Awesome
Docker Buildkite Plugin
A Buildkite plugin for running pipeline steps in Docker containers.
Also see the Docker Compose Buildkite Plugin which supports building images, docker-compose.yml
, multiple containers, and overriding many of Docker’s defaults.
Example
run
The following pipeline will build a binary in the dist directory using golang Docker image and then uploaded as an artifact.
steps:
- command: "go build -o dist/my-app ."
artifact_paths: "./dist/my-app"
plugins:
- docker#v5.12.0:
image: "golang:1.11"
Windows images are also supported:
steps:
- command: "dotnet publish -c Release -o published"
plugins:
- docker#v5.12.0:
image: "microsoft/dotnet:latest"
always-pull: true
:warning: Warning: you should be careful when using an array or multi-line string as the command at the step level with this plugin. You will need to ensure that each line finishes with ;
, execute a script in your repository or use the plugin's command
option instead. You will also have to take into account the image's entrypoint and shell
option.
If you want to control how your command is passed to the docker container, you can use the command
parameter on the plugin directly:
steps:
- plugins:
- docker#v5.12.0:
image: "mesosphere/aws-cli"
always-pull: true
command: ["s3", "sync", "s3://my-bucket/dist/", "/app/dist"]
artifact_paths: "dist/**"
You can pass in additional environment variables and customize what is mounted into the container.
Note: If you are utilizing Buildkite's Elastic CI Stack S3 Secrets plugin, you must specify the environment variable key names as they appear in your S3 bucket's environment
hook in order to access the secret from within your container.
steps:
- command: "yarn install; yarn run test"
plugins:
- docker#v5.12.0:
image: "node:7"
always-pull: true
environment:
- "MY_SECRET_KEY"
- "MY_SPECIAL_BUT_PUBLIC_VALUE=kittens"
Environment variables available in the step can also automatically be propagated to the container:
Note: this will not automatically propagate Elastic CI Stack S3 Secrets plugin environment
variables. Refer above for explicitly importing values from that plugin.
steps:
- command: "yarn install; yarn run test"
env:
MY_SPECIAL_BUT_PUBLIC_VALUE: kittens
plugins:
- docker#v5.12.0:
image: "node:7"
always-pull: true
propagate-environment: true
AWS authentication tokens can be automatically propagated to the container, for example from an assume role plugin or ECS IAM role:
steps:
- command: "yarn install; yarn run test"
env:
MY_SPECIAL_BUT_PUBLIC_VALUE: kittens
plugins:
- docker#v5.12.0:
image: "node:7"
always-pull: true
propagate-aws-auth-tokens: true
You can pass in additional volumes to be mounted. This is useful for running Docker:
steps:
- command: "docker build . -t image:tag; docker push image:tag"
plugins:
- docker#v5.12.0:
image: "docker:latest"
always-pull: true
volumes:
- "/var/run/docker.sock:/var/run/docker.sock"
You can disable the default behaviour of mounting in the checkout to workdir
:
steps:
- command: "npm start"
plugins:
- docker#v5.12.0:
image: "node:7"
always-pull: true
mount-checkout: false
Variable interpolation can be tricky due to the 3 layers involved (Buildkite, agent VM, and docker). For example, if you want to use ECR Buildkite plugin, you will need to use the following syntax. Note the $$
prefix for variables that would otherwise resolve at pipeline upload time, not runtime:
steps:
- command: "yarn install; yarn run test"
plugins:
- ecr#v2.7.0:
login: true
account_ids:
- "d"
- "p"
region: us-west-2
no-include-email: true
- docker#v5.12.0:
image: "d.dkr.ecr.us-west-2.amazonaws.com/imagename"
command: ["./run-integration-tests.sh"]
expand-volume-vars: true
volumes:
- "/var/run/docker.sock:/var/run/docker.sock"
- "$$BUILDKITE_DOCKER_CONFIG_TEMP_DIRECTORY/config.json:/root/.docker/config.json"
propagate-environment: true
environment:
- "BUILDKITE_DOCKER_CONFIG_TEMP_DIRECTORY"
You can read more about runtime variable interpolation from the docs.
load
If the image that you want to run is not in a registry the load
property can be used to load an image from a tar file.
