csv-string

PARSE and STRINGIFY for CSV strings. It's like JSON object but for CSV. It can also work row by row. And, if can parse strings, it can be use to parse files or streams too.

Javascript CSV Strings

Parse and Stringify for CSV strings.

  • API similar to the JSON parser (CSV.parse and CSV.stringify).
  • Can also work row by row.
  • Can also be used to parse strings from readable streams (e.g. file streams).

Installation

With npm:

$ npm install csv-string

Tests

Use mocha to run the tests.

$ npm install mocha
$ mocha test

API Documentation

Converts a CSV string input to array output.

    var CSV = require('csv-string'),
     arr = CSV.parse('a,b,c\na,b,c');
 
    console.log(arr);

Output:

[ [ 'a', 'b', 'c' ], [ 'a', 'b', 'c' ] ]

If separator parameter is not provided, it is automatically detected.

Converts object input to a CSV string.

    var CSV = require('csv-string');
 
    console.log(CSV.stringify(['a', 'b', 'c']));
    console.log(CSV.stringify([['c', 'd', 'e'], ['c','d','e']]));
    console.log(CSV.stringify({a:'e', b:'f', c:'g'}));

Output:

a,b,c

c,d,e
c,d,e

e,f,g

Detects the best separator.

    var CSV = require('csv-string');
 
    console.log(CSV.detect('a,b,c'));
    console.log(CSV.detect('a;b;c'));
    console.log(CSV.detect('a|b|c'));
    console.log(CSV.detect('a\tb\tc'));

Output:

,
;
|
\t

callback(row : Array, index : Number) : undefined

Calls callback for each CSV row/line. The Array passed to callback contains the fields of the current row.

    var CSV = require('csv-string');
    var data = 'a,b,c\nd,e,f';
    CSV.forEach(data, ',', function(rowindex) {
        console.log('#' + index + ' : ', row);
    });

Output:

#0 :  [ 'a', 'b', 'c' ]
#1 :  [ 'd', 'e', 'f' ]

callback(row : Array) : undefined

Calls callback when a CSV row is read. The Array passed to callback contains the fields of the row.
Returns the first offset after the row.

    var CSV = require('csv-string');
    var data = 'a,b,c\nd,e,f';
    var index = CSV.read(data, ',', function(row) {
        console.log(row);
    });
    console.log(data.slice(index));

Output:

[ 'a', 'b', 'c' ]
d,e,f

callback(rows : Array) : undefined

Calls callback when all CSV rows are read. The Array passed to callback contains the rows of the file.
Returns the offset of the end of parsing (generaly it's the end of the input string).

    var CSV = require('csv-string');
    var data = 'a,b,c\nd,e,f';
    index = CSV.readAll(data, function(row) {
        console.log(row);
    });
    console.log('-' + data.slice(index) + '-');

Output:

[ [ 'a', 'b', 'c' ], [ 'd', 'e', 'f' ] ]
--

callback(rows : Array) : undefined

Calls callback when all CSV rows are read. The last row could be ignored, because the remainder could be in another chunk. The Array passed to callback contains the rows of the file. Returns the offset of the end of parsing. If the last row is ignored, the offset will point to the beginnning of the row.

    var CSV = require('csv-string');
    var data = 'a,b,c\nd,e';
    index = CSV.readChunk(data, function(row) {
        console.log(row);
    });
    console.log('-' + data.slice(index) + '-');

Output:

[ [ 'a', 'b', 'c' ] ]
--

Create a writable stream for CSV chunk. Options are :

  • separator : To indicate the CSV separator. By default is auto (see the detect function)

Example : Read CSV file from the standard input.

    var stream = CSV.createStream();
 
    stream.on('data', function (row) {
         console.log(row);
      }
    )
 
    process.stdin.resume();
    process.stdin.setEncoding('utf8');
    process.stdin.pipe(stream);

Related projects

  • https://npmjs.org/browse/keyword/csv
  • http://www.uselesscode.org/javascript/csv/
  • https://github.com/archan937/csonv.js

Benchmark

I made a very basic benchmark to compare this project to other related projects, using file streams as input. See ./bench for source code.

 
    time node ./SCRITPNAME.js >/dev/null
 
Package Input equal Output Time for ~1 200 000 rows
a-csv almost 0m13.903s
csv-streamer yes 0m15.599s
csv-stream yes 0m17.265s
csv-string yes 0m15.432s
fast-csv no -
nodecsv yes 0m22.129s

License

MIT/X11