From e6d3458faec9e2a806fa2876eb39053a1d4d1c83 Mon Sep 17 00:00:00 2001
From: Hidde Beydals <hidde@hhh.computer>
Date: Tue, 17 Sep 2024 15:58:03 +0200
Subject: [PATCH] feat: wire directives into promotion reconciler

Signed-off-by: Hidde Beydals <hidde@hhh.computer>
---
 api/v1alpha1/promotion_types.go              | 14 ++++++
 internal/controller/promotions/promotions.go | 50 ++++++++++++++++----
 2 files changed, 55 insertions(+), 9 deletions(-)

diff --git a/api/v1alpha1/promotion_types.go b/api/v1alpha1/promotion_types.go
index 69ae3fe07..54ef216de 100644
--- a/api/v1alpha1/promotion_types.go
+++ b/api/v1alpha1/promotion_types.go
@@ -3,6 +3,7 @@ package v1alpha1
 import (
 	apiextensionsv1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"sigs.k8s.io/yaml"
 )
 
 type PromotionPhase string
@@ -100,6 +101,19 @@ type PromotionStep struct {
 	Config *apiextensionsv1.JSON `json:"config,omitempty" protobuf:"bytes,3,opt,name=config"`
 }
 
+// GetConfig returns the Config field as unmarshalled YAML.
+func (s *PromotionStep) GetConfig() map[string]any {
+	if s.Config == nil {
+		return nil
+	}
+
+	var config map[string]any
+	if err := yaml.Unmarshal(s.Config.Raw, &config); err != nil {
+		return nil
+	}
+	return config
+}
+
 // PromotionStatus describes the current state of the transition represented by
 // a Promotion.
 type PromotionStatus struct {
diff --git a/internal/controller/promotions/promotions.go b/internal/controller/promotions/promotions.go
index b79ccb201..01e83736a 100644
--- a/internal/controller/promotions/promotions.go
+++ b/internal/controller/promotions/promotions.go
@@ -26,6 +26,7 @@ import (
 	"github.com/akuity/kargo/internal/controller/promotion"
 	"github.com/akuity/kargo/internal/controller/runtime"
 	"github.com/akuity/kargo/internal/credentials"
+	"github.com/akuity/kargo/internal/directives"
 	"github.com/akuity/kargo/internal/kargo"
 	"github.com/akuity/kargo/internal/kubeclient"
 	libEvent "github.com/akuity/kargo/internal/kubernetes/event"
@@ -53,8 +54,9 @@ func ReconcilerConfigFromEnv() ReconcilerConfig {
 
 // reconciler reconciles Promotion resources.
 type reconciler struct {
-	kargoClient     client.Client
-	promoMechanisms promotion.Mechanism
+	kargoClient      client.Client
+	directivesEngine *directives.Engine
+	promoMechanisms  promotion.Mechanism
 
 	cfg ReconcilerConfig
 
@@ -186,9 +188,15 @@ func newReconciler(
 	}
 	r := &reconciler{
 		kargoClient: kargoClient,
-		recorder:    recorder,
-		cfg:         cfg,
-		pqs:         &pqs,
+		directivesEngine: directives.NewEngine(
+			directives.BuiltinsRegistry(),
+			credentialsDB,
+			kargoClient,
+			argocdClient,
+		),
+		recorder: recorder,
+		cfg:      cfg,
+		pqs:      &pqs,
 		promoMechanisms: promotion.NewMechanisms(
 			kargoClient,
 			argocdClient,
@@ -497,11 +505,35 @@ func (r *reconciler) promote(
 		stage,
 	)
 
-	if err := r.promoMechanisms.Promote(ctx, stage, workingPromo); err != nil {
-		return nil, err
-	}
+	if workingPromo.Spec.Steps == nil {
+		// If the Promotion has no steps, assume we are dealing with "legacy"
+		// Promotion mechanisms.
+		if err := r.promoMechanisms.Promote(ctx, stage, workingPromo); err != nil {
+			return nil, err
+		}
 
-	logger.Debug("promotion", "phase", workingPromo.Status.Phase)
+		logger.Debug("promotion", "phase", workingPromo.Status.Phase)
+	} else {
+		// If the Promotion has steps, execute them in sequence.
+		var steps []directives.Step
+		for _, step := range workingPromo.Spec.Steps {
+			steps = append(steps, directives.Step{
+				Directive: step.Step,
+				Alias:     step.As,
+				Config:    step.GetConfig(),
+			})
+		}
+		status, err := r.directivesEngine.Execute(ctx, steps)
+		switch status {
+		case directives.StatusSuccess:
+			workingPromo.Status.Phase = kargoapi.PromotionPhaseSucceeded
+		case directives.StatusFailure:
+			workingPromo.Status.Phase = kargoapi.PromotionPhaseFailed
+		}
+		if err != nil {
+			return nil, err
+		}
+	}
 
 	if workingPromo.Status.Phase == kargoapi.PromotionPhaseSucceeded {
 		// Trigger re-verification of the Stage if the promotion succeeded and