The Case of the Mistimed Python Script
By Josh Williams
February 19, 2025
“Time isn’t working right!” said a message from a client on their internal chat.
My efforts to catch a spot as an extra in a Doctor Who episode have thus far been fruitless, so I jumped in to reply to that message. Just in case.
The follow-up had more detail: “I’ve set something to run at 7:30 AM every morning, but it runs at 2:30 AM instead. Time zone is right. I can’t figure out what’s wrong.”
Dang, the screen debut will have to wait. But at least this is a mystery I can solve.
The hypothesis offered up was that a Python script was getting the time wrong, but it turns out Python doesn’t do the scheduling here. Rather, it’s just plain ol’ cron, so all eyes are on that now.
First, the obvious: It’s running early, not late. So it’s not a situation where it’s running for about 5 hours and appearing later than desired. I mean, it could possibly be taking 19 hours to run and finishing at 2:30 the next day, but at a glance it’s clearly not taking that long. It’s just running at the wrong time.
Let’s double check what cron is actually set to do.
30 7 * * * python3 /home/data/process/something.py
Alright. So clearly cron is set for 7:30 but running that at the wrong time. That’s …
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Place Labels in Cesium using Vector Data Tiles
By Dmitry Kiselev
February 13, 2025
Cesium is like an IKEA globe: it can do almost anything, but you have to put it together yourself. One major missing feature is labels for cities. Compare the default views of Google Earth and Cesium, and you’ll notice this immediately.
Left: Google Earth default view, with labels and state lines. Right: Cesium default view, with no labels or markers.
If you’re reading this post, you might be able to find any major U.S. city without any clues, but most people can’t. You can overlay imagery that includes labels as part of the image, but this approach has a significant drawback: as soon as you rotate the view away from north-up, the labels become difficult to read.
In Google Earth, this issue is handled using vector data overlays. Labels, borders, and other similar elements are examples of how useful vector overlays can be.
Cesium also supports vector features such as labels, polylines, and polygons. You can create them manually or use CZML or KML to add such features to a scene. If you use KML, Cesium translates it internally, but the result is the same. Vector features have distinct advantages for 3D geographic data, with …
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Django and Mojolicious: a quick comparison of two popular web frameworks
By Marco Pessotto
February 6, 2025
Recently I’ve been working on a project with a Vue front-end and two back-ends, one in Python using the Django framework and one in Perl using the Mojolicious framework. So, it’s a good time to spend some words to share the experience and do a quick comparison.
Previously I wrote a post about Perl web frameworks, and now I’m expanding the subject into another language.
Django was chosen for this project because it’s been around for almost 20 years now and provides the needed maturity and stability to be long-running and low-budget. In this regard, it has proved a good choice so far. Recently it saw a major version upgrade without any problems to speak of. It could be argued that I should have used the Django REST Framework instead of plain Django. However, at the time the decision was made, adding a framework on top of another seemed a bit excessive. I don’t have many regrets about this, though.
Mojolicious is an old acquaintance. It used to have fast-paced development but seems very mature now, and it’s even been ported to JavaScript.
Both frameworks have just a few dependencies (which is fairly normal in the Python world, but not in the Perl …
perl python django mojolicious catalyst
Reducing page load times: Cloudflare and caching with ASP.NET
By Juan Pablo Ventoso
January 14, 2025
When designing the architecture for a new website, it’s important to keep caching in mind. Caching allows you to store a copy of the pages or resources used by your web application in your local browser. Content distribution networks such as Cloudflare also leverage cache directives to distribute content to users more efficiently.
If we are going to use response caching on our web application, we should not include anything that depends on the identity context for the user in the page content in the response. Instead, we should render the same content to every user that hits the same URL. If we include any identity-specific content, the CDN will reuse it for other requests, which is a security and privacy risk.
A simple example is an ecommerce site where the customer logs in to make a purchase: If the homepage shows the user name and icon at the top bar, that content should be rendered from a non-cached request. Otherwise, CDN caching will show the same user and icon to other visitors. And worse: depending on the validations applied to the website, the profile page could even display personal information to other users!
