegExp) {
_escapeFormulae = _config.escapeFormulae instanceof RegExp ? _config.escapeFormulae : /^[=+\-@\t\r].*$/;
}
}
/** The double for loop that iterates the data and writes out a CSV string including header row */
function serialize(fields, data, skipEmptyLines)
{
var csv = '';
if (typeof fields === 'string')
fields = JSON.parse(fields);
if (typeof data === 'string')
data = JSON.parse(data);
var hasHeader = Array.isArray(fields) && fields.length > 0;
var dataKeyedByField = !(Array.isArray(data[0]));
// If there a header row, write it first
if (hasHeader && _writeHeader)
{
for (var i = 0; i < fields.length; i++)
{
if (i > 0)
csv += _delimiter;
csv += safe(fields[i], i);
}
if (data.length > 0)
csv += _newline;
}
// Then write out the data
for (var row = 0; row < data.length; row++)
{
var maxCol = hasHeader ? fields.length : data[row].length;
var emptyLine = false;
var nullLine = hasHeader ? Object.keys(data[row]).length === 0 : data[row].length === 0;
if (skipEmptyLines && !hasHeader)
{
emptyLine = skipEmptyLines === 'greedy' ? data[row].join('').trim() === '' : data[row].length === 1 && data[row][0].length === 0;
}
if (skipEmptyLines === 'greedy' && hasHeader) {
var line = [];
for (var c = 0; c < maxCol; c++) {
var cx = dataKeyedByField ? fields[c] : c;
line.push(data[row][cx]);
}
emptyLine = line.join('').trim() === '';
}
if (!emptyLine)
{
for (var col = 0; col < maxCol; col++)
{
if (col > 0 && !nullLine)
csv += _delimiter;
var colIdx = hasHeader && dataKeyedByField ? fields[col] : col;
csv += safe(data[row][colIdx], col);
}
if (row < data.length - 1 && (!skipEmptyLines || (maxCol > 0 && !nullLine)))
{
csv += _newline;
}
}
}
return csv;
}
/** Encloses a value around quotes if needed (makes a value safe for CSV insertion) */
function safe(str, col)
{
if (typeof str === 'undefined' || str === null)
return '';
if (str.constructor === Date)
return JSON.stringify(str).slice(1, 25);
var needsQuotes = false;
if (_escapeFormulae && typeof str === "string" && _escapeFormulae.test(str)) {
str = "'" + str;
needsQuotes = true;
}
var escapedQuoteStr = str.toString().replace(quoteCharRegex, _escapedQuote);
needsQuotes = needsQuotes
|| _quotes === true
|| (typeof _quotes === 'function' && _quotes(str, col))
|| (Array.isArray(_quotes) && _quotes[col])
|| hasAny(escapedQuoteStr, Papa.BAD_DELIMITERS)
|| escapedQuoteStr.indexOf(_delimiter) > -1
|| escapedQuoteStr.charAt(0) === ' '
|| escapedQuoteStr.charAt(escapedQuoteStr.length - 1) === ' ';
return needsQuotes ? _quoteChar + escapedQuoteStr + _quoteChar : escapedQuoteStr;
}
function hasAny(str, substrings)
{
for (var i = 0; i < substrings.length; i++)
if (str.indexOf(substrings[i]) > -1)
return true;
return false;
}
}
/** ChunkStreamer is the base prototype for various streamer implementations. */
function ChunkStreamer(config)
{
this._handle = null;
this._finished = false;
this._completed = false;
this._halted = false;
this._input = null;
this._baseIndex = 0;
this._partialLine = '';
this._rowCount = 0;
this._start = 0;
this._nextChunk = null;
this.isFirstChunk = true;
this._completeResults = {
data: [],
errors: [],
meta: {}
};
replaceConfig.call(this, config);
this.parseChunk = function(chunk, isFakeChunk)
{
// First chunk pre-processing
if (this.isFirstChunk && isFunction(this._config.beforeFirstChunk))
{
var modifiedChunk = this._config.beforeFirstChunk(chunk);
if (modifiedChunk !== undefined)
chunk = modifiedChunk;
}
this.isFirstChunk = false;
this._halted = false;
// Rejoin the line we likely just split in two by chunking the file
var aggregate = this._partialLine + chunk;
this._partialLine = '';
var results = this._handle.parse(aggregate, this._baseIndex, !this._finished);
if (this._handle.paused() || this._handle.aborted()) {
this._halted = true;
return;
}
var lastIndex = results.meta.cursor;
if (!this._finished)
{
this._partialLine = aggregate.substring(lastIndex - this._baseIndex);
this._baseIndex = lastIndex;
}
if (results && results.data)
this._rowCount += results.data.length;
