Update to cron v3, ability to show next issues creation timestamps and little refactor.

Makefile

@@ -12,6 +12,11 @@ run:
 	GPT_CONFIG=$(CONFIG) ./periodicator
 	rm periodicator
 
+run-show-next-creation-ts:
+	go build -ldflags $(LINKER_FLAGS) -o periodicator .
+	GPT_CONFIG=$(CONFIG) ./periodicator -show-next-creation-ts
+	rm periodicator
+
 run-version:
 	go build -ldflags $(LINKER_FLAGS) -o periodicator .
 	GPT_CONFIG=$(CONFIG) ./periodicator -version

go.mod

@@ -3,12 +3,13 @@ module go.dev.pztrn.name/periodicator
 go 1.17
 
 require (
-	github.com/robfig/cron v1.2.0
+	github.com/robfig/cron/v3 v3.0.1
 	github.com/xanzy/go-gitlab v0.51.1
 	gopkg.in/yaml.v2 v2.2.2
 )
 
 require (
+	github.com/adhocore/gronx v0.2.5 // indirect
 	github.com/golang/protobuf v1.5.2 // indirect
 	github.com/google/go-querystring v1.1.0 // indirect
 	github.com/hashicorp/go-cleanhttp v0.5.2 // indirect

go.sum

@@ -33,6 +33,8 @@ cloud.google.com/go/storage v1.10.0/go.mod h1:FLPqc6j+Ki4BU591ie1oL6qBQGu2Bl/tZ9
 dmitri.shuralyov.com/gpu/mtl v0.0.0-20190408044501-666a987793e9/go.mod h1:H6x//7gZCb22OMCxBHrMx7a5I7Hp++hsVxbQ4BYO7hU=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/BurntSushi/xgb v0.0.0-20160522181843-27f122750802/go.mod h1:IVnqGOEym/WlBOVXweHU+Q+/VP0lqqI8lqeDx9IjBqo=
+github.com/adhocore/gronx v0.2.5 h1:trVgNYPle0IcsGDt0XGz78zN8Soek0YrcQtQ+Cs+jko=
+github.com/adhocore/gronx v0.2.5/go.mod h1:7oUY1WAU8rEJWmAxXR2DN0JaO4gi9khSgKjiRypqteg=
 github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
 github.com/chzyer/logex v1.1.10/go.mod h1:+Ywpsq7O8HXn0nuIou7OrIPyXbp3wmkHB+jjWRnGsAI=
 github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e/go.mod h1:nSuG5e5PlCu98SY8svDHJxuZscDgtXS6KTTbou5AhLI=
@@ -125,8 +127,8 @@ github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/prometheus/client_model v0.0.0-20190812154241-14fe0d1b01d4/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
-github.com/robfig/cron v1.2.0 h1:ZjScXvvxeQ63Dbyxy76Fj3AT3Ut0aKsyd2/tl3DTMuQ=
+github.com/robfig/cron/v3 v3.0.1 h1:WdRxkvbJztn8LMz/QEvLN5sBU+xKpSqwwUO1Pjr4qDs=
-github.com/robfig/cron v1.2.0/go.mod h1:JGuDeoQd7Z6yL4zQhZ3OPEVHB7fL6Ka6skscFHfmt2k=
+github.com/robfig/cron/v3 v3.0.1/go.mod h1:eQICP3HwyT7UooqI/z+Ov+PtYAWygg1TEWWzGIFLtro=
 github.com/rogpeppe/go-internal v1.3.0/go.mod h1:M8bDsm7K2OlrFYOpmOWEs/qY81heoFRclV5y23lUDJ4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=

internal/tasks/base.go

@@ -4,7 +4,7 @@ import (
 	"log"
 	"time"
 
-	"github.com/robfig/cron"
+	"github.com/robfig/cron/v3"
 	g "github.com/xanzy/go-gitlab"
 	"go.dev.pztrn.name/periodicator/internal/gitlab"
 )
@@ -39,6 +39,37 @@ func (b *BaseTask) checkIfOpenedTaskExists(issues []*g.Issue) bool {
 	return foundAndNotClosed
 }
 
