代码拉取完成，页面将自动刷新
BuildKit is a toolkit for converting source code to build artifacts in an efficient, expressive and repeatable manner.
Key features:
Read the proposal from https://github.com/moby/moby/issues/32925
Introductory blog post https://blog.mobyproject.org/introducing-buildkit-17e056cc5317
Join #buildkit channel on Docker Community Slack
Note
If you are visiting this repo for the usage of BuildKit-only Dockerfile features like
RUN --mount=type=(bind|cache|tmpfs|secret|ssh), please refer to the Dockerfile reference.
Note
docker builduses Buildx and BuildKit by default since Docker Engine 23.0. You don't need to read this document unless you want to use the full-featured standalone version of BuildKit.
BuildKit is used by the following projects:
DOCKER_BUILDKIT=1 docker build)
For Kubernetes deployments, see examples/kubernetes.
BuildKit is composed of the buildkitd daemon and the buildctl client.
While the buildctl client is available for Linux, macOS, and Windows, the buildkitd daemon is only available for Linux and *Windows currently.
The latest binaries of BuildKit are available here for Linux, macOS, and Windows.
The buildkitd daemon requires the following components to be installed:
Starting the buildkitd daemon:
You need to run buildkitd as the root user on the host.
$ sudo buildkitd
To run buildkitd as a non-root user, see docs/rootless.md.
The buildkitd daemon supports two worker backends: OCI (runc) and containerd.
By default, the OCI (runc) worker is used. You can set --oci-worker=false --containerd-worker=true to use the containerd worker.
We are open to adding more backends.
To start the buildkitd daemon using systemd socket activation, you can install the buildkit systemd unit files. See Systemd socket activation
The buildkitd daemon listens gRPC API on /run/buildkit/buildkitd.sock by default, but you can also use TCP sockets.
See Expose BuildKit as a TCP service.
See instructions and notes at docs/windows.md.
Homebrew formula (unofficial) is available for macOS.
$ brew install buildkit
The Homebrew formula does not contain the daemon (buildkitd).
For example, Lima can be used for launching the daemon inside a Linux VM.
brew install lima
limactl start template://buildkit
export BUILDKIT_HOST="unix://$HOME/.lima/buildkit/sock/buildkitd.sock"
To build BuildKit from source, see .github/CONTRIBUTING.md.
For a buildctl reference, see this document.
BuildKit builds are based on a binary intermediate format called LLB that is used for defining the dependency graph for processes running part of your build. tl;dr: LLB is to Dockerfile what LLVM IR is to C.
See solver/pb/ops.proto for the format definition, and see ./examples/README.md for example LLB applications.
Currently, the following high-level languages have been implemented for LLB:
Frontends are components that run inside BuildKit and convert any build definition to LLB. There is a special frontend called gateway (gateway.v0) that allows using any image as a frontend.
During development, Dockerfile frontend (dockerfile.v0) is also part of the BuildKit repo. In the future, this will be moved out, and Dockerfiles can be built using an external image.
buildctl
buildctl build \
--frontend=dockerfile.v0 \
--local context=. \
--local dockerfile=.
# or
buildctl build \
--frontend=dockerfile.v0 \
--local context=. \
--local dockerfile=. \
--opt target=foo \
--opt build-arg:foo=bar
--local exposes local source files from client to the builder. context and dockerfile are the names Dockerfile frontend looks for build context and Dockerfile location.
If the Dockerfile has a different filename it can be specified with --opt filename=./Dockerfile-alternative.
External versions of the Dockerfile frontend are pushed to https://hub.docker.com/r/docker/dockerfile-upstream and https://hub.docker.com/r/docker/dockerfile and can be used with the gateway frontend. The source for the external frontend is currently located in ./frontend/dockerfile/cmd/dockerfile-frontend but will move out of this repository in the future (#163). For automatic build from master branch of this repository docker/dockerfile-upstream:master or docker/dockerfile-upstream:master-labs image can be used.
buildctl build \
--frontend gateway.v0 \
--opt source=docker/dockerfile \
--local context=. \
--local dockerfile=.
