@alesmenzel/csv

Simple and elegant streaming csv parser.

Handles formats defined by RFC4180 but also works with format produced by PHP's fputcsv. Note in mind, that there is no defacto standard for CSV and different csv libraries create slightly different versions, for example some of them

• use comments in csv # this is a comment (see relaxComments and comment options)
• use escaping character instead of double quoting "\"" (this is valid csv cell in PHP's version, handled by default)
• use blank spaces after quoted fields "abc" ,"cde" (see relaxCharactersAfterQuotedText option)
• output different column count per each row (see relaxColumnCount option)
• Byte Order Mark (BOM) at the start of CSV (see bom option)
• do not contain the row delimiter (e.g. newline) on the last row (handled by default)

By default we are very strict about parsing the CSV, but can use the relax* rules to lower the bar.

Installation

npm i --save @alesmenzel/csv

Usage

const createCSVParser = require('@alesmenzel/csv')

const csv = new createCSVParser({
  // delimiter: ',' (default)
  // quote: '"' (default)
  // rowDelimiter: '\n' (default) - handles \r\n as well
  // escape: '\\' (default)
  // ... and other (see options below)
  // ... you can pass Transform stream options here - e.g. highWaterMark
})

const rows = []
csv.on('data', (row) => {
  rows.push(row)
})

csv.on('end', () => {
  console.log(rows)
})

csv.write('A,B,C\n')
csv.write('a,b,c\n')
csv.end('x,"Joe ""The Death"" Black",z\n')

Options

| Option | Description | Default Value | | -------------------------------------------------- | --------------------------------------------------------------------------------------------- | -------------------------------- | | delimiter | Single character that is used to delimit the cells in a row. | , | | rowDelimiter | Single character that is used to delimit the rows in the input. | \n (optionally preceded by \r) | | quote | Single character that is used to quote the value of a cell. | " | | escape | Single character that is used to escape a character inside the cell. | \ | | comment | Single character that is used to define a comment line. | # | | bom | Strip BOM from the first line of CSV if present. | true | | relaxComments | Allow comments in CSV. Comments are lines that start with the comment character. | false | | relaxCharactersAfterQuotedText | Allow extranious characters after end of quoted cell, but those extra characters are ignored. | false | | relaxComments | Allow comments in CSV. Comments are lines that start with the comment character. | false | | relaxColumnCount | Allow inconsistent column count per each row. | false | | highWaterMark and other transform stream options | Other options are passed to the underlaying Transform stream. | - |

Events

Besides the standard stream events, we emit the following:

Event "comment" (comment: string)

When a comment line is found. The payload is the actual comment string without the comment character (e.g. #).

csv.on('comment', (comment: string) => {
  // ...
})

Licence

This package is developed under the MIT licence.