generator/crontabs.go

@@ -0,0 +1,84 @@
+package generator
+
+import (
+	"fmt"
+	"katenary/helm"
+	"log"
+
+	"github.com/compose-spec/compose-go/types"
+	"gopkg.in/yaml.v3"
+)
+
+const (
+	cronMulti    = `pods=$(kubectl get pods --selector=%s/component=%s,%s/resource=deployment -o jsonpath='{.items[*].metadata.name}')`
+	cronMultiCmd = `
+for pod in $pods; do
+    kubectl exec -i $pod -c %s -- sh -c '%s'
+done`
+	cronSingle = `pod=$(kubectl get pods --selector=%s/component=%s,%s/resource=deployment -o jsonpath='{.items[0].metadata.name}')`
+	cronCmd    = `
+kubectl exec -i $pod -c %s -- sh -c '%s'`
+)
+
+type CronDef struct {
+	Command  string `yaml:"command"`
+	Schedule string `yaml:"schedule"`
+	Multi    bool   `yaml:"allPods,omitempty"`
+}
+
+func buildCrontab(deployName string, deployment *helm.Deployment, s *types.ServiceConfig, fileGeneratorChan HelmFileGenerator) {
+	// get the cron label from the service
+	var crondef string
+	var ok bool
+	if crondef, ok = s.Labels[helm.LABEL_CRON]; !ok {
+		return
+	}
+
+	// parse yaml
+	crons := []CronDef{}
+	err := yaml.Unmarshal([]byte(crondef), &crons)
+	if err != nil {
+		log.Fatalf("error: %v", err)
+	}
+	log.Println(crons)
+
+	// create a serviceAccount
+	sa := helm.NewServiceAccount(deployName)
+	// create a role
+	role := helm.NewCronRole(deployName)
+
+	// create a roleBinding
+	roleBinding := helm.NewRoleBinding(deployName, sa, role)
+
+	// make generation
+	fileGeneratorChan <- sa
+	fileGeneratorChan <- role
+	fileGeneratorChan <- roleBinding
+
+	// create crontabs
+	for _, cron := range crons {
+		var cmd, podget string
+		if cron.Multi {
+			podget = cronMulti
+			cmd = cronMultiCmd
+		} else {
+			podget = cronSingle
+			cmd = cronCmd
+		}
+		podget = fmt.Sprintf(podget, helm.K, deployName, helm.K)
+		cmd = fmt.Sprintf(cmd, s.Name, cron.Command)
+		cmd = podget + cmd
+
+		cronTab := helm.NewCrontab(
+			deployName,
+			"bitnami/kubectl",
+			cmd,
+			cron.Schedule,
+			sa,
+		)
+		// add crontab
+		fileGeneratorChan <- cronTab
+	}
+
+	return
+}

generator/main.go

@@ -788,7 +788,14 @@ func setSecretVar(name string, s *types.ServiceConfig, c *helm.Container) *helm.
 
 // Generate a container in deployment with all needed objects (volumes, secrets, env, ...).
 // The deployName shoud be the name of the deployment, we cannot get it from Metadata as this is a variable name.
-func newContainerForDeployment(deployName, containerName string, deployment *helm.Deployment, s *types.ServiceConfig, fileGeneratorChan HelmFileGenerator) *helm.Container {
+func newContainerForDeployment(
+	deployName, containerName string,
+	deployment *helm.Deployment,
+	s *types.ServiceConfig,
+	fileGeneratorChan HelmFileGenerator) *helm.Container {
+
+	buildCrontab(deployName, deployment, s, fileGeneratorChan)
+
 	container := helm.NewContainer(containerName, s.Image, s.Environment, s.Labels)
 
 	applyEnvMapLabel(s, container)

helm/cronTab.go

@@ -0,0 +1,60 @@
+package helm
+
+type Job struct {
+	ServiceAccount     string      `yaml:"serviceAccount,omitempty"`
+	ServiceAccountName string      `yaml:"serviceAccountName,omitempty"`
+	Containers         []Container `yaml:"containers"`
+	RestartPolicy      string      `yaml:"restartPolicy,omitempty"`
+}
+type JobSpec struct {
+	Template Job `yaml:"template"`
+}
+
+type JobTemplate struct {
+	Metadata Metadata `yaml:"metadata"`
+	Spec     JobSpec  `yaml:"spec"`
+	Schedule string   `yaml:"schedule"`
+}
+
+type CronTab struct {
+	*K8sBase    `yaml:",inline"`
+	JobTemplate JobTemplate `yaml:"jobTemplate"`
+}
+
+func NewCrontab(name, image, command, schedule string, serviceAccount *ServiceAccount) *CronTab {
+	cron := &CronTab{
+		K8sBase: NewBase(),
+	}
+	cron.K8sBase.ApiVersion = "batch/v1"
+	cron.K8sBase.Kind = "CronJob"
+
+	//cmd, err := shlex.Split(command)
+	//if err != nil {
+	//	panic(err)
+	//}
+
+	cron.K8sBase.Metadata.Name = ReleaseNameTpl + "-" + name
+	cron.K8sBase.Metadata.Labels[K+"/component"] = name
+	cron.JobTemplate = JobTemplate{
+		Schedule: schedule,
+		Metadata: Metadata{
+			Labels: cron.K8sBase.Metadata.Labels,
+		},
+		Spec: JobSpec{
+			Template: Job{
+				ServiceAccount:     serviceAccount.Name(),
+				ServiceAccountName: serviceAccount.Name(),
+				Containers: []Container{
+					{
+						Name:    name,
+						Image:   image,
+						Command: []string{command},
+					},
+				},
+				RestartPolicy: "OnFailure",
+			},
+		},
+	}
+
+	return cron
+}

helm/deployment.go

@@ -12,6 +12,7 @@ func NewDeployment(name string) *Deployment {
 	d.K8sBase.ApiVersion = "apps/v1"
 	d.K8sBase.Kind = "Deployment"
 	d.K8sBase.Metadata.Labels[K+"/component"] = name
+	d.K8sBase.Metadata.Labels[K+"/resource"] = "deployment"
 	return d
 }
 

helm/labels.go

@@ -18,6 +18,7 @@ const (
 	LABEL_EMPTYDIRS   = K + "/empty-dirs"
 	LABEL_IGNORE      = K + "/ignore"
 	LABEL_SECRETVARS  = K + "/secret-vars"
+	LABEL_CRON        = K + "/crontabs"
 
