There are plenty of APIs and external services for generating PDF documents. But what if you want to keep the process within your server and have it without any additional costs? So in this tutorial, I will show you how you can install Gotenberg on your own server and create a workflow in n8n to generate PDF documents from HTML files. If you haven't installed n8n yet, you can go to my tutorial in the previous video - link in the description. Let's get started! So let's see first what we want to achieve here. I've prepared example code of an invoice, and we want to convert this invoice into an actual PDF file. So after executing the workflow, we should have in output the PDF file which we can download or process or even send to the customer. It depends on what you want to do. So this is how the output looks like, and let's see how we can do it. To better understand how Gotenberg works, it's good to check the live demo that is provided by Gotenberg in documentation.

So we have a URL where we can send the request with our parameters and see how the particular endpoints work. So here is the example invoice that you've already seen in this tutorial, and we want to convert this website into PDF, so let's build the workflow. We need to take HTTP Request node and of course adjust the parameters. We want to make a POST request to the specific endpoint, which is convert/url. And in the body, we need to add the specific URL of the website that we want to convert into PDF. In our case, it's the address of the invoice. So we want to copy this address and paste it into the body of the node. Then we can click execute node, wait a few seconds, and after that, we should have the file that can be downloaded. And this is, of course, our website which we wanted to convert into PDF. Let's see now how we can install Gotenberg on our own server to create PDF files with a local address.

So installation can be done with Docker Compose, and this is actually super simple to do. So we have a few lines of code that we need to paste into the docker-compose file. To be precise: in this example, I will actually take only the last two lines of this code and paste them into the existing docker-compose file. So go to your terminal and log in to your server. Taking into account that you followed my previous tutorial on how to install n8n, you need to change the directory to n8n-docker-caddy and then you need to edit the docker-compose file with the nano editor. Now simply paste those two lines, for example, under the n8n service, and you can save and close this file. Now you need to use three commands that you usually use by updating your n8n, so the first one is docker compose pull, the second one is docker compose down, and the third one: docker compose up -d.

After this operation, Gotenberg should be fully installed on your server, and we can build the workflow. So, I already have an HTML node in my workflow where I have the code of my invoice. And as you can see, the source code is under the key HTML in the JSON file. Now we need to create the index.html file that can be further processed by Gotenberg. So, I will use the Move Binary Data node, and I will rename it. In the mode section, I will choose JSON to Binary, and I will uncheck the Convert All Data switch. In the Source Key, it's very important to type html. Now you need to add two options: the first one is File Name, and in this field, type index.html, and as the second option, you need to add the switch Use Raw Data and simply turn it on. Now it's time to make the actual call to Gotenberg, so for this purpose, you need to find the HTTP Request node in the n8n library.

and put it on the canvas. As a method, you need to choose POST and paste here the endpoint of the Gotenberg API. Please note that I use right now the convert/html endpoint - you can find the details in the description of this video. Turn on the switch Send Body and as a Content Type, you need to choose Form-Data. Now you need to only point the node to the actual index.html file, which is the binary data. To keep my workflow clean, I will just rename this node, and I will close this window. The last step is to change the extension of the file to PDF. I will use code notes for this purpose, and I will paste there two lines of code. I have already prepared those two lines of code, and you can find them also in the description. The first line changes the name and extension of the file to result.pdf, and the second line returns this file. Now I will only copy and paste this node to the actual workflow, connect the nodes, and I can save the workflow.

And everything is ready! We can now execute the workflow to see what happens. When everything is fine, after a few seconds, the workflow should be completed, and as an output, we should have the PDF file, which is the invoice that we coded in HTML. Now we can download the file and check if everything is correct. And yes, in our case, everything looks fine - the invoice has been converted into PDF just like we want it to be. The great thing about Gotenberg is the fact that you can play with the parameters. For example, you can change the size of the site or add the footer or the header. All parameters that you can use to customize your PDFs you can find in Gotenberg documentation (link in the description). Now let's switch to our workflow and let's modify a bit our PDF and play with those options. I want my invoice to be in landscape mode, and I want to make it smaller. Of course, it doesn't make much sense, but I just want to show you how those parameters work.

So, I will add two parameters: the first one is called landscape, and I will set the value to true, and the second one is scale, and I will set the value to 0.5. Now we can execute the workflow, wait a few seconds, and after that, we should be able to preview our PDF, which in our case is, of course, in landscape mode, and the invoice is pretty small - actually half the size that it was before. So, yeah, that's how you can play with Gotenberg parameters. Thank you very much for watching! If you like this video, give a thumbs up, subscribe to my channel and to my newsletter (link in the description), and see you in the next video. Bye!

Generate PDFs in n8n with Gotenberg (for free!)

Generate PDFs in n8n with Gotenberg (for free!)