Handling PDF Generation in Web Service

If we are building a website that requires a PDF generation feature, there are several options for implementing it based on the use cases or user requirements. First, we can generate the PDF on the client side using any available client library. It is suitable if the use case is to print out some data that is already available inside certain website components, and we want to maintain the styles of the components in the document. Second, we can do it fully in the back-end using any library available, such as PDF-lib, jsPDF, and so on. This approach is suitable if we want to keep the data processing or any related business functions in the back-end server. This second approach might have disadvantages, such as the difficulty of maintaining the design assets and styles which are already on our website. Third, it is using a hybrid approach, where certain processes are handled on the client side, and some are handled on the back-end.

In this post, I want to discuss more about the hybrid approach, why the hybrid approach can be beneficial and how we can implement it. The scenario is that we want to maintain the design of our website or product in the document generated. On the other hand, we want to keep certain business processes in the back-end. We want to let our frontend developer design and generate the document content while the back-end developer focuses on the data generation and the PDF creation. So, how does it actually work?

On the client side, we need to set up a private page or endpoint where the back-end data will be loaded and filled into the web page. This page should be private or require a certain access mechanism so that it is not publicly available to end users. Then, on the back-end, we utilise a tool such as Pupetteer or Playwright, which is shipped with a browser engine and can render a web page and print the result into a PDF. The web page generation actually can be done in the back-end using a certain HTML templating library such as Handlebars. But still, that could be more difficult for us to maintain the desired design.

To be clearer with this idea, we can see the following diagram. This diagram shows how a user from the client side can trigger the PDF generation with the hybrid approach.

Comments

Deliver SaaS According Twelve-Factor App

If you haven't heard of the twelve-factor app , it gives us a recommendation or a methodology for developing SaaS or web apps structured into twelve items. The recommendation has some connections with microservice architecture and cloud-native environments which become more popular today. We can learn the details on its website . In this post, we will do a quick review of the twelve points. One Codebase Multiple Deployment We should maintain only one codebase for our application even though the application may be deployed into multiple environments like development, staging, and production. Having multiple codebases will lead to any kinds of complicated issues. Explicitly State Dependencies All the dependencies for running our application should be stated in the project itself. Many programming languages have a kind of file that maintains a list of the dependencies like package.json in Node.js. We should also be aware of the dependencies related to the pla...

Rangkaian Sensor Infrared dengan Photo Dioda

Keunggulan photodioda dibandingkan LDR adalah photodioda lebih tidak rentan terhadap noise karena hanya menerima sinar infrared, sedangkan LDR menerima seluruh cahaya yang ada termasuk infrared. Rangkaian yang akan kita gunakan adalah seperti gambar di bawah ini. Pada saat intensitas Infrared yang diterima Photodiode besar maka tahanan Photodiode menjadi kecil, sedangkan jika intensitas Infrared yang diterima Photodiode kecil maka tahanan yang dimiliki photodiode besar. Jika tahanan photodiode kecil maka tegangan V- akan kecil . Misal tahanan photodiode mengecil menjadi 10kOhm. Maka dengan teorema pembagi tegangan: V- = Rrx/(Rrx + R2) x Vcc V- = 10 / (10+10) x Vcc V- = (1/2) x 5 Volt V- = 2.5 Volt Sedangkan jika tahanan photodiode besar maka tegangan V- akan besar (mendekati nilai Vcc). Misal tahanan photodiode menjadi 150kOhm. Maka dengan teorema pembagi tegangan: V- = Rrx/(Rrx + R2) x Vcc V- = 150 / (1...

Configuring Swap Memory on Ubuntu Using Ansible

If we maintain a Linux machine with a low memory capacity while we are required to run an application with high memory consumption, enabling swap memory is an option. Ansible can be utilized as a helper tool to automate the creation of swap memory. A swap file can be allocated in the available storage of the machine. The swap file then can be assigned as a swap memory. Firstly, we should prepare the inventory file. The following snippet is an example, you must provide your own configuration. [server] 192.168.1.2 [server:vars] ansible_user=root ansible_ssh_private_key_file=~/.ssh/id_rsa Secondly, we need to prepare the task file that contains not only the tasks but also some variables and connection information. For instance, we set /swapfile as the name of our swap file. We also set the swap memory size to 2GB and the swappiness level to 60. - hosts: server become: true vars: swap_vars: size: 2G swappiness: 60 For simplicity, we only check the...

Free Cloud Services from UpCloud

Although I typically deploy my development environment or experimental services on UpCloud , I do not always stay updated on its announcements. Recently, I discovered that UpCloud has introduced a new plan called the Essentials plan, which enables certain cloud services to be deployed at no cost. The complimentary services are generally associated with network components or serve as the foundation for other cloud services. This feature is particularly useful when retaining foundational services, such as a load balancer, is necessary, while tearing down all services and reconfiguring the DNS and other application settings each time we temporarily clean up infrastructure to reduce costs is undesirable. When reviewing the service specifications of the cloud services in the Essentials plan, they appear to be very similar to those in the Development plan. The difference in service levels is unclear, but it could be related to hardware or resource allocation. For instance, the loa...

Deploying a Web Server on UpCloud using Terraform Modules

In my earlier post , I shared an example of deploying UpCloud infrastructure using Terraform from scratch. In this post, I want to share how to deploy the infrastructure using available Terraform modules to speed up the set-up process, especially for common use cases like preparing a web server. For instance, our need is to deploy a website with some conditions as follows. The website can be accessed through HTTPS. If the request is HTTP, it will be redirected to HTTPS. There are 2 domains, web1.yourdomain.com and web2.yourdomain.com . But, users should be redirected to "web2" if they are visiting "web1". There are 4 main modules that we need to set up the environment. Private network. It allows the load balancer to connect with the server and pass the traffic. Server. It is used to host the website. Load balancer. It includes backend and frontend configuration. Dynamic certificate. It is requ...

Why Hashicorp Vault Can Be Important

As I have been working on many software projects and teams, I see that sharing credentials among developers is a common thing. Sometimes, developers store credentials in a file where everyone in the team can access them just to streamline the development process. But, I was also wondering how to maintain the security of the software or data managed while the credentials are accessible to everyone. How can we monitor the usage, make sure that no one in the team uses the credentials differently than they're supposed to be, or renew the credentials with ease? Hashicorp Vault is one of the solutions in the market that can answer that question. There are three main problems that Vault solves. The first is called secret sprawl where the credentials are spread everywhere to many individuals. Then, it becomes difficult when someone leave the team and we have to renew the existing credentials to secure the access. Vault can provide a mechanism to centralize the credentials storage, p...

LUKI NOTES

Search This Blog