write_carried_facts.json

The JSON file of the “A delivery note that knows its own order” example. Every line of the note carries the order it was picked for, the article code and the shelf it came off, and prints none of them. The place where the driver signs carries the round and the van, and one beside the fold tick carries nothing but its own place.

JSON 343 lines

This file is a request: an application sends it over the network to the server, which creates the PDF and sends it back. It makes the same page as the Rust and Python versions of this example. A request names every file it uses, never its content; the call carries the request and the files together. A font the server already holds, such as DejaVuSans, is named with nothing attached. Send the request to the address the API page gives.

What this example is for

A warehouse prints a note for the driver and keeps a record for itself. Three days later the signed sheet comes back, and somebody has to put it beside the record it belongs to. Printing the codes on the note would settle that in a moment, at the price of a column of machine words down a sheet a customer reads and signs.

What this example shows

Download the file The same example in Rust The same example in Python See what it creates 
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{
  "carried_facts": [
    { "name": "line 1", "facts": { "Article": "TBL-OAK-180", "Bin": "A-14-3", "Order": "SO-88412" } },
    { "name": "line 2", "facts": { "Article": "CHR-WAL-04", "Bin": "A-09-1", "Order": "SO-88412" } },
    { "name": "line 3", "facts": { "Article": "SBD-3DR-120", "Bin": "B-02-7", "Order": "SO-88451" } },
    { "name": "line 4", "facts": { "Article": "SHF-WAL-090", "Bin": "C-31-2", "Order": "SO-88451" } },
    { "name": "line 5", "facts": { "Article": "CST-STD-01", "Bin": "C-08-5", "Order": "SO-88463" } },
    { "name": "line 6", "facts": { "Article": "LMP-FLR-BRS", "Bin": "D-17-9", "Order": "SO-88463" } },
    { "name": "round", "facts": { "Round": "RT-2026-224", "Van": "DRV-118" } }
  ],
  "items": [
    {
      "type": "flow",
      "rect": { "llx": 72.0, "lly": 746.8, "urx": 523.0, "ury": 790.0 },
      "content": "A delivery note that knows which order it came from",
      "font": "DejaVuSans",
      "font_size": 18.0
    },
    {
      "type": "flow",
      "rect": { "llx": 72.0, "lly": 674.8, "urx": 523.0, "ury": 734.8 },
      "content": "Every line of the note below carries the order it was picked for, the article code and the shelf it came off, and prints none of the three. The line is drawn inside a marked run, and the run points at a list of facts held once in the file under the warehouse's own names. The sheet that comes back signed is therefore paired with the records it came from by reading the file, not by reading the paper.",
      "font": "DejaVuSans",
      "font_size": 10.0
    },
    {
      "type": "flow",
      "rect": { "llx": 72.0, "lly": 638.4, "urx": 523.0, "ury": 652.8 },
      "content": "The note the driver carries",
      "font": "DejaVuSans",
      "font_size": 12.0
    },
    {
      "type": "flow",
      "rect": { "llx": 72.0, "lly": 618.2, "urx": 523.0, "ury": 628.4 },
      "content": "Meunier & Filles, 14 rue des Tanneurs, Tours — delivered 13 August 2026",
      "font": "DejaVuSans",
      "font_size": 8.5,
      "color": [0.42, 0.42, 0.42]
    },
    {
      "type": "flow",
      "rect": { "llx": 72.0, "lly": 596.0, "urx": 372.0, "ury": 606.2 },
      "content": "Goods",
      "font": "DejaVuSans",
      "font_size": 8.5,
      "color": [0.42, 0.42, 0.42]
    },
    {
      "type": "flow",
      "rect": { "llx": 372.0, "lly": 596.0, "urx": 422.0, "ury": 606.2 },
      "content": "Qty",
      "font": "DejaVuSans",
      "font_size": 8.5,
      "align": "right",
      "color": [0.42, 0.42, 0.42]
    },
    {
      "type": "flow",
      "rect": { "llx": 422.0, "lly": 596.0, "urx": 523.0, "ury": 606.2 },
      "content": "Picked by",
      "font": "DejaVuSans",
      "font_size": 8.5,
      "align": "right",
      "color": [0.42, 0.42, 0.42]
    },
    {
