@zenuinebit/report-export

CSV and Excel (.xlsx) export for tables and for @zenuinebit/gst-report reports. No runtime dependencies besides the report types; works in Node and the browser (you get a string or a Uint8Array and decide how to save it).

import { table, toCSV, toXLSX, gstReportTables, XLSX_MIME } from "@zenuinebit/report-export";

const sales = table("Sales", rows, [
  { header: "Invoice", value: "number" },
  { header: "Date",    value: "date",   type: "date" },     // "YYYY-MM-DD"
  { header: "Qty",     value: "qty",    type: "number" },
  { header: "Amount",  value: "amount", type: "money" },    // integer minor units
]);

toCSV(sales, { bom: true });                       // string; the BOM makes Excel read UTF-8 correctly
const bytes = toXLSX([sales, anotherTable]);       // Uint8Array, one sheet per table

// Browser download
const url = URL.createObjectURL(new Blob([bytes], { type: XLSX_MIME }));

// Node
await fs.writeFile("sales.xlsx", bytes);

// A whole GST report: Summary, B2B, B2CL, B2CS, By rate, HSN, Invoices
await fs.writeFile("gst-april.xlsx", toXLSX(gstReportTables(report)));

Column types: text (default), number, money (integer minor units, written as 1234.56), date (YYYY-MM-DD).

Good to know

• Money stays a number in Excel. money cells are real numeric cells with a #,##0.00 format, so sums and filters work. In CSV they are plain decimals. Use currencyDigits for currencies without 2 decimals.
• Spreadsheet formula safety. In CSV, text starting with =, +, - or @ gets a leading ' so Excel cannot run it as a formula (turn off with formulaGuard: false). Numbers are never altered. In XLSX all text is stored as plain strings.
• CSV follows RFC 4180: fields with commas, quotes or line breaks are quoted, lines end with CRLF. delimiter: ";" is available for locales that need it.
• XLSX sheets have a bold, frozen header row and sized columns. Sheet names are made valid (31 characters, no []:*?/\) and unique.
• The .xlsx is written without compression (store only), which every spreadsheet program reads. It has been opened with openpyxl and checked with unzip -t.

Not included: styling beyond the header, formulas, multiple header rows, merged cells, charts, and reading files.