This can be useful if a previous step builds an image and uploads it as an artifact. The below example shows how a artifact can be downloaded and then passed to the load
property to load the image which can then be referred to in the image
property to start a container and run a command as explained above.
steps:
- command: "npm start"
plugins:
- artifacts#v1.9.0:
download: "node-7-image.tar.gz"
- docker#v5.12.0:
load: "node-7-image.tar.gz"
image: "node:7"
🚨 Warning
You need to be careful when/if running the BuildKite agent itself in docker that, itself, runs pipelines that use this plugin. Make sure to read all the documentation on the matter, specially the caveats and warnings listed.
Configuration
Required
image
(required, string)
The name of the Docker image to use.
Example: node:7
Optional
add-host
(optional, array)
Additional lines can be added to /etc/hosts
in the container, in an array of mappings. See https://docs.docker.com/engine/reference/run/#managing-etchosts for more details.
Example: buildkite.fake:123.0.0.7
additional-groups
(optional, array)
Additional groups to be added to the user in the container, in an array of group names (or ids). See https://docs.docker.com/engine/reference/run/#additional-groups for more details.
Example: docker
always-pull
(optional, boolean)
Whether to always pull the latest image before running the command. Useful if the image has a latest
tag.
Default: false
command
(optional, array)
Sets the command for the Docker image, and defaults the shell
option to false
. Useful if the Docker image has an entrypoint, or doesn't contain a shell.
This option can't be used if your step already has a top-level, non-plugin command
option present.
Examples: [ "/bin/mycommand", "-c", "test" ]
, ["arg1", "arg2"]
debug
(optional, boolean)
Enables debug mode, which outputs the full Docker commands that will be run on the agent machine.
Default: false
device-read-bps
(optional, array)
Limit read rate from a device (format: <device-path>:<number>[<unit>]
). Number is a positive integer. Unit can be one of kb
, mb
, or gb
.
Example: ["/dev/sda1:200mb"]
device-read-iops
(optional, array)
Limit read rate (IO per second) from a device (format: <device-path>:<number>
). Number is a positive integer.
Example: ["/dev/sda1:400"]
device-write-bps
(optional, array)
Limit write rate to a device (format: <device-path>:<number>[<unit>]
). Number is a positive integer. Unit can be one of kb
, mb
, or gb
.
Example: ["/dev/sda1:200mb"]
device-write-iops
(optional, array)
Limit write rate (IO per second) to a device (format: <device-path>:<number>
). Number is a positive integer.
Example: ["/dev/sda1:400"]
entrypoint
(optional, string)
Override the image’s default entrypoint, and defaults the shell
option to false
. See the docker run --entrypoint documentation for more details. Set it to ""
(empty string) to disable the default entrypoint for the image, but note that you may need to use this plugin's command
option instead of the top-level command
option or set a shell
instead (depending on the command you want/need to run - see Issue 138 for more information).
Example: /my/custom/entrypoint.sh
, ""
environment
(optional, array)
An array of additional environment variables to pass into to the docker container. Items can be specified as either KEY
or KEY=value
. Each entry corresponds to a Docker CLI --env
parameter. Values specified as variable names will be passed through from the outer environment.
Example: [ "BUILDKITE_MESSAGE", "MY_SECRET_KEY", "MY_SPECIAL_BUT_PUBLIC_VALUE=kittens" ]
env-file
(optional, array)
An array of additional files to pass into to the docker container as environment variables. Each entry corresponds to a Docker CLI --env-file
parameter.
env-propagation-list
(optional, string)
If you set this to VALUE
, and VALUE
is an environment variable containing a space-separated list of environment variables such as A B C D
, then A, B, C, and D will all be propagated to the container. This is helpful when you've set up an environment
hook to export secrets as environment variables, and you'd also like to programmatically ensure that secrets get propagated to containers, instead of listing them all out.
expand-image-vars
(optional, boolean, unsafe)
When set to true, it will activate interpolation of variables in the elements of the image
configuration variable. When turned off (the default), attempting to use variables will fail as the literal $VARIABLE_NAME
string will be passed as the image name.
Environment variable interporation rules apply here. $VARIABLE_NAME
is resolved at pipeline upload time, whereas $$VARIABLE_NAME
is at run time. All things being equal, you likely want $$VARIABLE_NAME
.
:warning: Important: this is considered an unsafe option as the most compatible way to achieve this is to run the strings through eval
which could lead to arbitrary code execution or information leaking if you don't have complete control of the pipeline
propagate-environment
(optional, boolean)
Whether or not to automatically propagate all* pipeline environment variables into the docker container. Avoiding the need to be specified with environment
.
