13. Preview, export and rendering

Preview PDF

Preview PDF renders your design to a real PDF in the browser, using the same engine as the render service, and shows it in a window.

The PDF preview window

The preview window shows:

the page count and how long the render took, for example 3 pages · 180 ms,
Refresh, to render again after changes, and Download PDF,
a list of warnings under the PDF, if any. Each warning names the element and the problem. See what warnings mean.

Close the preview with Close (Esc) or the Esc key.

How the preview differs from a real render

The designer has no data, so the preview uses placeholder mode:

In the preview	In a real render
Bindings show their preview text, or `{{field}}` when there is none	Bindings are replaced by the data
Tables and repeaters show 3 placeholder rows (2 groups × 2 rows when grouped)	One row per data item
Visible if counts as true, so every element shows	Elements show only when their condition is true
A checkbox is checked only when Checked if is literally `true`	Checked when the condition is true
A barcode encodes its preview text, or a valid sample value for its format	Encodes the data
Every page carries a light PREVIEW watermark	No watermark with a valid license (Licensing)
An image bound to data shows a gray box labeled with the binding	Shows the image
`page`, `pages` and `now` are real	Real

Everything else is identical: fonts, sizes, positions, wrapping, borders, page size, headers, footers and page breaks. To check how a long table breaks across pages, render with real data (see below), or temporarily raise Min. rows on the table.

Tip: Use Show expressions instead of preview text ({ } in the toolbar) to check all your bindings at once on the canvas.

Saving and exporting templates

Action	What happens
Save (Ctrl/Cmd+S)	The designer gives the template to your application, which stores it, for example as the BOL template for a warehouse. A Saved message confirms it
Export template JSON	Downloads the template as `<name>.json`
Open template JSON	Loads a `.json` template file. Invalid files are rejected with a message such as Invalid template: page — Required

A template file contains the whole design: page setup, bands, elements, named styles, embedded images and custom fonts. It contains no customer data.

Tip: Export a copy before making big changes. Template files are plain text and can be stored in version control.

Rendering PDFs with data

Your WMS, ERP or another system produces the final PDFs by sending the template and the data to the render service. Usually this is automatic, for example when a shipment is confirmed. The service returns the PDF.

For testing, you can render a template yourself with curl (ask your administrator for the address):

curl -sS -X POST http://localhost:8080/api/v1/render \
  -H 'Content-Type: application/json' \
  -d "{\"template\": $(cat bol.json), \"data\": $(cat bol-data.json)}" \
  -o bol.pdf -D -

The -D - part prints the response headers:

Header	Meaning
`X-Page-Count`	Number of pages
`X-Render-Warnings`	Number of warnings, such as missing images or expression problems. 0 is what you want
`X-License-Status`	`valid` = clean output. Anything else (`trial`, `expired`, `missing`, `invalid`) means watermarked

To see the warning texts, add ?format=json to the address. The response then contains the PDF as base64 plus a warnings list.

Batches: one copy per record

To print many documents at once, such as all BOLs for a day's loads or a label for every carton, set up the template once and send a list:

On the Report tab, under Records, set One copy per to the list's path, for example shipments.
Design the document for one record. Inside, bindings refer to the record directly: {{ bolNumber }}, not {{ shipments[0].bolNumber }}.
Your system sends { "shipments": [ {…}, {…}, {…} ] }.

The PDF contains one complete copy per record, one after another. In each copy:

{{ page }} and {{ pages }} restart: the second BOL says "Page 1 of 2", not "Page 4 of 5".
recordIndex is the copy's number (from 0), and record is its data.
Report header and footer print once per copy.

Note: The preview in the designer shows a single copy.

Document properties

On the Report tab, under Document, you can set the PDF's PDF title, Author, Subject and Keywords. PDF viewers show these in the document properties, and the title appears in the viewer's title bar. The title can contain bindings: Bill of Lading {{ bolNumber }}.