Creating multi-content PDF export

This extensive tutorial will show how you can use pdfmake library, which is bundled with amCharts 5 plugin Exporting, to generate full page, multi-content report PDF documents.

Disclaimer

Majority of this tutorial is based on using pdfmake. It's an excellent third party library enabling generating PDF documents in JavaScript. Our aim is to walk you through basics of using pdfmake. For advanced usage, support, and community head over to pdfmake page.

The task

To start with, let's say we want to generate something like this:

Here's a live version:

See the Pen
amCharts 5: Multi-content export
by amCharts team (@amcharts)
on CodePen.0

Building a PDF

Preparing

Let's create a function, that will handle the exporting. It can be invoked with a press of a button, or on some other event.

function savePDF() {
// This is where the magic will be happening
}
function savePDF() {
// This is where the magic will be happening
}

Getting a pdfmake object

You already know that we will be using pdfmake to build our PDF.

It comes with the plugin Exporting, so we will need to import or load it first:

import * as am5exporting from "@amcharts/amcharts5/plugins/exporting";
<script src="https://cdn.amcharts.com/lib/5/plugins/exporting.js"></script>

Then create a plugin instance:

let exporting = am5plugins_exporting.Exporting.new(root, {
  menu: am5plugins_exporting.ExportingMenu.new(root, {})
});
var exporting = am5plugins_exporting.Exporting.new(root, {
  menu: am5plugins_exporting.ExportingMenu.new(root, {})
});

We'll grab a pdfmake object right out of the plugin's instance, using its getPdfmake() method:

function savePDF() {
  exporting.getPdfmake().then(function(pdfmake) {
     // pdfmake is ready
     // ...
  );
}
function savePDF() {
  exporting.getPdfmake().then(function(pdfmake) {
     // pdfmake is ready
     // ...
  );
}

Since pdfmake is loaded dynamically on-demand, the async accessor exporting.getPdfmake() returns a Promise, not the object itself. This is why we are using then() clause, which kicks in when pdfmake is loaded and ready.

All of the subsequent code in this tutorial will go inside this promise handler.

NOTEWhile we will need to create an exporting object for each chart individually, we only need one pdfmake object, so we'll do it for the first chart only.

Chart snapshots

Besides getting pdfmake object we have a few other asynchronous operations on our hands: getting snapshots of all the charts.

This is done via exporting object's export() method. Just like getPdfmake(), it returns a Promise.

Since we need all of those to create a document, let's combine all of them into a single Promise.all call.

function savePDF() {
  let exporting = am5plugins_exporting.Exporting.new(root, {
    menu: am5plugins_exporting.ExportingMenu.new(root, {})
  });
  
  let exporting2 = am5plugins_exporting.Exporting.new(root2, {
    menu: am5plugins_exporting.ExportingMenu.new(root2, {})
  });
  
  let exporting3 = am5plugins_exporting.Exporting.new(root3, {
    menu: am5plugins_exporting.ExportingMenu.new(root3, {})
  });
  
  let exporting4 = am5plugins_exporting.Exporting.new(root4, {
    menu: am5plugins_exporting.ExportingMenu.new(root4, {})
  });
  
  Promise.all([
    exporting.getPdfmake(),
    exporting.export("png"),
    exporting2.export("png"),
    exporting3.export("png"),
    exporting4.export("png")
  ]).then(function(res) { 
     // pdfmake and chart snapshots are ready
     // res[0] contains pdfmake instance
     // res[1] contains shapshot of chart 1
     // etc.
     let pdfMake = res[0];
  );
}
function savePDF() {
  var exporting = am5plugins_exporting.Exporting.new(root, {
    menu: am5plugins_exporting.ExportingMenu.new(root, {})
  });
  
  var exporting2 = am5plugins_exporting.Exporting.new(root2, {
    menu: am5plugins_exporting.ExportingMenu.new(root2, {})
  });
  
  var exporting3 = am5plugins_exporting.Exporting.new(root3, {
    menu: am5plugins_exporting.ExportingMenu.new(root3, {})
  });
  
  var exporting4 = am5plugins_exporting.Exporting.new(root4, {
    menu: am5plugins_exporting.ExportingMenu.new(root4, {})
  });
  
  Promise.all([
    exporting.getPdfmake(),
    exporting.export("png"),
    exporting2.export("png"),
    exporting3.export("png"),
    exporting4.export("png")
  ]).then(function(res) { 
     // pdfmake and chart snapshots are ready
     // res[0] contains pdfmake instance
     // res[1] contains shapshot of chart 1
     // etc.
     var pdfMake = res[0];
  );
}

MORE INFO For more about getting chart snapshots read here. To learn about Promise.all check this MDN article.

