README.md

@iwsio/json-csv-core

Simple CSV export module that can export an array of JSON objects to CSV. This core library will focus on the buffered, single object conversion to CSV and is built for node and browser. You can read more about it and see a live example on my blog.

Getting Started

Install

npm i @iwsio/json-csv-core

Import with named or default exports.

import { toCsv } from '@iwsio/json-csv-core'
import toCsv from '@iwsio/json-csv-core'

In Typescript, toCsv is defined as:

declare toCsv = (data: any[], options: ExporterOptions) => string;

Example

import { toCsv } from '@iwsio/json-csv-core'

const data = [
  {
    field1: 'test',
    field2: 123,
    thing: {
      field3: true,
      field4: 'test'
    }
  },
  {field1: 'test', field2: 123, thing: { field3: true, field4: 'test'}},
  {field1: 'test', field2: 123, thing: { field3: false, field4: 'test'}},
  {field1: 'test', field2: 123, thing: { field3: true, field4: 'test'}}
]

const options = {
  fields: [
    {name: 'field1'}, // regular field by name
    {name: 'field2'},
    
    // using dot notation, we can specify which value to use.
    // provide a transform if you want the value to be modified for output.
    {name: 'thing.field3', label: 'field3', transform: (v) => v ? 'yes' : 'no'},
    {name: 'thing.field4', label: 'field4'},
  ]
}
const csv = toCsv(data, options)

field1,field2,field3,field4
test,123,yes,test
test,123,yes,test
test,123,no,test
test,123,yes,test

Options

{
  //field definitions for CSV export
  fields: [
    {
      // required: field name for source value
      name: 'string',

      // optional: column label for CSV header
      label: 'string',

      // optional: transform value before exporting
      transform: function(value) { return value; }
    }
  ],

  // Other default options:
  fieldSeparator: ',',
  ignoreHeader: false
}