Builders

Building Plans

A builder is a component that takes a plan source code, and optionally the SDK's source code, and compiles it into a build artifact, ready to be used by compatible Runners to schedule test workloads on Testground.

The build process is different depending on the language of the plan, and the kind of build artifact being targeted. Here's a simple diagram to understand how builders and runners relate to one another.

                      ☟
-------------    -----------    ------------------    ----------    ---------------
| plan code | -> | builder | -> | build artifact | -> | runner | -> | test output |
-------------    -----------    ------------------    ----------    ---------------

Supported builders

Builder names follow the format: <build artifact type>:<language>

builder	input language	output type	compatible runners
exec:go	Go	OS-specific executable	local:exec
docker:go	Go	Docker image	local:docker, cluster:k8s
docker:generic	Any	Docker image	local:docker, cluster:k8s

Builder configuration options

The builders accept options on the command-line which can customize their behaviour. Each builder has a different set of configurable options. This section lists the configuration options supported by each.

Builder configuration options can be provided by various means, in the following order of precedence (highest precedence to lowest precedence):

1. CLI --build-cfg flags for single commands, and in the composition file for composition commands.

2. .env.toml: [builders] section.

3. Test plan manifest.

4. Builder defaults (applied by the runner).

exec:go builder

The exec:go builder uses the machine's own Go installation to compile and build a binary. Below are the options this builder supports. None of these are required and need only be edited if the defaults do not work well in your environment.‌

options	explanation
module_path	gomod path with fresh_gomod
exec_pkg	specify the package to build
fresh_gomod	remove and recreate go.mod files

docker:go builder

The docker:go builder uses the user's local Docker daemon to construct a Docker image. By default, the docker:go builder will leverage a goproxy container to speed up fetching of Go modules. Additionally, all builds are performed on an isolated Docker network.‌

None of these options are required and need only be edited if the defaults do not work well in your environment.‌

option	explanation
go_version	override the version of Go used to compile the plan
module_path	gomod path with fresh_gomod
exec_pkg	specify the package to build
fresh_gomod	remove and recreate go.mod files
push_registry	after build, push docker image to a remote registry
registry_type	must be set if push_registry is true. Set to aws or dockerhub
go_proxy_mode	how to access go proxy. By default, use a local container.
go_proxy_url	required if go_proxy_mode is custom. Use a custom go_proxy instance.

Examples

Single build for a single test for the example/output plan using the exec:go builder. This command will produce a binary which you can find in ~/testground/ on Linux and macOS systems.

$ testground build single --plan=example --builder=exec:go --wait

Same, using the docker:go builder. This command will produce a Docker image.

$ testground build single --plan=example --builder=docker:go --wait

Use the docker:go builder to build an image and then push the image to DockerHub (configure credentials in env.toml file).

$ testground build single --plan=example --builder=docker:go \
                                         --build-cfg push_registry=true \
                                         --build-cfg registry_type=dockerhub \
                                         --wait

Build a composition defined in barrier-local.toml. Note that the composition file will contain the builder and runner so specifying the builder on the command-line is not used in this example.

$ testground build composition --file=compositions/barrier-local.toml \
                               --write-artifacts \
                               --wait