LUKI NOTES

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...

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...

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...

The trick was unexpected and caught Bertolt off guard.

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...

Recently, I sought a simpler method to deploy and maintain Kubernetes clusters across various cloud providers. The goal was to use it for development purposes with the ability to manage the infrastructure and costs effortlessly. After exploring several options, I decided to experiment with Rancher. Rancher offers a comprehensive software stack for teams implementing container technology. It tackles both the operational and security hurdles associated with managing numerous Kubernetes clusters. Additionally, it equips DevOps teams with integrated tools essential for managing containerized workloads. Rancher also offers an open-source version, allowing free deployment within one's infrastructure. The Rancher platform can be deployed either as a Docker container or within a Kubernetes cluster utilizing the K3s engine. We can read the documentation on how to install Rancher on K3s using Helm . Rancher itself enables the creation and provisioning of Kubernetes clusters and ...

The last moments of Commander Erwin.

GitLab allows us to deploy CI/CD pipeline runners on our own resources within our environment. This option is available not only for the self-hosted plan but also for the cloud service plan (gitlab.com). With this setup, unlike GitHub Action, we can avoid incurring additional costs for extended pipeline runtime. This is because we can deploy the runner on an on-demand server and optimize its usage. GitLab CI offers several options for setting up resources to run CI/CD pipelines. A runner can be configured to handle jobs for specific groups or projects using designated tags. It can also be set to use different executors, such as Shell, Docker, Kubernetes, or VirtualBox. A comparison table of the supported executors is available in the executor documentation . Some executors offer greater flexibility and ease of use, while others may be more rigid but enhance server security. Installing the runner in our machine For example, we will deploy the runner on an Ubuntu serve...

The increasing demands of users for high-quality web services create the need to integrate various technologies into our application. This will cause the code base to grow larger, making maintenance more difficult over time. A microservices approach offers a solution, where the application is built by combining multiple smaller services, each with a distinct function. For example, one service handles authentication, another manages business functions, another maintains file uploads, and so on. These services communicate and integrate through a common channel. On the client side, users don't need to understand how the application is built or how it functions internally. They simply send a request to a single endpoint, and processes like authentication, caching, or database querying happen seamlessly. This is where an API gateway is effective. It handles user requests and directs them to the appropriate handler. There are several tools available for building an API gateway, su...

Recently, someone introduced me to a tool called Directus, which is used for building backend systems and defining data structures. This also reminded me of a product I reviewed about two years ago, which was also built using Directus. After doing some online research, I decided to test another headless CMS solution called Strapi. When we think of CMS platforms, names like WordPress, Joomla, or Moodle might come to mind. But what does 'headless' mean in this context? A headless CMS is a type of CMS that focuses solely on the backend system, without providing the frontend interface. It can generate the API endpoints, letting developers build the frontend or client-side application separately. However, this doesn't mean headless CMS platforms lack a user interface entirely. Most, like Directus and Strapi, include a UI tool (an administrator dashboard) for designing and managing the backend system and resources. After spending some time testing and reviewing Stra...

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...