Kev’s Blog – Page 11 – Kev's Development Toolbox

August 7, 2024August 7, 2024

Which my.cnf is mysql using?

mysql searches for your local my.cnf in a number of default places, so finding which is actually in use can be an issue.

To find which search paths are currently being used by your current mysql install (from here), use:

mysql --help | grep my.cnf

And it will show a list of paths like this:

> mysql --help | grep my.cnf
                      order of preference, my.cnf, $MYSQL_TCP_PORT,
/etc/my.cnf /etc/mysql/my.cnf /opt/homebrew/etc/my.cnf ~/.my.cnf

Note that if you installed mysql via homebrew (on MacOS), this will also show the homebrew path where my.cnf is located.

July 7, 2024July 6, 2024

AWS Lightsail default ssh userid

To ssh into AWS ec2 instances the default user id is usually ‘ec2-user’ (see my ec2 ssh checklist here).

Lightsail vps instances appear to use different default userids, depending on the OS. For example, for an Ubuntu Lightsail instance the default ssh userid is ‘ubuntu’:

ssh -i path-to-your-ssh-pen-file ubuntu@your-instance-ip

July 6, 2024September 13, 2024

Filtering JSON data in Python

Given typical JSON of car models like this:

json_data = """{
  "cars": [
    {
      "manufacturer": "ford",
      "model": "mondeo"
    },
    {
      "manufacturer": "vauxhall",
      "model": "corsa"
    }
  ]
}"""

To filter matching cars by manufacturer in Python, use:

result = [car for car in json_data['cars'] if(car['manufacturer'] == "ford")]

Discussed in answers here.

July 6, 2024July 6, 2024

Documenting functions in Python

To document individual functions in Python, use a docstring like this:

def example_function():
"""Performs xyz
More details here
"""

Discussed in answers here.