CLI: Download Detector Configuration as File

cli/cmd/cat.go

@@ -17,6 +17,8 @@ import (
 	entity "esad/internal/entity/ad"
 	"esad/internal/handler/ad"
 	"fmt"
+	"io"
+	"os"
 
 	"github.com/spf13/cobra"
 )
@@ -33,30 +35,35 @@ var catCmd = &cobra.Command{
 	Run: func(cmd *cobra.Command, args []string) {
 		//If no args, display usage
 		if len(args) < 1 {
-			if err := cmd.Usage(); err != nil {
-				fmt.Println(err)
-			}
+			displayError(cmd.Usage(), commandCat)
 			return
 		}
-		idStatus, _ := cmd.Flags().GetBool("id")
-		commandHandler, err := getCommandHandler()
-		if err != nil {
-			fmt.Println(err)
-		}
-		// default is name
-		action := ad.GetAnomalyDetectorsByNamePattern
-		if idStatus {
-			action = getDetectorsByID
-		}
-		results, err := getDetectors(commandHandler, args, action)
-		if err != nil {
-			fmt.Println(err)
-			return
-		}
-		printDetectors(results)
+		err := printDetectors(Println, cmd, args)
+		displayError(err, commandCat)
 	},
 }
 
+type Display func(*cobra.Command, *entity.DetectorOutput) error
+
+//printDetectors print detectors
+func printDetectors(display Display, cmd *cobra.Command, detectors []string) error {
+	idStatus, _ := cmd.Flags().GetBool("id")
+	commandHandler, err := getCommandHandler()
+	if err != nil {
+		return err
+	}
+	// default is name
+	action := ad.GetAnomalyDetectorsByNamePattern
+	if idStatus {
+		action = getDetectorsByID
+	}
+	results, err := getDetectors(commandHandler, detectors, action)
+	if err != nil {
+		return err
+	}
+	return print(cmd, display, results)
+}
+
 func getDetectors(
 	commandHandler *ad.Handler, args []string, get func(*ad.Handler, string) (
 		[]*entity.DetectorOutput, error)) ([]*entity.DetectorOutput, error) {
@@ -81,20 +88,33 @@ func getDetectorsByID(commandHandler *ad.Handler, ID string) ([]*entity.Detector
 	return []*entity.DetectorOutput{output}, nil
 }
 
-//printDetectors displays the list of output. Since this is json format, use indent function to
-// pretty print before printing on console
-func printDetectors(results []*entity.DetectorOutput) {
+//print displays the list of output.
+func print(cmd *cobra.Command, display Display, results []*entity.DetectorOutput) error {
 	if results == nil {
-		return
+		return nil
 	}
 	for _, d := range results {
-		formattedOutput, err := json.MarshalIndent(d, "", "  ")
-		if err != nil {
-			fmt.Println(err)
-			return
+		if err := display(cmd, d); err != nil {
+			return err
 		}
-		fmt.Println(string(formattedOutput))
 	}
+	return nil
+}
+
+//FPrint prints detector configuration on writer
+//Since this is json format, use indent function to pretty print before printing on writer
+func FPrint(writer io.Writer, d *entity.DetectorOutput) error {
+	formattedOutput, err := json.MarshalIndent(d, "", "  ")
+	if err != nil {
+		return err
+	}
+	_, err = fmt.Fprintln(writer, string(formattedOutput))
+	return err
+}
+
+//Println prints detector configuration on stdout
+func Println(cmd *cobra.Command, d *entity.DetectorOutput) error {
+	return FPrint(os.Stdout, d)
 }
 
 func init() {

cli/cmd/create.go

@@ -39,17 +39,12 @@ var createCmd = &cobra.Command{
 		}
 		//If no args, display usage
 		if len(args) < 1 {
-			if err := cmd.Usage(); err != nil {
-				fmt.Println(err)
-			}
+			displayError(cmd.Usage(), commandCreate)
 			return
 		}
 		status, _ := cmd.Flags().GetBool(interactive)
 		err := createDetectors(args, status)
-		if err != nil {
-			fmt.Println(commandCreate, "command failed")
-			fmt.Println("Reason:", err)
-		}
+		displayError(err, commandCreate)
 	},
 }
 

cli/cmd/delete.go

@@ -14,7 +14,6 @@ package cmd
 
 import (
 	handler "esad/internal/handler/ad"
-	"fmt"
 
 	"github.com/spf13/cobra"
 )
@@ -30,9 +29,7 @@ var deleteCmd = &cobra.Command{
 	Run: func(cmd *cobra.Command, args []string) {
 		//If no args, display usage
 		if len(args) < 1 {
-			if err := cmd.Usage(); err != nil {
-				fmt.Println(err)
-			}
+			displayError(cmd.Usage(), commandDelete)
 			return
 		}
 		force, _ := cmd.Flags().GetBool("force")
@@ -42,10 +39,7 @@ var deleteCmd = &cobra.Command{
 			action = handler.DeleteAnomalyDetectorByID
 		}
 		err := deleteDetectors(args, force, action)
-		if err != nil {
-			fmt.Println(commandDelete, "command failed")
-			fmt.Println("Reason:", err)
-		}
+		displayError(err, commandDelete)
 	},
 }
 

