Adding Volumes support to Build Strategies

This commit adds Volumes support to Build Strategies, Builds and
BuildRuns, allowing user to configure volumes and volume mounts
used by the future tekton TaskRun object.
Volumes can be overridden by Build and BuildRun objects.

deploy/200-role.yaml

@@ -75,6 +75,10 @@ rules:
   resources: ['secrets']
   verbs:     ['get', 'list', 'watch']
 
+- apiGroups: ['']
+  resources: ['configmaps']
+  verbs:     ['list']
+
 - apiGroups: ['']
   resources: ['serviceaccounts']
   verbs:     ['get', 'list', 'watch', 'create', 'update', 'delete']

docs/build.md

@@ -16,6 +16,7 @@ SPDX-License-Identifier: Apache-2.0
   - [Defining the Builder or Dockerfile](#defining-the-builder-or-dockerfile)
   - [Defining the Output](#defining-the-output)
   - [Defining Retention Parameters](#defining-retention-parameters)
+  - [Defining Volumes](#defining-volumes)
 - [BuildRun deletion](#BuildRun-deletion)
 
 ## Overview
@@ -571,6 +572,36 @@ An example of a user using both TTL and Limit retention fields. In case of such
 
 **NOTE**: When changes are made to `retention.failedLimit` and `retention.succeededLimit` values, they come into effect as soon as the build is applied, thereby enforcing the new limits. On the other hand, changing the `retention.ttlAfterFailed` and `retention.ttlAfterSucceeded` values will only affect new buildruns. Old buildruns will adhere to the old TTL retention values. In case TTL values are defined in buildrun specifications as well as build specifications, priority will be given to the values defined in the buildrun specifications.
 
+### Defining Volumes
+
+`Builds` can declare `volumes`. They must override `volumes` defined by the according `BuildStrategy`. If a `volume`
+is not `overridable` then the `BuildRun` will eventually fail.
+
+`Volumes` follow the declaration of [Pod Volumes](https://kubernetes.io/docs/concepts/storage/volumes/), so 
+all the usual `volumeSource` types are supported.
+
+Here is an example of `Build` object that overrides `volumes`:
+
+```yaml
+apiVersion: shipwright.io/v1alpha1
+kind: Build
+metadata:
+  name: build-name
+spec:
+  source:
+    url: https://github.com/example/url
+  strategy:
+    name: buildah
+    kind: ClusterBuildStrategy
+  dockerfile: Dockerfile
+  output:
+    image: registry/namespace/image:latest
+  volumes:
+    - name: volume-name
+      configMap:
+        name: test-config
+```
+
 ### Sources
 
 Sources represent remote artifacts, as in external entities added to the build context before the actual Build starts. Therefore, you may employ `.spec.sources` to download artifacts from external repositories.

docs/buildrun.md

@@ -14,6 +14,7 @@ SPDX-License-Identifier: Apache-2.0
   - [Defining ParamValues](#defining-paramvalues)
   - [Defining the ServiceAccount](#defining-the-serviceaccount)
   - [Defining Retention Parameters](#defining-retention-parameters)
+  - [Defining Volumes](#defining-volumes)
 - [Canceling a `BuildRun`](#canceling-a-buildrun)
 - [Automatic `BuildRun` deletion](#automatic-buildrun-deletion)
 - [Specifying Environment Variables](#specifying-environment-variables)
@@ -194,6 +195,33 @@ spec:
 
 **NOTE** In case TTL values are defined in buildrun specifications as well as build specifications, priority will be given to the values defined in the buildrun specifications.
 
+### Defining Volumes
+
+`BuildRuns` can declare `volumes`. They must override `volumes` defined by the according `BuildStrategy`. If a `volume`
+is not `overridable` then the `BuildRun` will eventually fail.
+
+In case `Build` and `BuildRun` that refers to this `Build` override the same `volume`, one that is defined in the `BuildRun`
+is the one used eventually.
+
+`Volumes` follow the declaration of [Pod Volumes](https://kubernetes.io/docs/concepts/storage/volumes/), so 
+all the usual `volumeSource` types are supported.
+
+Here is an example of `BuildRun` object that overrides `volumes`:
+
+```yaml
+apiVersion: shipwright.io/v1alpha1
+kind: BuildRun
+metadata:
+  name: buildrun-name
+spec:
+  buildRef:
+    name: build-name
+  volumes:
+    - name: volume-name
+      configMap:
+        name: test-config
+```
+
 ## Canceling a `BuildRun`
 
 To cancel a `BuildRun` that's currently executing, update its status to mark it as canceled.

