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Transforming TCP Sockets to HTTP With Go

Sometimes, we need to work with legacy applications, and legacy applications can be hard to rewrite and change. Imagine, for example, we have an application that is using raw TCP sockets to communicate with another process. Raw TCP sockets are fast, but they have various problems. For example, all data is sent in plain text over the network and without authentication (if we don’t implement a protocol).

One solution is to use HTTPS connections instead. We can also authenticate those requests with an Authentication Bearer. For example, I’ve created a simple HTTP server with Python and Flask:

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Deploying a Django Application to AWS EC2 Instance With Docker

In AWS, we have several ways to deploy Django (and not Django applications) with Docker. We can use ECS or EKS clusters. If we don't have one ECS or Kubernetes cluster up and running, maybe it can be complex. Today, I want to show how deploy a Django application in production mode within a EC2 host. Let's start.

The idea is create one EC2 instance (one simple Amazon Linux AMI AWS-supported image). This host doesn't initially have Docker installed. We need to install it. When we launch one instance, when we're configuring the instance, we can specify user data to configure an instance or run a configuration script during launch.

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Playing With TOTP (2FA) and Mobile Applications With Ionic

Today I want to play with Two Factor Authentication. When we speak about 2FA, TOTP comes to mind. There are many TOTP clients (e.g. Google Authenticator).

My idea with this prototype is to build one mobile application (with Ionic) and validate one TOTP token in a server (in this case a Python/Flask application). The token will be generated with a standard TOTP client. Let’s start

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Tutorial on Data Analysis With Python and Pivot Tables With Pandas

One of the first posts on my blog was about Pivot tables. I’d created a library to pivot tables in my PHP scripts. The library is not very beautiful (it throws a lot of warnings), but it works. These days I’m playing with Python Data Analysis and I’m using Pandas. The purpose of this post is something that I like a lot: learn by doing. So I want to do the same operations that I did eight years ago in the post but now with Pandas. Let’s start.

I’ll start with the same data source that I used almost ten years ago. One simple set of records, with clicks and number of users

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Using Cache Buster With OpenUI5 Outside SCP

When we work with SPAs and web applications we need to handle with the browser’s cache. Sometimes we change our static files but the client’s browser uses a cached version of the file instead of the new one. We can tell the user: please empty your cache to use the new version. But most of the times the user doesn’t know what we’re talking about, and we have a problem. There’s a technique called cache buster used to bypass this issue. It consists of a change to the name of the file (or adding an extra parameter), basically to ensure that the browser will send a different request to the server to prevent the browser from reusing the cached version of the file.

When we work with sapui5 application over SCP, we only need to use the cachebuster version of sap-ui-core