mzgb 0.2.0

Fast CLI for filtering very large log files by level, pattern, and time range

mzgb

mzgb (mezgeb — "record" in Amharic) is a fast CLI tool for filtering and navigating very large log files. Streams line by line — no memory issues, no matter the file size.

Filter by log level, regex pattern, or time range. Invert matches, pipe structured JSON/CSV output, scan multiple files at once, and decompress .gz/.bz2 on the fly. Works with plaintext, JSON, and logfmt. Pipes cleanly with kubectl, journalctl, cat, jq, and friends.

Install

# pip
pip install mzgb

# pipx (isolated, recommended)
pipx install mzgb

# Homebrew (macOS)
brew tap mukesudo/mzgb && brew install mzgb

# Scoop (Windows)
scoop bucket add mzgb https://github.com/mukesudo/scoop-mzgb
scoop install mzgb

# Snap (Linux)
snap install mzgb --classic

# Nix
nix run github:mukesudo/mzgb

Or from source:

git clone https://github.com/mukesudo/mzgb.git
cd mzgb
python3 -m mzgb --help

Usage

# Filter by log level
mzgb --level ERROR app.log

# Pattern search with context lines
mzgb --pattern "timeout" -C 2 app.log

# Filter by time range
mzgb --from "2024-01-15 14:00" --to "2024-01-15 15:00" app.log

# Invert — everything EXCEPT DEBUG
mzgb --invert --level DEBUG app.log

# Show line numbers
mzgb -n --level ERROR app.log

# Multiple files / globs
mzgb --level ERROR service-a.log service-b.log
mzgb --level ERROR /var/log/*.log

# Structured output — pipe into jq or pandas
mzgb --output json --level ERROR app.log | jq '.msg'
mzgb --output csv app.log > report.csv

# Compressed logs — .gz and .bz2
mzgb --level ERROR archive.log.gz
mzgb --level ERROR archive.log.bz2

# Pipe from anywhere
kubectl logs pod/api | mzgb --level ERROR
journalctl | mzgb --summary

# Follow live logs
mzgb --follow --level ERROR app.log

Options

Flag	Short	Description
--level	-l	Filter by log level (ERROR, WARN, INFO). Repeatable.
--pattern	-p	Filter by keyword or regex.
--from / --to		Time range filter.
--context	-C	Show N lines before and after each match.
--invert	-v	Print lines that do not match.
--line-numbers	-n	Prefix output with source line number.
--no-color		Disable ANSI color output.
--output	-o	Output format: text (default), json, csv.
--summary	-s	Print a summary table instead of raw lines.
--follow	-f	Follow file for new lines (like tail -f).

Development

# Run tests
python -m pytest

# Run with coverage
python -m pytest --cov=mzgb

License

MIT — see LICENSE