buildctl build \
--frontend gateway.v0 \
--opt source=docker/dockerfile \
--opt context=https://github.com/moby/moby.git \
--opt build-arg:APT_MIRROR=cdn-fastly.deb.debian.org
By default, the build result and intermediate cache will only remain internally in BuildKit. An output needs to be specified to retrieve the result.
buildctl build ... --output type=image,name=docker.io/username/image,push=true
To export the image to multiple registries:
buildctl build ... --output type=image,\"name=docker.io/username/image,docker.io/username2/image2\",push=true
To export the cache embed with the image and pushing them to registry together, type registry is required to import the cache, you should specify --export-cache type=inline and --import-cache type=registry,ref=.... To export the cache to a local directly, you should specify --export-cache type=local.
Details in Export cache.
buildctl build ...\
--output type=image,name=docker.io/username/image,push=true \
--export-cache type=inline \
--import-cache type=registry,ref=docker.io/username/image
Keys supported by image output:
name=<value>: specify image name(s)push=true: push after creating the imagepush-by-digest=true: push unnamed imageregistry.insecure=true: push to insecure HTTP registryoci-mediatypes=true: use OCI mediatypes in configuration JSON instead of Docker'sunpack=true: unpack image after creation (for use with containerd)dangling-name-prefix=<value>: name image with prefix@<digest>, used for anonymous imagesname-canonical=true: add additional canonical name name@<digest>
compression=<uncompressed|gzip|estargz|zstd>: choose compression type for layers newly created and cached, gzip is default value. estargz should be used with oci-mediatypes=true.compression-level=<value>: compression level for gzip, estargz (0-9) and zstd (0-22)rewrite-timestamp=true: rewrite the file timestamps to the SOURCE_DATE_EPOCH value.
See docs/build-repro.md for how to specify the SOURCE_DATE_EPOCH value.force-compression=true: forcefully apply compression option to all layers (including already existing layers)store=true: store the result images to the worker's (e.g. containerd) image store as well as ensures that the image has all blobs in the content store (default true). Ignored if the worker doesn't have image store (e.g. OCI worker).annotation.<key>=<value>: attach an annotation with the respective key and value to the built image
annotation-<type>.<key>=<value>, annotation[<platform>].<key>=<value> and both combined with annotation-<type>[<platform>].<key>=<value>, allows configuring exactly where to attach the annotation.<type> specifies what object to attach to, and can be any of manifest (the default), manifest-descriptor, index and index-descriptor
<platform> specifies which objects to attach to (by default, all), and is the same key passed into the platform opt, see docs/multi-platform.md.docs/annotations.md for more details.If credentials are required, buildctl will attempt to read Docker configuration file $DOCKER_CONFIG/config.json.
$DOCKER_CONFIG defaults to ~/.docker.
The local client will copy the files directly to the client. This is useful if BuildKit is being used for building something else than container images.
buildctl build ... --output type=local,dest=path/to/output-dir
To export specific files use multi-stage builds with a scratch stage and copy the needed files into that stage with COPY --from.
...
FROM scratch as testresult
COPY --from=builder /usr/src/app/testresult.xml .
...
buildctl build ... --opt target=testresult --output type=local,dest=path/to/output-dir
With a multi-platform build, a subfolder matching each target platform will be created in the destination directory:
FROM busybox AS build
ARG TARGETOS
ARG TARGETARCH
RUN mkdir /out && echo foo > /out/hello-$TARGETOS-$TARGETARCH
FROM scratch
COPY --from=build /out /
$ buildctl build \
--frontend dockerfile.v0 \
--opt platform=linux/amd64,linux/arm64 \
--output type=local,dest=./bin/release
$ tree ./bin
./bin/
└── release
├── linux_amd64
│ └── hello-linux-amd64
└── linux_arm64
└── hello-linux-arm64
You can set platform-split=false to merge files from all platforms together
into same directory:
$ buildctl build \
--frontend dockerfile.v0 \
--opt platform=linux/amd64,linux/arm64 \
--output type=local,dest=./bin/release,platform-split=false
$ tree ./bin
./bin/
└── release
├── hello-linux-amd64
└── hello-linux-arm64
Tar exporter is similar to local exporter but transfers the files through a tarball.
