Merge pull request #11 from cd1989/cron-trigger

Cron trigger

Gopkg.toml

@@ -14,6 +14,10 @@
   name = "github.com/stretchr/testify"
   version = "1.2.2"
 
+[[constraint]]
+  name = "github.com/robfig/cron"
+  version = "v3.0.0"
+
 [prune]
   go-tests = true
   unused-packages = true

README.md

@@ -7,6 +7,7 @@ Clean images in Harbor by policies.
 - **Delete tags without side effects** As we known when we delete a tag from a repo in docker registry, the underneath manifest is deleted, so are other tags what share the same manifest. In this tool, we protect tags from such situation.
 - **Delete by policies** Support delete tags by configurable policies
 - **Dry run before actual cleanup** To see what would be cleaned up before performing real cleanup.
+- **Cron Schedule** Schedule the cleanup regularly by cron.
 
 ## Concepts
 
@@ -61,7 +62,7 @@ $ make image VERSION=latest
 You can also pull one from DockerHub.
 
 ```bash
-$ docker pull k8sdevops/harbor-cleaner:v0.1.1
+$ docker pull k8sdevops/harbor-cleaner:v0.2.0
 ```
 
 ### Configure
@@ -96,6 +97,12 @@ policy:
 
   # Tags that should be retained anyway, '?', '*' supported.
   retainTags: []
+# Trigger for the cleanup, if you only want to run cleanup once, remove the 'trigger' part or leave
+# the 'trigger.cron' empty
+trigger:
+  # Cron expression to trigger the cleanup, for example "0 0 * * *", leave it empty will disable the
+  # trigger and fallback to run cleanup once.
+  cron:
 ```
 
 In the policy part, exact one of `numberPolicy`, `regexPolicy` should be configured according to the policy type. 
@@ -105,15 +112,34 @@ In the policy part, exact one of `numberPolicy`, `regexPolicy` should be configu
 ```bash
 $ docker run -it --rm \
     -v <your-config-file>:/workspace/config.yaml \
-    harbor-cleaner:latest --dryrun=true
+    k8sdevops/harbor-cleaner:latest --dryrun=true
 ```
 
 ### Clean
 
 ```bash
 $ docker run -it --rm \
     -v <your-config-file>:/workspace/config.yaml \
-    harbor-cleaner:latest
+    k8sdevops/harbor-cleaner:latest
+```
+
+### Cron Schedule
+
+Configure the cron trigger and run harbor cleaner container in background.
+
+```yaml
+# Trigger for the cleanup, if you only want to run cleanup once, remove the 'trigger' part or leave
+# the 'trigger.cron' empty
+trigger:
+  # Cron expression to trigger the cleanup, for example "0 0 * * *", leave it empty will disable the
+  # trigger and fallback to run cleanup once.
+  cron: 0 0 * * *
+```
+
+```bash
+$ docker run -d --name=harbor-cleaner --rm \
+    -v <your-config-file>:/workspace/config.yaml \
+    k8sdevops/harbor-cleaner:latest
 ```
 
 ## Supported Version

cmd/config.yaml

@@ -27,3 +27,9 @@ policy:
 
   # Tags that should be retained anyway, '?', '*' supported.
   retainTags: []
+# Trigger for the cleanup, if you only want to run cleanup once, remove the 'trigger' part or leave
+# the 'trigger.cron' empty
+trigger:
+  # Cron expression to trigger the cleanup, for example "0 0 * * *", leave it empty will disable the
+  # trigger and fallback to run cleanup once. Note: you may need to quote the cron expression with double quote
+  cron:

cmd/main.go

@@ -15,6 +15,7 @@ import (
 	_ "github.com/cd1989/harbor-cleaner/pkg/policy/number"
 	_ "github.com/cd1989/harbor-cleaner/pkg/policy/regex"
 	_ "github.com/cd1989/harbor-cleaner/pkg/policy/touch"
+	"github.com/cd1989/harbor-cleaner/pkg/trigger"
 )
 
 var configFile *string
@@ -40,6 +41,20 @@ func main() {
 	}
 	harbor.APIClient = client
 
+	if config.HasCronSchedule() {
+		scheduler := trigger.NewCronScheduler(config.Config.Trigger.Cron)
+		scheduler.Submit(func() {
+			RunTask(client)
+		})
+		scheduler.Start()
+		<-ctx.Done()
+	} else {
+		RunTask(client)
+	}
+}
+
+// RunTask starts cleanup task
+func RunTask(client *harbor.Client) {
 	runner := cleaner.NewRunner(client, config.Config)
 	if *dryRun {
 		if err := runner.DryRun(); err != nil {

pkg/config/config.go

@@ -1,11 +1,11 @@
 package config
 
 import (
-	"io/ioutil"
-
 	"fmt"
+	"io/ioutil"
 	"strings"
 
+	"github.com/robfig/cron"
 	"github.com/sirupsen/logrus"
 	"gopkg.in/yaml.v2"
 )
@@ -38,12 +38,18 @@ type Policy struct {
 	RetainTags []string `yaml:"retainTags"`
 }
 
+type Trigger struct {
+	// Cron expression to regularly trigger the cleanup
+	Cron string `yaml:"cron"`
+}
+
 type C struct {
 	Host     string   `yaml:"host"`
 	Version  string   `yaml:"version"`
 	Auth     Auth     `yaml:"auth"`
 	Projects []string `yaml:"projects"`
 	Policy   Policy   `yaml:"policy"`
+	Trigger  *Trigger `yaml:"trigger"`
 }
 
 var Config = C{}
@@ -70,10 +76,22 @@ func Load(configFile string) error {
 
 func Normalize(c *C) error {
 	trimed := strings.TrimSpace(c.Version)
+	trimed = strings.TrimPrefix(trimed, "v")
 	if len(trimed) < 3 {
 		return fmt.Errorf("unrecoganized version %s, please provide version like 1.4, 1.7.5", c.Version)
 	}
-
 	c.Version = trimed[:3]
+
+	if HasCronSchedule() {
+		_, err := cron.ParseStandard(c.Trigger.Cron)
+		if err != nil {
+			return err
+		}
+	}
+
 	return nil
 }
+
+func HasCronSchedule() bool {
+	return Config.Trigger != nil && len(Config.Trigger.Cron) > 0
+}

pkg/trigger/cron.go

@@ -0,0 +1,58 @@
+package trigger
+
+import (
+	"time"
+
+	"github.com/robfig/cron"
+	"github.com/sirupsen/logrus"
+)
+
+type CronScheduler interface {
+	Submit(task func())
+	Start()
+}
+
+type cronScheduler struct {
+	passport chan struct{}
+	cronStr  string
+	cron     *cron.Cron
+}
+
+func NewCronScheduler(cronStr string) CronScheduler {
+	passport := make(chan struct{}, 1)
+	passport <- struct{}{}
+	return &cronScheduler{
+		passport: passport,
+		cronStr:  cronStr,
+		cron:     cron.New(),
+	}
+}
+
+func (s *cronScheduler) Submit(task func()) {
+	s.cron.AddFunc(s.cronStr, func() {
+		logrus.Info("Attempt to perform cleanup task")
+		var granted bool
+		select {
+		case <-s.passport:
+			granted = true
+		case <-time.After(time.Second):
+			granted = false
+		}
+
+		if !granted {
+			logrus.Info("Another cleanup task is still running, skip")
+			return
+		}
+
+		defer func() {
+			s.passport <- struct{}{}
+		}()
+
+		logrus.Info("Start to run cleanup task")
+		task()
+	})
+}
+
+func (s *cronScheduler) Start() {
+	s.cron.Start()
+}