applicationhealthdeployment_controller.go

/*
Copyright 2021.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package controller

import (
	"context"
	"slices"
	"time"

	argocdv1alpha1 "github.com/argoproj/argo-cd/v2/pkg/apis/application/v1alpha1"
	synccommon "github.com/argoproj/gitops-engine/pkg/sync/common"
	"github.com/int128/argocd-commenter/internal/argocd"
	"github.com/int128/argocd-commenter/internal/controller/eventfilter"
	"github.com/int128/argocd-commenter/internal/notification"
	corev1 "k8s.io/api/core/v1"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/client-go/tools/record"
	ctrl "sigs.k8s.io/controller-runtime"
	"sigs.k8s.io/controller-runtime/pkg/client"
	"sigs.k8s.io/controller-runtime/pkg/log"
)

var (
	// When the GitHub Deployment is not found, this action will retry by this interval
	// until the application is synced with a valid GitHub Deployment.
	// This should be reasonable to avoid the rate limit of GitHub API.
	requeueIntervalWhenDeploymentNotFound = 30 * time.Second

	// When the GitHub Deployment is not found, this action will retry by this timeout.
	// Argo CD refreshes an application every 3 minutes by default.
	// This should be reasonable to avoid the rate limit of GitHub API.
	requeueTimeoutWhenDeploymentNotFound = 10 * time.Minute
)

// ApplicationHealthDeploymentReconciler reconciles an Application object.
// It creates a deployment status when the health status is changed.
type ApplicationHealthDeploymentReconciler struct {
	client.Client
	Scheme       *runtime.Scheme
	Recorder     record.EventRecorder
	Notification notification.Client
}

//+kubebuilder:rbac:groups=argoproj.io,resources=applications,verbs=get;watch;list
//+kubebuilder:rbac:groups=core,resources=configmaps,verbs=get;watch;list
//+kubebuilder:rbac:groups=core,resources=events,verbs=create;patch
//+kubebuilder:rbac:groups=argocdcommenter.int128.github.io,resources=applicationhealths,verbs=get;list;watch;create;update;patch
//+kubebuilder:rbac:groups=argocdcommenter.int128.github.io,resources=applicationhealths/status,verbs=get;update;patch

func (r *ApplicationHealthDeploymentReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
	logger := log.FromContext(ctx)

	var app argocdv1alpha1.Application
	if err := r.Get(ctx, req.NamespacedName, &app); err != nil {
		return ctrl.Result{}, client.IgnoreNotFound(err)
	}
	if !app.DeletionTimestamp.IsZero() {
		return ctrl.Result{}, nil
	}
	deploymentURL := argocd.GetDeploymentURL(app)
	if deploymentURL == "" {
		return ctrl.Result{}, nil
	}

	deploymentIsAlreadyHealthy, err := r.Notification.CheckIfDeploymentIsAlreadyHealthy(ctx, deploymentURL)
	if notification.IsNotFoundError(err) {
		// Retry until the application is synced with a valid GitHub Deployment.
		// https://github.com/int128/argocd-commenter/issues/762
		lastOperationAt := argocd.GetLastOperationAt(app).Time
		if time.Since(lastOperationAt) < requeueTimeoutWhenDeploymentNotFound {
			r.Recorder.Eventf(&app, corev1.EventTypeNormal, "DeploymentNotFound",
				"deployment %s not found, retry after %s", deploymentURL, requeueIntervalWhenDeploymentNotFound)
			return ctrl.Result{RequeueAfter: requeueIntervalWhenDeploymentNotFound}, nil
		}
		r.Recorder.Eventf(&app, corev1.EventTypeWarning, "DeploymentNotFoundRetryTimeout",
			"deployment %s not found but retry timed out", deploymentURL)
		return ctrl.Result{}, nil
	}
	if deploymentIsAlreadyHealthy {
		r.Recorder.Eventf(&app, corev1.EventTypeNormal, "DeploymentAlreadyHealthy",
			"skip on status %s because deployment %s is already healthy", app.Status.Health.Status, deploymentURL)
		return ctrl.Result{}, nil
	}

	// Evaluate the health status only if the sync operation is succeeded.
	phase := argocd.GetSyncOperationPhase(app)
	if phase != synccommon.OperationSucceeded {
		return ctrl.Result{}, nil
	}
	syncOperationFinishedAt := argocd.GetSyncOperationFinishedAt(app)
	if syncOperationFinishedAt == nil {
		return ctrl.Result{}, nil
	}

	// If this controller is run just after the sync operation,
	// it will evaluate the health status after a few seconds.
	// https://github.com/int128/argocd-commenter/issues/1044
	if time.Since(syncOperationFinishedAt.Time) < requeueTimeToEvaluateHealthStatusAfterSyncOperation {
		logger.Info("Requeue later to evaluate the health status", "after", requeueTimeToEvaluateHealthStatusAfterSyncOperation,
			"syncOperationFinishedAt", syncOperationFinishedAt)
		return ctrl.Result{RequeueAfter: requeueTimeToEvaluateHealthStatusAfterSyncOperation}, nil
	}

	argocdURL, err := argocd.GetExternalURL(ctx, r.Client, req.Namespace)
	if err != nil {
		logger.Info("unable to determine Argo CD URL", "error", err)
	}

	if err := r.Notification.CreateDeploymentStatusOnHealthChanged(ctx, app, argocdURL); err != nil {
		r.Recorder.Eventf(&app, corev1.EventTypeWarning, "CreateDeploymentStatusError",
			"unable to create a deployment status on health status %s: %s", app.Status.Health.Status, err)
	} else {
		r.Recorder.Eventf(&app, corev1.EventTypeNormal, "CreatedDeploymentStatus",
			"created a deployment status on health status %s", app.Status.Health.Status)
	}
	return ctrl.Result{}, nil
}

// SetupWithManager sets up the controller with the Manager.
func (r *ApplicationHealthDeploymentReconciler) SetupWithManager(mgr ctrl.Manager) error {
	r.Recorder = mgr.GetEventRecorderFor("application-health-deployment")
	return ctrl.NewControllerManagedBy(mgr).
		Named("applicationHealthDeployment").
		For(&argocdv1alpha1.Application{}).
		WithEventFilter(eventfilter.ApplicationChanged(filterApplicationHealthStatusForDeploymentStatus)).
		Complete(r)
}

func filterApplicationHealthStatusForDeploymentStatus(appOld, appNew argocdv1alpha1.Application) bool {
	if argocd.GetDeploymentURL(appNew) == "" {
		return false
	}

	// When the health status is changed
	healthOld, healthNew := appOld.Status.Health.Status, appNew.Status.Health.Status
	if healthOld != healthNew && slices.Contains(notification.HealthStatusesForDeploymentStatus, healthNew) {
		return true
	}

	// When an application is synced but the health status is not changed,
	// the controller will evaluate the health status after sync.
	phaseOld, phaseNew := argocd.GetSyncOperationPhase(appOld), argocd.GetSyncOperationPhase(appNew)
	if phaseOld != phaseNew && phaseNew == synccommon.OperationSucceeded {
		return true
	}

	return false
}