Document definition

Now that we have all of our async stuff loaded and ready, let's create a PDF document definition.

pdfmake uses a structured JavaScript object to describe the documents:

// pdfmake is ready
// Create document template
let doc = {
pageSize: "A4",
pageOrientation: "portrait",
pageMargins: [30, 30, 30, 30],
content: []
};
// pdfmake is ready
// Create document template
var doc = {
pageSize: "A4",
pageOrientation: "portrait",
pageMargins: [30, 30, 30, 30],
content: []
};

As you may already guessed, all content that needs to go into PDF document will be included as objects into content array.

MORE INFOThe document definition is described in great detail in pdfmake documentation. Make sure you read it for much more usage tips and options.

Headers and text

Now that we have our (blank) PDF document definition object ready, let's add some text to it.

doc.content.push({
text: "In accumsan velit in orci tempor",
fontSize: 20,
bold: true,
margin: [0, 20, 0, 15]
});

doc.content.push({
text: "Lorem ipsum dolor sit amet, consectetur adipiscing elit...",
fontSize: 15,
margin: [0, 0, 0, 15]
});
doc.content.push({
text: "In accumsan velit in orci tempor",
fontSize: 20,
bold: true,
margin: [0, 20, 0, 15]
});

doc.content.push({
text: "Lorem ipsum dolor sit amet, consectetur adipiscing elit...",
fontSize: 15,
margin: [0, 0, 0, 15]
});

NOTEThe margins in pdfmake margin definition do not start with top as in CSS, but rather from left and go clockwise: left, top, right bottom.

MORE INFOFor more information and options for adding text read here.

Charts

Adding images is similar to text.

We already have snapshots of our charts in res array, so we can start pushing those into document content.

doc.content.push({
image: res[1],
width: 530
});
doc.content.push({
image: res[1],
width: 530
});

width is important. Without it, your image might not fit into the page. The full width of the A4 page is 595.28 (Letter is 612).

Make sure you take document's margins into account when calculating allowed image width.

MORE INFOFor more info about adding images read here.

Tables

Now, let's add a table.

doc.content.push({
table: {
headerRows: 1,
widths: [ "*", "*", "*", "*" ],
body: [
[
{ text: "USA", bold: true },
{ text: "Japan", bold: true },
{ text: "France", bold: true },
{ text: "Mexico", bold: true }
],
[ "2500", "2500", "2200", "1200" ],
[ "800", "1200", "990", "708" ],
[ "2100", "2150", "900", "1260" ],
]
}
});
doc.content.push({
table: {
headerRows: 1,
widths: [ "*", "*", "*", "*" ],
body: [
[
{ text: "USA", bold: true },
{ text: "Japan", bold: true },
{ text: "France", bold: true },
{ text: "Mexico", bold: true }
],
[ "2500", "2500", "2200", "1200" ],
[ "800", "1200", "990", "708" ],
[ "2100", "2150", "900", "1260" ],
]
}
});

MORE INFOThis page in pdfmake documentation has more details about adding and formatting tables.

Columns

Next up: two charts set side by side.

For that we'll need to utilize content columns.

doc.content.push({
columns: [{
image: res[2],
width: 250
}, {
image: res[3],
width: 250
}],
columnGap: 30
});
doc.content.push({
columns: [{
image: res[2],
width: 250
}, {
image: res[3],
width: 250
}],
columnGap: 30
});

Columns work like mini-content: you just add regular content definition objects, except they will be laid out horizontally next to each other.

We can add any content to columns, mix and match them, like for example image and text:

doc.content.push({
columns: [{
image: res[4],
width: 150
}, {
stack: [{
text: "Maecenas congue leo vel tortor faucibus, non semper odio viverra...",
fontSize: 15,
margin: [0, 0, 0, 15]
}, {
text: "Fusce sed quam pharetra, ornare ligula id, maximus risus...",
fontSize: 15,
margin: [0, 0, 0, 15]
}],
width: "*"
}],
columnGap: 30
});
doc.content.push({
columns: [{
image: res[4],
width: 150
}, {
stack: [{
text: "Maecenas congue leo vel tortor faucibus, non semper odio viverra...",
fontSize: 15,
margin: [0, 0, 0, 15]
}, {
text: "Fusce sed quam pharetra, ornare ligula id, maximus risus...",
fontSize: 15,
margin: [0, 0, 0, 15]
}],
width: "*"
}],
columnGap: 30
});

MORE INFOAs usual, more details and options in pdfmake docs: columns and stacks of paragraphs.

Download & print

That's it. We're done configuring our document. Let's trigger download.

pdfmake has that included:

pdfMake.createPdf(doc).download("report.pdf");
pdfMake.createPdf(doc).download("report.pdf");

Or if we'd like to print it:

pdfMake.createPdf(doc).print();
pdfMake.createPdf(doc).print();

MORE INFOFor more options about how to handle final PDF document read this page of pdfmake documentation.

Full example

See the Pen
amCharts 5: Multi-content export
by amCharts team (@amcharts)
on CodePen.0

Alternative example

The following example uses am5.registry.rootElements global variable to automatically export all charts on page into a PDF:

See the Pen
Untitled
by amCharts team (@amcharts)
on CodePen.0

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