Better Docker logs with Python

A Python script that formats docker logs output with colors, scrolling, and search.

You pipe it like this:

docker logs -f --timestamps my-container 2>&1 | dlogs-fmt

Each line is color-coded by log level (red for errors, yellow for warnings, green for info). HTTP requests are parsed and colored by their status code (e.g., GET 200 /path). To keep the output clean, consecutive lines from the same Python module are grouped under a single header.

If you pass --timestamps to Docker, the script strips the ISO date prefix and keeps only HH:MM:SS. When you scroll back you see the original log time, not your terminal’s current time.

Keys

Key	Action
s / S	Scroll up / down one line
d / D	Scroll up / down one page
↑ ↓	Scroll one line
Shift+↑ Shift+↓	Scroll one page
e / E	Previous / next error
w / W	Previous / next warning
/	Regex search
← →	Previous / next search match
a	Resume live tailing

Scrolling pauses live output automatically. Error/warning navigation jumps through the full log, not a filtered view, so you keep the surrounding context.

How it works

The status bar stays pinned at the bottom using VT100 scroll regions (rows 1 through N-1 scroll, row N stays fixed). Keyboard input comes from /dev/tty in raw mode since stdin is the pipe. A background thread fills a ring buffer (10k lines by default) so the UI doesn’t block, and only visible lines get formatted on each redraw.

Get it

Single file, no dependencies, Python 3.8+.

Add this to your ~/.bashrc or ~/.zshrc:

dlogs() {
  local container="${1:-my-container}"
  shift 2>/dev/null
  docker logs -f --timestamps "$container" 2>&1 | python3 -u ~/.local/bin/dlogs-fmt "$@"
}