Scheduled tasks commands

app/app.go

@@ -15,8 +15,10 @@ import (
 	"github.com/aws/aws-sdk-go/service/dynamodb"
 	"github.com/aws/aws-sdk-go/service/dynamodb/dynamodbattribute"
 	"github.com/aws/aws-sdk-go/service/ecs"
+	"github.com/aws/aws-sdk-go/service/eventbridge"
 	"github.com/aws/aws-sdk-go/service/s3"
 	"github.com/aws/aws-sdk-go/service/ssm"
+	"github.com/google/uuid"
 	"github.com/lincolnloop/apppack/auth"
 	"github.com/logrusorgru/aurora"
 )
@@ -576,6 +578,100 @@ func (a *App) ScaleProcess(processType string, minProcessCount int, maxProcessCo
 	return nil
 }
 
+type ScheduledTask struct {
+	Schedule string `json:"schedule"`
+	Command  string `json:"command"`
+}
+
+// ScheduledTasks lists scheduled tasks for the app
+func (a *App) ScheduledTasks() ([]*ScheduledTask, error) {
+	ssmSvc := ssm.New(a.Session)
+	parameterName := fmt.Sprintf("/paaws/apps/%s/scheduled-tasks", a.Name)
+	parameterOutput, err := ssmSvc.GetParameter(&ssm.GetParameterInput{
+		Name: &parameterName,
+	})
+	var tasks []*ScheduledTask
+	if err != nil {
+		tasks = []*ScheduledTask{}
+	} else {
+		if err = json.Unmarshal([]byte(*parameterOutput.Parameter.Value), &tasks); err != nil {
+			return nil, err
+		}
+	}
+	return tasks, nil
+}
+
+// CreateScheduledTask adds a scheduled task for the app
+func (a *App) CreateScheduledTask(schedule string, command string) ([]*ScheduledTask, error) {
+	if err := a.ValidateCronString(schedule); err != nil {
+		return nil, err
+	}
+	ssmSvc := ssm.New(a.Session)
+	tasks, err := a.ScheduledTasks()
+	if err != nil {
+		return nil, err
+	}
+	tasks = append(tasks, &ScheduledTask{
+		Schedule: schedule,
+		Command:  command,
+	})
+	tasksBytes, err := json.Marshal(tasks)
+	if err != nil {
+		return nil, err
+	}
+	parameterName := fmt.Sprintf("/paaws/apps/%s/scheduled-tasks", a.Name)
+	_, err = ssmSvc.PutParameter(&ssm.PutParameterInput{
+		Name:      &parameterName,
+		Value:     aws.String(fmt.Sprintf("%s", tasksBytes)),
+		Overwrite: aws.Bool(true),
+		Type:      aws.String("String"),
+	})
+	return tasks, nil
+}
+
+// DeleteScheduledTask deletes the scheduled task at the given index
+func (a *App) DeleteScheduledTask(idx int) (*ScheduledTask, error) {
+	ssmSvc := ssm.New(a.Session)
+	tasks, err := a.ScheduledTasks()
+	if err != nil {
+		return nil, err
+	}
+	if idx > len(tasks) || idx < 0 {
+		return nil, fmt.Errorf("invalid index for task to delete")
+	}
+	taskToDelete := tasks[idx]
+	tasks = append(tasks[:idx], tasks[idx+1:]...)
+	tasksBytes, err := json.Marshal(tasks)
+	if err != nil {
+		return nil, err
+	}
+	parameterName := fmt.Sprintf("/paaws/apps/%s/scheduled-tasks", a.Name)
+	_, err = ssmSvc.PutParameter(&ssm.PutParameterInput{
+		Name:      &parameterName,
+		Value:     aws.String(fmt.Sprintf("%s", tasksBytes)),
+		Overwrite: aws.Bool(true),
+		Type:      aws.String("String"),
+	})
+	return taskToDelete, nil
+}
+
+// ValidateCronString validates a cron schedule rule
+func (a *App) ValidateCronString(rule string) error {
+	eventSvc := eventbridge.New(a.Session)
+	ruleName := fmt.Sprintf("apppack-validate-%s", uuid.New().String())
+	_, err := eventSvc.PutRule(&eventbridge.PutRuleInput{
+		Name:               &ruleName,
+		ScheduleExpression: aws.String(fmt.Sprintf("cron(%s)", rule)),
+		State:              aws.String("DISABLED"),
+	})
+	if err == nil {
+		eventSvc.DeleteRule(&eventbridge.DeleteRuleInput{
+			Name: &ruleName,
+		})
+	}
+	return err
+}
+
 // Init will pull in app settings from DyanmoDB and provide helper
 func Init(name string) (*App, error) {
 	sess, err := auth.AwsSession(name)

