👨🏿 👨🏻‍🎓 🗼 在没有Docker的情况下构建容器 🧢 🏇🏾 🏻

哈Ha 我们现在听到很多有关Kubernetis和Docker的信息。可能只有懒惰的人不了解它们。但是还有其他使用容器的选项。这是一位决定探索类似工具的发烧友的文章翻译。

我想谈谈如何在不使用Docker的情况下创建容器。我将使用OpenFaaS，它将OCI容器映像用于我的工作负载。我们可以说OpenFaaS是Kubernetes的CaaS平台，它能够运行微服务并免费添加FaaS和事件管理工具。我们将首先向您展示如何使用Docker CLI的内置buildkit，然后描述独立的buildkit （仅限Linux），然后介绍Google容器构建器Kaniko。

Docker怎么了？

是的，一切都和他在一起。它在armhf，arm64和x86_64上运行良好。Docker命令行的主要界面已不仅仅是构建/推送/运行，它还具有Docker Swarm和EE功能。

Docker替代品

已经进行了几次尝试，将Docker带回到我们都爱上的熟悉外观。

Docker - Docker本身现在使用容器来运行容器，并支持buildkit构建来创建高效的缓存构建。
Podman和buildah的结合是RedHat / IBM的创意，它们使用自己的OSS工具集来生成OCI图像。推销Podman时没有守护程序或root，但最终必须挂载覆盖文件系统并使用UNIX套接字。
邮袋-阿里巴巴提供的工具被认为是“高效企业级容器引擎”。它使用与Docker相同的容器化方式，并通过runc和“轻量级虚拟机”（如runV）支持容器级隔离。还更加强调图像分布和隔离。
BuildKit -buildkit Docker Inc . buildkit , , . (fork) , .
img — buildkit. . 2018 , . , img buildctr, buildkit, , img x86_64 armhf/arm64.
k3c — Rancher, containerd buildkit , Docker. ARM.

k3c, , , containerd buildkit.

, «build» , :

buildkit Docker
buildkit
Kaniko

( ) , OpenFaaS CLI « »,

HTTP Golang middleware, , , OpenFaaS.

faas-cli template store pull golang-middleware

faas-cli new --lang golang-middleware \
  build-test --prefix=alexellis2

--lang

build-test —

--prefix Docker Hub, OCI.

./
├── build-test
│   └── handler.go
└── build-test.yml

1 directory, 2 files

, . Go.

package function

import (
	"fmt"
	"io/ioutil"
	"net/http"
)

func Handle(w http.ResponseWriter, r *http.Request) {
	var input []byte

	if r.Body != nil {
		defer r.Body.Close()

		body, _ := ioutil.ReadAll(r.Body)

		input = body
	}

	w.WriteHeader(http.StatusOK)
	w.Write([]byte(fmt.Sprintf("Hello world, input was: %s", string(input))))
}

faas-cli build -f build-test.yml

Dockerfile

./template/golang-middleware/Dockerfile

FROM openfaas/of-watchdog:0.7.3 as watchdog
FROM golang:1.13-alpine3.11 as build
FROM alpine:3.12

. , . faas-cli push -f build-test.yml.

Buildkit Docker

, .

DOCKER_BUILDKIT=1 faas-cli build -f build-test.yml

Docker buildkit. Buildkit :

, — , " " , "sdk" .
buildkit , FROM () .

buildkit , FROM () .

FROM openfaas/of-watchdog:0.7.3 as watchdog
FROM golang:1.13-alpine3.11 as build
FROM alpine:3.11

Mac, buildkit Docker, .

Buildkit

Buildkit buildkit Linux, Mac.

faas-cli build docker, — . , , , :

faas-cli build -f build-test.yml --shrinkwrap

[0] > Building build-test.
Clearing temporary build folder: ./build/build-test/
Preparing ./build-test/ ./build/build-test//function
Building: alexellis2/build-test:latest with golang-middleware template. Please wait..
build-test shrink-wrapped to ./build/build-test/
[0] < Building build-test done in 0.00s.
[0] Worker done.

Total build time: 0.00

./build/build-test/ Dockerfile.

./build/build-test/
├── Dockerfile
├── function
│   └── handler.go
├── go.mod
├── main.go
└── template.yml

1 directory, 5 files

buildkit.

curl -sSLf https://github.com/moby/buildkit/releases/download/v0.6.3/buildkit-v0.6.3.linux-amd64.tar.gz | sudo tar -xz -C /usr/local/bin/ --strip-components=1

, buildkit, armhf arm64, .

buildkit :

sudo buildkitd 
WARN[0000] using host network as the default            
INFO[0000] found worker "l1ltft74h0ek1718gitwghjxy", labels=map[org.mobyproject.buildkit.worker.executor:oci org.mobyproject.buildkit.worker.hostname:nuc org.mobyproject.buildkit.worker.snapshotter:overlayfs], platforms=[linux/amd64 linux/386] 
WARN[0000] skipping containerd worker, as "/run/containerd/containerd.sock" does not exist 
INFO[0000] found 1 workers, default="l1ltft74h0ek1718gitwghjxy" 
WARN[0000] currently, only the default worker can be used. 
INFO[0000] running server on /run/buildkit/buildkitd.sock

, . buildctl. buildctl — , , , , , tar, .