Note that only pipeline variables will automatically be propagated (what you see in the Buildkite UI). Variables set in proceeding hook scripts will not be propagated to the container.
* Caveat: only environment variables listed in $BUILDKITE_ENV_FILE will be propagated. This does not include e.g. variables that you exported in an environment
hook. If you wish for those to be propagated, try env-propagation-list
.
propagate-aws-auth-tokens
(optional, boolean)
Whether or not to automatically propagate aws authentication environment variables into the docker container. Avoiding the need to be specified with environment
. This is useful for example if you are using an assume role plugin or you want to pass the role of an agent running in ECS or EKS to the docker container.
Will propagate AWS_ACCESS_KEY_ID
, AWS_SECRET_ACCESS_KEY
, AWS_SESSION_TOKEN
, AWS_REGION
, AWS_DEFAULT_REGION
, AWS_STS_REGIONAL_ENDPOINTS
, AWS_WEB_IDENTITY_TOKEN_FILE
, AWS_ROLE_ARN
, AWS_CONTAINER_CREDENTIALS_FULL_URI
, AWS_CONTAINER_CREDENTIALS_RELATIVE_URI
, and AWS_CONTAINER_AUTHORIZATION_TOKEN
, only if they are set already.
When the AWS_WEB_IDENTITY_TOKEN_FILE
is specified, it will also mount it automatically for you and make it usable within the container.
propagate-gcp-auth-tokens
(optional, boolean)
Whether or not to automatically propagate gcp auth credentials into the docker container. Avoiding the need to be specified with environment
. This is useful if you are using a workload identity federation to impersonate a service account and you want to pass it to the docker container. This is compatible with the gcp-workload-identity-federation
plugin.
Will propagate GOOGLE_APPLICATION_CREDENTIALS
, CLOUDSDK_AUTH_CREDENTIAL_FILE_OVERRIDE
and BUILDKITE_OIDC_TMPDIR
and also mount the dir specified by BUILDKITE_OIDC_TMPDIR
into the container.
propagate-uid-gid
(optional, boolean)
Whether to match the user ID and group ID for the container user to the user ID and group ID for the host user. It is similar to specifying user: 1000:1000
, except it avoids hardcoding a particular user/group ID.
Using this option ensures that any files created on shared mounts from within the container will be accessible to the host user. It is otherwise common to accidentally create root-owned files that the agent will be unable to remove, since a lot of images by default run as the root user. This can also be mitigated for the checkout directory by using the chown
option of this plugin.
privileged
(optional, boolean)
Whether or not to run the container in privileged mode
init
(optional, boolean)
Whether or not to run an init process inside the container. This ensures that responsibilities like reaping zombie processes are performed inside the container.
See Docker's documentation for background and implementation details.
Default: true
for Linux and macOS, false
for Windows.
leave-container
(optional, boolean)
Whether or not to leave the container after the run, or immediately remove it with --rm
.
Default: false
load
(optional, string)
Specify a file to load a docker image from. If omitted no load will be done.
mount-checkout
(optional, boolean)
Whether to automatically mount the current working directory which contains your checked out codebase. Mounts onto /workdir
, unless workdir
is set, in which case that will be used.
If there's a git mirror path and mount-checkout
is enabled, the (mirror path)[https://buildkite.com/docs/pipelines/environment-variables#BUILDKITE_REPO_MIRROR] is mounted into the docker container as an added volume. Otherwise, the git mirror path will have to be explicitly added as an extra volume to mount into the container.
Default: true
chown
(optional, boolean)
Whether to chown
the directory mounted with mount-checkout
to the Buildkite agent user before exiting, to ensure that the agent can clean up any additional files created there. This will happen even if the command fails or is cancelled. This option has no effect on Windows or if mount-checkout
is false.
Prefer using propagate-uid-gid
over this option, as the chown
–which can take some time if your checkout is of considerable size—is likely not needed at all in that case.
Default: false
chown-image
(optional, string)
The Docker image in which to run the chown
command.
Default: busybox
mount-buildkite-agent
(optional, boolean)
Whether to automatically mount the buildkite-agent
binary from the host agent machine into the container.
