csv-express

Adds a CSV response method to expressjs applications.

Usage no npm install needed!

<script type="module">
  import csvExpress from 'https://cdn.skypack.dev/csv-express';
</script>

README

csv-express

A CSV response module for Express. This is an up-to-date fork of express-csv that merges outstanding pull requests.

Changes from express-csv

  • Adds support for adding a header row to the CSV (#16)
  • Better escaping of numbers so that applications such as Excel properly recognize data types
  • Actively maintained for use Express 3 and 4
  • Up to date dependencies and tests
  • Support for different encodings ( thanks alexcrack! )

Installation

npm install csv-express

API

Methods

res.csv(data [, csvHeaders] [, responseHeaders] [, statusCode])

  • data (required): an array of arrays or objects
  • csvHeaders (optional): a Boolean for returning headers on the output CSV file. Default is false.
  • responseHeaders (optional): object containing custom HTTP response headers
  • statusCode (optional): a custom HTTP response status code. Default is 200.

Settings

#separator

The delimiter to use, default is ','.

#preventCast

Prevent Excels type casting, default is false.

#ignoreNullOrUndefined

Treat null and undefined values as empty strings in the output, default is true.

Usage

Example:

var express = require('express')
var csv = require('csv-express')
var app = express()

// Basic
app.get('/', function(req, res) {
  res.csv([
    ["a", "b", "c"]
  , ["d", "e", "f"]
  ])
})

// Add headers
app.get('/headers', function(req, res) {
  res.csv([
    {"a": 1, "b": 2, "c": 3},
    {"a": 4, "b": 5, "c": 6}
  ], true)
})

// Add response headers and status code (will throw a 500 error code)
app.get('/all-params', function(req, res) {
  res.csv([
    {"a": 1, "b": 2, "c": 3},
    {"a": 4, "b": 5, "c": 6}
  ], true, {
    "Access-Control-Allow-Origin": "*"
  }, 500)
})

app.listen(3000)

You can also pass an array of objects and optionally return a header row. Useful when working with the results from database queries using node-mysql or node-postgres.

  res.csv([
      {"name": "Sam", "age": 1},
      {"name": "Mary": "age": 2}
  ], true)

  => name, age
     Sam, 1
     Mary, 2

License

The original license is as follows:

The MIT License

Copyright (c) 2012 Seiya Konno <nulltask@gmail.com>

Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
'Software'), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:

The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

All modifications from the original are CC0.

Support

Development supported by NSF CAREER EAR-1150082 and NSF ICER-1440312