Tutorials
Step-by-step technical guides on Docker, Linux, Python, Go, and more.
Page 18 of 36
How to find the mime type of a file in Python?
Here are some example on how to guess the mime type of a file using python. The first example uses the filename only and the second example opens the file to guess the mime type.
PostgreSQL: Update query for JSONB columns with examples
PostgreSQL 9.5 added the type JSONB, which supports json as datatype. Here we show an example on how to perform an UPDATE on a jsonb type using postgresql. If you want to override the whole dict, just send the json between single quotes. check here...
Move LUKS Encrypted Disk to Smaller SSD
In this tutorial, we are going to move a linux encrypted disk to a new one. In particular, we are going to move from an old hard drive to a brand new SSD (but smaller). This tutorial also works for moving encryted disk to a bigger disk.
Flask API POST Request: Handle JSON Data [Complete Tutorial]
Learn how to handle POST requests in Flask API. Complete tutorial with JSON data handling, validation, error handling, and testing with curl and Postman.
How to use setup Epson L355 on Ubuntu 18.04
Steps to install Epson L355 on Ubuntu 18.04. You will need to download the official drivers from epson.net (deb file). Use dpkg to install epson-inkjet-printer-201207w_1.0.0-1lsb3.2_amd64.deb. Finally, use the wizard as always. Check here for full details and epson Ubuntu 18.04 drivers.
How to update the Go version
Steps to update go lang to the latest version. Remove your current go and then Go to the [downloads](https://golang.org/dl/) page and download the binary release. finally install it following the steps in this guide.
Using python SQLAlchemy with SQLlite3 tutorial
Learn here how to use SQLIte3 with SQLAlchemy step by step. First, we are going to define some models and then we will see how to connect and make some queries. We are going to learn about the Unit of Work pattern, which is a very important concept on sqlalchemy.
SQLAlchemy Bulk Insert 2026: The Fastest Methods Compared (40x to 240x Speedup)
SQLAlchemy bulk insert performance guide 2026. ORM add_all vs bulk_save_objects vs Core execute_many (40x) vs PostgreSQL COPY via psycopg2 (240x). Real benchmarks with 100K rows. Async support included.
Gitlab CI register runner on multiple proyects
With gitlab ci if you want to reuse the runner on multiple projects you will need to be master an both proyects. You will need then to Go to Settings>CI/CD>Runner Settings of Project A and finally Edit the desired runner properties. Uncheck the "Lock to current projects" box. Check here for full detailed steps.
Bluetooth headset playing low quality on ubuntu 18
If you are using ubuntu and you bluetooth speaks is playing with low quality, check here for the solution. You need to edit the file /etc/bluetooth/audio.conf and change some configurations. Read here for more details.