+func (b *BaseTask) getIssues() ([]*g.Issue, error) {
+	// nolint:wrapcheck
+	return b.client.GetIssuesByTitle(b.projectID, b.title)
+}
+
+func (b *BaseTask) getLastCreationTimestamp(issues []*g.Issue) time.Time {
+	lastTaskCreationTS := b.executionStartTimestamp
+
+	for _, issue := range issues {
+		if issue.ClosedAt != nil && issue.CreatedAt.After(lastTaskCreationTS) {
+			lastTaskCreationTS = *issue.CreatedAt
+		}
+	}
+
+	return lastTaskCreationTS
+}
+
+func (b *BaseTask) getNextCreationTimestamp(lastTaskCreationTS time.Time) time.Time {
+	// Set up cron job parser.
+	cp := cron.NewParser(cron.Minute | cron.Hour | cron.Dom | cron.Month | cron.Dow)
+
+	schedule, err := cp.Parse(b.cron)
+	if err != nil {
+		b.log("Failed to parse cron string: " + err.Error())
+
+		return lastTaskCreationTS
+	}
+
+	return schedule.Next(lastTaskCreationTS)
+}
+
 func (b *BaseTask) log(message string) {
 	log.Println("Task '" + b.title + "': " + message)
 }
@@ -46,7 +77,7 @@ func (b *BaseTask) log(message string) {
 // Run executes task procedure.
 func (b *BaseTask) Run() {
 	// Get similar tasks.
-	issues, err := b.client.GetIssuesByTitle(b.projectID, b.title)
+	issues, err := b.getIssues()
 	if err != nil {
 		b.log("Error while getting issues from Gitlab: " + err.Error())
 
@@ -65,29 +96,16 @@ func (b *BaseTask) Run() {
 	b.log("No still opened tasks found, checking if we should create new one...")
 
 	// Get latest task creation timestamp from Gitlab.
-	lastTaskCreationTS := b.executionStartTimestamp
+	lastTaskCreationTS := b.getLastCreationTimestamp(issues)
-
-	for _, issue := range issues {
-		if issue.ClosedAt != nil && issue.CreatedAt.After(lastTaskCreationTS) {
-			lastTaskCreationTS = *issue.CreatedAt
-		}
-	}
 
 	b.log("Last task creation timestamp: " + lastTaskCreationTS.String())
 
-	// Set up cron job parser.
+	// Figure out next task creation and deadline timestamps.
-	cp := cron.NewParser(cron.Minute | cron.Hour | cron.Dom | cron.Month | cron.Dow)
+	nextCreationTS := b.getNextCreationTimestamp(lastTaskCreationTS)
-
+	if nextCreationTS.Equal(lastTaskCreationTS) {
-	schedule, err := cp.Parse(b.cron)
-	if err != nil {
-		b.log("Failed to parse cron string: " + err.Error())
-
 		return
 	}
 
-	// Figure out next task creation and deadline timestamps.
-	nextCreationTS := schedule.Next(lastTaskCreationTS)
-
 	// Check if task should be created and create if so.
 	if nextCreationTS.Before(time.Now()) {
 		// Deadlines should be calculated until first one will appear AFTER today.

internal/tasks/tasks.go

@@ -4,6 +4,31 @@ import (
 	"go.dev.pztrn.name/periodicator/internal/gitlab"
 )
 
+// PrintCreationTSes prints tasks creation timestamps.
+func PrintCreationTSes(client *gitlab.Client, tasks []Config) {
+	for _, task := range tasks {
+		t := &BaseTask{
+			client:                  client,
+			projectID:               task.ProjectID,
+			title:                   task.Title,
+			body:                    task.Body,
+			tags:                    task.Tags,
+			executionStartTimestamp: task.ExecutionStart.GetTimestamp(),
+			cron:                    task.Cron,
+			dueIn:                   task.DueIn,
+		}
+
+		// Get similar tasks.
+		// ToDo: refactor?
+		issues, err := t.getIssues()
+		if err != nil {
+			panic("Error while getting issues from Gitlab: " + err.Error())
+		}
+
+		t.log(t.getNextCreationTimestamp(t.getLastCreationTimestamp(issues)).String())
+	}
+}
+
 // Process processes passed tasks.
 func Process(client *gitlab.Client, tasks []Config) {
 	for _, task := range tasks {

main.go

@@ -11,7 +11,10 @@ import (
 	"go.dev.pztrn.name/periodicator/internal/tasks"
 )
 
-var showVersion = flag.Bool("version", false, "Show version information and exit")
+var (
+	showNextCreationTS = flag.Bool("show-next-creation-ts", false, "Show tasks next creation timestamps")
+	showVersion        = flag.Bool("version", false, "Show version information and exit")
+)
 
 func main() {
 	flag.Parse()
@@ -28,5 +31,10 @@ func main() {
 
 	c := gitlab.NewGitlabClient(&cfg.Gitlab)
 
+	if *showNextCreationTS {
+		tasks.PrintCreationTSes(c, cfg.Tasks)
+		os.Exit(0)
+	}
+
 	tasks.Process(c, cfg.Tasks)
 }