tessera_pdf

PDF export for the tessera pivot-table engine.

PdfCubeExporter writes a CubeLayout (the expanded rows and columns exactly as shown) as a paginated document: merged group headers in the "rotated L" shape, one column per aggregate under each column entry, subtotals on the group's own row, fills and fonts from the engine's CubeExportTheme. Pages break only on grid lines; the header band and the row header repeat on every page like a spreadsheet's print titles. The grid is scaled to fit the page width down to a minimum scale, and tiled across pages beyond that (fitToWidth, minScale). A minimal page header and footer take three texts each with {title}, {page}, {pages} and {date} placeholders. Labels and numbers come from TesseraStrings, so the export is localized like the widgets.

Fonts: pass TrueType files as PdfFonts — they are embedded (subsetted) and their metrics size the columns exactly. Without them the built-in Helvetica is used, which covers Western European characters only.

Pure Dart on package:pdf, no Flutter — servers, CLIs and apps alike.

import 'package:tessera_pdf/tessera_pdf.dart';

final bytes = await PdfCubeExporter(
  strings: TesseraStrings.forLanguage('hu')!,
  theme: CubeExportTheme.brand(primary: 0xFF00695C),
  fonts: PdfFonts(regular: notoRegular, bold: notoBold),
  pageSetup: const PageSetup(size: PageSize.a4, orientation: PageOrientation.landscape),
  footer: const PdfPageText(left: '{date}', right: '{page} / {pages}'),
).export(cube.layout, title: 'Sales by region');

export is asynchronous and returns the PDF as a Future<Uint8List> (font embedding in package:pdf is async); the other exporters are synchronous.

User guide: github.com/nagylzs/tessera/docs — data sources, schema, cubes, aggregates, filters, the expression language, widgets, theming, export, localization, saving, large data.

Example

example/main.dart reads example/sales.csv, builds a region/country × year/quarter cube with every region expanded and writes it as sales_pivot.pdf, using Noto Sans from /usr/share/fonts/noto when present:

dart run example/main.dart [input.csv] [output.pdf] [font directory]

License

MIT — see LICENSE. Author: László Zsolt Nagy.