buildctl build ... --output type=tar,dest=out.tar
buildctl build ... --output type=tar > out.tar
# exported tarball is also compatible with OCI spec
buildctl build ... --output type=docker,name=myimage | docker load
buildctl build ... --output type=oci,dest=path/to/output.tar
buildctl build ... --output type=oci > output.tar
The containerd worker needs to be used
buildctl build ... --output type=image,name=docker.io/username/image
ctr --namespace=buildkit images ls
To change the containerd namespace, you need to change worker.containerd.namespace in /etc/buildkit/buildkitd.toml.
To show local build cache (/var/lib/buildkit):
buildctl du -v
To prune local build cache:
buildctl prune
BuildKit supports the following cache exporters:
inline: embed the cache into the image, and push them to the registry togetherregistry: push the image and the cache separatelylocal: export to a local directorygha: export to GitHub Actions cacheIn most case you want to use the inline cache exporter.
However, note that the inline cache exporter only supports min cache mode.
To enable max cache mode, push the image and the cache separately by using registry cache exporter.
inline and registry exporters both store the cache in the registry. For importing the cache, type=registry is sufficient for both, as specifying the cache format is not necessary.
buildctl build ... \
--output type=image,name=docker.io/username/image,push=true \
--export-cache type=inline \
--import-cache type=registry,ref=docker.io/username/image
Note that the inline cache is not imported unless --import-cache type=registry,ref=... is provided.
Inline cache embeds cache metadata into the image config. The layers in the image will be left untouched compared to the image with no cache information.
Docker-integrated BuildKit (DOCKER_BUILDKIT=1 docker build) and docker buildxrequires
--build-arg BUILDKIT_INLINE_CACHE=1 to be specified to enable the inline cache exporter.
However, the standalone buildctl does NOT require --opt build-arg:BUILDKIT_INLINE_CACHE=1 and the build-arg is simply ignored.
buildctl build ... \
--output type=image,name=localhost:5000/myrepo:image,push=true \
--export-cache type=registry,ref=localhost:5000/myrepo:buildcache \
--import-cache type=registry,ref=localhost:5000/myrepo:buildcache
--export-cache options:
type=registrymode=<min|max>: specify cache layers to export (default: min)
min: only export layers for the resulting imagemax: export all the layers of all intermediate stepsref=<ref>: specify repository reference to store cache, e.g. docker.io/user/image:tag
image-manifest=<true|false>: whether to export cache manifest as an OCI-compatible image manifest rather than a manifest list/index (default: false, must be used with oci-mediatypes=true)oci-mediatypes=<true|false>: whether to use OCI mediatypes in exported manifests (default: true, since BuildKit v0.8)compression=<uncompressed|gzip|estargz|zstd>: choose compression type for layers newly created and cached, gzip is default value. estargz and zstd should be used with oci-mediatypes=true
compression-level=<value>: choose compression level for gzip, estargz (0-9) and zstd (0-22)force-compression=true: forcibly apply compression option to all layersignore-error=<false|true>: specify if error is ignored in case cache export fails (default: false)--import-cache options:
type=registryref=<ref>: specify repository reference to retrieve cache from, e.g. docker.io/user/image:tag
buildctl build ... --export-cache type=local,dest=path/to/output-dir
buildctl build ... --import-cache type=local,src=path/to/input-dir
The directory layout conforms to OCI Image Spec v1.0.
