Cloud Native Buildpacks
Cloud Native Buildpacks enable building a container image from source code without the need for a Dockerfile.
Skaffold supports building with Cloud Native Buildpacks, requiring only
a local Docker daemon. Skaffold performs the build inside a container
using the builder specified in the buildpack config.
On successful build completion, the built image will be pushed to the remote registry. You can choose to skip this step.
Configuration
To use Buildpacks, add a buildpack field to each artifact you specify in the
artifacts part of the build section. context should be a path to
your source.
Note
In Skaffold 1.11 (schemav2beta5), the singular buildpack field was renamed to buildpacks.
The following options can optionally be configured:
| Option | Description | Default |
|---|---|---|
builder |
builder image used. | |
runImage |
overrides the stack’s default run image. | |
env |
environment variables, in the key=value form, passed to the build. Values can use the go template syntax. |
[] |
buildpacks |
a list of strings, where each string is a specific buildpack to use with the builder. If you specify buildpacks the builder image automatic detection will be ignored. These buildpacks will be used to build the Image from your source code. Order matters. | [] |
trustBuilder |
indicates that the builder should be trusted. | false |
clearCache |
removes old cache volume associated with the specific image and supplies a clean cache volume for build. | false |
projectDescriptor |
path to the project descriptor file. | project.toml |
dependencies |
file dependencies that skaffold should watch for both rebuilding and file syncing for this artifact. | |
volumes |
support mounting host volumes into the container. | |
Builder
builder is required and tells Skaffold which
Builder to use.
Run Image
runImage is optional and will override the default Run Image.
Artifact Dependency
You can define dependency on other artifacts using the requires keyword. This can be useful to specify another artifact image as the builder or runImage.
build:
artifacts:
- image: image1 # buildpacks artifact
buildpacks:
builder: image2
runImage: image3
requires:
- image: image2
- image: image3
- image: image2 # builder artifact
- image: image3 # run image artifact
local: {}
User defined environment variables
env makes it possible to configure specific environment variables for buildpacks.
Many buildpacks use environment variables to adjust their detection and the build phases,
such as selecting specific versions of language runtimes.
Note that user’s current environment is not passed through to buildpacks.
Example
The following build section, instructs Skaffold to build a
Docker image with buildpacks:
apiVersion: skaffold/v2beta5
kind: Config
build:
artifacts:
- image: gcr.io/k8s-skaffold/skaffold-buildpacks
buildpacks:
builder: "gcr.io/buildpacks/builder:v1"
Dependencies
dependencies tells the skaffold file watcher which files should be watched to
trigger rebuilds and file syncs. Supported schema for dependencies includes:
| Option | Description | Default |
|---|---|---|
paths |
should be set to the file dependencies for this artifact, so that the skaffold file watcher knows when to rebuild and perform file synchronization. | [] |
ignore |
specifies the paths that should be ignored by skaffold’s file watcher. If a file exists in both paths and in ignore, it will be ignored, and will be excluded from both rebuilds and file synchronization. Will only work in conjunction with paths. |
[] |
By default, every file in the artifact’s context will be watched.
Paths and Ignore
Paths and Ignore are arrays used to list dependencies.
Any paths in Ignore will be ignored by the skaffold file watcher, even if they are also specified in Paths.
Ignore will only work in conjunction with Paths, and with none of the other custom artifact dependency types.
buildpack:
builder: "gcr.io/buildpacks/builder:v1"
dependencies:
paths:
- pkg/**
- src/*.go
ignore:
- vendor/**