builder.go

// Copyright The OpenTelemetry Authors
//
// 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 components

import (
	"fmt"

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

	"github.com/open-telemetry/opentelemetry-operator/internal/naming"
)

type ParserOption[ComponentConfigType any] func(*Settings[ComponentConfigType])

type Settings[ComponentConfigType any] struct {
	protocol     corev1.Protocol
	appProtocol  *string
	targetPort   intstr.IntOrString
	nodePort     int32
	name         string
	port         int32
	portParser   PortParser[ComponentConfigType]
	rbacGen      RBACRuleGenerator[ComponentConfigType]
	livenessGen  ProbeGenerator[ComponentConfigType]
	readinessGen ProbeGenerator[ComponentConfigType]
}

func NewEmptySettings[ComponentConfigType any]() *Settings[ComponentConfigType] {
	return &Settings[ComponentConfigType]{}
}

func (o *Settings[ComponentConfigType]) Apply(opts ...ParserOption[ComponentConfigType]) {
	for _, opt := range opts {
		opt(o)
	}
}

func (o *Settings[ComponentConfigType]) GetServicePort() *corev1.ServicePort {
	return &corev1.ServicePort{
		Name:        naming.PortName(o.name, o.port),
		Port:        o.port,
		Protocol:    o.protocol,
		AppProtocol: o.appProtocol,
		TargetPort:  o.targetPort,
		NodePort:    o.nodePort,
	}
}

type Builder[ComponentConfigType any] []ParserOption[ComponentConfigType]

func NewBuilder[ComponentConfigType any]() Builder[ComponentConfigType] {
	return []ParserOption[ComponentConfigType]{}
}

func (b Builder[ComponentConfigType]) WithProtocol(protocol corev1.Protocol) Builder[ComponentConfigType] {
	return append(b, func(o *Settings[ComponentConfigType]) {
		o.protocol = protocol
	})
}
func (b Builder[ComponentConfigType]) WithAppProtocol(appProtocol *string) Builder[ComponentConfigType] {
	return append(b, func(o *Settings[ComponentConfigType]) {
		o.appProtocol = appProtocol
	})
}
func (b Builder[ComponentConfigType]) WithTargetPort(targetPort int32) Builder[ComponentConfigType] {
	return append(b, func(o *Settings[ComponentConfigType]) {
		o.targetPort = intstr.FromInt32(targetPort)
	})
}
func (b Builder[ComponentConfigType]) WithNodePort(nodePort int32) Builder[ComponentConfigType] {
	return append(b, func(o *Settings[ComponentConfigType]) {
		o.nodePort = nodePort
	})
}
func (b Builder[ComponentConfigType]) WithName(name string) Builder[ComponentConfigType] {
	return append(b, func(o *Settings[ComponentConfigType]) {
		o.name = name
	})
}
func (b Builder[ComponentConfigType]) WithPort(port int32) Builder[ComponentConfigType] {
	return append(b, func(o *Settings[ComponentConfigType]) {
		o.port = port
	})
}
func (b Builder[ComponentConfigType]) WithPortParser(portParser PortParser[ComponentConfigType]) Builder[ComponentConfigType] {
	return append(b, func(o *Settings[ComponentConfigType]) {
		o.portParser = portParser
	})
}
func (b Builder[ComponentConfigType]) WithRbacGen(rbacGen RBACRuleGenerator[ComponentConfigType]) Builder[ComponentConfigType] {
	return append(b, func(o *Settings[ComponentConfigType]) {
		o.rbacGen = rbacGen
	})
}

func (b Builder[ComponentConfigType]) WithLivenessGen(livenessGen ProbeGenerator[ComponentConfigType]) Builder[ComponentConfigType] {
	return append(b, func(o *Settings[ComponentConfigType]) {
		o.livenessGen = livenessGen
	})
}

func (b Builder[ComponentConfigType]) WithReadinessGen(readinessGen ProbeGenerator[ComponentConfigType]) Builder[ComponentConfigType] {
	return append(b, func(o *Settings[ComponentConfigType]) {
		o.readinessGen = readinessGen
	})
}

func (b Builder[ComponentConfigType]) Build() (*GenericParser[ComponentConfigType], error) {
	o := NewEmptySettings[ComponentConfigType]()
	o.Apply(b...)
	if len(o.name) == 0 {
		return nil, fmt.Errorf("invalid settings struct, no name specified")
	}
	return &GenericParser[ComponentConfigType]{
		name:         o.name,
		portParser:   o.portParser,
		rbacGen:      o.rbacGen,
		livenessGen:  o.livenessGen,
		readinessGen: o.readinessGen,
		settings:     o,
	}, nil
}

func (b Builder[ComponentConfigType]) MustBuild() *GenericParser[ComponentConfigType] {
	if p, err := b.Build(); err != nil {
		panic(err)
	} else {
		return p
	}
}