LazyStern - Kubernetes Logs Helper

Description

This is a Bash function designed to provide a simpler interface for querying logs from a Kubernetes cluster. The function is a wrapper around stern. I recommend learning stern instead of using this function. As this is a poorly implemented wrapper around stern for the lazy.

Please note this is simple helper and not fully featured.

It is designed to be a quick way to get logs from a Kubernetes cluster with an interactive interface. The interactive interface will fetch contexts and namespaces from which the user can select before running & will guide user through creating a time range from which to fetch logs.

The function will automatically detect the context namespace and kubernetes context if they are not provided. If you wish to query logs from a single pod. Please use kubectl logs instead.

Logs will be outputted as raw and can be piped into other commands like awk, jq or yq for further processing.

Usage

Usage: lazystern [OPTIONS]
Options:
 -h, --help      Display this help message
 -i, --interactive  Enable interactive mode
 -s, --since     Display logs since the specified time (passed to stern)
	 Default: 48h, Format: [<num>m, <num>h] days, weeks, months & years are not valid
 -t, --to         Display logs until the specified time (used to filter logs with awk)
	 Format: ISO 8601, e.g. 2021-08-01T00:00:00.000Z
 -n, --namespace  Specify the kubernetes namespace to fetch logs from
 -c, --context    Specify the kubernetes context to fetch logs from
 -f, --follow     Follow logs

ISO Helper

Wrapper around GNU date (coreutil)

# ISO Helper
# -d Option accepts
#  Modifiers relative to now in order to build ISO datetime
#   See GNU date coreutil relative items docs for syntax.
#   https://www.gnu.org/software/coreutils/manual/html_node/Relative-items-in-date-strings.html

#   Example: 
#   +1 day -4 hour -2 weeks +2 minutes +1 second
iso -d "-2 days"

Please Note

Stern does not allow for collecting logs in a time window. Instead will get logs since a time. In order to This function will fetch all logs from the provided since time and then use awk to filter logs past the provided TO datetime.

Examples

# with named options and full name
lazystern --namespace your-namespace --context your-context --since 1h --to $(iso -d "-30 minutes");
# using alias and short options for the lazy
lstern -n <namespace> -c <context> -s <stern since option> -t <DateTime ISO>;

# Run the interactive mode
lstern -i;
lstern --interactive;

# show pretty error logs
lstern -s 10m | grep 'error' | jq '.';

# show pretty logs from interactive mode
lstern -i | jq '.'

Getting Started

Dependencies

This function requires the following dependencies to be installed:

• kubectl
• stern
• awk
• jq

Installing

To install the function:

• download it and add it to your .bashrc, .bash_profile, .zshrc or .zsh_profile file.

# Clone the repository
git clone --depth 1 https://github.com/NickMoignard/lazy-stern.git ~/.lazy-stern
# Source the file in your shell profile
# If you use zsh use .zshrc instead of .bashrc
echo "source ~/.lazy-stern/lazy-stern.sh" >> ~/.bashrc

Linux

This function makes use of gdate instead of date. If you are using linux please create a symlink to gdate as date.

sudo ln -s $(which date) /bin/gdate

Contributing

Thank you for considering contributing to LazyStern! To contribute, please follow these guidelines:

1. Fork the repository and create a new branch.
2. Make your changes and test them thoroughly.
3. Commit your changes with a descriptive commit message.
4. Push your changes to your fork and submit a pull request.

Please ensure your code adheres to the existing code style and conventions.

Issues

If you encounter any issues with LazyStern, please feel free to open an issue on GitHub. I welcome bug reports, feature requests, and general feedback.

License

LazyStern is open source software licensed under the MIT License. See the LICENSE file for more information.