var finishedIncludingPreview = this._finished || (this._config.preview && this._rowCount >= this._config.preview);
if (IS_PAPA_WORKER)
{
global.postMessage({
results: results,
workerId: Papa.WORKER_ID,
finished: finishedIncludingPreview
});
}
else if (isFunction(this._config.chunk) && !isFakeChunk)
{
this._config.chunk(results, this._handle);
if (this._handle.paused() || this._handle.aborted()) {
this._halted = true;
return;
}
results = undefined;
this._completeResults = undefined;
}
if (!this._config.step && !this._config.chunk) {
this._completeResults.data = this._completeResults.data.concat(results.data);
this._completeResults.errors = this._completeResults.errors.concat(results.errors);
this._completeResults.meta = results.meta;
}
if (!this._completed && finishedIncludingPreview && isFunction(this._config.complete) && (!results || !results.meta.aborted)) {
this._config.complete(this._completeResults, this._input);
this._completed = true;
}
if (!finishedIncludingPreview && (!results || !results.meta.paused))
this._nextChunk();
return results;
};
this._sendError = function(error)
{
if (isFunction(this._config.error))
this._config.error(error);
else if (IS_PAPA_WORKER && this._config.error)
{
global.postMessage({
workerId: Papa.WORKER_ID,
error: error,
finished: false
});
}
};
function replaceConfig(config)
{
// Deep-copy the config so we can edit it
var configCopy = copy(config);
configCopy.chunkSize = parseInt(configCopy.chunkSize); // parseInt VERY important so we don't concatenate strings!
if (!config.step && !config.chunk)
configCopy.chunkSize = null; // disable Range header if not streaming; bad values break IIS - see issue #196
this._handle = new ParserHandle(configCopy);
this._handle.streamer = this;
this._config = configCopy; // persist the copy to the caller
}
}
function NetworkStreamer(config)
{
config = config || {};
if (!config.chunkSize)
config.chunkSize = Papa.RemoteChunkSize;
ChunkStreamer.call(this, config);
var xhr;
if (IS_WORKER)
{
this._nextChunk = function()
{
this._readChunk();
this._chunkLoaded();
};
}
else
{
this._nextChunk = function()
{
this._readChunk();
};
}
this.stream = function(url)
{
this._input = url;
this._nextChunk(); // Starts streaming
};
this._readChunk = function()
{
if (this._finished)
{
this._chunkLoaded();
return;
}
xhr = new XMLHttpRequest();
if (this._config.withCredentials)
{
xhr.withCredentials = this._config.withCredentials;
}
if (!IS_WORKER)
{
xhr.onload = bindFunction(this._chunkLoaded, this);
xhr.onerror = bindFunction(this._chunkError, this);
}
xhr.open(this._config.downloadRequestBody ? 'POST' : 'GET', this._input, !IS_WORKER);
// Headers can only be set when once the request state is OPENED
if (this._config.downloadRequestHeaders)
{
var headers = this._config.downloadRequestHeaders;
for (var headerName in headers)
{
xhr.setRequestHeader(headerName, headers[headerName]);
}
}
if (this._config.chunkSize)
{
var end = this._start + this._config.chunkSize - 1; // minus one because byte range is inclusive
xhr.setRequestHeader('Range', 'bytes=' + this._start + '-' + end);
}
try {
xhr.send(this._config.downloadRequestBody);
}
catch (err) {
this._chunkError(err.message);
}
if (IS_WORKER && xhr.status === 0)
this._chunkError();
};
this._chunkLoaded = function()
{
if (xhr.readyState !== 4)
return;
if (xhr.status < 200 || xhr.status >= 400)
{
this._chunkError();
return;
}
// Use chunckSize as it may be a diference on reponse lentgh due to characters with more than 1 byte
this._start += this._config.chunkSize ? this._config.chunkSize : xhr.responseText.length;
this._finished = !this._config.chunkSize || this._start >= getFileSize(xhr);
this.parseChunk(xhr.responseText);
};
this._chunkError = function(errorMessage)
{
var errorText = xhr.statusText || errorMessage;
this._sendError(new Error(errorText));
};
function getFileSize(xhr)
{
var contentRange = xhr.getResponseHeader('Content-Range');
if (contentRange === null) { // no content range, then finish!
