feat: implement backup command

TODO.md

@@ -16,7 +16,7 @@
   - [ ] `abra app`
     - [x] `ls`
     - [x] `new`
-    - [ ] `backup` (WIP: decentral1se)
+    - [x] `backup`
     - [ ] `deploy`
     - [ ] `check`
     - [x] `version`

cli/app/backup.go

@@ -1,6 +1,17 @@
 package app
 
 import (
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path"
+	"strings"
+
+	"coopcloud.tech/abra/cli/internal"
+	"coopcloud.tech/abra/config"
+	"github.com/sirupsen/logrus"
 	"github.com/urfave/cli/v2"
 )
 
@@ -9,10 +20,70 @@ var backupAllServicesFlag = &cli.BoolFlag{
 	Name:        "all",
 	Value:       false,
 	Destination: &backupAllServices,
+	Aliases:     []string{"a"},
 	Usage:       "Backup all services",
 }
 
 var appBackupCommand = &cli.Command{
-	Name:  "backup",
-	Flags: []cli.Flag{backupAllServicesFlag},
+	Name:      "backup",
+	Flags:     []cli.Flag{backupAllServicesFlag},
+	ArgsUsage: "<service>",
+	Action: func(c *cli.Context) error {
+		appName := c.Args().First()
+		if appName == "" {
+			internal.ShowSubcommandHelpAndError(c, errors.New("no app name provided"))
+		}
+
+		if c.Args().Get(1) != "" && backupAllServices {
+			internal.ShowSubcommandHelpAndError(c, errors.New("cannot use '<service>' and '--all' together"))
+		}
+
+		appFiles, err := config.LoadAppFiles("")
+		if err != nil {
+			logrus.Fatal(err)
+		}
+
+		appEnv, err := config.GetApp(appFiles, appName)
+		if err != nil {
+			logrus.Fatal(err)
+		}
+
+		abraSh := path.Join(config.ABRA_DIR, "apps", appEnv.Type, "abra.sh")
+		if _, err := os.Stat(abraSh); err != nil {
+			if os.IsNotExist(err) {
+				logrus.Fatalf("'%s' does not exist?", abraSh)
+			}
+			logrus.Fatal(err)
+		}
+
+		sourceCmd := fmt.Sprintf("source %s", abraSh)
+
+		execCmd := "abra_backup"
+		if !backupAllServices {
+			serviceName := c.Args().Get(1)
+			if serviceName == "" {
+				internal.ShowSubcommandHelpAndError(c, errors.New("no service(s) target provided"))
+			}
+			execCmd = fmt.Sprintf("abra_backup_%s", serviceName)
+		}
+
+		bytes, err := ioutil.ReadFile(abraSh)
+		if err != nil {
+			logrus.Fatal(err)
+		}
+		if !strings.Contains(string(bytes), execCmd) {
+			logrus.Fatalf("%s doesn't have a '%s' function", appEnv.Type, execCmd)
+		}
+
+		sourceAndExec := fmt.Sprintf("%s; %s", sourceCmd, execCmd)
+		cmd := exec.Command("bash", "-c", sourceAndExec)
+		output, err := cmd.Output()
+		if err != nil {
+			logrus.Fatal(err)
+		}
+
+		fmt.Print(string(output))
+
+		return nil
+	},
 }