how get and use a docker container id from part of its name in a terminal pipe request? - linux

Question

I am trying to combine the following commands:
docker ps | grep track
that will give me
6b86b28a27b0 dev/jobservice/worker-jobtracking:3.5.0-SNAPSHOT "/tini -- /startup/s…" 25 seconds ago Up 2 seconds (health: starting)
jobservice_jobTrackingWorker_1
So then, I grab the id and use it in the next request as:
docker logs 6b8 | grep -A 3 'info'
So far, the easiest way I could find was to send those commands separately, but i wonder if there would be a simple way to do it.
I think that the main issue here is that I am trying to find the name of the container based on part of its name.
So, to resume, I would like to find and store the id of a container based on its name then use it to explore its logs.
Thanks!

Answer 1

Perhaps there are cleaner ways to do it, but this works.
To get the ID of a partially matching container name:
$ docker ps --format "{{.ID}} {{.Names}}" | grep "partial" | cut -d " " -f1
Then you can use it in another bash command:
$ docker logs $(docker ps --format "{{.ID}} {{.Names}}" | grep "partial" | cut -d " " -f1)
Or wrap it in a function:
$ function dlog() { docker logs $(docker ps --format "{{.ID}} {{.Names}}" | grep "$1" | cut -d " " -f1); }
Which can then be used as:
$ dlog partial

Answer 2

In a nutshell the pure bash approach to achieve what you want:
With sudo:
sudo docker ps | grep -i track - | awk '{print $1}' | head -1 | xargs sudo docker logs
Without sudo:
docker ps | grep -i track - | awk '{print $1}' | head -1 | xargs docker logs
Now let's break it down...
Let's see what containers I have running in my laptop for the Elixir programming language:
command:
sudo docker ps | grep -i elixir -
output:
0a19c6e305a2 exadra37/phoenix-dev:1.5.3_elixir-1.10.3_erlang-23.0.2_git "iex -S mix phx.serv…" 7 days ago Up 7 days 127.0.0.1:2000-2001->2000-2001/tcp Projects_todo-tasks_app
65ef527065a8 exadra37/st3-3211-elixir:latest "bash" 7 days ago Up 7 days SUBL3_1600981599
232d8cfe04d5 exadra37/phoenix-dev:1.5.3_elixir-1.10.3_erlang-23.0.2_git "mix phx.server" 8 days ago Up 8 days 127.0.0.1:4000-4001->4000-4001/tcp Staging_todo-tasks_app
Now let's find their ids:
command:
sudo docker ps | grep -i elixir - | awk '{print $1}'
output:
0a19c6e305a2
65ef527065a8
232d8cfe04d5
Let's get the first container ID:
command:
sudo docker ps | grep -i elixir - | awk '{print $1}' | head -1
NOTE: replace head -1 with head -2 to get the second line in the output...
output:
0a19c6e305a2
Let's see the logs for the first container in the list
command:
sudo docker ps | grep -i elixir - | awk '{print $1}' | head -1 | xargs sudo docker logs
NOTE: replace head -1 with tail -1 to get the logs for the last container in the list.
output:
[info] | module=WebIt.Live.Calendar.Socket function=mount/1 line=14 | Mount Calendar for date: 2020-09-30 23:29:38.229174Z
[debug] | module=Tzdata.ReleaseUpdater function=poll_for_update/0 line=40 | Tzdata polling for update.
[debug] | module=Tzdata.ReleaseUpdater function=poll_for_update/0 line=44 | Tzdata polling shows the loaded tz database is up to date.

Answer 3

Combining the different replies, I used:
function dlog() { docker ps | grep -i track - | awk '{print $1}' | head -1 | xargs docker logs | grep -i -A 4 "$2";}
to get the best of both worlds. So I can have a function that will have me type 4 letters instead of 2 commands and with no case sensitivity
I can then use dlog keyword to get my logs.
I hardcoded track and -A 4 as I usually use that query but I could have passed them as arguments to add on modularity (my goal here was really simplicity)
Thanks for your help!