Docker

Install docker¶

ref: https://docs.docker.com/engine/install/ubuntu/#install-using-the-convenience-script

curl -fsSL https://get.docker.com -o get-docker.sh
sudo sh get-docker.sh
sudo usermod -aG docker rammus

docker-compose: https://docs.docker.com/compose/install/

sudo curl -L "https://github.com/docker/compose/releases/download/1.27.4/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
sudo chmod +x /usr/local/bin/docker-compose

Minimize docker image¶

Delete libraries only used in build time¶

apk update \
    && apk add --no-cache --virtual .build-deps curl \
    && curl -sL $TOOL_URL | gzip -d - > /usr/local/bin/new_tool \
    && chmod +x /usr/local/bin/new_tool \
    && apk del .build-deps

Clena docker legacy data¶

docker image prune -af
docker rmi $(docker images -f "dangling=true" -q) -f
docker volume rm $(docker volume ls -qf dangling=true)

Buildkit¶

Troubleshooting¶

{"registry-mirrors": ["https://mirror.gcr.io"]} cause error¶

不能和 registry-mirrors 一起用 (issue: https://github.com/moby/moby/issues/39120)

resolve image config for docker.io/docker/dockerfile:experimental:¶

DOCKER_BUILDKIT=1 docker build -t demo .

[+] Building 0.5s (3/3) FINISHED
 => [internal] load build definition from Dockerfile                                                                         0.0s
 => => transferring dockerfile: 259B                                                                                         0.0s
 => [internal] load .dockerignore                                                                                            0.0s
 => => transferring context: 2B                                                                                              0.0s
 => ERROR resolve image config for docker.io/docker/dockerfile:experimental                                                  0.5s
------
 > resolve image config for docker.io/docker/dockerfile:experimental:
------
failed to solve with frontend dockerfile.v0: failed to solve with frontend gateway.v0: docker.io/docker/dockerfile:experimental not found

Solution

在 ~/.docker/daemon.json 加入

"features": {
    "buildkit": true
}

或是

DOCKER_BUILDKIT=1

要在 Dockerfile 開頭加入 # syntax = docker/dockerfile:experimental

# syntax = docker/dockerfile:experimental
FROM alpine:3.10

failed to solve with frontend dockerfile.v0: failed to create LLB definition: Dockerfile parse error line 3: Unknown flag: mount

error: failed to get status: rpc error: code = Unavailable desc = connection error: desc = "transport: error while dialing: dial unix /run/buildkit/buildkitd.sock: connect: no such file or directory"¶

error: failed to get status: rpc error: code = Unavailable desc = connection error: desc = "transport: error while dialing: dial unix /run/buildkit/buildkitd.sock: connect: no such file or directory"

buildctl build \
  --frontend=dockerfile.v0 \
  --local context=echo-box/2.0 --local dockerfile=echo-box/2.0 \
  --output type=image,name=ghcr.io/swaglive/action-demo:2.0,push=true \
  --export-cache type=inline \
  --import-cache type=registry,ref=ghcr.io/swaglive/action-demo:2.0