buildctl build --help
NAME:
   buildctl build - build

USAGE:
   
  To build and push an image using Dockerfile:
    $ buildctl build --frontend dockerfile.v0 --opt target=foo --opt build-arg:foo=bar --local context=. --local dockerfile=. --output type=image,name=docker.io/username/image,push=true
  

OPTIONS:
   --output value, -o value  Define exports for build result, e.g. --output type=image,name=docker.io/username/image,push=true
   --progress value          Set type of progress (auto, plain, tty). Use plain to show container output (default: "auto")
   --trace value             Path to trace file. Defaults to no tracing.
   --local value             Allow build access to the local directory
   --frontend value          Define frontend used for build
   --opt value               Define custom options for frontend, e.g. --opt target=foo --opt build-arg:foo=bar
   --no-cache                Disable cache for all the vertices
   --export-cache value      Export build cache, e.g. --export-cache type=registry,ref=example.com/foo/bar, or --export-cache type=local,dest=path/to/dir
   --import-cache value      Import build cache, e.g. --import-cache type=registry,ref=example.com/foo/bar, or --import-cache type=local,src=path/to/dir
   --secret value            Secret value exposed to the build. Format id=secretname,src=filepath
   --allow value             Allow extra privileged entitlement, e.g. network.host, security.insecure
   --ssh value               Allow forwarding SSH agent to the builder. Format default|<id>[=<socket>|<key>[,<key>]]

, Docker DOCKER_BUILDKIT :

sudo -E buildctl build --frontend dockerfile.v0 \
 --local context=./build/build-test/ \
 --local dockerfile=./build/build-test/ \
 --output type=image,name=docker.io/alexellis2/build-test:latest,push=true

docker login $HOME/.docker/config.json` .

ASCII .

img buildkit

img , , .

, , , . armhf ARM64 .

x86_64 v0.5.7 7 2019, Go 1.11, 1.13 Go :

sudo curl -fSL "https://github.com/genuinetools/img/releases/download/v0.5.7/img-linux-amd64" -o "/usr/local/bin/img" \
	&& sudo chmod a+x "/usr/local/bin/img"

buildctl:

img build --help
Usage: img build [OPTIONS] PATH

Build an image from a Dockerfile.

Flags:

  -b, --backend  backend for snapshots ([auto native overlayfs]) (default: auto)
  --build-arg    Set build-time variables (default: [])
  -d, --debug    enable debug logging (default: false)
  -f, --file     Name of the Dockerfile (Default is 'PATH/Dockerfile') (default: <none>)
  --label        Set metadata for an image (default: [])
  --no-cache     Do not use cache when building the image (default: false)
  --no-console   Use non-console progress UI (default: false)
  --platform     Set platforms for which the image should be built (default: [])
  -s, --state    directory to hold the global state (default: /home/alex/.local/share/img)
  -t, --tag      Name and optionally a tag in the 'name:tag' format (default: [])
  --target       Set the target build stage to build (default: <none>)

sudo img build -f ./build/build-test/Dockerfile -t alexellis2/build-test:latest ./build/build-test/

img . , root-.

fatal error: unexpected signal during runtime execution
[signal SIGSEGV: segmentation violation code=0x1 addr=0xe5 pc=0x7f84d067c420]

runtime stack:
runtime.throw(0xfa127f, 0x2a)
	/home/travis/.gimme/versions/go1.11.10.linux.amd64/src/runtime/panic.go:608 +0x72
runtime.sigpanic()
	/home/travis/.gimme/versions/go1.11.10.linux.amd64/src/runtime/signal_unix.go:374 +0x2f2

goroutine 529 [syscall]:
runtime.cgocall(0xc9d980, 0xc00072d7d8, 0x29)
	/home/travis/.gimme/versions/go1.11.10.linux.amd64/src/runtime/cgocall.go:128 +0x5e fp=0xc00072d7a0 sp=0xc00072d768 pc=0x4039ee
os/user._Cfunc_mygetgrgid_r(0x2a, 0xc000232260, 0x7f84a40008c0, 0x400, 0xc0004ba198, 0xc000000000)

Kaniko

Kaniko — Google, . .

docker run -v $PWD/build/build-test:/workspace \
 -v ~/.docker/config.json:/kaniko/config.json \
 --env DOCKER_CONFIG=/kaniko \
 gcr.io/kaniko-project/executor:latest \
 -d alexellis2/build-test:latest

–d , .
-v Kaniko, config.json .

Kaniko , , Kaniko one-shot , , Buildkit.

— . Docker , . , . , Docker, , IP-.
buildkit. . DOCKER_BUILDKIT=1
buildkit. , Docker, CI box runner. Linux, MacOS. , TCP?

. faasd, containerd CNI, Docker Kubernetes.

Kaniko. , Kaniko, - Docker, .

OpenFaaS faas-cli build –shrinkwrap . OpenFaaS:

OpenFaaS CI/CD shrinkwrap buildkit. Docker Docker buildkit.

faasd containerd docker, buildkit.

我们没有涉及工作流的重要部分之一-部署。只要符合无服务器工作负载的定义，任何OCI容器都可以部署在Kubernetes之上的OpenFaaS控制平面中。

在没有Docker的情况下构建容器

Docker怎么了？

Buildkit Docker

Buildkit

img buildkit

Kaniko

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