🔴 prepend numbers, stats, dates, durations to streams
foo@bar:~$ prefix -h
USAGE
prefix [flags] file
FLAGS
-format string
format string (default "{{DEFAULT}} ")
SYNTAX
{{.Duration | short_duration}} {{.Duration}} displayed in a pretty & short format (len<=7)
{{.Duration}} time since previous line was started
{{.Format}} the value you set with -format
{{.LineNumber3}} alias for {{printf "%-3d" .LineNumber}}
{{.LineNumber4}} alias for {{printf "%-4d" .LineNumber}}
{{.LineNumber5}} alias for {{printf "%-5d" .LineNumber}}
{{.LineNumber}} display line number
{{.ShortDuration}} alias for {{.Duration | short_duration}}
{{.ShortUptime}} alias for {{.Uptime | short_duration}}
{{.Uptime | short_duration}} {{.Uptime}} displayed in a pretty & short format (len<=7)
{{.Uptime}} time since the the prefixer was initialized
{{env "USER"}} replace with content of the $USER env var
{{now | unixEpoch}} current timestamp
{{now}} current date (format: 2006-01-02 15:04:05.999999999 -0700 MST)
{{uuidv4}} UUID of the v4 (randomly generated) type
the following helpers are also available:
- from the text/template library https://golang.org/pkg/text/template/
- from the sprig project https://github.com/masterminds/sprig#usage
PRESETS
{{DEFAULT}} {{.LineNumber3}} up={{.ShortUptime}} d={{.ShortDuration}} |
{{SHORT_DATE}} {{now | date "06/02/01 15:04:05"}}
{{SLOW_LINES}} {{if (gt .Duration 1000000000)}}SLOW{{else}} {{end}} {{.Duration | short_duration}}
EXAMPLES
prefix apache.log
prefix -format=">>>" apache.log
tail -f apache.log | prefix -
my-cool-program 2>&1 | prefix -format="#{{.LineNumber5}} " -foo@bar:~$ generate-fake-data | prefix -format="#{{.LineNumber3}} {{.ShortUptime}} {{.ShortDuration}} | "
#1 73.6µs 80.9µs | At illum ut est sit soluta nulla numquam.
#2 112ms 111.9ms | Sunt quaerat ea dolores facere deleniti culpa numquam.
#3 327.1ms 215.1ms | Distinctio maxime consequatur est qui corporis sunt officia.
#4 605.3ms 278.2ms | Et quia odit molestias voluptas porro repellendus magnam.
#5 897.7ms 292.3ms | Corporis eos rem non hic esse optio quisquam.
#6 1.1s 211.7ms | Natus earum molestias iste architecto porro et blanditiis.
#7 1.3s 238.2ms | Eum repellendus nostrum qui eius suscipit fugit quia.
#8 1.4s 50.6ms | Et nesciunt quod fuga ut vel pariatur libero.
#9 1.6s 209.6ms | Rerum omnis soluta facilis voluptatem possimus et voluptas.
#10 1.9s 274.7ms | Possimus harum voluptatibus aperiam voluptatibus qui autem quam.foo@bar:~$ generate-fake-data | prefix -format="{{.LineNumber3}} "
1 At illum ut est sit soluta nulla numquam.
2 Nobis sunt quaerat ea dolores facere deleniti culpa.
3 Numquam ut distinctio maxime consequatur est qui corporis.
4 Sunt officia odit et quia odit molestias voluptas.
5 Porro repellendus magnam ipsa corporis eos rem non.
6 Hic esse optio quisquam hic natus earum molestias.
7 Iste architecto porro et blanditiis iste eum repellendus.
8 Nostrum qui eius suscipit fugit quia quo et.
9 Nesciunt quod fuga ut vel pariatur libero sequi.
10 Rerum omnis soluta facilis voluptatem possimus et voluptas.foo@bar:~$ generate-fake-data | prefix -format=">>> "
>>> At illum ut est sit soluta nulla numquam.
>>> Nobis sunt quaerat ea dolores facere deleniti culpa.
>>> Numquam ut distinctio maxime consequatur est qui corporis.
>>> Sunt officia odit et quia odit molestias voluptas.
>>> Porro repellendus magnam ipsa corporis eos rem non.
>>> Hic esse optio quisquam hic natus earum molestias.
>>> Iste architecto porro et blanditiis iste eum repellendus.
>>> Nostrum qui eius suscipit fugit quia quo et.
>>> Nesciunt quod fuga ut vel pariatur libero sequi.
>>> Rerum omnis soluta facilis voluptatem possimus et voluptas.foo@bar:~$ generate-fake-data | prefix -format="{{SLOW_LINES}} up={{.ShortUptime}} | "
876.7µs up=892.6µs | Rerum natus quo quo explicabo tempore et delectus.
SLOW 1s up=1.1s | Dolor blanditiis voluptas dolorum sint laudantium eveniet amet.
SLOW 1.3s up=2.4s | Qui asperiores molestiae est quia est eum omnis.
SLOW 1.3s up=3.6s | Illum explicabo aut illum iste pariatur aut laudantium.
982.2ms up=4.6s | Quibusdam asperiores consequatur est dolores quas dolor ipsam.
185.5ms up=4.8s | Possimus qui non rem qui cum sit temporibus.
167.5ms up=5s | Ea debitis sit deleniti cum ut adipisci in.
520.3ms up=5.5s | Eveniet molestias voluptatem voluptatem deserunt nisi tempora iusto.
215ms up=5.7s | Fugiat minus quam eos voluptatem labore sit velit.
SLOW 1s up=6.7s | Enim aut autem tenetur fugit minima quo atque.foo@bar:~$ generate-fake-data | prefix -format="{{SHORT_DATE}} "
20/19/09 00:02:43 At illum ut est sit soluta nulla numquam.
20/19/09 00:02:44 Sunt quaerat ea dolores facere deleniti culpa numquam.
20/19/09 00:02:45 Distinctio maxime consequatur est qui corporis sunt officia.
20/19/09 00:02:46 Et quia odit molestias voluptas porro repellendus magnam.
20/19/09 00:02:48 Corporis eos rem non hic esse optio quisquam.
20/19/09 00:02:49 Natus earum molestias iste architecto porro et blanditiis.
20/19/09 00:02:50 Eum repellendus nostrum qui eius suscipit fugit quia.
20/19/09 00:02:50 Et nesciunt quod fuga ut vel pariatur libero.
20/19/09 00:02:51 Rerum omnis soluta facilis voluptatem possimus et voluptas.
20/19/09 00:02:53 Possimus harum voluptatibus aperiam voluptatibus qui autem quam.$ go get -u moul.io/prefixSee https://github.com/moul/prefix/releases
I really welcome contributions. Your input is the most precious material. I'm well aware of that and I thank you in advance. Everyone is encouraged to look at what they can do on their own scale; no effort is too small.
Everything on contribution is sum up here: CONTRIBUTING.md
Thanks goes to these wonderful people (emoji key):
 Manfred Touron 🚧 📖 |
 moul-bot 🚧 |
This project follows the all-contributors specification. Contributions of any kind welcome!
© 2020-2021 Manfred Touron
Licensed under the Apache License, Version 2.0 (LICENSE-APACHE) or the MIT license (LICENSE-MIT), at your option. See the COPYRIGHT file for more details.
SPDX-License-Identifier: (Apache-2.0 OR MIT)