 	//deprecated: use LABEL_MAP_ENV instead
 	LABEL_ENV_SERVICE = K + "/env-to-service"
@@ -37,6 +38,7 @@ func GetLabelsDocumentation() string {
 {{.LABEL_SAMEPOD     | printf "%-33s"}}: specifies that the pod should be deployed in the same pod than the given service name
 {{.LABEL_VOLUMEFROM  | printf "%-33s"}}: specifies that the volumes to be mounted from the given service (yaml style)
 {{.LABEL_EMPTYDIRS   | printf "%-33s"}}: specifies that the given volume names should be "emptyDir" instead of persistentVolumeClaim (coma separated)
+{{.LABEL_CRON        | printf "%-33s"}}: specifies that the given cronjobs should be deployed (yaml style, array)
 {{.LABEL_HEALTHCHECK | printf "%-33s"}}: specifies that the container should be monitored by a healthcheck, **it overrides the docker-compose healthcheck**. 
 {{ printf "%-34s" ""}} You can use these form of label values:
 {{ printf "%-35s" ""}}- "http://[not used address][:port][/path]" to specify an http healthcheck
@@ -56,6 +58,7 @@ func GetLabelsDocumentation() string {
 		"LABEL_IGNORE":      LABEL_IGNORE,
 		"LABEL_MAP_ENV":     LABEL_MAP_ENV,
 		"LABEL_SECRETVARS":  LABEL_SECRETVARS,
+		"LABEL_CRON":        LABEL_CRON,
 	})
 	return buff.String()
 }

helm/role.go

@@ -0,0 +1,33 @@
+package helm
+
+type Rule struct {
+	ApiGroup  []string `yaml:"apiGroup,omitempty"`
+	Resources []string `yaml:"resource,omitempty"`
+	Verbs     []string `yaml:"verbs,omitempty"`
+}
+
+type Role struct {
+	*K8sBase `yaml:",inline"`
+	Rules    []Rule `yaml:"rules,omitempty"`
+}
+
+func NewCronRole(name string) *Role {
+	role := &Role{
+		K8sBase: NewBase(),
+	}
+
+	role.K8sBase.Metadata.Name = ReleaseNameTpl + "-" + name + "-cron-executor"
+	role.K8sBase.Kind = "Role"
+	role.K8sBase.ApiVersion = "rbac.authorization.k8s.io/v1"
+	role.K8sBase.Metadata.Labels[K+"/component"] = name
+
+	role.Rules = []Rule{
+		{
+			ApiGroup:  []string{""},
+			Resources: []string{"pods", "pods/exec"},
+			Verbs:     []string{"get", "list", "create"},
+		},
+	}
+
+	return role
+}

helm/roleBinding.go

@@ -0,0 +1,44 @@
+package helm
+
+type RoleRef struct {
+	Kind     string `yaml:"kind"`
+	Name     string `yaml:"name"`
+	APIGroup string `yaml:"apiGroup"`
+}
+
+type Subject struct {
+	Kind      string `yaml:"kind"`
+	Name      string `yaml:"name"`
+	Namespace string `yaml:"namespace"`
+}
+
+type RoleBinding struct {
+	*K8sBase `yaml:",inline"`
+	RoleRef  RoleRef   `yaml:"roleRef,omitempty"`
+	Subjects []Subject `yaml:"subjects,omitempty"`
+}
+
+func NewRoleBinding(name string, user *ServiceAccount, role *Role) *RoleBinding {
+	rb := &RoleBinding{
+		K8sBase: NewBase(),
+	}
+
+	rb.K8sBase.Kind = "RoleBinding"
+	rb.K8sBase.Metadata.Name = ReleaseNameTpl + "-" + name + "-cron-allow"
+	rb.K8sBase.ApiVersion = "rbac.authorization.k8s.io/v1"
+	rb.K8sBase.Metadata.Labels[K+"/component"] = name
+
+	rb.RoleRef.Kind = "Role"
+	rb.RoleRef.Name = role.Metadata.Name
+	rb.RoleRef.APIGroup = "rbac.authorization.k8s.io"
+
+	rb.Subjects = []Subject{
+		{
+			Kind:      "ServiceAccount",
+			Name:      user.Metadata.Name,
+			Namespace: "{{ .Release.Namespace }}",
+		},
+	}
+
+	return rb
+}

helm/serviceAccount.go

@@ -0,0 +1,18 @@
+package helm
+
+// ServiceAccount defines a service account
+type ServiceAccount struct {
+	*K8sBase `yaml:",inline"`
+}
+
+// NewServiceAccount creates a new service account with a given name.
+func NewServiceAccount(name string) *ServiceAccount {
+	sa := &ServiceAccount{
+		K8sBase: NewBase(),
+	}
+	sa.K8sBase.Kind = "ServiceAccount"
+	sa.K8sBase.ApiVersion = "v1"
+	sa.K8sBase.Metadata.Name = ReleaseNameTpl + "-" + name + "-cron-user"
+	sa.K8sBase.Metadata.Labels[K+"/component"] = name
+	return sa
+}