BUILD-273 Volumes override by Build and BuildRun

Build and BuildRun objects can now override volumes defined by
BuildStrategy in case they are overridable.
Only overridable volumes are allowed to be overriden.

pkg/apis/build/v1alpha1/build_types.go

@@ -138,6 +138,11 @@ type BuildSpec struct {
 	// Env contains additional environment variables that should be passed to the build container
 	// +optional
 	Env []corev1.EnvVar `json:"env,omitempty"`
+
+	// Volumes contains volume Overrides of the BuildStrategy volumes in case those are allowed
+	// to be overriden. Must only contain volumes that exist in the corresponding BuildStrategy
+	// +optional
+	Volumes []BuildVolume `json:"volumes,omitempty"`
 }
 
 // StrategyName returns the name of the configured strategy, or 'undefined' in

pkg/apis/build/v1alpha1/buildrun_types.go

@@ -59,6 +59,11 @@ type BuildRunSpec struct {
 	// Env contains additional environment variables that should be passed to the build container
 	// +optional
 	Env []corev1.EnvVar `json:"env,omitempty"`
+
+	// Volumes contains volume Overrides of the BuildStrategy volumes in case those are allowed
+	// to be overriden. Must only contain volumes that exist in the corresponding BuildStrategy
+	// +optional
+	Volumes []BuildVolume `json:"volumes,omitempty"`
 }
 
 // BuildRunRequestedState defines the buildrun state the user can provide to override whatever is the current state.

pkg/reconciler/buildrun/resources/taskrun.go

@@ -236,7 +236,7 @@ func GenerateTaskSpec(
 
 	// Add volumes from the strategy to generated task spec
 	// will have to add buildrun volumes here for merging later, too
-	volumes, err := volumes.TaskSpecVolumes(existingVolumeMounts, buildVolumes, nil)
+	volumes, err := volumes.TaskSpecVolumes(existingVolumeMounts, buildVolumes, build.Spec.Volumes, buildRun.Spec.Volumes)
 	if err != nil {
 		return nil, err
 	}

pkg/volumes/volumes.go

@@ -33,11 +33,19 @@ func NewStepVolumeMount(name string, readOnly bool) StepVolumeMount {
 func TaskSpecVolumes(
 	existingVolumeMounts []StepVolumeMount,
 	strategyVolumes []buildv1alpha1.BuildVolume,
+	buildVolumes []buildv1alpha1.BuildVolume,
 	buildrunVolumes []buildv1alpha1.BuildVolume,
 ) ([]corev1.Volume, error) {
 	res := []corev1.Volume{}
 
-	volumes, err := MergeBuildVolumes(strategyVolumes, buildrunVolumes)
+	// first we merge build volumes into the strategy ones, next we merge
+	// build run volumes into result of the previous merge.
+	// eventual list of volumes will be added to the generated TaskSpec object
+	volumes, err := MergeBuildVolumes(strategyVolumes, buildVolumes)
+	if err != nil {
+		return nil, err
+	}
+	volumes, err = MergeBuildVolumes(volumes, buildrunVolumes)
 	if err != nil {
 		return nil, err
 	}
@@ -79,7 +87,7 @@ func TaskSpecVolumes(
 // MergeBuildVolumes merges Build Volumes from one list into the other. It only allows to merge those that have property
 // Overridable set to true. In case it is empty or false, it is not allowed to be overridden, so Volume cannot be merged
 // Merging in this context means copying the VolumeSource from one object to the other.
-func MergeBuildVolumes(new []buildv1alpha1.BuildVolume, into []buildv1alpha1.BuildVolume) ([]buildv1alpha1.BuildVolume, error) {
+func MergeBuildVolumes(into []buildv1alpha1.BuildVolume, new []buildv1alpha1.BuildVolume) ([]buildv1alpha1.BuildVolume, error) {
 	if len(new) == 0 && len(into) == 0 {
 		return []buildv1alpha1.BuildVolume{}, nil
 	}