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I'm trying to generate a PDF using Puppeteer and insert there a Chart.js graph (but the whole PDF should be a text based - not a webpage screenshot). When I open the template I can see graph loaded, but in PDF there is just a blank space instead. I'm generating it like this:

async function generatePdf() {
  let data = { value: "myValue" };
  getTemplateHtml()
    .then(async (res) => {
      // Now we have the html code of our template in res object
      // you can check by logging it on console
      // console.log(res)
      console.log("Compiing the template with handlebars");
      const template = hbpile(res, { strict: true });
      // we have pile our code with handlebars
      const result = template(data);
      // We can use this to add dyamic data to our handlebas template at run time from database or API as per need. you can read the official doc to learn more /
      const html = result;
      // we are using headless mode
      const browser = await puppeteer.launch({ args: ["--no-sandbox"] });
      const page = await browser.newPage();
      // We set the page content as the generated html by handlebars
      await page.setContent(html);
      // We use pdf function to generate the pdf in the same folder as this file.
      await page.pdf({
        path: "output2.pdf",
        format: "A4",
        displayHeaderFooter: true,
        margin: {
          top: "2.5cm",
          right: "2.5cm",
          bottom: "2.5cm",
          left: "2.5cm",
        },
        headerTemplate: "<div></div>",
        footerTemplate:
          '<div style="width: 100%; font-size: 11px !important; overflow: auto; margin-left: 2.5cm; margin-right: 2.5cm; color: ghostwhite;"><span>TEST</span><a href="; style="float: right; color: #1E90FF; text-decoration: none;">www.test</a></div>',
      });
      await browser.close();
      console.log("PDF Generated");
    })
    .catch((err) => {
      console.error(err);
    });
}
generatePdf();

Thanks

I'm trying to generate a PDF using Puppeteer and insert there a Chart.js graph (but the whole PDF should be a text based - not a webpage screenshot). When I open the template I can see graph loaded, but in PDF there is just a blank space instead. I'm generating it like this:

async function generatePdf() {
  let data = { value: "myValue" };
  getTemplateHtml()
    .then(async (res) => {
      // Now we have the html code of our template in res object
      // you can check by logging it on console
      // console.log(res)
      console.log("Compiing the template with handlebars");
      const template = hb.pile(res, { strict: true });
      // we have pile our code with handlebars
      const result = template(data);
      // We can use this to add dyamic data to our handlebas template at run time from database or API as per need. you can read the official doc to learn more https://handlebarsjs./
      const html = result;
      // we are using headless mode
      const browser = await puppeteer.launch({ args: ["--no-sandbox"] });
      const page = await browser.newPage();
      // We set the page content as the generated html by handlebars
      await page.setContent(html);
      // We use pdf function to generate the pdf in the same folder as this file.
      await page.pdf({
        path: "output2.pdf",
        format: "A4",
        displayHeaderFooter: true,
        margin: {
          top: "2.5cm",
          right: "2.5cm",
          bottom: "2.5cm",
          left: "2.5cm",
        },
        headerTemplate: "<div></div>",
        footerTemplate:
          '<div style="width: 100%; font-size: 11px !important; overflow: auto; margin-left: 2.5cm; margin-right: 2.5cm; color: ghostwhite;"><span>TEST</span><a href="http://test." style="float: right; color: #1E90FF; text-decoration: none;">www.test.</a></div>',
      });
      await browser.close();
      console.log("PDF Generated");
    })
    .catch((err) => {
      console.error(err);
    });
}
generatePdf();

Thanks

• javascript
• chart.js
• puppeteer

Share Improve this question Follow asked Sep 1, 2020 at 16:54 o..oo..o 1,92177 gold badges3535 silver badges6565 bronze badges 2

• Hi, if you have, can you please share the node js and html code of this, I am trying to do a similar thing, and couldn't figure it out. Thanks a lot – Abhishek Soni Commented Aug 17, 2021 at 9:40
• See also How to create a bar chart image on nodejs without a browser?, puppeteer can't find the helpers of nodejs handlebars and using async await and .then together (you're not awaiting or returning your promise chain) – ggorlen Commented Apr 19, 2024 at 23:34

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1 Answer 1

Sorted by: Reset to default 9

You need to have Puppeteer wait for the Javascript to execute and render the graph.

You can supply a waitUntil option to page.setContent (doc):

await page.setContent(reuslt, {
    waitUntil: ["load","networkidle0"]
});

Also, you should disable animation on your chart by setting options.animation.duration to 0.

You haven't shared your HTML/Javascript so I can't say for sure, but if your Javascript still isn't executed then you can use waitForFunction to wait until your graph has loaded. See this answer for details.

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