WIP: inflate steps from task

Signed-off-by: Hidde Beydals <[email protected]>

api/v1alpha1/promotion_types.go

@@ -1,6 +1,7 @@
 package v1alpha1
 
 import (
+	"fmt"
 	"time"
 
 	apiextensionsv1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
@@ -224,6 +225,16 @@ type PromotionStep struct {
 	Config *apiextensionsv1.JSON `json:"config,omitempty" protobuf:"bytes,3,opt,name=config"`
 }
 
+// GetAlias returns the As field, or a default value in the form of "step-{i}".
+// The provided index should be the index of the PromotionStep in the list of
+// PromotionSteps.
+func (s *PromotionStep) GetAlias(i int) string {
+	if s.As == "" {
+		return fmt.Sprintf("step-%d", i)
+	}
+	return s.As
+}
+
 // PromotionStatus describes the current state of the transition represented by
 // a Promotion.
 type PromotionStatus struct {

internal/kargo/kargo.go

@@ -2,11 +2,17 @@ package kargo
 
 import (
 	"context"
+	"encoding/json"
+	"errors"
 	"fmt"
+	"maps"
 	"strings"
 
 	"github.com/oklog/ulid/v2"
+	v1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/types"
+	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/event"
 	"sigs.k8s.io/controller-runtime/pkg/predicate"
 
@@ -26,9 +32,14 @@ const (
 // naming convention.
 func NewPromotion(
 	ctx context.Context,
+	client client.Client,
 	stage kargoapi.Stage,
 	freight string,
-) kargoapi.Promotion {
+) (*kargoapi.Promotion, error) {
+	if stage.Spec.PromotionTemplate == nil {
+		return nil, fmt.Errorf("Stage %q has no promotion template", stage.Name)
+	}
+
 	shortHash := freight
 	if len(shortHash) > 7 {
 		shortHash = freight[0:7]
@@ -57,13 +68,128 @@ func NewPromotion(
 		Spec: kargoapi.PromotionSpec{
 			Stage:   stage.Name,
 			Freight: freight,
+			Vars:   stage.Spec.PromotionTemplate.Spec.Vars,
 		},
 	}
-	if stage.Spec.PromotionTemplate != nil {
-		promotion.Spec.Vars = stage.Spec.PromotionTemplate.Spec.Vars
-		promotion.Spec.Steps = stage.Spec.PromotionTemplate.Spec.Steps
+
+	for i, step := range stage.Spec.PromotionTemplate.Spec.Steps {
+		switch {
+		case step.Task != nil:
+			alias := step.GetAlias(i)
+
+			taskSteps, err := inflatePromotionTaskSteps(ctx, client, stage.Namespace, alias, step)
+			if err != nil {
+				return nil, fmt.Errorf("failed to inflate steps for task %q (%q): %w", step.Task.Name, alias, err)
+			}
+
+			promotion.Spec.Steps = append(promotion.Spec.Steps, taskSteps...)
+		default:
+			promotion.Spec.Steps = append(promotion.Spec.Steps, step)
+		}
+	}
+
+	return &promotion, nil
+}
+
+func inflatePromotionTaskSteps(
+	ctx context.Context,
+	client client.Client,
+	project, taskAlias string,
+	taskStep kargoapi.PromotionStep,
+) ([]kargoapi.PromotionStep, error) {
+	if taskStep.Task == nil {
+		return nil, errors.New("taskStep has no task to inflate")
+	}
+
+	task, err := getPromotionTaskSpec(ctx, client, project, *taskStep.Task)
+	if err != nil {
+		return nil, err
+	}
+
+	inputs, err := composeInputsFromPromotionTaskConfig(task.Inputs, taskStep.Config)
+	if err != nil {
+		return nil, fmt.Errorf("failed to compose inputs from task config: %w", err)
+	}
+
+	var steps []kargoapi.PromotionStep
+	for _, step := range task.Steps {
+		stepInputs := make(map[string]string, len(inputs))
+		maps.Copy(stepInputs, inputs)
+
+		steps = append(steps, kargoapi.PromotionStep{
+			Uses:   taskStep.Uses,
+			As:     fmt.Sprintf("%s::%s", taskAlias, taskStep.Uses),
+			Retry:  taskStep.Retry.DeepCopy(),
+			Inputs: stepInputs,
+			Config: step.Config.DeepCopy(),
+		})
+	}
+	return steps, nil
+}
+
+func composeInputsFromPromotionTaskConfig(
+	inputs []kargoapi.PromotionTaskInput,
+	config *v1.JSON,
+) (map[string]string, error) {
+	if len(inputs) == 0 {
+		return nil, nil
+	}
+
+	cfg := make(map[string]any)
+	if err := json.Unmarshal(config.Raw, &cfg); err != nil {
+		return nil, fmt.Errorf("failed to unmarshal task config: %w", err)
+	}
+
+	m := make(map[string]string, len(inputs))
+	for _, input := range inputs {
+		if val, ok := cfg[input.Name]; ok {
+			strVal, strOk := val.(string)
+			if !strOk {
+				return nil, fmt.Errorf("input %q is not a string", input.Name)
+			}
+			m[input.Name] = strVal
+		} else if input.Default != "" {
+			m[input.Name] = input.Default
+		} else {
+			return nil, fmt.Errorf("missing required input %q", input.Name)
+		}
+	}
+
+	return m, nil
+}
+
+// getPromotionTaskSpec retrieves the PromotionTaskSpec for a given
+// PromotionTaskReference. The reference can be either a PromotionTask or a
+// ClusterPromotionTask.
+func getPromotionTaskSpec(
+	ctx context.Context,
+	client client.Client,
+	project string,
+	ref kargoapi.PromotionTaskReference,
+) (kargoapi.PromotionTaskSpec, error) {
+	var spec kargoapi.PromotionTaskSpec
+	switch ref.Kind {
+	case "PromotionTask", "":
+		task := &kargoapi.PromotionTask{}
+		if err := client.Get(ctx, types.NamespacedName{
+			Namespace: project,
+			Name:      ref.Name,
+		}, task); err != nil {
+			return spec, err
+		}
+		spec = task.Spec
+	case "ClusterPromotionTask":
+		task := &kargoapi.ClusterPromotionTask{}
+		if err := client.Get(ctx, types.NamespacedName{
+			Name: ref.Name,
+		}, task); err != nil {
+			return spec, err
+		}
+		spec = task.Spec
+	default:
+		return spec, fmt.Errorf("unknown task kind %q", ref.Kind)
 	}
-	return promotion
+	return spec, nil
 }
 
 func NewPromoWentTerminalPredicate(logger *logging.Logger) PromoWentTerminal[*kargoapi.Promotion] {