'docker context ls' or 'docker context inspect' slow responses with remote servers

• This is a bug report
• This is a feature request
• I searched existing issues before opening this one

Expected behavior

Return current used docker context faster

Actual behavior

while using a remote docker host context through a VPN or over the internet, the listing and inspecting of the contexts is very slow

$ time docker context ls
NAME                DESCRIPTION                               DOCKER ENDPOINT                 KUBERNETES ENDPOINT   ORCHESTRATOR
bb-dev *            BB Dev Environment                        ssh://deploy@192.168.213.214                         swarm
default             Current DOCKER_HOST based configuration   unix:///var/run/docker.sock                           swarm

real	0m2.547s
user	0m0.020s
sys	0m0.015s

If using the default (local) docker context , everything seems to be ok

$ docker context use default
Current context is now "default"
$ time docker context ls
NAME                DESCRIPTION                               DOCKER ENDPOINT                 KUBERNETES ENDPOINT   ORCHESTRATOR
bb-dev              BB Dev Environment                        ssh://deploy@192.168.213.214                         swarm
default *           Current DOCKER_HOST based configuration   unix:///var/run/docker.sock                           swarm

real	0m0.026s
user	0m0.024s
sys	0m0.010s

Steps to reproduce the behavior

Output of docker version:

lient: Docker Engine - Community
 Version:           19.03.11
 API version:       1.40
 Go version:        go1.13.10
 Git commit:        42e35e61f3
 Built:             Mon Jun  1 09:12:34 2020
 OS/Arch:           linux/amd64
 Experimental:      false

Server: Docker Engine - Community
 Engine:
  Version:          19.03.11
  API version:      1.40 (minimum version 1.12)
  Go version:       go1.13.10
  Git commit:       42e35e61f3
  Built:            Mon Jun  1 09:11:07 2020
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          1.2.13
  GitCommit:        7ad184331fa3e55e52b890ea95e65ba581ae3429
 runc:
  Version:          1.0.0-rc10
  GitCommit:        dc9208a3303feef5b3839f4323d9beb36df0a9dd
 docker-init:
  Version:          0.18.0
  GitCommit:        fec3683

Output of docker info:

Client:
 Debug Mode: false

Server:
 Containers: 1
  Running: 0
  Paused: 0
  Stopped: 1
 Images: 37
 Server Version: 19.03.11
 Storage Driver: overlay2
  Backing Filesystem: extfs
  Supports d_type: true
  Native Overlay Diff: 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 local logentries splunk syslog
 Swarm: inactive
 Runtimes: runc
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: 7ad184331fa3e55e52b890ea95e65ba581ae3429
 runc version: dc9208a3303feef5b3839f4323d9beb36df0a9dd
 init version: fec3683
 Security Options:
  apparmor
  seccomp
   Profile: default
 Kernel Version: 5.4.0-37-generic
 Operating System: Ubuntu 20.04 LTS
 OSType: linux
 Architecture: x86_64
 CPUs: 12
 Total Memory: 15.56GiB
 Name: aduzsardi-nix
 ID: V6CN:HNWD:PENV:MYG3:2ORG:SYRC:P6LD:HJNM:P3GS:OZ3K:7VTR:6QWV
 Docker Root Dir: /var/lib/docker
 Debug Mode: false
 Registry: https://index.docker.io/v1/
 Labels:
 Experimental: false
 Insecure Registries:
  gitlab.bigbrother.lokaal:5005
  127.0.0.0/8
 Live Restore Enabled: false

WARNING: No swap limit support

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

I'm connecting to remote docker or docker swarm hosts trough VPNs from home to office network

I want to set my bash prompt to show the docker context currently in use so i know where i am at all times , but the time it takes to return my prompt every time i press the return key on the keyboard takes about ~3s of so it's not usable

The script i was using

$ cat /etc/profile.d/docker_prompt.sh

#!/bin/bash

_get_docker_ctx()
{
    # Get current context
    if type docker &>/dev/null; then
        CONTEXT=$(docker context ls | grep -F '*' | awk '{ print $1}')
    fi
}

__docker_ps1()
{
    _get_docker_ctx
    if [ -n "$CONTEXT" ]; then
        echo "[dctx: ${CONTEXT}] - "
    fi
}

__colored_docker_ps1()
{
    _get_docker_ctx
    if [ -n "$CONTEXT" ]; then
        echo -e "\e[1m\e[37m[\e[92mdctx: \e[36m${CONTEXT}\e[37m] - \e[0m"
    fi

}

And PS1 prompt

export PS1='$(__colored_docker_ps1)\[\e]0;\u@\h: \w\a\]${debian_chroot:+($debian_chroot)}\u@\h:\w\$'

Proposal

It would be nice if we could read the currently used context from a file or config , so every time you run docker context use ... the config would be updated with the "current-context: something" like kubectl does

Start by reproducing docker context ls and docker context inspect with a remote SSH context over a VPN, then compare them with the default local context. Read the context-use and context-list command paths and configuration handling; done means remote context queries no longer delay the prompt and the current context can be obtained without contacting the remote server.