      "type": "line",
      "from": { "x": 72.0, "y": 592.0 },
      "to": { "x": 523.0, "y": 592.0 },
      "stroke": { "width": 0.6, "color": [0.3, 0.3, 0.3] }
    },
    {
      "type": "flow",
      "rect": { "llx": 72.0, "lly": 568.6, "urx": 372.0, "ury": 580.0 },
      "content": "Oak dining table, 180 cm",
      "font": "DejaVuSans",
      "font_size": 9.5,
      "tag": "Line",
      "facts": "line 1"
    },
    {
      "type": "flow",
      "rect": { "llx": 372.0, "lly": 568.6, "urx": 422.0, "ury": 580.0 },
      "content": "1",
      "font": "DejaVuSans",
      "font_size": 9.5,
      "align": "right",
      "tag": "Line",
      "facts": "line 1"
    },
    {
      "type": "flow",
      "rect": { "llx": 422.0, "lly": 568.6, "urx": 523.0, "ury": 580.0 },
      "content": "MJ",
      "font": "DejaVuSans",
      "font_size": 9.5,
      "align": "right",
      "tag": "Line",
      "facts": "line 1"
    },
    {
      "type": "line",
      "from": { "x": 72.0, "y": 566.0 },
      "to": { "x": 523.0, "y": 566.0 },
      "stroke": { "width": 0.4, "color": [0.72, 0.72, 0.72] }
    },
    {
      "type": "flow",
      "rect": { "llx": 72.0, "lly": 550.6, "urx": 372.0, "ury": 562.0 },
      "content": "Dining chair, walnut",
      "font": "DejaVuSans",
      "font_size": 9.5,
      "tag": "Line",
      "facts": "line 2"
    },
    {
      "type": "flow",
      "rect": { "llx": 372.0, "lly": 550.6, "urx": 422.0, "ury": 562.0 },
      "content": "6",
      "font": "DejaVuSans",
      "font_size": 9.5,
      "align": "right",
      "tag": "Line",
      "facts": "line 2"
    },
    {
      "type": "flow",
      "rect": { "llx": 422.0, "lly": 550.6, "urx": 523.0, "ury": 562.0 },
      "content": "MJ",
      "font": "DejaVuSans",
      "font_size": 9.5,
      "align": "right",
      "tag": "Line",
      "facts": "line 2"
    },
    {
      "type": "line",
      "from": { "x": 72.0, "y": 548.0 },
      "to": { "x": 523.0, "y": 548.0 },
      "stroke": { "width": 0.4, "color": [0.72, 0.72, 0.72] }
    },
    {
      "type": "flow",
      "rect": { "llx": 72.0, "lly": 532.6, "urx": 372.0, "ury": 544.0 },
      "content": "Sideboard, three doors",
      "font": "DejaVuSans",
      "font_size": 9.5,
      "tag": "Line",
      "facts": "line 3"
    },
    {
      "type": "flow",
      "rect": { "llx": 372.0, "lly": 532.6, "urx": 422.0, "ury": 544.0 },
      "content": "1",
      "font": "DejaVuSans",
      "font_size": 9.5,
      "align": "right",
      "tag": "Line",
      "facts": "line 3"
    },
    {
      "type": "flow",
      "rect": { "llx": 422.0, "lly": 532.6, "urx": 523.0, "ury": 544.0 },
      "content": "PL",
      "font": "DejaVuSans",
      "font_size": 9.5,
      "align": "right",
      "tag": "Line",
      "facts": "line 3"
    },
    {
      "type": "line",
      "from": { "x": 72.0, "y": 530.0 },
      "to": { "x": 523.0, "y": 530.0 },
      "stroke": { "width": 0.4, "color": [0.72, 0.72, 0.72] }
    },
    {
      "type": "flow",
      "rect": { "llx": 72.0, "lly": 514.6, "urx": 372.0, "ury": 526.0 },
      "content": "Wall shelf, 90 cm",
      "font": "DejaVuSans",
      "font_size": 9.5,
      "tag": "Line",
      "facts": "line 4"
    },
    {
      "type": "flow",
      "rect": { "llx": 372.0, "lly": 514.6, "urx": 422.0, "ury": 526.0 },
      "content": "4",
      "font": "DejaVuSans",
      "font_size": 9.5,
      "align": "right",
      "tag": "Line",
      "facts": "line 4"
    },
    {
      "type": "flow",
      "rect": { "llx": 422.0, "lly": 514.6, "urx": 523.0, "ury": 526.0 },
      "content": "PL",
      "font": "DejaVuSans",
      "font_size": 9.5,
      "align": "right",
      "tag": "Line",
      "facts": "line 4"
    },
    {
      "type": "line",
      "from": { "x": 72.0, "y": 512.0 },
      "to": { "x": 523.0, "y": 512.0 },
      "stroke": { "width": 0.4, "color": [0.72, 0.72, 0.72] }
    },
    {
      "type": "flow",
      "rect": { "llx": 72.0, "lly": 496.6, "urx": 372.0, "ury": 508.0 },
      "content": "Coat stand",
      "font": "DejaVuSans",
      "font_size": 9.5,
      "tag": "Line",
      "facts": "line 5"
