Introduction

We already know that converting spreadsheet, excel files into the CSV format is very easy.
This library will help NodeJS developers to manage the CSV files.

Properties

Property	Description	Type	Default
filePath	realtive or absolute CSV file path	string	' '
encoding	character encoding (read more)	string	utf8
mode	file mode (read more)	number	0o664
fields	active CSV fields	string[]	['name', 'url', 'path']
fieldDelimiter	field delimiter	string	,
rowDelimiter	row delimiter	string	\n

Instance

        const csvOpts = {
          filePath: output_file,
          encoding: 'utf8',
          mode: 0o644,

          fields: ['name', 'url', 'picture'],
          fieldDelimiter: ',',
          rowDelimiter: '\n'
        };
        const csv = new CSV(csvOpts);

        await csv.createFile();
        await csv.addHeader();
        

Methods

createFile()

Create CSV file if it does not exist.
If the file that is requested to be created is in directories that do not exist, these directories are created.
If the file already exists, it is NOT MODIFIED.

csv.createFile();

addHeader()

Add fields into the CSV Header. Fields are defined with csvOpts.fields property.
CAUTION: Old content is deleted so only headers will exist in the CSV file after this method is used.

csv.addHeader();

writeRows(rows)

Write multiple CSV rows. Old content will be overwritten when this method is used.

csv.writeRows();

appendRows(rows)

Append multiple CSV rows. New content will be added to the old content.

csv.appendRows(rows);

readRows()

Read CSV rows and convert it into the array of objects.

csv.readRows();

Practical Examples

1. prepare CSV instance

module.exports = async (x, lib) => {
  const output_file = lib.input.output_file;
  const CSV = lib.CSV;
  const echo = lib.echo;

  const csvOpts = {
    filePath: output_file,
    encoding: 'utf8',
    mode: 0o644,

    fields: [
      'name', 'url', 'picture', 'connections',
      'activity_period_days',
      'articles_in_period', 'article_recent_title', 'article_recent_date',
      'posts_in_period', 'post_recent_txt', 'post_recent_date'],
    fieldDelimiter: ',',
    rowDelimiter: '\n'
  };
  const csv = new CSV(csvOpts);

  await csv.createFile();
  await csv.addHeader();

  echo.log('Output CSV file created and header is added.');

  lib.csv = csv;

  return x;

};

2. add new row into the CSV

module.exports = async (x, lib) => {
  const echo = lib.echo;
  const csv = lib.csv;

  echo.log(`Saving data ...`);

  await csv.appendRows([x.currentDataObject]);

  echo.log('Saved data.');


  return x;
};