xlsx-extract

extracts data from XLSX files with low memory footprint

xlsx-files can get pretty big, so nodejs & full featured xlsx-modules can reach memory limits or just use more than is needed for that task. (--max-old-space-size & --stack_size can't help you all the time either)

hence these magnificent features:

• files are parsed with sax parser sax or node-expat
• get rows/cells each by callback or write them to a .tsv or .json file

Install

npm install xlsx-extract

The XML files of the format are parsed with sax-js by default.

If you want to use the faster node-expat parser please install it manually and use the {parser:"expat"} option. (Needs native compiling on the destination system)

npm install node-expat

Options

interface IXLSXExtractOptions {
    // sheet selection (provide one of the following)
    sheet_name?: string; // select by sheet name
    sheet_nr?: string; // default "1" - select by number of the sheet starting on 1
    sheet_id?: string; // select by sheet id, e.g. "1"
    sheet_rid?: string; // select by internal sheet rid, e.g. "rId1'
    sheet_all?: boolean; // default false - select all sheets
    // sax parser selection
    parser?: string; // default "sax" - 'sax'|'expat'
    // row selection
    ignore_header?: number; // default 0 - the number of header lines to ignore
    include_empty_rows?: boolean; // default false - include empty rows in the middle/at start
    // how to output sheet, rows and cells
    format?: string; // default array - convert to 'array'||'json'||'tsv'||'obj'
    // tsv output options
    tsv_float_comma?: boolean; // default false - use "," als decimal point for floats
    tsv_delimiter?: string; // default '\t' - use specified character to field delimiter
    tsv_endofline?: string; // default depending on your operating system (node os.EOL) e.g. '\n'
    // cell value formats
    raw_values?: boolean;  // default false - do not apply cell formats (get values as string as in xlsx)
    round_floats?: boolean; // default true - round float values as the cell format defines (values will be reported as parsed floats otherwise)
    date1904?: boolean;   // default false - use date 1904 conversion
    convert_values?: { // apply cell number formats or not (values will be reported as strings otherwise)
        ints?: boolean;  // rounds to int if number format is for int
        floats?: boolean;  // rounds floats according to float number format
        dates?: boolean;  // converts xlsx date to js date
        bools?: boolean; // converts xlsx bool to js boolean
    };
    // xlsx structure options
    workfolder?: string; // default 'xl' - the workbook subfolder in zip structure
}

Convenience API

    var XLSX = require('xlsx-extract').XLSX;

    //dump arrays
    new XLSX().extract('path/to/file.xlsx', {sheet_id:1}) // or sheet_name or sheet_nr
        .on('sheet', function (sheet) {
            console.log('sheet',sheet);  //sheet is array [sheetname, sheetid, sheetnr]
        })
        .on('row', function (row) {
            console.log('row', row);  //row is a array of values or []
        })
        .on('cell', function (cell) {
            console.log('cell', cell); //cell is a value or null
        })
        .on('error', function (err) {
            console.error('error', err);
        })
        .on('end', function (err) {
            console.log('eof');
        });

    //dump by row in tsv-format
    new XLSX().extract('path/to/file.xlsx', {sheet_id:1, format:'tsv'}) // or sheet_name or sheet_nr
        .on('sheet', function (sheet) {
            console.log('sheet', sheet);  //sheet is tsv sheetname sheetnr
        })
        .on('row', function (row) {
            console.log(row); //row is a tsv line
        })
        .on('cell', function (cell) {
            console.log(cell); //cell is a tsv value
        })
        .on('error', function (err) {
            console.error(err);
        })
        .on('end', function (err) {
            console.log('eof');
        });

    //convert to tsv-file (sheet info is not written to file)
    new XLSX().convert('path/to/file.xlsx', 'path/to/destfile.tsv')
        .on('error', function (err) {
            console.error(err);
        })
        .on('end', function () {
            console.log('written');
        })

    //convert to json-file (sheet info is not written to file)
    new XLSX().convert('path/to/file.xlsx', 'path/to/destfile.json')
        .on('error', function (err) {
            console.error(err);
        })
        .on('end', function () {
            console.log('written');
        })