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Command-Line Tools

With the availability of JS engines and the success of server-side platforms, it is feasible to build command-line tools for various workflows.

This demo covers a number of strategies for building standalone processors. The goal is to generate CSV output from an arbitrary spreadsheet file.

Deno​

deno compile generates a standalone executable that includes the entire JS runtime as well as user JS code.

When compiling, the --allow-read option must be specified to allow the script to read files from the filesystem with Deno.readFileSync.

Complete Example (click to show)

1) Save the following script to sheet2csv.ts:

sheet2csv.ts
/*! sheetjs (C) 2013-present SheetJS -- https://sheetjs.com */
// @deno-types="https://cdn.sheetjs.com/xlsx-latest/package/types/index.d.ts"
import * as XLSX from 'https://cdn.sheetjs.com/xlsx-latest/package/xlsx.mjs';
import * as cptable from 'https://cdn.sheetjs.com/xlsx-latest/package/dist/cpexcel.full.mjs';
XLSX.set_cptable(cptable);

/* Read and parse workbook */
const filename = Deno.args[0];
if(!filename) {
  console.error("usage: sheet2csv <filename> [sheetname]");
  Deno.exit(1);
}
const workbook = XLSX.readFile(filename);

/* Find worksheet */
const sheetname = Deno.args[1] || workbook.SheetNames[0];
if(!workbook.Sheets[sheetname]) {
  console.error(`error: workbook missing sheet ${sheetname}`);
  Deno.exit(1);
}

/* Generate CSV and print to stdout */
console.log(XLSX.utils.sheet_to_csv(workbook.Sheets[sheetname]));

2) Build sheet2csv with deno compile:

deno compile -r --allow-read sheet2csv.ts

sheet2csv is a generated executable that you can run.

NodeJS​

There are a few popular tools for compiling NodeJS scripts to CLI programs.

The demo script presents a friendly command line interface including flags:

$ ./xlsx-cli -h
Usage: xlsx-cli [options] <file> [sheetname]

Options:
  -V, --version            output the version number
  -f, --file <file>        use specified workbook
  -s, --sheet <sheet>      print specified sheet (default first sheet)
...

1) Download xlsx-cli.js

2) Install the dependencies:

yarn add https://cdn.sheetjs.com/xlsx-0.19.2/xlsx-0.19.2.tgz exit-on-epipe [email protected]

3) Follow tooling steps:

Run nexe and manually specify NodeJS version 14.15.3

npx nexe -t 14.15.3 xlsx-cli.js

This generates xlsx-cli or xlsx-cli.exe depending on platform.