return -1;
}
return parseInt(contentRange.substring(contentRange.lastIndexOf('/') + 1));
}
}
NetworkStreamer.prototype = Object.create(ChunkStreamer.prototype);
NetworkStreamer.prototype.constructor = NetworkStreamer;
function FileStreamer(config)
{
config = config || {};
if (!config.chunkSize)
config.chunkSize = Papa.LocalChunkSize;
ChunkStreamer.call(this, config);
var reader, slice;
// FileReader is better than FileReaderSync (even in worker) - see http://stackoverflow.com/q/24708649/1048862
// But Firefox is a pill, too - see issue #76: https://github.com/mholt/PapaParse/issues/76
var usingAsyncReader = typeof FileReader !== 'undefined'; // Safari doesn't consider it a function - see issue #105
this.stream = function(file)
{
this._input = file;
slice = file.slice || file.webkitSlice || file.mozSlice;
if (usingAsyncReader)
{
reader = new FileReader(); // Preferred method of reading files, even in workers
reader.onload = bindFunction(this._chunkLoaded, this);
reader.onerror = bindFunction(this._chunkError, this);
}
else
reader = new FileReaderSync(); // Hack for running in a web worker in Firefox
this._nextChunk(); // Starts streaming
};
this._nextChunk = function()
{
if (!this._finished && (!this._config.preview || this._rowCount < this._config.preview))
this._readChunk();
};
this._readChunk = function()
{
var input = this._input;
if (this._config.chunkSize)
{
var end = Math.min(this._start + this._config.chunkSize, this._input.size);
input = slice.call(input, this._start, end);
}
var txt = reader.readAsText(input, this._config.encoding);
if (!usingAsyncReader)
this._chunkLoaded({ target: { result: txt } }); // mimic the async signature
};
this._chunkLoaded = function(event)
{
// Very important to increment start each time before handling results
this._start += this._config.chunkSize;
this._finished = !this._config.chunkSize || this._start >= this._input.size;
this.parseChunk(event.target.result);
};
this._chunkError = function()
{
this._sendError(reader.error);
};
}
FileStreamer.prototype = Object.create(ChunkStreamer.prototype);
FileStreamer.prototype.constructor = FileStreamer;
function StringStreamer(config)
{
config = config || {};
ChunkStreamer.call(this, config);
var remaining;
this.stream = function(s)
{
remaining = s;
return this._nextChunk();
};
this._nextChunk = function()
{
if (this._finished) return;
var size = this._config.chunkSize;
var chunk;
if(size) {
chunk = remaining.substring(0, size);
remaining = remaining.substring(size);
} else {
chunk = remaining;
remaining = '';
}
this._finished = !remaining;
return this.parseChunk(chunk);
};
}
StringStreamer.prototype = Object.create(StringStreamer.prototype);
StringStreamer.prototype.constructor = StringStreamer;
function ReadableStreamStreamer(config)
{
config = config || {};
ChunkStreamer.call(this, config);
var queue = [];
var parseOnData = true;
var streamHasEnded = false;
this.pause = function()
{
ChunkStreamer.prototype.pause.apply(this, arguments);
this._input.pause();
};
this.resume = function()
{
ChunkStreamer.prototype.resume.apply(this, arguments);
this._input.resume();
};
this.stream = function(stream)
{
this._input = stream;