docs/buildstrategies.md

@@ -881,9 +881,42 @@ A Kubernetes administrator can further restrict the usage of annotations by usin
 
 ## Volumes and VolumeMounts
 
-Build steps can declare a `volumeMount`, which allows data in the provided path to be shared across build steps.
-When a `volumeMount` is declared, Shipwright will create an `emptyDir` volume with the corresponding name.
-Build steps whose volume mounts share the same name will share the same underlying `emtpyDir` volume.
+Build Strategies can declare `volumes`. These `volumes` can be referred to by the build steps using `volumeMount`.
+Volumes in Build Strategy follow the declaration of [Pod Volumes](https://kubernetes.io/docs/concepts/storage/volumes/), so 
+all the usual `volumeSource` types are supported.
 
-In a future release, build strategy authors will be able to use other volume types for the volume mounts.
-When this feature is introduced, the volume and volume type will need to be explicitly declared.
+Volumes can be overridden by `Build`s and `BuildRun`s, so Build Strategies' volumes support an `overridable` flag, which
+is a boolean, and is `false` by default. In case volume is not overridable, `Build` or `BuildRun` that tries to override it,
+will fail.
+
+Build steps can declare a `volumeMount`, which allows them to access volumes defined by `BuildStrategy`, `Build` or `BuildRun`.
+
+Here is an example of `BuildStrategy` object that defines `volumes` and `volumeMount`s:
+```
+apiVersion: shipwright.io/v1alpha1
+kind: BuildStrategy
+metadata:
+  name: buildah
+spec:
+  buildSteps:
+    - name: build
+      image: quay.io/containers/buildah:v1.23.1
+      workingDir: $(params.shp-source-root)
+      command:
+        - buildah
+        - bud
+        - --tls-verify=false
+        - --layers
+        - -f
+        - $(build.dockerfile)
+        - -t
+        - $(params.shp-output-image)
+        - $(params.shp-source-context)
+      volumeMounts:
+        - name: varlibcontainers
+          mountPath: /var/lib/containers
+  volumes:
+    - name: varlibcontainers
+      overridable: true
+      emptyDir: {}
+```

pkg/apis/build/v1alpha1/build_types.go

@@ -54,6 +54,12 @@ const (
 	RemoteRepositoryUnreachable BuildReason = "RemoteRepositoryUnreachable"
 	// BuildNameInvalid indicates the build name is invalid
 	BuildNameInvalid BuildReason = "BuildNameInvalid"
+	// VolumeDoesNotExist indicates that volume referenced by the Build does not exist, therefore Build cannot be run
+	VolumeDoesNotExist BuildReason = "VolumeDoesNotExist"
+	// VolumeNotOverridable indicates that volume defined by build is not set as overridable in the strategy
+	VolumeNotOverridable BuildReason = "VolumeNotOverridable"
+	// UndefinedVolume indicates that volume defined by build is not found in the strategy
+	UndefinedVolume BuildReason = "UndefinedVolume"
 	// AllValidationsSucceeded indicates a Build was successfully validated
 	AllValidationsSucceeded = "all validations succeeded"
 )
@@ -143,6 +149,26 @@ type BuildSpec struct {
 	//
 	// +optional
 	Retention *BuildRetention `json:"retention,omitempty"`
+
+	// Volumes contains volume Overrides of the BuildStrategy volumes in case those are allowed
+	// to be overridden. Must only contain volumes that exist in the corresponding BuildStrategy
+	// +optional
+	Volumes []BuildVolume `json:"volumes,omitempty"`
+}
+
+// BuildVolume is a volume that will be mounted in build pod during build step
+type BuildVolume struct {
+	// Name of the Build Volume
+	// +required
+	Name string `json:"name"`
+
+	// Description of the Build Volume
+	// +optional
+	Description *string `json:"description,omitempty"`
+
+	// Represents the source of a volume to mount
+	// +required
+	corev1.VolumeSource `json:",inline"`
 }
 
 // StrategyName returns the name of the configured strategy, or 'undefined' in

pkg/apis/build/v1alpha1/buildrun_types.go

@@ -76,6 +76,11 @@ type BuildRunSpec struct {
 	// Contains information about retention params
 	// +optional
 	Retention *BuildRunRetention `json:"retention,omitempty"`
+
+	// Volumes contains volume Overrides of the BuildStrategy volumes in case those are allowed
+	// to be overridden. 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/apis/build/v1alpha1/buildstrategy.go