cmd/scheduledTasks.go

@@ -0,0 +1,150 @@
+/*
+Copyright © 2020 NAME HERE <EMAIL ADDRESS>
+
+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 cmd
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+
+	"github.com/AlecAivazis/survey/v2"
+	"github.com/lincolnloop/apppack/app"
+	"github.com/logrusorgru/aurora"
+	"github.com/spf13/cobra"
+)
+
+func printTasks(tasks []*app.ScheduledTask) {
+	if len(tasks) == 0 {
+		fmt.Printf("%s", aurora.Yellow(fmt.Sprintf("no scheduled tasks defined")))
+		return
+	} else {
+		fmt.Printf("%s\n", aurora.Faint("Min\tHr\tDayMon\tMon\tDayWk\tYr"))
+	}
+	for _, task := range tasks {
+		fmt.Printf("%s\t%s\n", aurora.Faint(strings.Join(strings.Split(task.Schedule, " "), "\t")), task.Command)
+	}
+}
+
+// scheduledTasksCmd represents the scheduledTasks command
+var scheduledTasksCmd = &cobra.Command{
+	Use:   "scheduled-tasks",
+	Short: "A brief description of your command",
+	Long: `A longer description that spans multiple lines and likely contains examples
+and usage of using your command. For example:
+
+Cobra is a CLI library for Go that empowers applications.
+This application is a tool to generate the needed files
+to quickly create a Cobra application.`,
+	Run: func(cmd *cobra.Command, args []string) {
+		startSpinner()
+		a, err := app.Init(AppName)
+		checkErr(err)
+		tasks, err := a.ScheduledTasks()
+		Spinner.Stop()
+		checkErr(err)
+		printTasks(tasks)
+	},
+}
+
+var schedule string
+
+// scheduledTasksCreateCmd represents the create command
+var scheduledTasksCreateCmd = &cobra.Command{
+	Use:   "create --schedule \"...\" \"COMMAND\"",
+	Args:  cobra.ExactArgs(1),
+	Short: "A brief description of your command",
+	Long: `A longer description that spans multiple lines and likely contains examples
+and usage of using your command. For example:
+
+Cobra is a CLI library for Go that empowers applications.
+This application is a tool to generate the needed files
+to quickly create a Cobra application.`,
+	Run: func(cmd *cobra.Command, args []string) {
+		if len(strings.Split(schedule, " ")) != 6 {
+			checkErr(fmt.Errorf("schedule string should contain 6 space separated values\nhttps://docs.aws.amazon.com/eventbridge/latest/userguide/scheduled-events.html#cron-expressions"))
+		}
+		command := strings.Join(args, " ")
+		startSpinner()
+		a, err := app.Init(AppName)
+		checkErr(err)
+		tasks, err := a.CreateScheduledTask(schedule, command)
+		Spinner.Stop()
+		checkErr(err)
+		printSuccess("task created")
+		printTasks(tasks)
+	},
+}
+
+// scheduledTasksCreateCmd represents the create command
+var scheduledTasksDeleteCmd = &cobra.Command{
+	Use:   "delete [INDEX]",
+	Args:  cobra.MaximumNArgs(1),
+	Short: "A brief description of your command",
+	Long: `A longer description that spans multiple lines and likely contains examples
+and usage of using your command. For example:
+
+Cobra is a CLI library for Go that empowers applications.
+This application is a tool to generate the needed files
+to quickly create a Cobra application.`,
+	Run: func(cmd *cobra.Command, args []string) {
+		startSpinner()
+		a, err := app.Init(AppName)
+		checkErr(err)
+		var idx int
+		var task *app.ScheduledTask
+		if len(args) > 0 {
+			idx, err = strconv.Atoi(args[0])
+			checkErr(err)
+			idx--
+		} else {
+			tasks, err := a.ScheduledTasks()
+			checkErr(err)
+			taskList := []string{}
+			for _, t := range tasks {
+				taskList = append(taskList, fmt.Sprintf("%s %s", t.Schedule, t.Command))
+			}
+			questions := []*survey.Question{{
+				Name: "task",
+				Prompt: &survey.Select{
+					Message:       "Scheduled task to delete:",
+					Options:       taskList,
+					FilterMessage: "",
+				},
+			}}
+			answers := make(map[string]int)
+			Spinner.Stop()
+			if err := survey.Ask(questions, &answers); err != nil {
+				checkErr(err)
+			}
+			idx = answers["task"]
+		}
+		task, err = a.DeleteScheduledTask(idx)
+		checkErr(err)
+		printSuccess("scheduled task deleted:")
+		fmt.Printf("  %s %s\n", aurora.Faint(task.Schedule), task.Command)
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(scheduledTasksCmd)
+	scheduledTasksCmd.PersistentFlags().StringVarP(&AppName, "app-name", "a", "", "App name (required)")
+	scheduledTasksCmd.MarkPersistentFlagRequired("app-name")
+
+	scheduledTasksCmd.AddCommand(scheduledTasksCreateCmd)
+	scheduledTasksCreateCmd.Flags().StringVarP(&schedule, "schedule", "s", "", "Cron-like schedule. See https://docs.aws.amazon.com/eventbridge/latest/userguide/scheduled-events.html#cron-expressions")
+
+	scheduledTasksCmd.AddCommand(scheduledTasksDeleteCmd)
+}