Set to true
if you want to enable and are sure that the binary running in the agent is compatible with the container's architecture and environment (for example, don't try to mount the OS X or Windows agent binary in a container running linux). If enabled in Windows agents your pipeline, step or agent must have the BUILDKITE_AGENT_BINARY_PATH
environment variable defined with the executable to mount in the (Windows) agent.
Default: false
Important: enabling this option will share the BUILDKITE_AGENT_TOKEN
and BUILDKITE_AGENT_JOB_API_TOKEN
environment variables (and other related ones) with the container if present.
mount-ssh-agent
(optional, boolean or string)
Whether to mount the ssh-agent socket (at /ssh-agent
) from the host agent machine into the container or not. Instead of just true
or false
, you can specify absolute path in the container for the home directory of the user used to run on which the agent's .ssh/known_hosts
will be mounted (by default, /root
).
Default: false
Important: note that for this to work you will need the agent itself to have access to an ssh agent that is: up and running, listening on the appropriate socket, with the appropriate credentials loaded (or to be loaded). Please refer to the agent's documentation on using SSH agent for more information
network
(optional, string)
Join the container to the docker network specified. The network will be created if it does not already exist. See https://docs.docker.com/engine/reference/run/#network-settings for more details.
Example: test-network
platform
(optional, string)
Platform defines the target platform containers for this service will run on, using the os[/arch[/variant]] syntax. The values of os, arch, and variant MUST conform to the convention used by the OCI Image Spec.
Example: linux/arm64
pid
(optional, string)
PID namespace provides separation of processes. The PID Namespace removes the view of the system processes, and allows process ids to be reused including pid 1. See https://docs.docker.com/engine/reference/run/#pid-settings---pid for more details. By default, all containers have the PID namespace enabled.
Example: host
gpus
(optional, string)
GPUs selector. Dependencies: nvidia-container-runtime
Example: all
pull-retries
(optional, int)
A number of times to retry failed docker pull. Defaults to 3. Only applies when always-pull
is enabled.
runtime
(optional, string)
Specify an explicit docker runtime. See the docker run options documentation for more details.
Example: nvidia
ipc
(optional, string)
Specify the IPC mode to use. See the docker run options documentation for more details.
Example: host
run-labels
(optional, boolean)
If set to true, adds useful Docker labels to the container. See Container Labels for more info.
The default is true
.
shell
(optional, array or boolean)
Set the shell to use for the command. Set it to false
to pass the command directly to the docker run
command. The default is ["/bin/sh", "-e", "-c"]
unless you have provided an entrypoint
or command
.
Example: [ "powershell", "-Command" ]
shm-size
(optional, string)
Set the size of the /dev/shm
shared memory filesystem mount inside the docker contianer. If unset, uses the default for the platform (typically 64mb
). See docker run’s runtime constraints documentation for information on allowed formats.
Example: 2gb
skip-checkout
(optional, boolean)
Whether to skip the repository checkout phase.
Default: false
storage-opt
(optional, string)
This allows setting the container rootfs size at the creation time. This is only available for the devicemapper
, btrfs
, overlay2
, windowsfilter
and zfs
graph drivers. See docker documentation for more details.
Example: size=120G
tty
(optional, boolean)
If set to false, doesn't allocate a TTY. This is useful in some situations where TTY's aren't supported, for instance windows.
Default: true
for Linux and macOS, and false
for Windows.
interactive
(optional, boolean)
If set to false, doesn't connect stdin
to the process. Some scripts fall back to asking for user input in case of errors, if the process has stdin
connected and this results in the process waiting for input indefinitely.
user
(optional, string)
Allows a user to be set, and override the USER entry in the Dockerfile. See https://docs.docker.com/engine/reference/run/#user for more details.
Example: root
userns
(optional, string)
Allows to explicitly set the user namespace. This overrides the default docker daemon value. If you use the value host
, you disable user namespaces for this run. See https://docs.docker.com/engine/security/userns-remap/ for more details. Due to limitations in this feature, a privileged container will override the user specified userns
value to host
Example: mynamespace
volumes
(optional, array or boolean)
Extra volume mounts to pass to the docker container, in an array. Items are specified as SOURCE:TARGET
. Each entry corresponds to a Docker CLI --volume
parameter. Relative local paths are converted to their full-path (e.g ./code:/app
).