@@ -18,8 +18,9 @@ const (
 
 // BuildStrategySpec defines the desired state of BuildStrategy
 type BuildStrategySpec struct {
-	BuildSteps []BuildStep `json:"buildSteps,omitempty"`
-	Parameters []Parameter `json:"parameters,omitempty"`
+	BuildSteps []BuildStep           `json:"buildSteps,omitempty"`
+	Parameters []Parameter           `json:"parameters,omitempty"`
+	Volumes    []BuildStrategyVolume `json:"volumes,omitempty"`
 }
 
 // ParameterType indicates the type of a parameter
@@ -59,6 +60,19 @@ type Parameter struct {
 	Defaults *[]string `json:"defaults"`
 }
 
+// BuildStrategyVolume is a volume that will be mounted in build pod during build step
+// of the Build Strategy
+type BuildStrategyVolume struct {
+	// Indicates that this Volume can be overridden in a Build or BuildRun.
+	// Defaults to false
+	// +optional
+	Overridable *bool `json:"overridable,omitempty"`
+
+	// Inline BuildVolume object, same as Build's Volume
+	// +required
+	BuildVolume `json:",inline"`
+}
+
 // BuildStep defines a partial step that needs to run in container for building the image.
 // If the build step declares a volumeMount, Shipwright will create an emptyDir volume mount for the named volume.
 // Build steps which share the same named volume in the volumeMount will share the same underlying emptyDir volume.
@@ -97,4 +111,5 @@ type BuilderStrategy interface {
 	GetResourceLabels() map[string]string
 	GetBuildSteps() []BuildStep
 	GetParameters() []Parameter
+	GetVolumes() []BuildStrategyVolume
 }

pkg/apis/build/v1alpha1/buildstrategy_types.go

@@ -79,6 +79,11 @@ func (s BuildStrategy) GetParameters() []Parameter {
 	return s.Spec.Parameters
 }
 
+// GetVolumes returns the volumes defined by the build strategy
+func (s BuildStrategy) GetVolumes() []BuildStrategyVolume {
+	return s.Spec.Volumes
+}
+
 func init() {
 	SchemeBuilder.Register(&BuildStrategy{}, &BuildStrategyList{})
 }

pkg/apis/build/v1alpha1/clusterbuildstrategy_types.go

@@ -80,6 +80,11 @@ func (s ClusterBuildStrategy) GetParameters() []Parameter {
 	return s.Spec.Parameters
 }
 
+// GetVolumes returns the volumes defined by the build strategy
+func (s ClusterBuildStrategy) GetVolumes() []BuildStrategyVolume {
+	return s.Spec.Volumes
+}
+
 func init() {
 	SchemeBuilder.Register(&ClusterBuildStrategy{}, &ClusterBuildStrategyList{})
 }

pkg/reconciler/buildrun/buildrun.go

@@ -281,6 +281,15 @@ func (r *ReconcileBuildRun) Reconcile(ctx context.Context, request reconcile.Req
 				return reconcile.Result{}, nil
 			}
 
+			// Validate the volumes
+			valid, reason, message = validate.BuildRunVolumes(strategy.GetVolumes(), buildRun.Spec.Volumes)
+			if !valid {
+				if err := resources.UpdateConditionWithFalseStatus(ctx, r.client, buildRun, message, reason); err != nil {
+					return reconcile.Result{}, err
+				}
+				return reconcile.Result{}, nil
+			}
+
 			// Create the TaskRun, this needs to be the last step in this block to be idempotent
 			generatedTaskRun, err := r.createTaskRun(ctx, svcAccount, strategy, build, buildRun)
 			if err != nil {
@@ -292,6 +301,22 @@ func (r *ReconcileBuildRun) Reconcile(ctx context.Context, request reconcile.Req
 				return reconcile.Result{}, err
 			}
 
+			err = resources.CheckTaskRunVolumesExist(ctx, r.client, generatedTaskRun)
+			// if resource is not found, fais the build run
+			if err != nil {
+				if apierrors.IsNotFound(err) {
+					if err := resources.UpdateConditionWithFalseStatus(ctx, r.client, buildRun, err.Error(), string(buildv1alpha1.VolumeDoesNotExist)); err != nil {
+						return reconcile.Result{}, err
+					}
+
+					// end of reconciliation
+					return reconcile.Result{}, nil
+				}
+
+				// some other error might have happened, return it and reconcile again
+				return reconcile.Result{}, err
+			}
+
 			ctxlog.Info(ctx, "creating TaskRun from BuildRun", namespace, request.Namespace, name, generatedTaskRun.GenerateName, "BuildRun", buildRun.Name)
 			if err = r.client.Create(ctx, generatedTaskRun); err != nil {
 				// system call failure, reconcile again