CSV

Works with CSV data. I haven't tested with xlsx or other similar data types yet.

Usage

Both csv.parse() and csv.stringify() accepts the data to be parsed/stringified as the first argument, and an option's object as the second.

Parse

Parses CSV string to JS data, automatically uses first line as headers. Pass data as first argument.

const assert = require('assert')
const { csv } = require('parserblade')
const input = 'title,platform\nStardew Valley,Steam'
const result = csv.parse(input)

assert.deepStrictEqual(
  result,
  [ { title: 'Stardew Valley', platform: 'Steam' } ]
)

Parse headers

Don't use first line as headers. Pass { headers: false } as second parameter.

const assert = require('assert')
const { csv } = require('parserblade')
const input = 'name,email\nNetflix,contact@netflix.com'
const result = csv.parse(input, { headers: false })

assert.deepStrictEqual(
  result,
  [
    ['name', 'email'],
    ['Netflix', 'contact@netflix.com']
  ]
)

Specify headers passing { headers: ['name', 'email'] }

const assert = require('assert')
const { csv } = require('parserblade')
const input = 'name,email\nNetflix,contact@netflix.com'
const result = csv.parse(input, { headers: false })

assert.deepStrictEqual(
  result,
  [
    { name: 'Netflix', email: 'contact@netflix.com' }
  ]
)

Specify a function to transform headers passing { headers: header => header.toUpperCase() }

const assert = require('assert')
const { csv } = require('parserblade')
const input = 'name,email\nNetflix,contact@netflix.com'
const result = csv.parse(input, { headers: false })

assert.deepStrictEqual(
  result,
  [
    { NAME: 'Netflix', EMAIL: 'contact@netflix.com' }
  ]
)

Parse with custom delimiters

Uses custom delimiters. Anything you want! Pass { delimiter: ';' } as option.

const assert = require('assert')
const { csv } = require('parserblade')
const input = 'name;email\nNetflix;contact@netflix.com'
const result = csv.parse(input, { delimiter: ';' })

assert.deepStrictEqual(
  result,
  [ { name: 'Netflix', email: 'contact@netflix.com' } ]
)

Parse skipping some lines

Pass { skipLines: 2 } as option.

const assert = require('assert')
const { csv } = require('parserblade')
const input = 'coll streaming platforms\nname,email\nNetflix,contact@netflix.com'
const result = csv.parse(input, { skipLines: 2 })

assert.deepStrictEqual(
  result,
  [ { name: 'Netflix', email: 'contact@netflix.com' } ]
)

Parse offset

Pass { offset: 2 } as option.

const assert = require('assert')
const { csv } = require('parserblade')
const input = 'name,email\nNetflix,contact@netflix.com\nAmazon,contact@amazon.com'
const result = csv.parse(input, { offset: 2 })

assert.deepStrictEqual(
  result,
  [ { name: 'Netflix', email: 'contact@netflix.com' } ]
)

Stringify

Simply transforms JS array of objects into CSV

const assert = require('assert')
const { csv } = require('parserblade')
const input = [
  { name: 'Netflix', email: 'contact@netflix.com' }
]
const result = csv.stringify(input)

assert.equal(
  result,
  'name,email\nNetflix,contact@netflix.com'
)

Stringify omitting headers

Pass { headers: false } as options

const assert = require('assert')
const { csv } = require('parserblade')
const input = [
  { name: 'Netflix', email: 'contact@netflix.com' }
]
const result = csv.stringify(input)

assert.equal(
  result,
  'Netflix,contact@netflix.com'
)

Stringify with custom column names/headers

Specifying custom columns is easy in many forms, like just pass { columns: [ { key: '', header: '' } ] } as options.

Or { columns: ['name', 'email'] }.

