pkg/trait/prometheus.go

/*
Licensed to the Apache Software Foundation (ASF) under one or more
contributor license agreements.  See the NOTICE file distributed with
this work for additional information regarding copyright ownership.
The ASF licenses this file to You 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 trait

import (
	"fmt"
	"strconv"

	"github.com/apache/camel-k/pkg/apis/camel/v1alpha1"
	"github.com/apache/camel-k/pkg/util/envvar"

	corev1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/util/intstr"

	monitoringv1 "github.com/coreos/prometheus-operator/pkg/apis/monitoring/v1"
)

type prometheusTrait struct {
	BaseTrait `property:",squash"`

	Port                 int    `property:"port"`
	ServiceMonitor       bool   `property:"service-monitor"`
	ServiceMonitorLabels string `property:"service-monitor-labels"`
}

const prometheusPortName = "prometheus"

// The Prometheus trait must be executed prior to the deployment trait
// as it mutates environment variables
func newPrometheusTrait() *prometheusTrait {
	return &prometheusTrait{
		BaseTrait:      newBaseTrait("prometheus"),
		Port:           9779,
		ServiceMonitor: true,
	}
}

func (t *prometheusTrait) Configure(e *Environment) (bool, error) {
	return e.IntegrationInPhase(v1alpha1.IntegrationPhaseDeploying), nil
}

func (t *prometheusTrait) Apply(e *Environment) (err error) {
	containerName := defaultContainerName
	dt := e.Catalog.GetTrait(containerTraitID)
	if dt != nil {
		containerName = dt.(*containerTrait).Name
	}

	container := e.Resources.GetContainerByName(containerName)
	if container == nil {
		e.Integration.Status.SetCondition(
			v1alpha1.IntegrationConditionPrometheusAvailable,
			corev1.ConditionFalse,
			v1alpha1.IntegrationConditionContainerNotAvailableReason,
			"",
		)
		return nil
	}

	if t.Enabled == nil || !*t.Enabled {
		// Deactivate the Prometheus Java agent
		// Note: the AB_PROMETHEUS_OFF environment variable acts as an option flag
		envvar.SetVal(&container.Env, "AB_PROMETHEUS_OFF", "true")
		return nil
	}

	condition := v1alpha1.IntegrationCondition{
		Type:   v1alpha1.IntegrationConditionPrometheusAvailable,
		Status: corev1.ConditionTrue,
		Reason: v1alpha1.IntegrationConditionPrometheusAvailableReason,
	}

	// Configure the Prometheus Java agent
	envvar.SetVal(&container.Env, "AB_PROMETHEUS_PORT", strconv.Itoa(t.Port))

	// Add the container port
	containerPort := t.getContainerPort()
	container.Ports = append(container.Ports, *containerPort)
	condition.Message = fmt.Sprintf("%s(%s/%d)", container.Name, containerPort.Name, containerPort.ContainerPort)

	// Retrieve the service or create a new one if the service trait is enabled
	serviceEnabled := false
	service := e.Resources.GetServiceForIntegration(e.Integration)
	if service == nil {
		trait := e.Catalog.GetTrait(serviceTraitID)
		if serviceTrait, ok := trait.(*serviceTrait); ok {
			serviceEnabled = serviceTrait.isEnabled()
		}
		if serviceEnabled {
			// add a new service if not already created
			service = getServiceFor(e)
			e.Resources.Add(service)
		}
	}

	// Add the service port and service monitor resource
	// A better strategy may be needed when the Knative profile is active
	if serviceEnabled {
		servicePort := t.getServicePort()
		service.Spec.Ports = append(service.Spec.Ports, *servicePort)
		condition.Message = fmt.Sprintf("%s(%s/%d) -> ", service.Name, servicePort.Name, servicePort.Port) + condition.Message

		// Add the ServiceMonitor resource
		if t.ServiceMonitor {
			smt, err := t.getServiceMonitorFor(e)
			if err != nil {
				return err
			}
			e.Resources.Add(smt)
		}
	} else {
		condition.Status = corev1.ConditionFalse
		condition.Reason = v1alpha1.IntegrationConditionServiceNotAvailableReason
	}

	e.Integration.Status.SetConditions(condition)

	return nil
}

func (t *prometheusTrait) getContainerPort() *corev1.ContainerPort {
	containerPort := corev1.ContainerPort{
		Name:          prometheusPortName,
		ContainerPort: int32(t.Port),
		Protocol:      corev1.ProtocolTCP,
	}
	return &containerPort
}

func (t *prometheusTrait) getServicePort() *corev1.ServicePort {
	servicePort := corev1.ServicePort{
		Name:       prometheusPortName,
		Port:       int32(t.Port),
		Protocol:   corev1.ProtocolTCP,
		TargetPort: intstr.FromString(prometheusPortName),
	}
	return &servicePort
}

func (t *prometheusTrait) getServiceMonitorFor(e *Environment) (*monitoringv1.ServiceMonitor, error) {
	labels, err := parseCsvMap(&t.ServiceMonitorLabels)
	if err != nil {
		return nil, err
	}
	labels["camel.apache.org/integration"] = e.Integration.Name

	smt := monitoringv1.ServiceMonitor{
		TypeMeta: metav1.TypeMeta{
			Kind:       "ServiceMonitor",
			APIVersion: "monitoring.coreos.com/v1",
		},
		ObjectMeta: metav1.ObjectMeta{
			Name:      e.Integration.Name,
			Namespace: e.Integration.Namespace,
			Labels:    labels,
		},
		Spec: monitoringv1.ServiceMonitorSpec{
			Selector: metav1.LabelSelector{
				MatchLabels: map[string]string{
					"camel.apache.org/integration": e.Integration.Name,
				},
			},
			Endpoints: []monitoringv1.Endpoint{
				{
					Port: prometheusPortName,
				},
			},
		},
	}
	return &smt, nil
}