Add post about docker commands

content/post/2025-06-18-docker-shell-tricks/index.md

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+---
+title: "Docker Shell Tricks"
+date: 2025-06-18T09:10:13-04:00
+categories:
+  - Tips and Tricks
+tags: 
+  - Docker
+  - CI/CD
+  - Linux
+  - Containers
+  - DevOps
+---
+
+# Overview
+
+One of my all time favorite tricks when working with Docker. Getting information on or performing an action on multiple containers with similar naming schemes.
+
+Passing the --filter name= flag allows for fuzzy matching.
+
+docker container ps -q returns only container ids by default and is perfect for combining with commands like docker container stop or docker container rm.
+
+Of course if you are using docker compose, simply running `docker compose down` will accomplish the same thing.
+
+I wanted to share one of my all time favorite tricks when working with Docker.  It is fairly common (for me at least) to want to perform some action on a number of containers at once.  For example, sometimes I have a lot of random containers running and I want to shut them all down (and sometimes remove them) at once.  Of course if you are using compose you can simply run `docker compose down` but sometimes you have containers not managed by a compose file.
+
+In the past I would write shell scripts to handle this.  Something like:
+
+```bash
+$ for i in $(docker container ps --format '{{.ID}}'); do docker container rm --force $i; done
+5d5b3004003f
+038b809fb0af
+de4abb80414c
+530440f8848e
+3aff02eddfe1
+3e29e7db168c
+46275b44f744
+b3cd33cd7658
+8e9f226f107e
+29f67eea6ac8
+597b72330d3d
+
+```
+
+This works ok, but if you also only want to kill certain containers it gets a bit trickier.  For instance, we use Docker to spin up preview environments where each environment may have up to 10 containers.  They are all prefixed with a PR number so I could do something like this:
+
+```bash
+$ for i in $(docker container ps --format '{{.ID}} {{.Names}}' | grep pr1 | awk '{print $1}'); do docker container rm --force $i; done
+```
+
+While both of those solutions work, they are a bit messing and fortunately Docker has a much better solution built in.  Passing the `-q` flag to certain commands will by default just return a list of ids
+
+```bash
+$ docker container ps                                                         
+CONTAINER ID   IMAGE     COMMAND                  CREATED         STATUS         PORTS     NAMES
+31c3dbd33795   nginx     "/docker-entrypoint.…"   6 minutes ago   Up 6 minutes   80/tcp    pr9
+899384beaf6f   nginx     "/docker-entrypoint.…"   6 minutes ago   Up 6 minutes   80/tcp    pr8
+e3aa660916d7   nginx     "/docker-entrypoint.…"   6 minutes ago   Up 6 minutes   80/tcp    pr7
+5fd2998a800a   nginx     "/docker-entrypoint.…"   6 minutes ago   Up 6 minutes   80/tcp    pr6
+898450246c0c   nginx     "/docker-entrypoint.…"   6 minutes ago   Up 6 minutes   80/tcp    pr5
+9e22f39b9810   nginx     "/docker-entrypoint.…"   6 minutes ago   Up 6 minutes   80/tcp    pr4
+3a0ee53664cf   nginx     "/docker-entrypoint.…"   6 minutes ago   Up 6 minutes   80/tcp    pr3
+7e3a512739a4   nginx     "/docker-entrypoint.…"   6 minutes ago   Up 6 minutes   80/tcp    pr2
+af96f09686ef   nginx     "/docker-entrypoint.…"   6 minutes ago   Up 6 minutes   80/tcp    pr1
+
+$ docker container ps -q                                                      
+31c3dbd33795
+899384beaf6f
+e3aa660916d7
+5fd2998a800a
+898450246c0c
+9e22f39b9810
+3a0ee53664cf
+7e3a512739a4
+af96f09686ef
+
+```
+
+One of the best parts about this trick though is that you can combine it with the `--filter` flag like this:
+
+```bash
+$ docker container ps --filter name=pr -q                                        
+31c3dbd33795
+899384beaf6f
+e3aa660916d7
+5fd2998a800a
+898450246c0c
+9e22f39b9810
+3a0ee53664cf
+7e3a512739a4
+af96f09686ef
+```
+
+Now stopping all my containers is as easy as:
+
+```bash
+$ docker container rm $(docker container ps -qa) --force
+31c3dbd33795
+899384beaf6f
+e3aa660916d7
+5fd2998a800a
+898450246c0c
+9e22f39b9810
+3a0ee53664cf
+7e3a512739a4
+af96f09686ef
+```
+Or, if I just want to stop specific containers, say all the ones that start with pr11217 in the name:
+```bash
+$ docker container rm $(docker container ps --filter name=pr11217 -qa) --force
+```
+Pretty slick!  No more messing with `awk,grep,head,tail, etc` , instead just do it in one simple command.  I would love to hear your tips and tricks for working with Docker!
+
+#docker #cicd #containers #softwaredevelopment