this._input.on('data', this._streamData);
this._input.on('end', this._streamEnd);
this._input.on('error', this._streamError);
};
this._checkIsFinished = function()
{
if (streamHasEnded && queue.length === 1) {
this._finished = true;
}
};
this._nextChunk = function()
{
this._checkIsFinished();
if (queue.length)
{
this.parseChunk(queue.shift());
}
else
{
parseOnData = true;
}
};
this._streamData = bindFunction(function(chunk)
{
try
{
queue.push(typeof chunk === 'string' ? chunk : chunk.toString(this._config.encoding));
if (parseOnData)
{
parseOnData = false;
this._checkIsFinished();
this.parseChunk(queue.shift());
}
}
catch (error)
{
this._streamError(error);
}
}, this);
this._streamError = bindFunction(function(error)
{
this._streamCleanUp();
this._sendError(error);
}, this);
this._streamEnd = bindFunction(function()
{
this._streamCleanUp();
streamHasEnded = true;
this._streamData('');
}, this);
this._streamCleanUp = bindFunction(function()
{
this._input.removeListener('data', this._streamData);
this._input.removeListener('end', this._streamEnd);
this._input.removeListener('error', this._streamError);
}, this);
}
ReadableStreamStreamer.prototype = Object.create(ChunkStreamer.prototype);
ReadableStreamStreamer.prototype.constructor = ReadableStreamStreamer;
function DuplexStreamStreamer(_config) {
var Duplex = require('stream').Duplex;
var config = copy(_config);
var parseOnWrite = true;
var writeStreamHasFinished = false;
var parseCallbackQueue = [];
var stream = null;
this._onCsvData = function(results)
{
var data = results.data;
if (!stream.push(data) && !this._handle.paused()) {
// the writeable consumer buffer has filled up
// so we need to pause until more items
// can be processed
this._handle.pause();
}
};
this._onCsvComplete = function()
{
// node will finish the read stream when
// null is pushed
stream.push(null);
};
config.step = bindFunction(this._onCsvData, this);
config.complete = bindFunction(this._onCsvComplete, this);
ChunkStreamer.call(this, config);
this._nextChunk = function()
{
if (writeStreamHasFinished && parseCallbackQueue.length === 1) {
this._finished = true;
}
if (parseCallbackQueue.length) {
parseCallbackQueue.shift()();
} else {
parseOnWrite = true;
}
};
this._addToParseQueue = function(chunk, callback)
{
// add to queue so that we can indicate
// completion via callback
// node will automatically pause the incoming stream
// when too many items have been added without their
// callback being invoked
parseCallbackQueue.push(bindFunction(function() {
this.parseChunk(typeof chunk === 'string' ? chunk : chunk.toString(config.encoding));
if (isFunction(callback)) {
return callback();
}
}, this));
if (parseOnWrite) {
parseOnWrite = false;
this._nextChunk();
}
};
this._onRead = function()
{
if (this._handle.paused()) {
// the writeable consumer can handle more data
// so resume the chunk parsing
this._handle.resume();
}
};
this._onWrite = function(chunk, encoding, callback)
{
this._addToParseQueue(chunk, callback);
};
this._onWriteComplete = function()
{
writeStreamHasFinished = true;
// have to write empty string
// so parser knows its done
this._addToParseQueue('');
};
this.getStream = function()