docker ps: allow formatting as JSON
With this patch:
docker ps --format 'table {{.Names}}\t{{.Platform}}'
NAMES PLATFORM
optimistic_nightingale linux/arm64
mycontainer linux/arm64/v8
trusting_goldstine linux/arm64
docker ps --format '{{.Platform}}'
linux/arm64
linux/arm64/v8
linux/arm64
docker ps --format '{{json .Platform}}'
{"architecture":"arm64","os":"linux"}
{"architecture":"arm64","os":"linux","variant":"v8"}
{"architecture":"arm64","os":"linux"}
docker ps --format 'json'
{"Command":"\"/bin/bash\"","CreatedAt":"2025-05-13 10:12:19 +0000 UTC","ID":"e8b3b2d604f1","Image":"docker-cli-dev","Labels":"desktop.docker.io/binds/0/Source=/Users/thajeztah/go/src/github.com/docker/cli,desktop.docker.io/binds/0/SourceKind=hostFile,desktop.docker.io/binds/0/Target=/go/src/github.com/docker/cli,desktop.docker.io/mounts/0/Source=/var/run/docker.sock,desktop.docker.io/mounts/0/SourceKind=dockerSocketProxied,desktop.docker.io/mounts/0/Target=/var/run/docker.sock,desktop.docker.io/ports.scheme=v2","LocalVolumes":"1","Mounts":"/host_mnt/User…,docker-cli-dev…,/run/host-serv…","Names":"optimistic_nightingale","Networks":"bridge","Platform":{"architecture":"arm64","os":"linux"},"Ports":"","RunningFor":"38 minutes ago","Size":"0B","State":"running","Status":"Up 38 minutes"}
{"Command":"\"/docker-entrypoint.…\"","CreatedAt":"2025-05-13 09:58:01 +0000 UTC","ID":"c93b808dd54e","Image":"nginx:alpine","Labels":"desktop.docker.io/ports.scheme=v2,maintainer=NGINX Docker Maintainers \u003cdocker-maint@nginx.com\u003e","LocalVolumes":"0","Mounts":"","Names":"mycontainer","Networks":"bridge","Platform":{"architecture":"arm64","os":"linux","variant":"v8"},"Ports":"80/tcp","RunningFor":"53 minutes ago","Size":"0B","State":"running","Status":"Up 53 minutes"}
{"Command":"\"/usr/bin/gotty --ti…\"","CreatedAt":"2025-05-13 07:31:18 +0000 UTC","ID":"cbb981b06e46","Image":"thajeztah/dockershell:latest","Labels":"desktop.docker.io/ports.scheme=v2,com.thajeztah.docker-shell=1","LocalVolumes":"0","Mounts":"","Names":"trusting_goldstine","Networks":"bridge","Platform":{"architecture":"arm64","os":"linux"},"Ports":"0.0.0.0:55000-\u003e8080/tcp","RunningFor":"3 hours ago","Size":"0B","State":"running","Status":"Up 3 hours"}
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>