cli/cmd/download.go

@@ -0,0 +1,107 @@
+/*
+ * Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Licensed under the Apache License, Version 2.0 (the "License").
+ * You may not use this file except in compliance with the License.
+ * A copy of the License is located at
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * or in the "license" file accompanying this file. This file 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 (
+	entity "esad/internal/entity/ad"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/spf13/cobra"
+)
+
+const (
+	commandDownload   = "download"
+	flagOutput        = "output"
+	fileExtensionJSON = "json"
+)
+
+//downloadCmd downloads detectors configuration on current working directory
+//based on detector id or name patter
+var downloadCmd = &cobra.Command{
+	Use:   commandDownload + " [flags] [list of detectors]",
+	Short: "Downloads detectors configurations based on id or name pattern",
+	Long: fmt.Sprintf("Description:\n  " +
+		`Downloads detectors configurations based on id or name pattern, use "" to make sure the name is not matched with pwd lists'`),
+	Run: func(cmd *cobra.Command, args []string) {
+		//If no args, display usage
+		if len(args) < 1 {
+			displayError(cmd.Usage(), commandDownload)
+			return
+		}
+		err := printDetectors(WriteInFile, cmd, args)
+		displayError(err, commandDownload)
+	},
+}
+
+//WriteInFile writes detector's configuration on file
+//file will be created inside current working directory,
+//with detector name as file name
+func WriteInFile(cmd *cobra.Command, d *entity.DetectorOutput) error {
+	output, _ := cmd.Flags().GetString(flagOutput)
+	if _, err := os.Stat(output); os.IsNotExist(err) {
+		return fmt.Errorf("output directory [%s] does not exists", output)
+	}
+	filePath := filepath.Join(output, fmt.Sprintf("%s.%s", d.Name, fileExtensionJSON))
+	if ok := isCreateFileAllowed(filePath); !ok {
+		return nil
+	}
+	f, err := os.Create(filePath)
+	defer func() {
+		f.Close()
+	}()
+	if err != nil {
+		return err
+	}
+	return FPrint(f, d)
+}
+
+func isCreateFileAllowed(path string) bool {
+	if _, err := os.Stat(path); os.IsNotExist(err) {
+		return true
+	}
+	return askForConfirmation(path)
+}
+
+func askForConfirmation(path string) bool {
+
+	fmt.Printf("overwrite %s? (y/n [n])", filepath.Base(path))
+	var response string
+	_, err := fmt.Fscanln(os.Stdin, &response)
+	if err != nil {
+		//Exit if for some reason, we are not able to accept user input
+		fmt.Printf("failed to accept value from user due to %s", err)
+		return false
+	}
+	switch strings.ToLower(response) {
+	case "y", "yes":
+		return true
+	case "n", "no":
+		return false
+	default:
+		return false
+	}
+}
+
+func init() {
+	esadCmd.AddCommand(downloadCmd)
+	downloadCmd.Flags().BoolP("name", "", true, "input is name or pattern")
+	downloadCmd.Flags().BoolP("id", "", false, "input is id")
+	cwd, err := os.Getwd()
+	if err != nil {
+		fmt.Println("failed to find current working directory due to ", err)
+	}
+	downloadCmd.Flags().StringP(flagOutput, "o", cwd, "downloads detectors inside this folder path")
+}

cli/cmd/root.go

@@ -111,3 +111,10 @@ func GetHandler(c *client.Client, u *client.UserConfig) *handler.Handler {
 	ctr := controller.New(os.Stdin, esc, g)
 	return handler.New(ctr)
 }
+
+func displayError(err error, cmdName string) {
+	if err != nil {
+		fmt.Println(cmdName, "command failed")
+		fmt.Println("Reason: ", err)
+	}
+}

cli/cmd/start_stop.go

@@ -15,7 +15,6 @@ package cmd
 import (
 	"esad/internal/client"
 	"esad/internal/handler/ad"
-	"fmt"
 
 	"github.com/spf13/cobra"
 )
@@ -32,16 +31,17 @@ var startCmd = &cobra.Command{
 	Short: "Start detectors based on an ID or name pattern",
 	Long:  `Start detectors based on a pattern. Use "" to make sure the name does not match with pwd lists'`,
 	Run: func(cmd *cobra.Command, args []string) {
+		if len(args) < 1 {
+			displayError(cmd.Usage(), commandStop)
+			return
+		}
 		idStatus, _ := cmd.Flags().GetBool("id")
 		action := ad.StartAnomalyDetectorByNamePattern
 		if idStatus {
 			action = ad.StartAnomalyDetectorByID
 		}
 		err := execute(action, args)
-		if err != nil {
-			fmt.Println(commandStart, "command failed")
-			fmt.Println("Reason:", err)
-		}
+		displayError(err, commandStart)
 	},
 }
 
@@ -54,9 +54,7 @@ var stopCmd = &cobra.Command{
 	Run: func(cmd *cobra.Command, args []string) {
 		//If no args, display usage
 		if len(args) < 1 {
-			if err := cmd.Usage(); err != nil {
-				fmt.Println(err)
-			}
+			displayError(cmd.Usage(), commandStop)
 			return
 		}
 		idStatus, _ := cmd.Flags().GetBool("id")
@@ -65,10 +63,7 @@ var stopCmd = &cobra.Command{
 			action = ad.StopAnomalyDetectorByID
 		}
 		err := execute(action, args)
-		if err != nil {
-			fmt.Println(commandStop, "command failed")
-			fmt.Println("Reason:", err)
-		}
+		displayError(err, commandStop)
 	},
 }