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html-to-xlsx

NPM Version License Build Status

node.js html to xlsx transformation

Transformation only supports html table and several basic style properties. No images or charts are currently supported.

Usage

const util = require('util')
const fs = require('fs')
const conversionFactory = require('html-to-xlsx')
const puppeteer = require('puppeteer')
const chromeEval = require('chrome-page-eval')({ puppeteer })
const writeFileAsync = util.promisify(fs.writeFile)

const conversion = conversionFactory({
  extract: async ({ html, ...restOptions }) => {
    const tmpHtmlPath = path.join('/path/to/temp', 'input.html')

    await writeFileAsync(tmpHtmlPath, html)

    const result = await chromeEval({
      ...restOptions,
      html: tmpHtmlPath,
      scriptFn: conversionFactory.getScriptFn()
    })

    const tables = Array.isArray(result) ? result : [result]

    return tables.map((table) => ({
      name: table.name,
      getRows: async (rowCb) => {
        table.rows.forEach((row) => {
          rowCb(row)
        })
      },
      rowsCount: table.rows.length
    }))
  }
})

async function run () {
  const stream = await conversion(`<table><tr><td>cell value</td></tr></table>`)

  stream.pipe(fs.createWriteStream('/path/to/output.xlsx'))
}

run()

Supported properties

  • background-color - cell background color
  • color - cell foreground color
  • border-left-style - as well as positions will be transformed into excel cells borders
  • text-align - text horizontal align in the excel cell
  • vertical-align - vertical align in the excel cell
  • width - the excel column will get the highest width, it can be little bit inaccurate because of pixel to excel points conversion
  • height - the excel row will get the highest height
  • font-size - font size
  • colspan - numeric value that merges current column with columns to the right
  • rowspan - numeric value that merges current row with rows below.
  • overflow - the excel cell will have text wrap enabled if this is set to scroll or auto.

Constructor options

const conversionFactory = require('html-to-xlsx')
const puppeteer = require('puppeteer')
const chromeEval = require('chrome-page-eval')({ puppeteer })
const conversion = conversionFactory({ /*[constructor options here]*/})
  • extract function [required] - a function that receives some input (an html file path and a script) and should return some data after been evaluated the html passed. the input that the function receives is:
    {
      html: <file path to a html file>,
      scriptFn: <string that contains a javascript function to evaluate in the html>,
      timeout: <time in ms to wait for the function to complete, the function should use this value to abort any execution when the time has passed>,
      /*options passed to `conversion` will be propagated to the input of this function too*/
    }
  • tmpDir string - the directory path that the module is going to use to save temporary files needed during the conversion. defaults to require('os').tmpdir()
  • timeout number - time in ms to wait for the conversion to complete, when the timeout is reached the conversion is cancelled. defaults to 10000

Conversion options

const fs = require('fs')
const conversionFactory = require('html-to-xlsx')
const puppeteer = require('puppeteer')
const chromeEval = require('chrome-page-eval')({ puppeteer })
const conversion = conversionFactory({
  extract: async ({ html, ...restOptions }) => {
    const tmpHtmlPath = path.join('/path/to/temp', 'input.html')

    await writeFileAsync(tmpHtmlPath, html)

    const result = await chromeEval({
      ...restOptions,
      html: tmpHtmlPath,
      scriptFn: conversionFactory.getScriptFn()
    })

    const tables = Array.isArray(result) ? result : [result]

    return tables.map((table) => ({
      name: table.name,
      getRows: async (rowCb) => {
        table.rows.forEach((row) => {
          rowCb(row)
        })
      },
      rowsCount: table.rows.length
    }))
  }
})

async function main () {
  const stream = await conversion(/* html */, /* extract options */)
}

main()
  • html string - the html source that will be transformed to an xlsx, the html should contain a table element
  • extractOptions object - additional options to pass to the specified extract function

License

See license