--export-cache options:
type=localmode=<min|max>: specify cache layers to export (default: min)
min: only export layers for the resulting imagemax: export all the layers of all intermediate stepsdest=<path>: destination directory for cache exportertag=<tag>: specify custom tag of image to write to local index (default: latest)image-manifest=<true|false>: whether to export cache manifest as an OCI-compatible image manifest rather than a manifest list/index (default: false, must be used with oci-mediatypes=true)oci-mediatypes=<true|false>: whether to use OCI mediatypes in exported manifests (default true, since BuildKit v0.8)compression=<uncompressed|gzip|estargz|zstd>: choose compression type for layers newly created and cached, gzip is default value. estargz and zstd should be used with oci-mediatypes=true.compression-level=<value>: compression level for gzip, estargz (0-9) and zstd (0-22)force-compression=true: forcibly apply compression option to all layersignore-error=<false|true>: specify if error is ignored in case cache export fails (default: false)--import-cache options:
type=localsrc=<path>: source directory for cache importertag=<tag>: specify custom tag of image to read from local index (default: latest)digest=sha256:<sha256digest>: specify explicit digest of the manifest list to importbuildctl build ... \
--output type=image,name=docker.io/username/image,push=true \
--export-cache type=gha \
--import-cache type=gha
GitHub Actions cache saves both cache metadata and layers to GitHub's Cache service. This cache currently has a size limit of 10GB that is shared across different caches in the repo. If you exceed this limit, GitHub will save your cache but will begin evicting caches until the total size is less than 10 GB. Recycling caches too often can result in slower runtimes overall.
Similarly to using actions/cache, caches are scoped by branch, with the default and target branches being available to every branch.
Following attributes are required to authenticate against the GitHub Actions Cache service API:
url: Cache server URL (default $ACTIONS_CACHE_URL)token: Access token (default $ACTIONS_RUNTIME_TOKEN) This type of cache can be used with Docker Build Push Action
where url and token will be automatically set. To use this backend in an inline run step, you have to include crazy-max/ghaction-github-runtime
in your workflow to expose the runtime.
--export-cache options:
type=ghamode=<min|max>: specify cache layers to export (default: min)
min: only export layers for the resulting imagemax: export all the layers of all intermediate stepsscope=<scope>: which scope cache object belongs to (default buildkit)ignore-error=<false|true>: specify if error is ignored in case cache export fails (default: false)timeout=<duration>: sets the timeout duration for cache export (default: 10m)--import-cache options:
type=ghascope=<scope>: which scope cache object belongs to (default buildkit)timeout=<duration>: sets the timeout duration for cache import (default: 10m)buildctl build ... \
--output type=image,name=docker.io/username/image,push=true \
--export-cache type=s3,region=eu-west-1,bucket=my_bucket,name=my_image \
--import-cache type=s3,region=eu-west-1,bucket=my_bucket,name=my_image
The following attributes are required:
bucket: AWS S3 bucket (default: $AWS_BUCKET)region: AWS region (default: $AWS_REGION)Storage locations:
s3://<bucket>/<prefix><blobs_prefix>/<sha256>, default: s3://<bucket>/blobs/<sha256>
s3://<bucket>/<prefix><manifests_prefix>/<name>, default: s3://<bucket>/manifests/<name>
S3 configuration:
blobs_prefix: global prefix to store / read blobs on s3 (default: blobs/)manifests_prefix: global prefix to store / read manifests on s3 (default: manifests/)endpoint_url: specify a specific S3 endpoint (default: empty)use_path_style: if set to true, put the bucket name in the URL instead of in the hostname (default: false)AWS Authentication:
The simplest way is to use an IAM Instance profile. Other options are:
access_key_id: Access Key IDsecret_access_key: Secret Access Keysession_token: Session Token--export-cache options:
type=s3mode=<min|max>: specify cache layers to export (default: min)
min: only export layers for the resulting imagemax: export all the layers of all intermediate stepsprefix=<prefix>: set global prefix to store / read files on s3 (default: empty)name=<manifest>: specify name of the manifest to use (default buildkit)