When dealing with these situations, I often rely on …
dotnet aspdotnet csharp cloudflare
Learning Vue 3 composables by creating an invoice generator
By Bimal Gharti Magar
January 6, 2025
The latest major version of Vue, Vue 3, has new features that are not present in Vue 2, such as Teleport, Suspense, and support for multiple root elements per template. Vue 3 provides smaller bundle sizes, better performance, better scalability, and better TypeScript IDE support.
What are Vue 3 composables?
Writing repetitive code can be a real pain in the frontend development realm. We can use Vue 3 composables to encapsulate and reuse stateful logic in our components. In this blog post, we will look at how we can use composables to reuse business logic by building an invoice generator.
An invoice generator, simply said, is an application that creates and manages invoices. We will focus on creating Vue 3 composables to properly separate business logic while reusing it across different features.
Core functionalities for invoice generator
- Adding, editing, and removing invoices and items
- Calculating totals with discounts, taxes, and shipping
- Generating PDF invoices
To implement these functionalities, we’ll focus on:
- Creating composables to handle business logic
- Reusing this logic across features and components
Prerequisites
Basic understanding of:
- Vue 3 and Composition …
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Studying “The Mythical Man-Month” in Collaboration with a Client
By TJ Christofferson
December 23, 2024
Here at End Point we did an enlightening and fun eleven-week study group in collaboration with one of our clients. We worked through Frederick Brooks Jr.’s book The Mythical Man-Month: Essays on Software Engineering, which was originally published in 1975, with an expanded edition published in 1995. In certain ways this book is still applicable to our time, and it was a delight to discuss it in a structured study group with coworkers and peers. This particular study group even piqued the curiosity of the owners of both our companies who participated throughout the course!
As part of our effort to continually improve our abilities and awareness, and thus build a strong technical company culture, End Point has done many study groups over the years, such as the Ruby Fight Club and the You Don’t Know JS study group. Participation in these groups is voluntary, and they have covered a range of other topics including PostgreSQL, terminal fluency skills, and regular expressions. The opportunity to step away from regular work duties for an hour during the week, and to have meaningful discourse between coworkers has been invaluable for building relationships across teams.
For this …
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Migration from Struts 1 to Struts 2
By Kürşat Kutlu Aydemir
October 4, 2024
Apache Struts is an open source web framework. Struts 1 was first released in 2000 and its latest version (1.3.10) was released in December 2008, marking the EOL of Struts 1. So Struts 1 is an ancient, dead version. Organizations still using it need to move away from Struts 1.
Apache adapted the WebWork framework as Struts 2. Its architecture significantly differs from that of Struts 1. There are key points and obvious differences provided by Apache to cover a migration plan from Struts 1 to Struts 2.
The market share of Apache Struts is around 0.01%, which gives relatively lower relevance to Apache Struts. However, there are companies still using Apache Struts 1 in their legacy applications, which may not be counted in market share statistics.
A Comparison of Struts 1 and Struts 2
Struts 1 and Struts 2 differ significantly in their approach to handling web requests. Struts 1 follows a more rigid structure where Action classes must extend an abstract base class, limiting flexibility. In contrast, Struts 2 is more dynamic, allowing Action classes to implement interfaces or even function as simple POJOs, enhancing adaptability. Struts 2 also includes the ActionSupport class, which …
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Using a Containerized Nginx Proxy to Serve a Multi-Application .NET System
By Kevin Campusano
September 24, 2024
We recently blogged about how we deployed a system made of multiple .NET applications using Docker containers. In order to make them accessible over the internet, we created a reverse proxy using Nginx.
In that case, we installed and configured the Nginx instance directly in the server, as opposed to the rest of the applications, which ran within containers. That approach did and still does work well for us.
In this article, we’re going to explore an alternative strategy. One where we push the containerization aspect further and deploy and run the Nginx instance itself in a Docker container.
Reintroducing the demo project
Like I said, our system has multiple runtime components, each one of them running in their own container. We have two ASP.NET Core web applications: an Admin Portal and a Web API. They live in this Git repository. And we also have a Postgres database, which the apps interact with.
We also have another repository where the deployment-related files are stored. Among others, there are the expected compose.yaml and Dockerfiles that describe the entire infrastructure.
Throughout this post we will update those deployment configuration files to add an Nginx …
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