rare – fast regex parser, extractor and realtime aggregator

rare is a command-line utility that aggregates and displays information parsed from text files using regex and a simple handlebars-like expressions. rare is a play on “more” and “less“, but can also stand for “realtime aggregated regular expressions”.

Quickly search, reformat and visualize text files such as logs, csv, json, etc.

It supports various CLI-based graphing and metric formats (filter (grep-like), histogram, table, bargraph, heatmap, reduce).

This is free and open source software.

Features include:

• Multiple summary formats including:
  • filter is grep-like, in that each line will be processed and the extracted key will be output directly to stdout.
  • histogram counts instances of the extracted key.
  • table counts the key in 2 dimensions.
  • heatmap displays a color-coded version of the strength of a cell in a dense format.
  • bargraph creates either a stacked or non-stacked bargraph based on 2 dimensions.
  • analyze uses the key as a numeric value and compute mean/median/mode/stddev/percentiles.
  • reduce allows evaluating data using expressions, and grouping/sorting the output.
• File glob expansions (e.g. /var/log/* or /var/log/*/*.log) and -R.
• Optional gzip decompression (with -z).
• Following -f or re-open following -F (use --poll to poll, and --tail to tail).
• Ignoring lines that match an expression (with -i).
• Aggregating and realtime summary (Don’t have to wait for all data to be scanned).
• Multi-threaded reading, parsing, and aggregation (It’s fast).
• Color-coded outputs (optionally).
• Pipe support (stdin for reading, stdout will disable realtime, and —csv formatting) e.g. tail -f | rare ... > out.

Website: github.com/zix99/rare
Support:
Developer: Chris LaPointe
License: GNU General Public License v3.0

rare is written in Go. Learn Go with our recommended free books and free tutorials.

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