;. The standard use case is to use the git sha1 as name, and the branch name as duplicate, and load both with 2 import-cache commands.ignore-error=<false|true>: specify if error is ignored in case cache export fails (default: false)--import-cache options:
type=s3prefix=<prefix>: set global prefix to store / read files on s3 (default: empty)blobs_prefix=<prefix>: set global prefix to store / read blobs on s3 (default: blobs/)manifests_prefix=<prefix>: set global prefix to store / read manifests on s3 (default: manifests/)name=<manifest>: name of the manifest to use (default buildkit)buildctl build ... \
--output type=image,name=docker.io/username/image,push=true \
--export-cache type=azblob,account_url=https://myaccount.blob.core.windows.net,name=my_image \
--import-cache type=azblob,account_url=https://myaccount.blob.core.windows.net,name=my_image
The following attributes are required:
account_url: The Azure Blob Storage account URL (default: $BUILDKIT_AZURE_STORAGE_ACCOUNT_URL)Storage locations:
<account_url>/<container>/<prefix><blobs_prefix>/<sha256>, default: <account_url>/<container>/blobs/<sha256>
<account_url>/<container>/<prefix><manifests_prefix>/<name>, default: <account_url>/<container>/manifests/<name>
Azure Blob Storage configuration:
container: The Azure Blob Storage container name (default: buildkit-cache or $BUILDKIT_AZURE_STORAGE_CONTAINER if set)blobs_prefix: Global prefix to store / read blobs on the Azure Blob Storage container (<container>) (default: blobs/)manifests_prefix: Global prefix to store / read blobs on the Azure Blob Storage container (<container>) (default: manifests/)Azure Blob Storage authentication:
There are 2 options supported for Azure Blob Storage authentication:
secret_access_key attribute to specify the primary or secondary account key for your Azure Blob Storage account. Azure Blob Storage account keys
Note
Account name can also be specified with
account_nameattribute (or$BUILDKIT_AZURE_STORAGE_ACCOUNT_NAME) if it is not part of the account URL host.
--export-cache options:
type=azblobmode=<min|max>: specify cache layers to export (default: min)
min: only export layers for the resulting imagemax: export all the layers of all intermediate stepsprefix=<prefix>: set global prefix to store / read files on the Azure Blob Storage container (<container>) (default: empty)name=<manifest>: specify name of the manifest to use (default: buildkit)
;. The standard use case is to use the git sha1 as name, and the branch name as duplicate, and load both with 2 import-cache commands.ignore-error=<false|true>: specify if error is ignored in case cache export fails (default: false)--import-cache options:
type=azblobprefix=<prefix>: set global prefix to store / read files on the Azure Blob Storage container (<container>) (default: empty)blobs_prefix=<prefix>: set global prefix to store / read blobs on the Azure Blob Storage container (<container>) (default: blobs/)manifests_prefix=<prefix>: set global prefix to store / read manifests on the Azure Blob Storage container (<container>) (default: manifests/)name=<manifest>: name of the manifest to use (default: buildkit)If you have multiple BuildKit daemon instances, but you don't want to use registry for sharing cache across the cluster, consider client-side load balancing using consistent hashing.
See ./examples/kubernetes/consistenthash.
To output build metadata such as the image digest, pass the --metadata-file flag.
The metadata will be written as a JSON object to the specified file.
The directory of the specified file must already exist and be writable.
buildctl build ... --metadata-file metadata.json
jq '.' metadata.json
{
"containerimage.config.digest": "sha256:2937f66a9722f7f4a2df583de2f8cb97fc9196059a410e7f00072fc918930e66",
"containerimage.descriptor": {
"annotations": {
"config.digest": "sha256:2937f66a9722f7f4a2df583de2f8cb97fc9196059a410e7f00072fc918930e66",
"org.opencontainers.image.created": "2022-02-08T21:28:03Z"
},
"digest": "sha256:19ffeab6f8bc9293ac2c3fdf94ebe28396254c993aea0b5a542cfb02e0883fa3",
"mediaType": "application/vnd.oci.image.manifest.v1+json",
"size": 506
},
"containerimage.digest": "sha256:19ffeab6f8bc9293ac2c3fdf94ebe28396254c993aea0b5a542cfb02e0883fa3"
}
On Systemd based systems, you can communicate with the daemon via Systemd socket activation, use buildkitd --addr fd://.
You can find examples of using Systemd socket activation with BuildKit and Systemd in ./examples/systemd.
The buildkitd daemon can listen the gRPC API on a TCP socket.
It is highly recommended to create TLS certificates for both the daemon and the client (mTLS).