Example: [ "/var/run/docker.sock:/var/run/docker.sock" ]
expand-volume-vars
(optional, boolean, run only, unsafe)
When set to true, it will activate interpolation of variables in the elements of the volumes
configuration array as well as workdir
. When turned off (the default), attempting to use variables will fail as the literal $VARIABLE_NAME
string will be passed to the -v
option.
Environment variable interporation rules apply here. $VARIABLE_NAME
is resolved at pipeline upload time, whereas $$VARIABLE_NAME
is at run time. All things being equal, you likely want $$VARIABLE_NAME
.
:warning: Important: this is considered an unsafe option as the most compatible way to achieve this is to run the strings through eval
which could lead to arbitrary code execution or information leaking if you don't have complete control of the pipeline
tmpfs
(optional, array)
Tmpfs mounts to pass to the docker container, in an array. Each entry corresponds to a Docker CLI --tmpfs
parameter. See Docker's tmpfs mounts documentation for more information on this feature.
Example: [ "/tmp", "/root/.cache" ]
workdir
(optional, string)
The working directory to run the command in, inside the container. The default is /workdir
. This path is also used by mount-checkout
to determine where to mount the checkout in the container.
Example: /app
sysctls
(optional, array)
Set namespaced kernel parameters in the container. More information can be found in https://docs.docker.com/engine/reference/commandline/run/.
Example: --sysctl net.ipv4.ip_forward=1
add-caps
(optional, array)
Add Linux capabilities to the container. Each entry corresponds to a Docker CLI --cap-add
parameter.
drop-caps
(optional, array)
Remove Linux capabilities from the container. Each entry corresponds to a Docker CLI --cap-drop
parameter.
security-opts
(optional, array)
Add security options to the container. Each entry corresponds to a Docker CLI --security-opt
parameter.
ulimits
(optional, array)
Add ulimit options to the container. Each entry corresponds to a Docker CLI --ulimit
parameter.
devices
(optional, array)
You can give builds limited access to a specific device or devices by passing devices to the docker container, in an array. Items are specific as SOURCE:TARGET
or just TARGET
. Each entry corresponds to a Docker CLI --device
parameter.
Example: [ "/dev/bus/usb/001/001" ]
publish
(optional, array)
You can allow the docker container to publish ports. More information can be found in https://docs.docker.com/config/containers/container-networking/. Each entry corresponds to a Docker CLI --publish
or -p
parameter.
Example: [ "8080:80" ]
(Map TCP port 80 in the container to port 8080 on the Docker host.)
cpus
(optional, string)
Set the CPU limit to apply when running the container. More information can be found in https://docs.docker.com/config/containers/resource_constraints/#cpu.
Example: 0.5
memory
(optional, string)
Set the memory limit to apply when running the container. More information can be found in https://docs.docker.com/config/containers/resource_constraints/#limit-a-containers-access-to-memory.
Example: 2g
memory-swap
(optional, string)
Set the memory swap limit to apply when running the container. More information can be found in https://docs.docker.com/config/containers/resource_constraints/#limit-a-containers-access-to-memory.
Example: 2g
memory-swappiness
(optional, string)
Set the swappiness level to apply when running the container. More information can be found in https://docs.docker.com/config/containers/resource_constraints/#--memory-swappiness-details.
Example: 0
Container Labels
When running a command, the plugin will automatically add the following Docker labels to the container:
com.buildkite.pipeline_name=${BUILDKITE_PIPELINE_NAME}
com.buildkite.pipeline_slug=${BUILDKITE_PIPELINE_SLUG}
com.buildkite.build_number=${BUILDKITE_BUILD_NUMBER}
com.buildkite.job_id=${BUILDKITE_JOB_ID}
com.buildkite.job_label=${BUILDKITE_LABEL}
com.buildkite.step_key=${BUILDKITE_STEP_KEY}
com.buildkite.agent_name=${BUILDKITE_AGENT_NAME}
com.buildkite.agent_id=${BUILDKITE_AGENT_ID}
These labels can make it easier to query containers on hosts using docker ps
for example:
docker ps --filter "label=com.buildkite.job_label=Run tests"
This behaviour can be disabled with the run-labels: false
option.
Developing
To run testing, shellchecks and plugin linting use use bk run
with the Buildkite CLI.
bk run
Or if you want to run just the tests, you can use the docker Plugin Tester:
docker run --rm -ti -v "${PWD}":/plugin buildkite/plugin-tester:latest
License
MIT (see LICENSE)