feat: support service completion

Closes coop-cloud/organising#165.

cli/app/run.go

@@ -102,15 +102,24 @@ var appRunCommand = &cli.Command{
 		return nil
 	},
 	BashComplete: func(c *cli.Context) {
-		appNames, err := config.GetAppNames()
-		if err != nil {
-			logrus.Warn(err)
-		}
-		if c.NArg() > 0 {
-			return
-		}
-		for _, a := range appNames {
-			fmt.Println(a)
+		switch c.NArg() {
+		case 0:
+			appNames, err := config.GetAppNames()
+			if err != nil {
+				logrus.Warn(err)
+			}
+			for _, a := range appNames {
+				fmt.Println(a)
+			}
+		case 1:
+			appName := c.Args().First()
+			serviceNames, err := config.GetAppServiceNames(appName)
+			if err != nil {
+				logrus.Warn(err)
+			}
+			for _, s := range serviceNames {
+				fmt.Println(s)
+			}
 		}
 	},
 }

pkg/config/app.go

@@ -190,6 +190,38 @@ func GetApps(appFiles AppFiles) ([]App, error) {
 	return apps, nil
 }
 
+// GetAppServiceNames retrieves a list of app service names.
+func GetAppServiceNames(appName string) ([]string, error) {
+	var serviceNames []string
+
+	appFiles, err := LoadAppFiles("")
+	if err != nil {
+		return serviceNames, err
+	}
+
+	app, err := GetApp(appFiles, appName)
+	if err != nil {
+		return serviceNames, err
+	}
+
+	composeFiles, err := GetAppComposeFiles(app.Type, app.Env)
+	if err != nil {
+		return serviceNames, err
+	}
+
+	opts := stack.Deploy{Composefiles: composeFiles}
+	compose, err := GetAppComposeConfig(app.Type, opts, app.Env)
+	if err != nil {
+		return serviceNames, err
+	}
+
+	for _, service := range compose.Services {
+		serviceNames = append(serviceNames, service.Name)
+	}
+
+	return serviceNames, nil
+}
+
 // GetAppNames retrieves a list of app names.
 func GetAppNames() ([]string, error) {
 	var appNames []string