Enabling TCP without mTLS is dangerous because the executor containers (aka Dockerfile RUN containers) can call BuildKit API as well.
buildkitd \
--addr tcp://0.0.0.0:1234 \
--tlscacert /path/to/ca.pem \
--tlscert /path/to/cert.pem \
--tlskey /path/to/key.pem
buildctl \
--addr tcp://example.com:1234 \
--tlscacert /path/to/ca.pem \
--tlscert /path/to/clientcert.pem \
--tlskey /path/to/clientkey.pem \
build ...
buildctl build can be called against randomly load balanced buildkitd daemons.
See also Consistent hashing for client-side load balancing.
BuildKit can also be used by running the buildkitd daemon inside a Docker container and accessing it remotely.
We provide the container images as moby/buildkit:
moby/buildkit:latest: built from the latest regular release
moby/buildkit:rootless: same as latest but runs as an unprivileged user, see docs/rootless.md
moby/buildkit:master: built from the master branchmoby/buildkit:master-rootless: same as master but runs as an unprivileged user, see docs/rootless.md
To run daemon in a container:
docker run -d --name buildkitd --privileged moby/buildkit:latest
export BUILDKIT_HOST=docker-container://buildkitd
buildctl build --help
To connect to a BuildKit daemon running in a Podman container, use podman-container:// instead of docker-container:// .
podman run -d --name buildkitd --privileged moby/buildkit:latest
buildctl --addr=podman-container://buildkitd build --frontend dockerfile.v0 --local context=. --local dockerfile=. --output type=oci | podman load foo
sudo is not required.
To connect to a BuildKit daemon running in a Nerdctl container, use nerdctl-container:// instead of docker-container://.
nerdctl run -d --name buildkitd --privileged moby/buildkit:latest
buildctl --addr=nerdctl-container://buildkitd build --frontend dockerfile.v0 --local context=. --local dockerfile=. --output type=oci | nerdctl load
sudo is not required.
For Kubernetes deployments, see examples/kubernetes.
To run the client and an ephemeral daemon in a single container ("daemonless mode"):
docker run \
-it \
--rm \
--privileged \
-v /path/to/dir:/tmp/work \
--entrypoint buildctl-daemonless.sh \
moby/buildkit:master \
build \
--frontend dockerfile.v0 \
--local context=/tmp/work \
--local dockerfile=/tmp/work
or
docker run \
-it \
--rm \
--security-opt seccomp=unconfined \
--security-opt apparmor=unconfined \
-e BUILDKITD_FLAGS=--oci-worker-no-process-sandbox \
-v /path/to/dir:/tmp/work \
--entrypoint buildctl-daemonless.sh \
moby/buildkit:master-rootless \
build \
--frontend \
dockerfile.v0 \
--local context=/tmp/work \
--local dockerfile=/tmp/work
BuildKit supports OpenTelemetry for buildkitd gRPC
API and buildctl commands. To capture the trace to
Jaeger, set JAEGER_TRACE
environment variable to the collection address.
docker run -d -p6831:6831/udp -p16686:16686 jaegertracing/all-in-one:latest
export JAEGER_TRACE=0.0.0.0:6831
# restart buildkitd and buildctl so they know JAEGER_TRACE
# any buildctl command should be traced to http://127.0.0.1:16686/
Please refer to docs/rootless.md.
Please refer to docs/multi-platform.md.
buildctl
buildctl has support for modifying the colors that are used to output information to the terminal. You can set the environment variable BUILDKIT_COLORS to something like run=green:warning=yellow:error=red:cancel=255,165,0 to set the colors that you would like to use. Setting NO_COLOR to anything will disable any colorized output as recommended by no-color.org.
Parsing errors will be reported but ignored. This will result in default color values being used where needed.
You can change how many log lines are visible for active steps in tty mode by setting BUILDKIT_TTY_LOG_LINES to a number (default: 6).
Want to contribute to BuildKit? Awesome! You can find information about contributing to this project in the CONTRIBUTING.md
此处可能存在不合适展示的内容，页面不予展示。您可通过相关编辑功能自查并修改。
如您确认内容无涉及 不当用语 / 纯广告导流 / 暴力 / 低俗色情 / 侵权 / 盗版 / 虚假 / 无价值内容或违法国家有关法律法规的内容，可点击提交进行申诉，我们将尽快为您处理。