    },
    {
      "type": "flow",
      "rect": { "llx": 372.0, "lly": 496.6, "urx": 422.0, "ury": 508.0 },
      "content": "2",
      "font": "DejaVuSans",
      "font_size": 9.5,
      "align": "right",
      "tag": "Line",
      "facts": "line 5"
    },
    {
      "type": "flow",
      "rect": { "llx": 422.0, "lly": 496.6, "urx": 523.0, "ury": 508.0 },
      "content": "SD",
      "font": "DejaVuSans",
      "font_size": 9.5,
      "align": "right",
      "tag": "Line",
      "facts": "line 5"
    },
    {
      "type": "line",
      "from": { "x": 72.0, "y": 494.0 },
      "to": { "x": 523.0, "y": 494.0 },
      "stroke": { "width": 0.4, "color": [0.72, 0.72, 0.72] }
    },
    {
      "type": "flow",
      "rect": { "llx": 72.0, "lly": 478.6, "urx": 372.0, "ury": 490.0 },
      "content": "Floor lamp, brushed steel",
      "font": "DejaVuSans",
      "font_size": 9.5,
      "tag": "Line",
      "facts": "line 6"
    },
    {
      "type": "flow",
      "rect": { "llx": 372.0, "lly": 478.6, "urx": 422.0, "ury": 490.0 },
      "content": "3",
      "font": "DejaVuSans",
      "font_size": 9.5,
      "align": "right",
      "tag": "Line",
      "facts": "line 6"
    },
    {
      "type": "flow",
      "rect": { "llx": 422.0, "lly": 478.6, "urx": 523.0, "ury": 490.0 },
      "content": "SD",
      "font": "DejaVuSans",
      "font_size": 9.5,
      "align": "right",
      "tag": "Line",
      "facts": "line 6"
    },
    {
      "type": "line",
      "from": { "x": 72.0, "y": 476.0 },
      "to": { "x": 523.0, "y": 476.0 },
      "stroke": { "width": 0.4, "color": [0.72, 0.72, 0.72] }
    },
    {
      "type": "line",
      "from": { "x": 323.0, "y": 456.0 },
      "to": { "x": 523.0, "y": 456.0 },
      "stroke": { "width": 0.5, "color": [0.3, 0.3, 0.3] },
      "tag": "Signature",
      "facts": "round"
    },
    {
      "type": "flow",
      "rect": { "llx": 323.0, "lly": 442.8, "urx": 523.0, "ury": 453.0 },
      "content": "Signed on delivery",
      "font": "DejaVuSans",
      "font_size": 8.5,
      "align": "right",
      "color": [0.42, 0.42, 0.42]
    },
    {
      "type": "line",
      "from": { "x": 54.0, "y": 561.0 },
      "to": { "x": 64.0, "y": 561.0 },
      "stroke": { "width": 0.4, "color": [0.72, 0.72, 0.72] }
    },
    {
      "type": "flow",
      "rect": { "llx": 72.0, "lly": 402.4, "urx": 523.0, "ury": 416.8 },
      "content": "What travels under the page",
      "font": "DejaVuSans",
      "font_size": 12.0
    },
    {
      "type": "flow",
      "rect": { "llx": 72.0, "lly": 344.4, "urx": 523.0, "ury": 392.4 },
      "content": "Seven lists of facts travel with this sheet: one against each of the six lines, and one at the point where the driver signs, which carries the round and the van. Not one letter of any of them is drawn. A list is written once in the file and pointed at from the page, so a list that belongs to several places is held once and marked as often as it is needed.",
      "font": "DejaVuSans",
      "font_size": 10.0
    },
    {
      "type": "flow",
      "rect": { "llx": 72.0, "lly": 312.0, "urx": 523.0, "ury": 326.4 },
      "content": "The mark that carries nothing",
      "font": "DejaVuSans",
      "font_size": 12.0
    },
    {
      "type": "flow",
      "rect": { "llx": 72.0, "lly": 266.0, "urx": 523.0, "ury": 302.0 },
      "content": "The short stroke in the left margin is where the sheet is folded for a window envelope, and a mark of its own is put in the page beside it, under a name and with no facts at all. A place is sometimes all there is to say.",
      "font": "DejaVuSans",
      "font_size": 10.0
    },
    {
      "type": "flow",
      "rect": { "llx": 72.0, "lly": 213.6, "urx": 523.0, "ury": 246.0 },
      "content": "What a list holds is the caller's business: an order number here, an article code in a catalogue, a state against a box on a form. The library neither reads these names nor acts on them — it writes them down and ties them to what was drawn.",
      "font": "DejaVuSans",
      "font_size": 9.0,
      "color": [0.42, 0.42, 0.42]
    }
  ]
}