ctop – top-like interface for monitoring Docker containers

ctop is a very simple, but very useful tool for when you run a number of Docker containers and want to have a top-like overview of their CPU, memory, and network usage.

This article provides more details on how to install, run, and use ctop effectively, including container filtering, single container view, etc.

k6 – API performance testing tool

k6 is a developer centric open source load and performance regression testing tool for testing the performance of your cloud native backend infrastructure: APIs, microservices, serverless, containers and websites. It’s built to integrate well into your development workflow and CI/CD automation pipelines.

This is one of the better tools that I’ve seen in a long time. Not only it does its job great, but it integrates brilliantly with your development and testing pipelines.

You can either build your tests from scratch, or you can convert import them from your existing tools. For example, Postman collections, environments, and tests can be converted to k6 with postman-to-k6. Here’s a blog post to get you started on that path.

Side note: if you hit the “EACCES: permission denied, mkdir ‘/usr/local/lib/node_modules/postman-to-k6/vendor’” durin the postman-to-k6 installation, then simply append “–unsafe-perm=true –allow-root” to the “npm install” command, as suggested in this GitHub thread.

k6 provides excellent functionality for extending your basic performance tests with additional checks, metrics, and thresholds. You can even keep using your existing Postman tests within k6.

There’s also a variety of output formats, ranging from CSV and JSON, all the way to InfluxDB with Grafana charts.

Install Postman on Fedora 31

Postman is a great tool for building and testing APIs. Unfortunately, however, it doesn’t come packaged as an RPM, so there’s some trickery involved in installing it on Fedora.

This blog post was very useful, with some minor corrections. Here’s what I had to do:

  • Download Postman from the site.
  • Move the archive to somewhere global: mv Postman-linux-x64-7.16.1.tar.gz /opt/
  • Extract the archive: tar xzvf Postman-linux-x64-7.16.1.tar.gz
  • Remove the archive: rm Postman-linux-x64-7.16.1.tar.gz
  • Check which directories are in the path: echo $PATH
  • Create a symbolic link in one of path directories: sudo ln -s /opt/Postman/Postman /usr/local/bin/postman
  • Create the desktop file: touch ~/.local/share/applications/postman.desktop
  • Edit the file with the content below.
[Desktop Entry]
Name=Postman
GenericName=API Client
X-GNOME-FullName=Postman API Client
Comment=Make and view REST API calls and responses
Keywords=api;
Exec=/usr/local/bin/postman
Terminal=false
Type=Application
Icon=/opt/Postman/app/resources/app/assets/icon.png
Categories=Development;Utilities;

Now you can run bitcoin casino Postman both via the command line (postman) and from the Gnome/Mate menu. You’ll find it under Applications->Programming.

PHP CodeSniffer: Ignoring rules

PHP CodeSniffer is a great tool for making sure all your code is consistent with a set of rules and guidelines. However, there are cases, when you need to ignore the rules for a particular code snippet. For example, when you are working with third-party frameworks or libraries.

CodeSniffer provides a number of ways to do this. Until today, the following worked well for me:

// @CodingStandardsIgnoreStart
echo "Here goes some code that breaks the rules";
// @CodingStandardsIgnoreEnd

This is particularly useful for code within functions and methods. But what if you need to ignore a particular rule for the whole file, especially in places like method names, which are difficult to surround by starting and ending annotation tags?

Here’s an example that worked for me (thanks to this comment for the solution):

<?php
/**
 * @phpcs:disable CakePHP.NamingConventions.ValidFunctionName.PublicWithUnderscore
 */

The only bit that you’d probably need now is an easy way to find the name of the rule from the CodeSniffer output. The usual output of “./vendor/bin/phpcs” looks like so:

FILE: src/Model/Table/KeysTable.php
-----------------------------------------------------------------------------------------------------
FOUND 1 ERROR AFFECTING 1 LINE
-----------------------------------------------------------------------------------------------------
 53 | ERROR | Public method name "KeysTable::_initializeSchema" must not be prefixed with underscore
-----------------------------------------------------------------------------------------------------

But if you run it with the “-s” flag (thanks to this comment), CodeSniffer will add sniff codes to all reports. Here’s the same example with “./vendor/bin/phpcs -s“:

FILE: src/Model/Table/KeysTable.php
------------------------------------------------------------------------------------------------------------------------------------------------------------------------
FOUND 1 ERROR AFFECTING 1 LINE
------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 53 | ERROR | Public method name "KeysTable::_initializeSchema" must not be prefixed with underscore
    |       | (CakePHP.NamingConventions.ValidFunctionName.PublicWithUnderscore)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------

And that’s the code sniff rule that you can add to the ignore annotation tag at the top of your file, like I’ve shown above.

Git tips: disable diff prefix

Pure gold.