Or { columns: { name: 'Name', email: 'Email' } }.

const assert = require('assert')
const { csv } = require('parserblade')
const input = [
  { name: 'Netflix', email: 'contact@netflix.com' }
]

const columns = [
  { key: 'name', header: 'Platform' },
  { key: 'email', header: 'e-mail' }
]

const result = csv.stringify(input, { columns })

assert.equal(
  result,
  'Platform,e-mail\nNetflix,contact@netflix.com'
)

Valid

Just checks if given string is a valid CSV

const assert = require('assert')
const { csv } = require('parserblade')
const result = csv.valid('name\nstardew,pokemon')

assert.equal(
  result,
  false
)

Stream

pipeStringify

Turns JS data into CSV

const { csv } = require('parserblade')
const { Readable } = require('stream')
const fs = require('fs')

const input = [{ game: 'Killing Floor' }, { game: 'Stardew Valley' }]
const reader = new Readable({
  objectMode: true,
  read (size) {
    const next = input.shift()
    this.push(next || null)
  }
})

const writer = csv.pipeStringify()
const toFile = fs.createWriteStream('./data-test.csv')

reader
  .pipe(writer)
  .pipe(toFile)
  .on('error', console.log)
  .on('end', () => {
    console.log('done')
  })

pipeStringify with custom delimiter

const { csv } = require('parserblade')
const { Readable } = require('stream')
const fs = require('fs')

const input = [{ game: 'Killing Floor' }, { game: 'Stardew Valley' }]
const reader = new Readable({
  objectMode: true,
  read (size) {
    const next = input.shift()
    this.push(next || null)
  }
})

const writer = csv.pipeStringify({ delimiter: ';' })
const toFile = fs.createWriteStream('./data-test.csv')

reader
  .pipe(writer)
  .pipe(toFile)
  .on('error', console.log)
  .on('end', () => {
    console.log('done')
  })

pipeStringify with custom column names

const { csv } = require('parserblade')
const { Readable } = require('stream')
const fs = require('fs')

const input = [{ game: 'Killing Floor' }, { game: 'Stardew Valley' }]
const reader = new Readable({
  objectMode: true,
  read (size) {
    const next = input.shift()
    this.push(next || null)
  }
})

const columns = [
  { key: 'game', header: 'title' }
]

const writer = csv.pipeStringify({ columns })
const toFile = fs.createWriteStream('./data-test.csv')

reader
  .pipe(writer)
  .pipe(toFile)
  .on('error', console.log)
  .on('end', () => {
    console.log('done')
  })

pipeStringify reordering columns

const { csv } = require('parserblade')
const { Readable } = require('stream')
const fs = require('fs')

const input = [{ game: 'Killing Floor', platform: 'Windows 10' }, { game: 'Stardew Valley', platform: 'Windows 10' }]
const reader = new Readable({
  objectMode: true,
  read (size) {
    const next = input.shift()
    this.push(next || null)
  }
})

const columns = [
  { key: 'platform' },
  { key: 'game' }
]

const writer = csv.pipeStringify({ columns })
const toFile = fs.createWriteStream('./data-test.csv')

reader
  .pipe(writer)
  .pipe(toFile)
  .on('error', console.log)
  .on('end', () => {
    console.log('done')
  })

pipeParse

const { csv } = require('parserblade')
const fs = require('fs')
const path = require('path')
const filepath = path.resolve(__dirname, '../data/services.csv')

const reader = fs.createReadStream(filepath)
const writer = csv.pipeParse()

reader
  .pipe(writer)
  .on('readable', console.log)
  .on('error', console.log)
  .on('end', () => {
    console.log('done')
  })

pipeParse setting custom delimiter

const { csv } = require('parserblade')
const fs = require('fs')
const path = require('path')
const filepath = path.resolve(__dirname, '../data/services.csv')

const reader = fs.createReadStream(filepath)
const writer = csv.pipeParse({ delimiter: ';' })

reader
  .pipe(writer)
  .on('readable', console.log)
  .on('error', console.log)
  .on('end', () => {
    console.log('done')
  })

pipeParse without using first line as header

const { csv } = require('parserblade')
const fs = require('fs')
const path = require('path')
const filepath = path.resolve(__dirname, '../data/services.csv')

const reader = fs.createReadStream(filepath)
const writer = csv.pipeParse({ headers: false })

reader
  .pipe(writer)
  .on('readable', console.log)
  .on('error', console.log)
  .on('end', () => {
    console.log('done')
  })