Docker Image Prune Using --filter on Repository Name And Other Info

Preface

Hello there!

I've done some googling and I have not seen any clear documentation or discussion about this aspect of the docker image prune command.

I've read a fair amount of the documentation here:

• https://docs.docker.com/edge/engine/reference/commandline/system_prune/
• https://docs.docker.com/engine/reference/commandline/image_prune/
• Stack Overflow
• etc.

Problem

There appears to be no mechanism for filtering on information specific to the image name and/or tags.

User Story

I have a build process that builds intermediate images for my process. In addition to that I'm also pulling in other images from a docker registry, and this machine may be dirty from the build system using other build processes docker images.

Because of this I would like to be able to filter out images/tags that are irrelevant and/or relevant to my images.

For example, my docker images after the process is run, looks like so:

REPOSITORY                              TAG                  IMAGE ID            CREATED             SIZE
example.com/releng/api-db               latest               f19d60cab35c        6 days ago          281MB
example.com/releng/worker               latest               7fe81bdeb5d2        6 days ago          921MB
example.com/releng/api                  latest               5152cade7311        6 days ago          921MB
example.com/example_product/api         latest-development   de17f92e5504        7 days ago          333MB
rabbitmq                                3-management         046c07b70859        7 days ago          124MB
dinkel/clamavd                          latest               9a42e4755eb9        7 days ago          361MB
example.com/example_product/worker      latest-development   f57aab6d0d61        8 days ago          378MB
example.com/example_product/standalone  latest               8ac468f8a86f        2 weeks ago         2.25GB
example.com/example_product/halifax     latest-development   b7cbf1bda847        3 weeks ago         475MB
example.com/postgres                    9.4                  68c55c797542        5 weeks ago         263MB
ubuntu                                  latest               ccc7a11d65b1        2 months ago        120MB
redis                                   3.0.7                c44fa74ead88        3 months ago        91.6MB
nginx                                   1.12.0               313ec0a602bc        3 months ago        107MB
example.com/example_product/postgres    latest-development   4eb1ac130d39        6 months ago        265MB
python                                  2.7.12               0900c636e10d        10 months ago       676MB

Hypothetical Solution

What would be super convenient is the ability to filter based on the image name, the repo that houses the images, and/or the ability to filter by tags as well within that context.

Let's pretend I want to remove all images retrieved from the example.com repo.

Remove images based on repo fuzzy matching

docker image prune --force --filter "repository=example.com*"

Or maybe I want it based on image name

Remove images based on image name fuzzy matching

docker image prune --force --filter "repository=*example_product*"

Questions

Am I misunderstanding the --filter flag?

I realize grep'ing is a solution, but this seems like the tool itself would benefit more from creating this feature rather than relying on work arounds from within the environment's tooling?

I look forward to your feedback 😄

Output of docker version:

Client:
 Version:      17.09.0-ce
 API version:  1.32
 Go version:   go1.8.3
 Git commit:   afdb6d4
 Built:        Tue Sep 26 22:40:09 2017
 OS/Arch:      darwin/amd64

Server:
 Version:      17.09.0-ce
 API version:  1.32 (minimum version 1.12)
 Go version:   go1.8.3
 Git commit:   afdb6d4
 Built:        Tue Sep 26 22:45:38 2017
 OS/Arch:      linux/amd64
 Experimental: true

Output of docker info:

Containers: 8
 Running: 0
 Paused: 0
 Stopped: 8
Images: 48
Server Version: 17.09.0-ce
Storage Driver: aufs
 Root Dir: /var/lib/docker/aufs
 Backing Filesystem: extfs
 Dirs: 140
 Dirperm1 Supported: true
Logging Driver: json-file
Cgroup Driver: cgroupfs
Plugins:
 Volume: local
 Network: bridge host ipvlan macvlan null overlay
 Log: awslogs fluentd gcplogs gelf journald json-file logentries splunk syslog
Swarm: inactive
Runtimes: runc
Default Runtime: runc
Init Binary: docker-init
containerd version: 06b9cb35161009dcb7123345749fef02f7cea8e0
runc version: 3f2f8b84a77f73d38244dd690525642a72156c64
init version: 949e6fa
Security Options:
 seccomp
  Profile: default
Kernel Version: 4.9.49-moby
Operating System: Alpine Linux v3.5
OSType: linux
Architecture: x86_64
CPUs: 4
Total Memory: 1.952GiB
Name: moby
ID: TERQ:LFYT:CWRT:4ZPB:37GA:BEWW:265O:6Q35:6DCW:6ISX:OMI2:2EQ7
Docker Root Dir: /var/lib/docker
Debug Mode (client): false
Debug Mode (server): true
 File Descriptors: 19
 Goroutines: 31
 System Time: 2017-10-18T00:08:35.693503549Z
 EventsListeners: 1
No Proxy: *.local, 169.254/16
Registry: https://index.docker.io/v1/
Experimental: true
Insecure Registries:
 127.0.0.0/8
Live Restore Enabled: false

Additional environment details (AWS, VirtualBox, physical, etc.):
OSX

Start with the referenced Docker image prune and system prune documentation, then inspect the current docker image prune --filter behavior and its handling of repository and tag information. Clarify the matching semantics and safety expectations from the issue and comment discussion; done requires an agreed feature scope and corresponding CLI behavior.