add backup subcommand

client/v1/client.go

@@ -8,7 +8,6 @@ import (
 	"fmt"
 	"io"
 	"io/ioutil"
-	"log"
 	"net/http"
 	"net/url"
 	"path"
@@ -2185,13 +2184,12 @@ func (c *Client) DoStorageAction(l Link, opt StorageActionOptions) error {
 	return nil
 }
 
-// StorageBackup requests a backup of all storage from Kapacitor.
+// Backup requests a backup of all storage from Kapacitor.
 // A short read is possible, to verify that the backup was successful
 // check that the number of bytes read matches the returned size.
-func (c *Client) StorageBackup() (int64, io.ReadCloser, error) {
+func (c *Client) Backup() (int64, io.ReadCloser, error) {
 	u := *c.url
 	u.Path = backupPath
-	log.Println("D! PATH", backupPath)
 
 	req, err := http.NewRequest("GET", u.String(), nil)
 	if err != nil {

cmd/kapacitor/main.go

@@ -62,6 +62,7 @@ Commands:
 	show-template         Display detailed information about a template.
 	show-topic-handler    Display detailed information about an alert handler for a topic.
 	show-topic            Display detailed information about an alert topic.
+	backup                Backup the Kapacitor database.
 	level                 Sets the logging level on the kapacitord server.
 	stats                 Display various stats about Kapacitor.
 	version               Displays the Kapacitor version info.
@@ -180,6 +181,9 @@ func main() {
 	case "show-topic":
 		commandArgs = args
 		commandF = doShowTopic
+	case "backup":
+		commandArgs = args
+		commandF = doBackup
 	case "level":
 		commandArgs = args
 		commandF = doLevel
@@ -278,6 +282,8 @@ func doHelp(args []string) error {
 			showTopicHandlerUsage()
 		case "show-topic":
 			showTopicUsage()
+		case "backup":
+			backupUsage()
 		case "level":
 			levelUsage()
 		case "help":
@@ -2206,3 +2212,37 @@ func doServiceTest(args []string) error {
 	}
 	return nil
 }
+
+// Backup
+func backupUsage() {
+	var u = `Usage: kapacitor backup <output file>
+
+	Perform a backup of the Kapacitor database.
+
+	To restore a database first stop Kapacitor, then replace the existing kapacitor.db file with the backup file.
+`
+	fmt.Fprintln(os.Stderr, u)
+}
+
+func doBackup(args []string) error {
+	if len(args) != 1 {
+		return errors.New("must provide file path for backup.")
+	}
+	f, err := os.Create(args[0])
+	if err != nil {
+		return errors.Wrap(err, "failed to create backup file")
+	}
+	defer f.Close()
+	size, backup, err := cli.Backup()
+	if err != nil {
+		return errors.Wrap(err, "failed to perform backup")
+	}
+	n, err := io.Copy(f, backup)
+	if err != nil {
+		return errors.Wrap(err, "failed to save backup")
+	}
+	if n != size {
+		return fmt.Errorf("failed to download entire backup, only wrote %d bytes out of a total %d bytes.", n, size)
+	}
+	return nil
+}

server/server_test.go

@@ -9021,7 +9021,7 @@ func TestStorage_Backup(t *testing.T) {
 	}
 
 	// Perform backup
-	size, r, err := cli.StorageBackup()
+	size, r, err := cli.Backup()
 	if err != nil {
 		t.Fatal(err)
 	}

usr/share/bash-completion/completions/kapacitor

@@ -186,6 +186,8 @@ _kapacitor()
         show-topic)
             words=$(_kapacitor_list topics "$cur")
             ;;
+        backup)
+            ;;
         level)
             words='debug info warn error'
             ;;
@@ -200,7 +202,7 @@ _kapacitor()
             ;;
         *)
             words='record define define-template define-topic-handler replay replay-live enable disable \
-                reload delete list show show-template show-topic-handler show-topic level stats version vars service-tests help'
+                reload delete list show show-template show-topic-handler show-topic backup level stats version vars service-tests help'
             ;;
     esac
     if [ -z "$COMPREPLY" ]