localenv/services/service.go

package services

import (
	"context"
	"errors"
	"fmt"
	"time"

	"localenv/utils"

	"github.com/docker/docker/api/types/swarm"
	"github.com/docker/docker/client"
)

const NetworkName = "localenv"

var (
	RetryServiceAttempts uint64 = 0
	SwarmServiceReplicas uint64 = 1

	RetryServiceDelay = 20 * time.Second

	ErrNoRunningContainer = errors.New("no running container")
)

type ServiceOption func(spec *swarm.ServiceSpec)

func WithIONetwork() ServiceOption {
	return WithNetwork(NetworkName)
}

func WithNetwork(name string) ServiceOption {
	return func(spec *swarm.ServiceSpec) {
		spec.Networks = append(spec.Networks,
			swarm.NetworkAttachmentConfig{
				Target:  name,
				Aliases: []string{name},
			},
		)
	}
}

func WithHostEndpoint(port uint32) ServiceOption {
	return func(spec *swarm.ServiceSpec) {
		spec.EndpointSpec = &swarm.EndpointSpec{
			Mode: "vip",
			Ports: []swarm.PortConfig{
				{
					Protocol:      "tcp",
					TargetPort:    port,
					PublishedPort: port,
					PublishMode:   "host",
				},
			},
		}
	}
}

func WithRestartPolicy() ServiceOption {
	return func(spec *swarm.ServiceSpec) {
		spec.TaskTemplate.RestartPolicy = &swarm.RestartPolicy{
			Condition:   swarm.RestartPolicyConditionOnFailure,
			MaxAttempts: &RetryServiceAttempts,
			Delay:       &RetryServiceDelay,
		}
	}
}

func WithPostgres(name string) ServiceOption {
	return func(spec *swarm.ServiceSpec) {
		if spec.TaskTemplate.ContainerSpec == nil {
			return
		}

		spec.TaskTemplate.ContainerSpec.Env = append(
			spec.TaskTemplate.ContainerSpec.Env,
			"DB_TYPE=postgres",
			fmt.Sprintf("POSTGRES_HOSTNAME=pg-%s", name),
			fmt.Sprintf("POSTGRES_PORT=%d", PostgresServicePort),
			fmt.Sprintf("POSTGRES_DB=%s", name),
			"POSTGRES_USER=test",
			"POSTGRES_PASSWORD=test",
		)
	}
}

func WithRabbitMQ() ServiceOption {
	return func(spec *swarm.ServiceSpec) {
		if spec.TaskTemplate.ContainerSpec == nil {
			return
		}

		spec.TaskTemplate.ContainerSpec.Env = append(
			spec.TaskTemplate.ContainerSpec.Env,
			fmt.Sprintf("RABBITMQ_ENDPOINT=amqp://%s:%d", RabbitMQServiceName, RabbitMQServicePort),
			"RABBITMQ_USERNAME=intercloud",
			"RABBITMQ_PASSWORD=intercloud",
		)
	}
}

type Servicer interface {
	Deploy(ctx context.Context, cli *client.Client) error
}

type Service struct {
	spec swarm.ServiceSpec
	name string
}

func (p *Service) GetBaseServiceSpec(serviceName, hostname, imageName, port string, command []string) swarm.ServiceSpec {
	spec := swarm.ServiceSpec{
		Annotations: swarm.Annotations{
			Name: serviceName,
		},
		TaskTemplate: swarm.TaskSpec{
			ContainerSpec: &swarm.ContainerSpec{
				Hostname: hostname,
				Image:    imageName,
				Env: []string{
					fmt.Sprintf("PORT=%s", port),
				},
				Command: command,
			},
		},
		Mode: swarm.ServiceMode{
			Replicated: &swarm.ReplicatedService{
				Replicas: &SwarmServiceReplicas,
			},
		},
	}

	return spec
}

func Deploy(ctx context.Context, cli *client.Client, spec *swarm.ServiceSpec, dependencies []Servicer) error {
	err := utils.CheckServiceHealth(ctx, cli, spec.Annotations.Name)
	if err == nil {
		return nil
	}

	if !errors.Is(err, utils.ErrServiceNotFound) {
		return err
	}

	for _, deps := range dependencies {
		if err := deps.Deploy(ctx, cli); err != nil {
			return err
		}
	}

	if err := utils.CreateService(ctx, cli, spec); err != nil {
		return err
	}

	return nil
}