Build
Skaffold supports different tools for building images:
| Local Build | In Cluster Build | Remote on Google Cloud Build | |
|---|---|---|---|
| Dockerfile | Yes | Yes | Yes |
| Jib Maven and Gradle | Yes | - | Yes |
| Cloud Native Buildpacks | Yes | - | Yes |
| Bazel | Yes | - | - |
| Custom Script | Yes | Yes | - |
Configuration
The build section in the Skaffold configuration file, skaffold.yaml,
controls how artifacts are built. To use a specific tool for building
artifacts, add the value representing the tool and options for using that tool
to the build section.
For a detailed discussion on Skaffold Configuration, see skaffold.yaml References.
Local Build
Local build execution is the default execution context. Skaffold will use your locally-installed build tools (such as Docker, Bazel, Maven or Gradle) to execute the build.
Configuration
To configure the local execution explicitly, add build type local to the build section of skaffold.yaml
build:
local: {}
The following options can optionally be configured:
| Option | Description | Default |
|---|---|---|
push |
should images be pushed to a registry. If not specified, images are pushed only if the current Kubernetes context connects to a remote cluster. | |
useDockerCLI |
use docker command-line interface instead of Docker Engine APIs. |
false |
useBuildkit |
use BuildKit to build Docker images. | false |
concurrency |
how many artifacts can be built concurrently. 0 means “no-limit”. | 1 |
Faster builds
When deploying to a local cluster,
Skaffold will default push to false to speed up builds.
Skaffold can build artifacts in parallel by setting concurrency to a value other than 1, and 0 means there are no limits.
For local builds, this is however disabled by default since local builds could have side effects that are
not compatible with parallel builds. Feel free to increase the concurrency if you know that your builds
can run in parallel.
Note
When artifacts are built in parallel, the build logs are still printed in sequence to make them easier to read.In Cluster Build
Skaffold supports building in cluster via Kaniko or Custom Build Script.
Configuration
To configure in-cluster Build, add build type cluster to the build section of skaffold.yaml.
build:
cluster: {}
The following options can optionally be configured:
| Option | Description | Default |
|---|---|---|
HTTP_PROXY |
for kaniko pod. | |
HTTPS_PROXY |
for kaniko pod. | |
pullSecret |
path to the Google Cloud service account secret key file. | |
pullSecretName |
name of the Kubernetes secret for pulling base images and pushing the final image. If given, the secret needs to contain the Google Cloud service account secret key under the key kaniko-secret. |
kaniko-secret |
pullSecretMountPath |
path the pull secret will be mounted at within the running container. | |
namespace |
Kubernetes namespace. Defaults to current namespace in Kubernetes configuration. | |
timeout |
amount of time (in seconds) that this build is allowed to run. Defaults to 20 minutes (20m). |
|
dockerConfig |
describes how to mount the local Docker configuration into a pod. | |
serviceAccount |
describes the Kubernetes service account to use for the pod. Defaults to ‘default’. | |
runAsUser |
defines the UID to request for running the container. If omitted, no SeurityContext will be specified for the pod and will therefore be inherited from the service account. | |
resources |
define the resource requirements for the kaniko pod. | |
concurrency |
how many artifacts can be built concurrently. 0 means “no-limit”. | 0 |
volumes |
defines container mounts for ConfigMap and Secret resources. | [] |
randomPullSecret |
adds a random UUID postfix to the default name of the pull secret to facilitate parallel builds, e.g. kaniko-secretdocker-cfgfd154022-c761-416f-8eb3-cf8258450b85. | false |
randomDockerConfigSecret |
adds a random UUID postfix to the default name of the docker secret to facilitate parallel builds, e.g. docker-cfgfd154022-c761-416f-8eb3-cf8258450b85. | false |
Faster builds
Skaffold can build multiple artifacts in parallel, by settings a value higher than 1 to concurrency.
For in-cluster builds, the default is to build all the artifacts in parallel. If your cluster is too
small, you might want to reduce the concurrency. Setting concurrency to 1 will cause artifacts to be built sequentially.
Note
When artifacts are built in parallel, the build logs are still printed in sequence to make them easier to read.Remotely on Google Cloud Build
Skaffold supports building remotely with Google Cloud Build.
Google Cloud Build is a Google Cloud Platform service that executes your builds using Google infrastructure. To get started with Google Build, see Cloud Build Quickstart.
Skaffold can automatically connect to Cloud Build, and run your builds with it. After Cloud Build finishes building your artifacts, they will be saved to the specified remote registry, such as Google Container Registry.
Skaffold Google Cloud Build process differs from the gcloud command
gcloud builds submit. Skaffold will create a list of dependent files
and submit a tar file to GCB. It will then generate a single step cloudbuild.yaml
and will start the building process. Skaffold does not honor .gitignore or .gcloudignore
exclusions. If you need to ignore files use .dockerignore. Any cloudbuild.yaml found will not
be used in the build process.
Configuration
To use Cloud Build, add build type googleCloudBuild to the build
section of skaffold.yaml.
build:
googleCloudBuild: {}
The following options can optionally be configured:
| Option | Description | Default |
|---|---|---|
projectId |
ID of your Cloud Platform Project. If it is not provided, Skaffold will guess it from the image name. For example, given the artifact image name gcr.io/myproject/image, Skaffold will use the myproject GCP project. |
|
diskSizeGb |
disk size of the VM that runs the build. See Cloud Build Reference. | |
machineType |
type of the VM that runs the build. See Cloud Build Reference. | |
timeout |
amount of time (in seconds) that this build should be allowed to run. See Cloud Build Reference. | |
logging |
specifies the logging mode. Valid modes are: LOGGING_UNSPECIFIED: The service determines the logging mode. LEGACY: Stackdriver logging and Cloud Storage logging are enabled (default). GCS_ONLY: Only Cloud Storage logging is enabled. See Cloud Build Reference. |
|
logStreamingOption |
specifies the behavior when writing build logs to Google Cloud Storage. Valid options are: STREAM_DEFAULT: Service may automatically determine build log streaming behavior. STREAM_ON: Build logs should be streamed to Google Cloud Storage. STREAM_OFF: Build logs should not be streamed to Google Cloud Storage; they will be written when the build is completed. See Cloud Build Reference. |
|
dockerImage |
image that runs a Docker build. See Cloud Builders. | gcr.io/cloud-builders/docker |
kanikoImage |
image that runs a Kaniko build. See Cloud Builders. | gcr.io/kaniko-project/executor |
mavenImage |
image that runs a Maven build. See Cloud Builders. | gcr.io/cloud-builders/mvn |
gradleImage |
image that runs a Gradle build. See Cloud Builders. | gcr.io/cloud-builders/gradle |
packImage |
image that runs a Cloud Native Buildpacks build. See Cloud Builders. | gcr.io/k8s-skaffold/pack |
concurrency |
how many artifacts can be built concurrently. 0 means “no-limit”. | 0 |
Faster builds
Skaffold can build multiple artifacts in parallel, by settings a value higher than 1 to concurrency.
For Google Cloud Build, the default is to build all the artifacts in parallel. If you hit a quota restriction,
you might want to reduce the concurrency.
Note
When artifacts are built in parallel, the build logs are still printed in sequence to make them easier to read.Restrictions
Skaffold currently supports Docker, Jib on Google Cloud Build.